The Electricity Generation Mass Balance

ecolateral.org

The Electricity Generation Mass Balance

Prepared byC-Tech Innovation is an independent technology development and multidisciplinaryconsultancy company that helps customers with research and commercialisationof innovative products and processes.investing in the environmentSponsored byC-Tech Innovation Ltd,Capenhurst Technology Park, Chester, CH1 6ESTel: 0151 347 2900 Fax: 0151 347 2901Website: www.capenhurst.comRegistered in England number 4050834© C-Tech Innovation Ltd, 2003Designed and printed by RAS Design, Chester 01244 346666


AProgramme onSustainableResourceUse


Care has been taken in the preparation of this report, but all advice, analysis, calculations, information, forecasts andrecommendations are supplied for the assistance of the relevant client and are not to be relied on as authoritative or asin substitution for the exercise of judgement by that client or any other reader. Neither C-Tech Innovation Ltd nor any ofits personnel engaged in the preparation of this report shall have any liability whatsoever for any direct or consequentialloss arising from use of this report or its contents and give no warranty or representation (express or implied) as to thequality or fitness for the purpose of any process, material, product or system referred to in the report.All rights reserved. No part of this report may be reproduced or transmitted in any form or by any means electronic,mechanical, photocopied, recorded or otherwise, or stored in any retrieval system of any nature without the writtenpermission of the copyright holder.


Electricity Report - ForwardFor the past 200 years society has become used to quantifying and understanding efficiency in 2 broad dimensions:• labour and people input,• financial costs.Few have paused to think about the efficiency of the way we deliver goods and services in terms of physical resource inputsand outputs. This publication is an attempt to refocus our thoughts in that direction in relation to electrical power.Why bother? After all the environment is “free”. We can use air or relatively low cost raw materials such as minerals,carbon or energy at will – it is the application and conversion of those resources that comes expensive.We are now coming to terms with reality – that the profligate use of low “financially” priced resources has resulted in theintroduction of large quantities of liquid, gaseous or solid waste into the world at a rate faster than the eco-system can returnit to its original state – if at all. The consequences of this may not necessarily be as cheap as we thought – indeed we areyet to count the future cost in terms of health, climate change and biodiversity loss.Few in society recognise that our developed economy is consuming in excess of 10 tonnes of raw material resources forevery one tonne of output purchased at the point of sale by private individuals. Much the same ratios apply to specificsectors – and energy is no exception. Indeed – as a weightless product – the ratios for electrical power are infinite! In 1998the Government introduced the means by which Biffa could fund work undertaken by those keen to explore the implicationsof this level of inefficiency. The Landfill Tax Credit Scheme has allowed us to commit over £8m in the last 4 years to morethan 50 such sector studies which look at the dynamic of resource flows through different regions, industry sectors andresource lifecycles.Environmental impacts come in the form of widespread use of non renewable materials sourced and disposed of in waysthat don’t necessarily represent the best deal for society in the long run. For the cynics among us, the dictum that it will befinancial costs that drive the process is probably the right one and those costs are set to rise. Landfill Tax has risen at a mere£1 per tonne over the last 7 years and the Chancellor has announced a £35 cap for around 2011 – driven by higher levelsof awareness on the workings of environmental taxation in the Government, as well as increased pressures resulting fromthe recent spending round. Additionally, a much wider range of materials being used are about to be reclassified ashazardous with the consequence that they will be banned from landfill and, of necessity, treated in ways which recover theirconstituent elements for reuse in other product cycles. Producer Responsibility, targets and Traded Pollution Permits are alladding to the emergent tapestry of Environmental instruments.The energy sector is going to have to learn how to trade-off these new economic as well as environmental realities.Apart from the cost push pressures driven by European and UK legislation/regulation, there are also the expectations of your“market place”. Generators are under increasing pressure to develop internal reporting guidelines on all aspects of theirenvironmental track record. Unfortunately this report will create more questions than it answers – but that is always the casewith such leading edge work. It certainly highlights the chronic absence of reliable data on resource generally. This shouldbe no surprise given parallel paucity of data on mainstream areas under management – particularly waste – where policymakingis bedevilled by an absence of an integrated framework or sets of common definitional protocols. Indeed, in part,this publication should trigger questions in the context of the e-Government initiative. Today it is but a dream to believe thata comprehensive overview of resource inputs into and out of UK Plc could be obtained at the flick of a button!This publication is designed to present the wider picture and inform the debate. If you wish to explore the issues outsideyour own industry, then find out more about the Biffa Mass Balance Programme on www.massbalance.org and seeexamples of some of the 50 odd commissioned studies which have reported thus far.Peter JonesDirector - Development and External RelationsBiffa LtdBiffaward Programme on Sustainable Resource Use – ObjectivesThis report forms part of the Biffaward Programme on Sustainable Resource Use. The Programme aims to provide accessible, wellresearched information about the flows of different resources through the UK economy based either singly or in combination on regions,material streams and economic sectors. Information about material resource flows through the economy is of fundamental importanceto the cost effective management of resource flows, especially at the stage when those resources become waste. In order to maximisethe Programme’s full potential, data will be generated and classified in ways which are consistent with each other and with themethodologies of other generators of resource flow/waste management data.


Contents1234567891 The Electricity Generation Mass Balance Page1.1 Introduction 11.2 The Electricity Generation Industry 11.3 The Mass Balance 11.4 The Choice of Indicators 22 About the Electricity Industry2.1 History of Electricity 32.2 Electricity Generation 43 The International Electricity Market3.1 World wide Generation 73.2 World wide Consumption 103.3 World wide CO 2 Emissions 114 The UK Electricity Market4.1 UK Generation 144.2 The Structure of the Electricity Industry in the United Kingdom 174.3 Electricity Consumption in the UK 174.4 UK CO 2 Emissions 185 The Use of Coal to Generate Electricity5.1 What is Coal? 195.2 The use of Coal for Generating Electricity 206 The Use of Oil to Generate Electricity6.1 What is Oil? 236.2 The use of Oil for Generating Electricity 246.3 Generating Electricity using Oil 287 The Use of Gas to Generate Electricity7.1 What is Gas? 277.2 The use of Gas for Generating Electricity 287.3 Generating Electricity using Gas 298 The Use of Nuclear Power to Generate Electricity8.1 What is Nuclear Power? 318.2 The use of Uranium for Generating Electricity 338.3 Generating Electricity using Nuclear Power 349 The Use of Air and Water to Generate Electricity9.1 The use of Air in the Combustion Process 379.2 The use of Water in the Combustion Process 38


10 Emissions Page10.1 Solid Emissions 3910.2 Liquid Emissions 4010.3 Gaseous Emissions 4411 The Electricity Generation Mass Balance11.1 Introduction 4711.2 Key Assumptions and Reference Data 4711.3 Using the Overall Electricity Generation Mass Balance 5012 The Use of Emerging Technologiesfor Renewable Energy12.1 Combined Heat and Power (CHP) 5112.2 Fuel Cells 5312.3 Micro-turbines 5512.4 Solar Cells 5712.5 Stirling Engines 5912.6 Wave and Tidal Energy 6112.7 Wind Energy 6212.8 Market Evaluation 6312.9 Other Problems 6612.10 Legislation 6613 The Role of Effective Energy Efficiency13.1 The Role of the Government 6713.2 The Role of Industry 6813.3 The Role of the Power Producers 6813.4 The Role of the Individual 6813.5 Energy Efficiency in the UK 6913.6 Energy Efficiency Assessment1990 to 2000 7014 Current Legislation14.1 The Utilities Act 2000 7115 The Future15.1 The Energy System in 2020 7315.2 Alternative Technology Solutions 7416 Conclusions and Recommendations 7517 References 771011121314151617


1This document sets out the key findings, conclusions andrecommendations of the Biffaward Electricity GenerationMass Balance project.The Electricity GenerationMass Balance1.1 IntroductionThe report sets out the total material resource requirement of the electricity generationindustry and identifies the wastes and emissions associated with the industry.Information is presented as total mass (volume), and also as mass (volume)/kWh.This is further broken down into the four main electricity generation methods, namely,through the use of coal, oil, gas and nuclear power. The main recommendations are onthe mass balance, information can be applied to the other Biffaward mass balanceseither completed or underway.Information is also provided, in some detail, on the generation of electricity, the differentmethods, their associated emissions and wastes, and wherever possible a comparisonis made between the UK and international situations. Regulatory influences are alsoexamined, as is the market for renewable energy sources.Wherever practical, existing definitions and classifications have been adopted toassist with the identification and categorisation, in order to maintain transparency andfacilitate comparison with other electricity generation analyses.1.2 The ElectricityGeneration IndustryThe electricity generation industry has beendefined as that industry, which is involvedin the generation of electricity at powerstations, located within the United Kingdom.Material flows are therefore concerned solelywith the flow into and out of the differentpower stations, albeit in terms of the overallefficiency of the electricity generationprocess, account is made for transmissionlosses to the point of use.No consideration has been made for energyconsumption or material losses in thetransport of material to the power stationsetc. A number of studies have alreadyquantified this. 1.11.3 The Mass BalanceThe underlying principle of a ‘mass balance’is the physical law that within a closed systemthe total mass is constant.This states that while there may be amovement of mass or a transformation ofmass to different forms, for example solid togas, it cannot be created or destroyed.The purpose of a ‘mass balance’ is thereforeto ‘balance’ the masses of all inputs to anactivity with the outputs from an activity.Further details of the mass balance approachto resource has been produced by Forum forthe Future. 1.21


1.4 The Choice of IndicatorsThe World Business Council for SustainableDevelopment has identified a limited set of‘eco-efficiency’ indicators, which it proposesall companies could use for measuring theirenvironmental performance. 1.3Some of these equate directly as indicators,others are more indirect.The selected indicators are as follows:●●●●●Annual material andproduct consumption.Material and product consumptionper kilowatt-hour.Water consumption and usage.Greenhouse gas and ozonedepleting substances emissions.Waste.The greenhouse gas and ozone depletingsubstance emissions identified for this studyare as following;Water lost to steam●●●●●●●●●●CO2 *COCH4 *NMHCSOXPM10BenzopyreneHClHgRn & Ra(carbon dioxide)(carbon monoxide)(methane)(non-methane hydrocarbons)(sulphur oxides)(particulate materials)(hydrogen chloride)(mercury)(radon andother Radionucleides)1.5 The Structure of this ReportThe report is presented in 16 chapters as follows.Chapter 1: The Electricity IndustryMass BalanceChapter 9: The Use of Air and Water toGenerate Electricity.Chapter 2: About the Electricity Industry.A brief history of theelectricity industry.Defining what electricity is.The generation and usesof electricity.Chapter 3: The InternationalElectricity Market.Worldwide generation,consumption andgaseous emissions.Chapter 4: The UK Generating Industry.Key facts and figures.Chapter 5: The Use of Coal toGenerate Electricity.Chapter 6: The Use of Oil toGenerate Electricity.Chapter 7: The Use of Gas toGenerate Electricity.Chapter 8: The Use of Nuclear Power toGenerate Electricity.Chapter 10: EmissionsChapter 11: The Electricity GenerationMass BalanceChapter 12: The Use of EmergingTechnologies forRenewable EnergyChapter 13: The Role of EffectiveEnergy EfficiencyChapter 14: Current and Pending LegislationChapter 15: The FutureChapter 16: Conclusions andRecommendationsFurther supporting information is given in theAppendices to this report.Appendix 1: GlossaryAppendix 2: Definitions and terminologypertaining to the Electricity IndustryAppendix 3: ReferencesThe gasses marked * are part of the‘basket of emissions’ against whichreduction targets were agreed at theThird Conference of the Parties of theUnited Nations Framework Conventionon Climate Change in Kyoto, Japan,1 December 1997 (United Nations, 1997).2


2This chapter looks at the discovery and study of electricityand the development of the electricity generation industry.About the Electricity IndustryAlessandro VoltaHeinrich Rudolf Hertz2.1 History of ElectricityThe fact that amber acquires the power toattract light objects when rubbed may havebeen known to the Greek philosopher Thalesof Miletus, who lived about 600 BC.Another Greek philosopher, Theophrastus, ina treatise written about three centuries later,stated that other substances possess thispower. The first scientific study of electricaland magnetic phenomena, however, did notappear until AD 1600, when the Englishphysician William Gilbert published hisresearch. Gilbert was the first to apply theterm electric (Greek elektron, “amber”) tothe force that such substances exert afterrubbing. He also distinguished betweenmagnetic and electric action. 2.1The first machine for producing an electriccharge was described in 1672 by theGerman physicist Otto von Guericke.It consisted of a sulphur sphere turned by acrank on which a charge was induced whenthe hand was held against it. The Frenchscientist Charles Francois de Cisternay DuFay was the first to make clear the twodifferent types of electric charge: positiveand negative. The earliest form of condenser,the Leyden jar, was developed in 1745.It consisted of a glass bottle with separatecoatings of tinfoil on the inside and outside.If either tinfoil coating was charged from anelectrostatic machine, a violent shock couldbe obtained by touching both foil coatings atthe same time.Benjamin Franklin spent much time inelectrical research. His famous kiteexperiment proved that the atmosphericelectricity that causes the phenomena oflightning and thunder is identical with theelectrostatic charge on a Leyden jar.Franklin developed a theory that electricity isa single “fluid” existing in all matter, and thatits effects can be explained by excesses andshortages of this fluid.In c1766 the law that the force betweenelectric charges varies inversely with thesquare of the distance between the chargeswas proved experimentally by the Britishchemist Joseph Priestley. Priestley alsodemonstrated that an electric chargedistributes itself uniformly over the surface ofa hollow metal sphere, and that no chargeand no electric field of force exists withinsuch a sphere. Charles Augustin deCoulomb invented a torsion balance tomeasure accurately the force exerted byelectrical charges. With this apparatus heconfirmed Priestley’s observations andshowed that the force between two chargesis also proportional to the product of theindividual charges. Faraday, who made manycontributions to the study of electricity in theearly 19th century, was also responsible forthe theory of electric lines of force.The Italian physicists Luigi Galvani andAlessandro Volta conducted the firstimportant experiments in electrical currents.Galvani produced muscle contraction in thelegs of frogs by applying an electric currentto them. Volta in 1800 announced the firstartificial electrochemical source of potentialdifference, a form of electric battery.The fact that a magnetic field exists aroundan electric current flow was demonstrated bythe Danish scientist Hans Christian Oerstedin 1819, and in 1831 Faraday proved thata current flowing in a coil of wire canelectromagnetically induce a current in anearby coil. About 1840 James PrescottJoule and the German scientist HermannLudwig Ferdinand von Helmholtzdemonstrated that electric circuits obeythe law of the conservation of energy andthat electricity is a form of energy.An important contribution to the study ofelectricity in the 19th century was the workof the British mathematical physicist JamesClerk Maxwell, who investigated theproperties of electromagnetic waves andlight and developed the theory that the twoare identical.His work paved the way for the Germanphysicist Heinrich Rudolf Hertz, whoproduced and detected electric waves in the3


atmosphere in 1886, and for the Italianengineer Guglielmo Marconi, who in 1896harnessed these waves to produce the firstpractical radio signalling system.The Dutch physicist Hendrik Antoon Lorentzfirst advanced the electron theory, which isthe basis of modern electrical theory, in1892. The American physicist RobertAndrews Millikan first accurately measuredthe charge on the electron in 1909.From Faraday’s experiment developmentshappened at a fast rate. The race was on todevelop generators that could be of industrialuse. As a new source of energy its fullpotential was not realised. A lot ofdevelopment went into electric motors andlighting. This was in strong competition withthe well established steam engines and gaslighting. This initially caused much mistrustand rejection of electricity’s possibilities.Claims were made of the harmful effects ofusing electricity; causing headaches, skindisorders and the onset of allergies.Most of this negative feeling came fromthe gas and steam industries. They wererealising that electricity was going to providestiff competition.There were many private companies that setup to provide electric lighting for streets,theatres and galleries but by 1881, 14 yearsafter Faraday’s death, Godalming becamethe first town to combine public and privateuse of electricity. 2.2 The town councilconsidered electricity as an alternative to gaswhen their contract for gas lighting expired.What probably swayed their opinion was thatwhen the gas and electric contractorsoffered their quotes to light the town for1 year the electric bid was £195, £15 lessthan the gas bid. The source of power forthe generator was one of the waterwheelsat a local leather dressing mill, half a milefrom the town centre.The next year was an important one in thehistory of electricity generation with the birthof purpose built power stations. On the 12thof January Thomas Edison opened the‘Edison Electric Light Station’ at no. 57Holborn Viaduct. Soon after, on the 27th ofFebruary, the Hammond Electric LightCompany opened the Brighton powerstation, which claims to be the firstpermanent and viable public power supply.For consumers of electricity the importantyear was 1884. Various metering systemswhere introduced and charging began.The usual cost would be 1/2d per lamp hour.By 1892 it was realised that electricity couldbe used for heating and two years later itwas possible to ‘cook electric’. In 1918electric washing machines became availableand in the next year the refrigeratorappeared. By this time electricity had beenaccepted as the energy of the future and theword was getting around, everyone wantedelectricity. The dream of electricity for all inEngland, Scotland and Wales did not start tobe realised until the middle of 1928 whenconstruction on a national grid systembegan. It took 17 years before thesystem was in operation. Even then that didnot include the north east of England.On the 13th August 1947 the ‘Electricity Bill’received the Royal assent and the electricitysupply of England, Wales and SouthernScotland came under Public ownership.Under this new ownership, on the 17th ofOctober 1956, the world’s first large-scaleNuclear power station opened at Calder Hallin Cumbria, although its primary purposewas to produce Plutonium for military use.On the 1st of January 1958 the ElectricityAct 1957 came into effect and the CentralElectricity Generating Board (C.E.G.B.) wasset up. This situation remained until 1990when the electricity supply was privatisedand National Power, PowerGen and NuclearElectric were formed.2.2 Electricity GenerationThe production of bulk electric power isfor industrial, residential, and rural use.Electric power generation generally implieslarge-scale production of electric power instationary plants designed for that purpose.The generating units in these plants convertenergy from falling water, coal, natural gas,oil, and nuclear fuels to electric energy.Electric power generating plants are normallyinterconnected by a transmission anddistribution system to serve the electric loadsin a given area or region.An electric load (or demand) is the powerrequirement of any device or equipment thatconverts electric energy into light, heat, ormechanical energy, or otherwise consumeselectric energy as in aluminium reduction,other power requirements of electronic andcontrol devices. The total load on any powersystem is seldom constant; rather, it varieswidely with hourly, weekly, monthly, or annualchanges in the requirements of the areaserved. The minimum system load for agiven period is termed the “base loadcomponent”. Maximum loads, resultingusually from temporary conditions, are calledpeak loads, and the operation of thegenerating plants must be closelyco-ordinated with fluctuations in the load.The peaks, usually being of only a few hours’duration are frequently served by gas or oilcombustion-turbine or pumped-storagehydro generating units.4


The pumped-storage type utilises the mosteconomical off-peak (typically 10pm to 7am)surplus generating capacity to pump andstore water in elevated reservoirs to bereleased through hydraulic turbine generatorsduring peak periods. This type of operationimproves the capacity factors or relativeenergy outputs of base-load generating unitsand hence their economy of operation.A study of annual load graphs and forecastsindicates the rate at which new generatingstations must be built; they are aninseparable part of utility operation and arethe basis for decisions that profoundly affectthe financial requirements and overalldevelopment of a utility.Generating Unit SizesThe size and capacity of electric utilitygenerating units varies widely, dependingupon type of unit; duty required, that is,base-, intermediate-, or peak-load service;and system size and degree ofinterconnection with neighbouring systems.Power Plant Circuits:Both main and accessory circuits in powerplants can be classified as follows:1 Main power circuits to carry the powerfrom the generators to the step-uptransformers and on to the stationhigh-voltage terminals.2 Auxiliary power circuits to providepower to the motors used to drivethe necessary auxiliaries.3 Control circuits for the circuit breakersand other equipment operated fromthe plant’s control room.4 Lighting circuits for the illumination ofthe plant and to provide power forportable equipment required in theupkeep and maintenance of the plant.Sometimes special circuits areinstalled to supply the portablepower equipment.5 Excitation circuits, which are so installedthat they will receive good physical andelectrical protection because reliableexcitation is necessary for the operationof the plant.6 Instrument and relay circuits to providevalues of voltage, current, kilowatts,reactive kilovoltamperes,temperatures, pressures, flow rates,and so forth, and to serve theprotective system.7 Communication circuits for both plantand system communications.Telephone, radio, transmission-linecarrier, and microwave radio maybe involved.It is important that reliable power serviceis provided for the plant itself, and for thisreason station service is usually suppliedfrom two or more sources. To ensureadequate reliability, auxiliary power suppliesare frequently provided for start-up,shutdown, and communications services.Generator ProtectionNecessary devices are installed to preventor minimise other damage in cases ofequipment failure. Using differential-currentand ground relays, over-current relays andloss-of-excitation relays, the generator isimmediately de-energised for electricalfailure and shut down for any over-limitcondition, all usually automatically.Voltage RegulationThis term is defined as the change in voltagefor specific change in load (usually from fullload to no load) expressed as percentage ofnormal rated voltage.Generation ControlComputer-assisted (or on-line controlled)load and frequency control and economicdispatch systems of generation supervisionare being widely adopted, particularly for thelarger new plants.5


Synchronisation of GeneratorsSynchronisation of a generator to a powersystem is the act of matching, over anappreciable period of time, the instantaneousvoltage of a power system of one or oreother generators (running source), thenconnecting them together.Fossil Fuel PlantsFossil fuels are of plant or animal originand consist of hydrogen and carbon(hydrocarbon) compounds. The mostcommon fossil fuels are coal, oil, andnatural gas.The less common ones include peat,oil shale, and biomass (wood and so forth),as well as various waste or by-productssuch as steel mill blast furnace gas,coke-oven gas, and refuse-derived fuels.Fossil fuel electric power generation usesthe combustion heat energy from thesefuels to produce electricity.Steam Power PlantsA fossil fuel steam plant operation essentiallyconsist of four steps:(1) Water is pumped at high pressureto a boiler, where(2) it is heated by fossil-fuel combustion toproduce steam at high temperatureand pressure.(3) This steam flows through a turbine,rotating an electric generator(connected to the turbine shaft) whichconverts the mechanical energyto electricity.(4) The turbine exhaust steam iscondensed by using cooling water froman external source to remove the heatrejected in the condensing process.The condensed water is pumped backto the boiler to repeat the cycle.A given power plant’s size is determined bythe utility company’s need for power asdictated by the electrical demand growthforecast. A typical large fossil-fuel powerplant consists of several major facilities andequipment, including fuel handling andprocessing, boiler (including furnace), turbineand electric generator, condenser andcondenser heat removal system, feed waterheating and pumping system, flue gascleaningsystem, and plant controls andcontrol system.Gas Turbine PlantsPower plants with gas turbine-driven electricgenerators are often used to meet short-termpeaks in electrical demand. Gas turbinepower plants use atmospheric air as theworking medium, operating on an open cyclewhere air is taken from and discharged tothe atmosphere and is not recycled. In asimple gas turbine plant, air is compressedand fuel is injected into the compressed airand burned in a combustion chamber.Variations of this basic operation to increasecycle efficiency include regeneration, whereexhaust from the turbine is used to preheatthe compressed air before it enters thecombustion chamber.Hydroelectric PlantsHydroelectric operation is an attractivesource of electric power because it is arenewable resource and a non-consumptiveuse. In the broadest sense, hydroelectricpower is a form of solar power; the resourceis renewed by the solar cycle in which wateris evaporated from the oceans, transportedby clouds, and falls as precipitation on thelandmasses. It then returns through rivers tothe ocean, generating power on the way.Hydroelectric power can be defined as thegeneration of electricity by flowing water;potential energy from the weight of waterfalling through a vertical distance isconverted into electrical energy.Power FailuresIn most parts of the world, local or nationalelectric utilities have joined in grid systems.The linking grids allow electricity generatedin one area to be shared with others.Each pooling company gains an increasedreserve capacity, use of larger, moreefficient generators, and compensation,through sharing, for local power failures.These interconnected grids are large,complex machines that contain elementsoperated by different groups. These complexsystems offer the opportunity for economicgain, but increase the risk of widespreadfailure. For example, a major grid-systembreakdown occurred on November 9, 1965,in eastern North America, when anautomatic control device that regulates anddirects current flow failed in Queenston,Ontario, causing a circuit breaker to remainopen. A surge of excess current wastransmitted through the northeastern UnitedStates. Generator safety switches fromRochester, New York, to Boston,Massachusetts, were automatically tripped,cutting generators out of the system toprotect them from damage. Powergenerated by more southerly plants rushedto fill the vacuum and overloaded theseplants, which automatically shut themselvesoff. The power failure enveloped an area ofmore than 200,000 sq. km (80,000 sq.miles), including the cities of Boston, Buffalo,Rochester, and New York. Similar gridfailures, usually on a smaller scale, havetroubled systems in North America andelsewhere. In some areas the outage lasted25 hours as restored high voltage burned outequipment. These major failures are termedblackouts. The term brownout is often usedfor partial shutdowns of power, usuallydeliberate, either to save electricity or as awartime security measure. To protectthemselves against power failures, hospitals,public buildings, and other facilities thatdepend on electricity have installedbackup generators.Voltage RegulationLong transmission lines have considerableinductance and capacitance as well asresistance. When a current flows through theline, inductance and capacitance have theeffect of varying the voltage on the line asthe current varies. Thus the supply voltagevaries with the load. Several kinds of devicesare used to overcome this undesirablevariation, in an operation called regulation ofthe voltage. They include induction regulatorsand three-phase synchronous motors (calledsynchronous condensers), both of whichvary the effective amount of inductance andcapacitance in the transmission circuit.Inductance and capacitance react with atendency to nullify one another. When a loadcircuit has more inductive than capacitivereactance, as almost invariably occurs inlarge power systems, the amount of powerdelivered for a given voltage and current isless than when the two are equal. The ratioof these two amounts of power is called thepower factor. Because transmission-linelosses are proportional to current,capacitance is added to the circuit whenpossible, thus bringing the power factor asnearly as possible to 1. For this reason, largecapacitors are frequently inserted as a partof power-transmission systems.6


3This chapter gives a brief overview of the internationalelectricity generation market, while chapter 4 focuses on theUK generation capabilityThe InternationalElectricity Market3.1 World wide GenerationBillion Killowatthours35,00030,00025,00020,00015,00010,0005,0000Table 3-1World Net Electricity Consumptionin 3 Cases from 1970 to 2025HistoryProjectionsHigh EconomicGrowthReferenceLow EconomicGrowth1970 1980 1990 2001 2010 2025In the International Energy Outlook 2003 3.1(IEO2003) reference case, world wideelectricity consumption is projected toincrease at an average annual rate of2.4% from 2001 to 2025.The most rapid projectedgrowth in electricity use byregion is 3.7% per year fordeveloping Asia, whererobust economic growth isexpected to increasedemand for electricityto run newly purchasedhome appliancesfor air conditioning,refrigeration, cooking,space and water heating.By 2025, developing Asia as awhole is expected to consumealmost 2.5 times as much electricityas it did in 2001. In China, electricityconsumption is projected to grow by anaverage of 4.3% per year, nearly tripling overthe forecast period.In Central and South America, as indeveloping Asia, high rates ofeconomic growth are expected toFigure 3-2World Energy Consumption for Electricity Generationimprove standards of living andincrease electricity use forindustrial processes and in21%7%homes and businesses.19%The expected growthrate for electricity use in19%Central and South34%America is 3.3% peryear. In Brazil,the region’s largesteconomy and largestoilnatural gascoalnuclearrenewablesconsumer of electricity,electricity consumption isprojected to increase by3.2% per year, withelectrification coming to ruralpopulations that previously have nothad access to the National Grid.Electricity consumption in the industrialisedworld is expected to grow at a more modestpace than in the developing world, at 1.7%per year. In addition to expected slowergrowth in population and economic activityin the industrialised nations, marketsaturation and efficiency gains for someelectronic appliances are expected to slowthe growth of electricity consumption fromhistorical rates.There have been two importantdevelopments in the electricity sector inrecent years that may affect the way theindustry works in the future. The first isthe increasing role of foreign investmentin the developing regions of the world.Greater access to foreign investment in theelectricity sector had allowed developingnations to construct the infrastructureneeded for substantial increases in accessto electricity.A second important development iselectricity reform. Many developing countrieshave implemented reforms to the rulesgoverning electricity generation anddistribution in an effort to secure the directforeign investment they need to moderniseand improve the electricity infrastructure.In industrialised countries many nations haveundertaken electricity reforms to introducegreater competition in domestic markets inan effort to reduce the cost of electricity toconsumers. These two factors are drivingthe changes in the electricity sector and areexpected to have a profound effect in thedevelopment of the electricity industry overthe next two decades.7


Table 3-1World Energy Consumption for Electricity Generation by Region and Fuel, 2000-2025(Quadrillion Btu)HistoryProjectionsRegion and Fuel 2000 2001 2005 2010 2015 2020 2025Industrialized 89 89.6 92.1 99.9 106.4 113.3 120.1Oil 5.0 4.9 4.5 4.6 5 5.2 5.5Natural Gas 14.3 14.7 16.6 19.4 23.5 28.4 33.5Coal 30.5 30.9 32.3 34.8 35.4 36.1 37.7Nuclear 22.6 22.4 21.6 22.3 22.4 21.9 20.4Renewables 16.5 16.7 17.2 18.9 20 21.7 23EE/FSU 23.2 22.6 20.6 22.8 25.3 26.3 27Oil 1.5 1.3 0.4 0.5 0.9 1.2 0.8Natural Gas 7.9 8 8.5 9.5 12 13.7 16.1Coal 6.3 6 4.9 4.1 3.6 2.7 1.6Nuclear 4.3 4.1 3.2 3.3 3.3 3 2.6Renewables 3.2 3.2 3.6 5.5 5.6 5.7 5.8Developing 39.8 41.2 47 55 64.1 74.1 85Oil 5 5.3 6.2 6 6.8 7.6 8.2Natural Gas 6.3 6.5 7.2 9.8 13.4 16.7 21.0Coal 14.4 15.1 18.1 21.4 23.8 28.3 32.7Nuclear 2.6 2.7 2.7 3.1 4.2 4.5 5.0Renewables 11.4 11.7 12.8 14.6 15.9 17.0 18.0Total World 151.9 153.4 159.7 177.7 195.7 213.7 232Oil 11.6 11.5 11.1 11.1 12.7 14.0 14.5Natural Gas 28.4 29.2 32.3 38.7 48.8 58.9 70.6Coal 51.2 52 55.2 60.3 62.9 67.1 72.0Nuclear 29.5 29.1 27.5 28.7 29.8 29.4 28.0Renewables 31.1 31.6 33.5 38.9 41.5 44.4 46.93.1.1 Primary Fuel Use for ElectricityGenerationThe mix of primary fuels used to generateelectricity has changed a great deal over thepast three decades on a world wide basis.Coal has remained the dominant fuel,although electricity generation from nuclearpower increased rapidly from the 1970sthrough the mid-1980s, and natural-gas-firedgeneration has grown rapidly in the 1980sand 1990s. In contrast, in conjunction withthe high world oil prices brought on by the oilprice shocks resulting from the OPEC oilembargo of 1973-1974 and the IranianRevolution of 1979, the use of oil forelectricity generation has been slowing sincethe mid-1970s. In the IEO2003 referencecase, continued increases in the use ofnatural gas for electricity generation areexpected world wide. Coal is projected tocontinue to retain the largest market share ofelectricity generation, but its importance isexpected to be diminished somewhat by therise in natural gas use. The role of nuclearpower in the world’s electricity markets isprojected to lessen as reactors inindustrialised nations reach the end of theirlife spans and few new reactors areexpected to replace them. Generation fromhydropower and other renewable energysources is projected to grow by 56% overthe next 24 years, but their share of totalelectricity generation is projected to remainnear the current level of 21%.19%Natural GasElectricity markets of thefuture are expected todepend increasingly on natural gas-firedgeneration. Industrialised nations are intentupon using combined-cycle gas turbines,which usually are cheaper to construct andmore efficient to operate than other fossilfuel-firedgeneration. Natural gas is also seenas a much cleaner fuel than other fossil fuels.World wide, natural gas use for electricitygeneration is projected to be almost 2.5times greater in 2025 than it was in 2001 astechnologies for natural-gas-fired generationcontinue to improve and ample gas reservesare exploited. In the developing world,natural gas is expected to be used todiversify electricity fuel sources, particularlyin Central and South America, where heavyreliance on hydroelectric power has led toshortages and blackouts during periods ofsevere drought.The former Soviet Union (FSU) accounted formore than one-third of natural gas usage forelectricity generation world wide in 2001,and natural gas provided 42% of the energyused for electricity generation in the FSU.By 2025, natural gas is projected to accountfor 63% of the electricity generation marketin the FSU. Relying increasingly on importsfrom Russia, the nations of Eastern Europeare also expected to increase their use ofnatural gas for electricity generation, from a9% share of total generation in 2001 to 50%in 2025.In North America, the natural gas share ofthe electricity fuel market in the United Statesis projected to increase from 18% in 2001to 24% in 2025, with Canadian exportsexpected to provide a growing supply ofnatural gas to US generators. The naturalgas share of electricity generation in Canadais also projected to grow, from 3% in 2001to 11% in 2025. Natural gas consumption forelectricity generation in Western Europe isprojected to nearly triple over the forecastperiod, and its share of the region’s electricityfuel market is projected to grow from 17%in 2001 to 38% in 2025 as the nuclearpower and coal shares are reduced.After the oil crisis of 1973, European nationsactively discouraged the use of natural gasfor electricity generation (as did the UnitedStates) and instead favoured domestic coaland nuclear power over dependence onnatural gas imports. The EuropeanCommission’s 1975 directive, 75/404/EECrestricted the use of natural gas in newpower plants.The natural gas share of the electricitymarket in Western Europe fell from 9%in 1977 to 5% in 1981, where it remainedfor most of the 1980s. In the early 1990s,the growing availability of reserves from theNorth Sea and increased imports fromRussia and North Africa lessenedconcerns about gas supply in the region,and the EU directive was repealed. In Centraland South America natural gas accountedfor 9% of the electricity fuel market in 2001.Its share is projected to grow to 46% in2025. Hydropower is the major sourceof electricity supply in South America atpresent, but environmental concerns,cost overruns on large hydropowerprojects in the past, and electricity shortfallsduring periods of drought have promptedSouth American8


governments to view natural gas as a meansof diversifying their electricity supplies.A continent-wide natural gas pipeline systemis being built in South America, which willtransport Argentine and Bolivian gas to Chileand Brazil.Per capita consumption of natural gasin Asia and Africa is relatively small whencompared with Europe and North America.In 2001, Japan accounted for one-fourth ofnatural gas consumption in Asia. Almost allnatural gas consumed in Japan is importedas liquefied natural gas (LNG). Japan isexpected to maintain its dependenceon natural gas at around 20% of theelectricity fuel market through 2025.34%CoalIn 2025, coalis expectedto account for 31% of the world’s electricityfuel market, slightly lower than its 34% sharein 2001. The United States accounted for40% of all coal use for electricity generationin 2001, and China and India togetheraccounted for 27%.In the IEO2003 forecast, the coal share ofUS electricity generation is expected toremain at roughly 50% through 2025.China’s coal share is projected to rise slightly,to 73% in 2025 from 72% in 2001. Over thesame period, coal’s share of India’s electricitymarket is expected to decline from 72%to 63%.Although coal remains a relatively cheapsource of electricity production, natural gas isviewed as being environmentally superior,and the economics of natural gas generationtechnology are improving, particularly incountries with access to gas pipelines.Reliance on coal for electricity generationis also expected to be reduced in otherregions. In Western Europe, for example,coal accounted for 20% of the electricityfuel market in 2001 but is projected tohave only a 12% share in 2025.Similarly, in Eastern Europe and the FSU(EE/FSU), coal’s 27% share of theelectricity fuel market in 2001 is projectedto fall to 6% in 2025. For years,massive state subsidies were all that keptmany coal mines operating in Western andEastern Europe. In many cases, electricityconsumers underwrote the subsidies.The EU has adopted policy measures toeliminate or reduce state subsidies fordomestic coal production, and only four EUmember states (the United Kingdom,Germany, Spain, and France) continue toproduce hard coal.19%Nuclear PowerThe nuclear share ofenergy use for electricityproduction is expected to decline in mostregions of the world as a result of publicopposition, waste disposal issues, concernsabout nuclear arms proliferation, and theeconomics of nuclear power. The nuclearshare of electricity generation world wide isprojected to drop to 12% in 2025 from 19%in 2001.In the United States, the nuclear share isprojected to decline from 19% of theelectricity fuel market in 2001 (secondbehind coal) to 15% in 2025.In Canada, where the nuclear share ofthe market has been declining since 1984,its 22% share in 2001 is projected to fall to11% in 2025. In Western Europe, whereFinland is the only country projected to buildnew nuclear units, the nuclear share of theregion’s electricity fuel market is projected tofall from 34% in 2001-more than any otherenergy source-to 21% in 2025.In Japan, nuclear power accounted for 39%of the energy used for electricity generationin 2001. That share is expected to decline to31% by 2025 in the IEO2003 forecast. In theEE/FSU region, the nuclear share is projectedto decline from 18% in 2001 to10% in 2025. Nuclear powercontributes very little to electricity generationin the developing nations of Central andSouth America, Africa, and the Middle East,and it is expected to contribute little in 2025.In Central and South America, only Argentinaand Brazil were nuclear power producers in2001. In Africa, only South Africa generatedelectricity from nuclear power in 2001.There are no nuclear power plants inoperation in the Middle East, although twoare under construction in Iran.In contrast to the rest of the world’s regions,in developing Asia nuclear power isexpected to play a growing role in electricitygeneration. China, India, Pakistan,South Korea, and Taiwan currently havenuclear power programs, and the nuclearshare of the region’s electricity fuel marketis expected to remain stable at roughly9% from 2001 through 2025. China isexpected to account for most of the region’snuclear power capacity additions.7%OilThe role of oil in the world’s electricitygeneration market has been on the declinesince the 1979 oil price shock. Oil accountedfor 23% of electricity fuel use in 1977,in 2001 its share stood at 7%.Energy security concerns, as well asenvironmental considerations, have alreadyled most nations to reduce their use of oil forelectricity generation. In regions where oilcontinues to hold a significant share of thegeneration fuel market, such as the FSU andthe Middle East, it generally is expected tomaintain its position. As a result, the oil shareof world energy use for electricity productionis projected to remain stable at between6 and 7% through 2025. Developing Asiaaccounted for 18% of the world’sconsumption of oil for electricity generationin 2001, when 7% of its electricity fuel useconsisted of oil down from 29% in 1977).The oil share of electricity fuel consumptionin developing Asia is expected remain stablethrough 2025. In the petroleum-rich MiddleEast, oil supplied 38% of the energy usedfor electricity generation in 2001, and itsshare is projected to decline slightly,to 34% in 2025.21%Hydroelectricity andOther RenewablesRenewable energy, predominantlyhydropower, accounted for one-fifth of theworld’s energy use for electricity generationin 2001, where it is expected to remainthrough 2025. Of the world’s consumptionof renewable energy for electricity productionin 2001, the United States and Canadatogether accounted for almost 29%of the total, Western Europe for 20%,and Central and South America 19%(despite consuming just 5 percent of theworld’s electricity). In 2001, renewablesaccounted for 9% of electricityproduction in the United States and56% in Canada, both nations wherehydroelectric power has been extensivelydeveloped. Their shares are expected togrow slightly by 2025. In North Americaand throughout the world, generation9


technologies using non-hydroelectricrenewables are expected to improve overthe forecast period, but they still areexpected to be relatively expensive in the lowprice environment assumed for energy fuelsin the IEO2003 reference case.Hydroelectricity is used the most forelectricity generation in Central and SouthAmerica, and renewables accounted for73% of the region’s electricity fuel marketin 2001. Recent experiences with drought,cost overruns, and the negativeenvironmental impacts of several large-scalehydroelectric projects have reduced theappeal of hydropower in South America.The renewable share of electricitygeneration in the region is expected todecline to 45% by 2025 as countries workto diversify their electricity fuel mix.Most of Western Europe’s renewable energyconsumption consists of hydroelectricity.Renewables in total accounted for 24%of the region’s electricity market in 2001,and their share is expected to increase to25% by 2025. Some European nations,particularly Denmark and Germany, areactively developing their non-hydroelectricrenewable energy resources, mostnotably wind.Some near-term growth in renewableenergy use is expected in developing Asia,particularly in China, where the 18,200-megawatt Three Gorges Dam and anumber of other major hydropower projectsare expected to become operational duringthe forecast period. Developing Asia reliedon renewables for 18% of its electricityproduction in 2001, and that share isexpected to shrink slightly, to 16%in 2025.3.2 World Wide ConsumptionThe IEO2003 reference case projectsthat consumption of every primary energysource will increase over the 24-yearforecast horizon. Much of the increment infuture energy demand in the reference caseis projected to be for fossil fuels (oil, naturalgas, and coal), because it is expected thatfossil fuel prices will remain relatively low,and that the cost of generating energy fromother fuels will not be competitive. It ispossible, however, that as environmentalprograms or government policies –particularly those designed to limit or reducegreenhouse gas emissions –are implemented, the outlook might change,and non-fossil fuels (including nuclear powerand renewable energy sources such ashydroelectricity, geothermal, biomass,solar, and wind power) might become moreattractive. The IEO2003 projections assumethat government policies or programs in placeas of October 1, 2002 will remain constantover the forecast horizon.Oil is expected to remain the dominantenergy fuel throughout the forecast period,with its share of total world energyconsumption falling only slightly from39% in 2001 to 38% in 2025.In the industrialised world, increases inoil use are projected primarily in thetransportation sector, where there arecurrently no available fuels to competesignificantly with oil products.The IEO2003 reference case projectsdeclining oil use for electricity generation,with other fuels (especially natural gas)expected to be more favourable alternativesto oil-fired generation. In the developingworld, oil consumption is projected toincrease for all end uses. In some countrieswhere non-commercial fuels have beenwidely used in the past such as fuel woodfor cooking and home heating), dieselgenerators are now sometimes being used todissuade rural populations from decimatingsurrounding forests and vegetation. This ismost notably in Sub-Saharan Africa, Centraland South America, and Southeast Asia.Because the infrastructure necessary toexpand natural gas use has not been aswidely established in the developing world asit has in the industrialised world, natural gasuse is expected to grow in the developingworld, but not enough to accommodate all ofthe increase in demand for energy.Natural gas is projected to be the fastestgrowing primary energy source world wide,maintaining growth of 2.8% annually overthe 2001-2025 period, nearly twice the rateof growth for coal use. Natural gasconsumption is projected to rise from 90trillion cubic feet in 2001 to 176 trillion cubicfeet in 2025, primarily to fuel electricitygeneration. Gas is increasingly seen as thedesired option for electric power, given theefficiency of combined-cycle gas turbinesrelative to coal- or oil-fired generation.Gas also burns more cleanly than either coalor oil, making it a more attractive choicefor countries interested in reducinggreenhouse gas emissions.Coal use world wide is projected toincrease by 2.2 billion short tons (at a rateof 1.5% per year) between 2001 and 2025.Substantial declines in coal use are projectedfor Western Europe and the EE/FSUcountries, where natural gas is increasinglybeing used to fuel new growth in electricpower generation and for other uses in theindustrial and building sectors. In thedeveloping world, however, even largerincreases in coal use are expected.The largest increases are projected for Chinaand India, where coal supplies are plentiful.Together these two countries account for86% of the projected rise in coaluse in the developing world over theforecast period.World wide, consumption of electricitygenerated from nuclear power is expected toincrease from 2,521 billion kilowatt-hours in2001 to 2,737 billion kilowatt-hours in 2025.Until very recently, nuclear electricityconsumption was expected to declinesharply by the end of the forecast.The prospects for nuclear power have beenreassessed, however, in light of the highercapacity utilisation rates reported for manyexisting nuclear facilities and the expectationthat fewer retirements of existing plants willoccur than previously projected. Furtherextensions of operating licenses (or theequivalent) for nuclear power plants areexpected to be granted among the countriesof the industrialised world, slowing thedecline in nuclear generation. In many ofthe industrialised countries, extending theoperating life of a nuclear power plant is adecision left primarily to the owner and thusis essentially a question of economic viability.In the IEO2003 reference case, world nuclearcapacity is projected to rise from 353gigawatts in 2001 to 393 gigawatts in 2015before falling to 366 gigawatts in 2025.In contrast, in last year’s IEO, world nuclearcapacity was projected to rise to 363gigawatts in 2010 and then fall to 359gigawatts in 2020.The highest growth in nuclear generation isprojected for the developing world, whereconsumption of electricity from nuclearpower is projected to increase by 4.1%per year between 2001 and 2025.In particular, developing Asia is expected tosee the greatest expansion in new nucleargenerating capacity. As of February 2003,the nations of developing Asia accountedfor 17 of the 35 reactors currently under10


construction world wide, including 8 in India,4 in China, 2 each in South Korea andTaiwan, and 1 in North Korea accountingfor 12 of the 30 gigawatts currently underconstruction. Consumption of electricity fromhydropower and other renewable energysources is projected to grow by 1.9%annually in the IEO2003 forecast. With fossilfuel prices projected to remain relatively lowin the reference case, renewable energysources are not expected to be widelycompetitive, and the renewable share oftotal energy use is not expected to increase.Over the 2001-2025 forecast horizon,renewables maintain their share of totalenergy consumption at 8%.Moreover, despite the high rates of growthprojected for alternative renewable energysources, such as wind power in WesternEurope and biomass and geothermal powerin the United States, much of the growth inrenewable energy sources will result fromlarge-scale hydroelectric power projects inthe developing world, particularly amongthe nations of developing Asia.China, India, Malaysia, and Vietnam arealready constructing or have plans toconstruct ambitious hydroelectric projectsover the projection period.3.3 World wide CO2 EmissionsWorld carbon dioxide emissions areexpected to increase by 3.8 billion metrictons carbon equivalent over current levelsby 2025-growing by 1.9% per year -if world energy consumption reachesthe levels projected in the IEO2003reference case.Billion Metric Tons Carbon Equivalent12108642Figure 3-3World Carbon Dioxide Emissionsby RegionHistoryIndustrialisedEE/FSUAccording to this projection, worldcarbon dioxide emissions in 2025 wouldexceed 1990 levels by 76%. Oil and naturalgas contribute about 1.5 and 1.3billion metric tons, respectively, to theprojected increase from 2001, and coalprovides the remaining 1.1 billion metric tonscarbon equivalent. Carbon dioxide emissionsfrom energy use in the industrialisedcountries are expected to increase by1.2 billion metric tons carbon equivalentto 4.3 billion metric tons in 2025, or byabout 1.3% per year. Emissions from thecombustion of petroleum productsaccount for more than 44% of the totalincrement expected for the industrialisedworld, and the increase in emissions fromnatural gas is expected to be more thantwice as large as that from coal.By 2020, carbon dioxide emissions in thedeveloping world (including China and India)are expected to surpass those in theindustrialised countries, even thoughdeveloping countries are projected to useless energy than industrialised countries atthat time. Total emissions in developingnations are expected to increase by 2.3billion metric tons to a total of 4.7 billionmetric tons carbon equivalent in 2025,representing about 59% of theprojected increment world wide.The sizeable rise in emissions among thedeveloping nations is partially a result of theircontinued heavy reliance on coal, the mostcarbon-intensive of the fossil fuels.Coal is used extensively in the developingAsia region, which has the highest expectedrate of economic and energygrowth in the forecast.ProjectionsDevelopingTotalCarbon dioxide emissions in developing Asiaalone are projected to increase from 1.6billion metric tons carbon equivalent in 2001to 3.3 billion metric tons in 2025. In theEE/FSU region as a whole, carbon dioxideemissions are not expected to return to theirSoviet-era levels during the projection period.This year’s reference case projection hasbeen revised to reflect the expectation thatcoal use will not decline as precipitously aswas projected in previous editions of thisreport, particularly among the FSU countries.The region appears to be in the midst ofsustained economic recovery after thepolitical, social, and economic upheavals thatfollowed the break up of the Soviet Union inthe early 1990s. Emissions are not expectedto increase as quickly as energy usebecause of gains in energy efficiencyresulting from the replacement of old,inefficient capital stock, and because inmany countries in the region natural gas isexpected to displace coal, particularly fornew electricity generation capacity.The region may also be able to takeadvantage of its lower emissions levelsshould a world wide carbon trading systembe enacted in the future.World wide, carbon dioxide emissions perperson are projected to increase from about1.1 metric tons in 1990 to 1.3 metric tonsin 2025. Per capita emissions in theindustrialised countries remain much higherthan those in the rest of the worldthroughout the projection period, increasingfrom 3.2 to 3.6 metric tons per personbetween 1990 and 2010 and then to 4.2metric tons per person in 2025 in theIEO2003 reference case. In December 2002Canada and New Zealand ratified the KyotoProtocol to the United Nations FrameworkConvention on Climate Change (UNFCCC).As of February 24, 2003, 104 countries plusthe European Community had ratified thetreaty. Thirty of the ratifying nations are theso-called Annex I countries, which arerequired to limit or reduce their greenhousegases relative to 1990 levels under the termsof the Protocol. 3.2 These 30 countriesaccounted for around 44% of the total AnnexI emissions in 1990. The Kyoto Protocolenters into force 90 days after it has beenratified by at least 55 of the parties to theUNFCCC, including a representation ofAnnex I countries accounting for at least55% of the total 1990 carbon dioxideemissions from the Annex I group.01990 2001 2010 2020 202511


Although the United States had the largestshare of Annex I emissions in 1990 at35%, even without US participation theProtocol could enter into force for othersignatories. Russia has publicly announcedplans to advance ratification of the KyotoProtocol. Because Russia accounted for17% of the 1990 Annex I carbon dioxideemissions, its ratification would bring theProtocol into force as long as Russia meetsthe Protocol’s requirements for verifyingand monitoring emissions levels.China and India also ratified the KyotoProtocol in 2002. Although both countriesaccount for significant amounts of theworld’s carbon dioxide emissions,their ratification does not affect theimplementation of the Protocol, becauseneither country is an Annex I member.In 2001, China and India together accountedfor 17% of total world carbon dioxideemissions, as compared with the 24%share made up by US emissions in 2001.In the United States, the Bush Administrationhas introduced initiatives aimed at reducinggreenhouse gas intensity as an alternative tothe Kyoto Protocol. Under the President’sClear Skies and Global Climate ChangeInitiatives, the United States will work toreduce greenhouse gas intensity by 18%by 2012. Carbon dioxide intensity is definedas the amount of carbon dioxide emitted perdollar of gross domestic product (GDP).This measurement illustrates therelationship between emissions and theexpansion of economic activity.The Administration argues that reducingthe amount of greenhouse gasesemitted per dollar of GDP will slow therate of increase in emissions withoutsacrificing needed economic growth.World carbon dioxide intensity hasimproved (decreased) substantially overthe past three decades, falling from302 metric tons carbon equivalent permillion 1997 dollars of GDP in 1970 to202 metric tons per million 1997 dollars in2001. Although the pace of improvementin emissions intensity is expected to slowover the forecast period, it still continuesto improve in the reference caseprojections, dropping to 154 metric tonsper million 1997 dollars in 2025.transitional economies ofthe EE/FSU and in Chinaand India. In the FSU,economic recoveryfrom the upheavalof the 1990s isexpected to continuethroughout theforecast. The FSUnations are alsoexpected to replaceold and inefficientcapital stock andincreasingly use lesscarbon-intensive naturalgas for new electricitygeneration and other enduses rather than the morecarbon-intensive oil and coal.Eastern European nations have beenin economic recovery longer than hasthe FSU, and natural gas is expected tocontinue to displace coal use in theregion, resulting in an average 2.8%annual improvement (decrease) incarbon intensity for Eastern Europeas a whole.In developing Asia, fairly rapidimprovements in carbon dioxide intensityare expected for China and India over theprojection period, primarily as a result ofrapid economic growth rather than aswitch to less carbon-intensive fuels.Both China and India are projected toremain heavily dependent on fossil fuels,particularly coal, in the IEO2003 referencecase, but their annual GDP growth isprojected to average 5.9%,compared with an expected 3.4%annual rate of increase in fossil fuel usefrom 2001 to 2025.Figure 3-4World Carbon Dioxide Emissions by FuelBillion Metric Tons Carbon Equivalent121086420HistoryProjections1970 1980 1990 2001 2010 20201975 1985 1995 2005 2015 2025Natural Gas Coal OilFigure 3-5World Carbon Dioxide Intensityby Selected Countries & RegionsFormer Soviet UnionChinaMiddle EastEastern EuropeIndiaAfricaSouth KoreaMexicoCanadaAustrailia/ New ZealandCentral & South AmericaUnited StatesNetherlandsUnited KingdomGermanyItalyJapanFranceOn a regional basis, the most rapidimprovements in carbon dioxide intensityare expected to occur among the200120250 200 400 600 800 1,000Metric Tons Carbon Equivalentper Million 1997 U.S. Dollars of GDP12


4This chapter gives a brief overview of the United Kingdomelectricity generation market.The UK Electricity MarketThe electricity industry in the UK plays a key role in the economy by transforming, producingand supplying electricity to all sectors. Electricity consumption has increased steadily rising from11% of the total final energy consumption in 1970 to 18% in 2000. 4.1The electricity sector contributed 1.3% to the Gross Domestic Product in 2000, and is verycapital intensive with total capital assets of approximately £35 billion.The total turnover from the sale of electricity in 2000 was £15.6 billion, with two thirds of thetotal profit, namely £3.3 billion reinvested in the business, amounting to 12% of all industrialinvestment made in the UK.On average each customer is off supply for 75 minutes a year, which equates to 99.98%availability, largely as a result of significant investment in the distribution networks sinceprivatisation. In 2001 the price paid by the UK consumer for electricity was the fourthlowest in Europe.Figure 4-1Percentage of Energy Consumedas Electricity Per SectorIndustryDomesticService Sector37%27%21%Table 4-1Electricity prices for Households,US Dollars per Kilowatthour 4.2Country 1994 1995 1996 1997 1998 1999OECD 1 0.116 0.127 0.121 0.114 0.110 n.a.OECD Europe 0.135 0.150 0.147 0.131 0.131 n.a.United Kingdom 0.122 0.127 0.125 0.125 0.121 0.117USA 2 0.084 0.084 0.084 0.084 0.083 0.0811Organisation for Economic Co-operation and Development2.Price excluding tax n.a. Not AvailableTable 4-2Electricity Prices for Industry,US Dollars per Kilowatthour 4.3Country 1994 1995 1996 1997 1998 1999OECD 1 0.073 0.079 0.074 0.068 0.063 n.a.OECD Europe 0.071 0.077 0.074 0.065 0.065 n.a.United Kingdom 0.067 0.068 0.065 0.065 0.065 0.064USA 2 0.047 0.047 0.046 0.044 0.040 0.0391Organisation for Economic Co-operation and Development2.Price excluding tax n.a. Not Available13


Table 4-3Key UK Electricity Industry FiguresGenerating capacity (MW) (1) 79,562Generation Output (GWh) (1) 385,826System load factor (%) (1) 70.8Plant load factor (%) (1) 53.1Thermal efficiency (%) (1):Conventional steam stations 35.7CCGTs 46.4Nuclear stations 37.3Maximum demand (MW)(1) 57,052Electricity supply (net) (GWh)(1) 365,241Net imports (GWh)(1) 10,399Sales of electricity (GWh) (1) 321,751Revenue from sales of electricity (£m) (1) 14,850Average revenue from sales of electricity (p/kWh)(1) 4.584Transmission network (circuit km) 25,529Units transmitted (TWh) 349Distribution network (circuit km) 808,209Units distributed (GWh) 317,460Number of customers’ (000s) 28,160Number of employees 7,240Figure 4-2Electricity Generation Methods1980 to 2000TWH6005004003002001002000199019800Coal Oil Gas Nuclear Hydro Other NetFuels Imports114.6 5.1 143.7 78.3 5.1 8.3 14.2208 21.3 1.6 58.7 11.9 - 7.9190 33.9 1.6 32.3 7.3 - 0System frequency (Hz) 50 +/- 1%System voltage (V) 230 +10% -6%Notes:1. Figures are for calendar year 2001. The difference in the amount of electricity generated versus thatsupplied is accounted for by system losses.4.1 UK GenerationIn May 2002 there were 163 power stations operating in the United Kingdom, with agenerating capacity of 73, 455 megawatts (MW). If one includes ‘other’ power stations usingrenewable or combustible wastes, and combined heat and power schemes (CHP)(see Chapter 13 for more details) the generating capacity rises to 79753 MW.Table 4-4The UK generation mixType of Capacity Percentagegeneration (MW)Coal 30272 38%Gas 24989 31%Oil 5816 7%Nuclear 12242 15%Hydro 4128 5%The main source for the generation ofelectricity in the UK is still coal, followed bygas, with nuclear power generated electricityat 15%. For more details on the generationof electricity by these different methods,see Chapters 4 to 8.The following table shows the electricityavailability by fuel type for 1980, 1990 and2000, and for the period 1998 through to2000 which has shown significant change.Figure 4-3Generating Capacity MethodChanges, 1998 to 2000TWH450400350300250200150100500200019901980Coal Oil Gas Nuclear Hydro Other NetFuels Imports114.6 5.1 143.7 78.3 5.1 8.3 14.2101.2 5.3 139.8 87.7 5.3 8.6 14.2117 5.9 116.3 90.6 5.1 7.8 12.5Other 2306 3%Total 79753 100%14


Tables detailing the number of power stations operating within the UK.73,455 (MW) Total installed capacity.UK Generation Stations275kv transmission400kv transmissionCoal firedOil firedNuclearPumped storageHydroGasCCGTDual-FiredRecyling Power StationsCoal Fired Power Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganDrax 3,870 1974Fifoots Point (2) 393 2000Ferrybridge C 1,955 1966Fiddler’s Ferry 1,961 1971Lynemouth 248 1995Eggborough 1,960 1968Aberthaw B 1,506 1971Rugeley 1,006 1972Cottam 2,008 1969West Burton 1,932 1967Ratcliffe 2,000 1968High Marnham 945 1959Ironbridge 970 1970Didcot A Coal /gas 2,040 1972Kilroot Coal/oil 520 1981Tilbury B Coal /oil 1,071 1968Kingsnorth Coal /oil 1,455 1970Nuclear Power Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganDungeness B 1,110 1985Hartlepool 1,210 1989Heysham1 1,150 1989Heysham 2 1,250 1989Hinkley Point B 1,220 1976Sizewell B 1,188 1995Hunterston B 1,190 1976Torness 1,250 1988Calder Hall 194 1956Sizewell A 420 1966Wylfa 980 1971Recycling Power Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganSuffolk Poultry litter 13 1992Thetford Poultry litter 39 1998Wolverhampton Waste 20 1994Landmann Way, London Waste 32 1994Glanford Meat & bone meal 13 1993Oil, Oil/Gas, Diesel, Diesel/GasKerosene Fired Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganIndian Queens 140 1996Coolkeeragh 293 1959Fawley 518 1969Littlebrook D 790 1982Grain 1,350 1979Ballylumford Oil/gas 1,080 1968Peterhead Oil/gas 1,550 1980Thatcham Diesel 9.6 1994Five Oaks Diesel 11.5 1995Lerwick Diesel/gas 66 1953Princetown Kerosene 3 1959Roseland Kerosene 5 196315


Combined Heat and PowerPower Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganDerwent 236 1994Fellside 168 1993CCGT Power Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganBarry 250 1998Barking 1,000 1994Kings Lynn 350 1996Peterborough 380 1993Corby 401 1993Coryton 750 2001Brimsdown 406 1999Saltend 1,200 2000Damhead Creek 792 2000Westfield Development Centre 120 1998South Humber Bank 1 785 1996South Humber Bank 2 527 1998Didcot B 1,370 1998Little Barford 655 1995Rocksavage 750 1997Deeside (4) 250 1994Roosecote 229 1991Sutton Bridge 803 1999Medway 688 1995Killingholme 650 1994Connahs Quay 1,380 1996Killingholme (4) 450 1992Cottam Development Centre 400 1999Glanford Brigg 240 1993Keadby 720 1994Rye House 715 1993Seabank 1 812 1998Seabank 2 410 2000Shoreham 400 2000Teesside Power Station 1,875 1992Gas Fired Power Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity(MW)Bridgewater District Energy 10 2000Solutia District Energy 10 2000Sevington District Energy 10 2000Charterhouse St, London 32 1995Chickerell 45 1998Burghfield 45 1998Drax GT Gas/oil 75 1971Ferrybridge GT Gas/oil 34 1966Fiddler’s Ferry GT Gas/oil 34 1969Cowes Gas/oil 70 1982Rugeley GT Gas/oil 50 1972Grain GT Gas/oil 55 1978Kingsnorth GT Gas/oil 34 1967Ratcliffe GT Gas/oil 34 1966Taylor’s Lane GT Gas/oil 132 1979Knapton Gas/oil 40 1994St Marys Gas/oil 6 1958Lynton Gas/oil 2 1961Commission orYear GenerationBeganHydro Power Stations in the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganMaentwrog 30 1928Cwm Dyli 10 1989 (3)Dolgarrog 37 1924Kielder 5.5 1984Rheidol 50 1961Mullardoch Tunnel 2.4 1955Fasnakyle 69 1951Deanie 38 1963Culligran 24 1962Aigas 20 1962Kilmorack 20 1962Lubreoch 4 1958Cashlie 11 1959Lochay 47 1958Finlarig 30 1955Lednock 3 1961St. FillansHydro 21 1957Dalchonzie 4 1958Achanalt 3 1956Grudie Bridge 24 1950Mossford 24 1957Foyers Falls 5.2 1968Mucomir 2 1962Ceannacroc 20 1956Livishie 15 1962Glenmoriston 37 1957Quoich 22 1955Ivergarry 20 1956Cassley 10 1959Lairg Hydro 3.5 1959Shin 24 1958Sloy 160 1950Sron Mor 5 1957Clachan 40 1955Alt-na-Lairgie 6 1956Nant 15 1963Inverawe 25 1963Kilmelfort 2 1956Loch Gair 6 1961Lussa 2.4 1952Striven 8 1951Gaur 6.4 1953Cuaich 2.5 1959Loch Ericht 2.2 1962Rannoch 42 1930Tummel 34 1933Errochty 75 1955Clunie 61.2 1950Pitlochry 15 1950Chliostair 1.1 1960Kerry Falls 1.3 1951Loch Dubh 1.2 1954Nostie Bridge 1.3 1950Storr Lochs 2.4 1952Galloway (6 stations) 106 1935Lanark (2 stations) 17 1927Foyers Hydro/pumped 300 1974Pumped Storage Power Stationsin the UK(operational at the end of May 2002)Station Name Installed Year ofCapacity Commission or(MW) Year GenerationBeganDinorwig 1,728 1983Ffestiniog 360 1961Cruachan 399 196616


Figure 4-5Generation Capacity in England & Walesgas 35%interconnectors 5%coal 34%oil 4%nuclear 15% other 7%Figure 4-6Generation Capacity in Scotlandrenewables 1%hydro 19%coal 34%Gas oil 18%nuclear 27%Figure 4-7Generation Capacity in Northern Ireland4.2 The Structure of the ElectricityIndustry in the United KingdomThe electricity industry in the United Kingdomhas undergone a radical restructuring since1990 with aim of creating throughliberalisation a highly competitive marketwhere suppliers can sell nation-wide thecustomer can also choose their supplier.Privatisation was carried out in stages,beginning in England and Wales and then inScotland and finally in Northern Ireland.This has resulted in different structural,commercial and legislative arrangements forthe three regions.4.2.1 England and WalesIn England and Wales the monopolyelements of the business, that is thetransmission and distribution have beenseparated from those, which are subject tocompetition, that is supply and generation.At present the generation market in Englandand Wales is very diverse with manygenerating companies, including merchantcompanies often owing one plant. There areat least 36 companies now regarded asmajor power producers. The following chartshows the generation capacity in Englandand Wales.4.2.2 ScotlandThe Scottish electricity industry had anintegrated structure prior to privatisation,and this continued on afterwards with twocompanies, Scottish Power and Scottish andSouthern Energy. These two companiescover the full range of electricity provisionfrom generation through to supply. Each ofthe two companies has access to eachothers generation, while a third company,British Energy is a nuclear generator and iscontracted to supply its full output to theother two companies.4.2.3 Northern IrelandThe industry in Northern Ireland differs fromthe rest of the UK in a number of importantways, in that there are a small number ofcustomers in a relatively small area and untilthe mid-1990’s had been isolated from theother networks.There are only four major power stations,with two of them, Ballylumpford and Kilrootsupplying more than 90% of the electricitygenerated in Northern Ireland.4.3 Electricity Consumptionin the UKConsumption by end users accounts formost of the total demand for electricity inthe UK. In 2000, end users’ consumptionrepresented 85% of the total demand, whileconsumption by the energy industries was7.5% of the total. The remaining 7.5% werelosses from the transmission and distributionsystem and losses due to theft or meterfraud. The electricity industry itself consumesmore than half of the total electricityused by the energy industries, with oilrefineries the next most significant consumer.Figure 4-8Electricity Consumption by SectorThe first two companies schedule generationin their own areas from the plant available tothem, while British Energy provide the bulk ofthe base load in Scotland accounting forsome 50% of the output. Through a1,600MW interconnector the Scottishelectricity system is connected to therenewables 1%gas 45%coal 25%oil 18%gas oil 11%national grid in England and Wales permittingselling or buying of power from each area.agriculture 1%domestic 28%industry 28%commercial 18%losses 8%fuel industries 8%publicadministration 6%transport 3%17


Billion Metric Tons Carbon EquivalentIndustry accounted for 34.5% of the totalend users consumption in 2000, thedomestic sector for 34%, transport andother services sector for 30.5% andagriculture for the remaining 1%. Most ofthe electricity consumed by final users isdelivered through the public distributionsystem. In 2000 only 6% of electricityconsumption did not pass through the publicdistribution system, as it wasself-generated. 4.6Figure 4-9Electricity Consumption,1970 through to 2000Charting how demand has varied over the past thirty years.12108Energy industries6420DomesticIndustryServices1970 1980 1990 20004.4 UK CO 2 EmissionsEnvironmental conditions in the UnitedKingdom have improved in recent years 4.7 .While some pollutants, such as nitrogenoxides, have not decreased substantially,sulphur dioxide emissions have. As a majorcomponent of acid rain, this reduction insulphur dioxide has produced noticeableenvironmental benefits. Furthermore,the United Kingdom finds itself inthe company of only three other WesternEuropean countries-Finland, Germany andLuxembourg-in experiencing a decline incarbon dioxide emissions since 1990.The United Kingdom is an Annex I countryunder the United Nations FrameworkConvention on Climate Change. (Annex Icountries include the countries of theOrganisation of EconomicCo-operation and Development,as well as the countries designatedas Economies in Transition).The European Union, as a whole,agreed to an 8% reduction below1990 levels of a “basket” ofgreenhouse gases by the 2008-2012commitment period.Among countries of the EuropeanUnion, the United Kingdom agreedto a more challenging target of12.5% below 1990 levels.The government went even furtherand suggested a domestic goal of20% below 1990 levels by 2010.Reductions of carbon emissions in theUnited Kingdom, as well as reductions inother pollutants, such as sulphur dioxide,have resulted primarily from deregulation ofthe country’s electricity industry. Privatisationled to a reduction in coal subsidies, thusnarrowing the price differential between coaland natural gas. As a result, consumers areswitching to natural gas, and the benefits ofburning this “cleaner” fuel are being realised.In 1999, the United Kingdom accountedfor 2.6% of total world energy consumptionand was responsible for 2.5% of total worldcarbon emissions. Under the Kyoto Protocol,the United Kingdom has set a target ofreducing greenhouse gas emissions by12.5% on 1990 levels by 2008-2012,and to cut carbon emissions 20% by 2010.Energy related carbon emissions in theUnited Kingdom have fallen from 167.4million metric tons of carbon in 1990 to152.4 million metric tons in 1999, a 9%reduction. The decline in carbon emissionshas been due to a decrease in the share ofcoal (the most carbon intensive fossil fuel)in the total fuel mix. Coal has been replacedby less carbon intensive energy sourcessuch as natural gas, nuclear and renewableenergy. Likewise there has been a steadydecline in energy intensity over the pasttwenty years (see chapter 3 for details).18


5The use of Coal toGenerate Electricity5.1 What is Coal?Coal is the altered remains of prehistoricvegetation that originally accumulated asplant material in swamps and peat bogs 5.1 .The accumulation of silt and othersediments, together with movements in theearth’s crust (tectonic movements) buriedthese swamps and peat bogs, often to greatdepth. With burial, the plant material wassubjected to elevated temperatures andpressures, which caused physical andchemical changes in the vegetation,transforming it into coal.Initially the peat, the precursor of coal, wasconverted into lignite or brown coal – coaltypeswith low organic ‘maturity’. Over manymore millions of years, the continuing effectsof temperature and pressure producedadditional changes in the lignite,progressively increasing its maturity andtransforming it into the range known assub-bituminous coals. As this processcontinued, further chemical and physicalchanges occurred until these coals becameharder and more mature, at which point theyare classified as bituminous or hard coals.Under the right conditions, the progressiveincrease in the organic maturity continued,ultimately to form anthracite.The degree of ‘metamorphism’ orcoalification undergone by a coal, as itmatures from peat to anthracite, has animportant bearing on its physical andchemical properties, and is referred to as the‘rank’ of the coal. Low rank coals, such aslignite and sub-bituminous coals, are typicallysofter, friable materials with a dull, earthyappearance; they are characterised by highmoisture levels and a low carbon content,and hence a low energy content. Higher rankcoals are typically harder and stronger andoften have a black vitreous lustre. A rise inthe carbon and energy contents and adecrease in the moisture content of the coalaccompany increasing rank. Anthracite isat the top of the rank scale and has acorrespondingly higher carbon and energycontent and a lower level of moisture.Bituminous coal can be metallurgical(also known as coking coal) and usedpredominantly in the steel making process,or thermal (also known as steam coal)a term used to distinguish coals consideredparticularly suitable for boiler steamgeneration.Large coal deposits only started to beformed after the evolution of land plants inthe Devonian period, some 400 million yearsago. Significant accumulations of coaloccurred during the Carboniferous period(350-280 million years ago) in the NorthernHemisphere, the Carboniferous/Permianperiod (350-225 million years ago) in theSouthern Hemisphere and, more recently,the late Cretaceous period to early Tertiaryera (approximately 100-15 million years ago).It is found in areas as diverse as the USA,South America, Indonesia and New Zealand.Coal is currently produced in over 50countries world wide, with approximatelytwo-thirds of hard coal production beingextracted by underground mining and onethird by surface mining. Preparationtechniques are then used to reduce the ash,mineral, and sulphur and moisture contentsof many coals. Approximately 12% of allcoals produced world wide are tradedinternationally. Some 37% of the world’selectricity is coal fired, with approximately70% of global steel production dependanton coal.The following is a typical coal analysis takenfrom the EM database 5.2 , which has beensubsequently used in the coal mass balance,to cross check, in particular, the amount ofcarbon released into the environment in theform of carbon dioxide emissions, versusthat obtained by other methods (see later).The Environmental Manual for PowerDevelopment, which includes the EMdatabase, was developed for and ismaintained by the German government.The EM database for coal technologiesdistinguishes between hard coals, andlignite. Hard coals represent anthracite and19


ituminous coals, while lignites coversub-bituminous and brown coals.The EM contains pre-defined fuels for severalcountries, which deliver hard coals to theworld market. The ultimate analyses of thesetypical fuels are taken directly from files ofthe German Association of Coal Importers(VdKoI 1992). Based on this data, a generichard coal composition was estimated for theEM (see following Table 5-1). The equivalentlignite generic coal composition is not givenas the UK burns only hard coal 5.3 .Table 5-1 The EM Database: CoalComponent Unit Australia Poland South Africa USA EM genericCarbon wt% 67.0 67.0 65.0 73.0 67.0Hydrogen wt% 3.0 3.9 3.0 3.0 3.0Sulphur wt% 0.5 1.0 0.7 1.0 1.0Oxygen wt% 7.5 10.1 7.5 7.5 8.0Nitrogen wt% 1.4 1.5 1.4 1.4 1.0Chlorine wt% 0.1 0.1 0.1 0.1 0.1Fluorine wt% 0.01 0.01 0.01 0.01 0.01Water wt% 8.0 7.0 9.0 6.5 7.9Ash wt% 12.5 9.4 13.3 7.5 12.0HHV MJ/kg 26.1 27.0 26.0 28.3 26.0Figure 5-1The Uses of Coal 5.45.2 The Use of Coal forGenerating ElectricityCoal is currently the single largest fuelsource for the generation of electricity worldwide with currently approximately 38% ofthe world’s electricity being generatedusing coal 5.4 .However coal was the only primary energysource to experience a production declinebetween 1991 and 2000. Productiondecreased by 57 million short tons, over theperiod. China was the leading producer in2000 at 1.3 billion short tons (Bst), with theUnited States the second leading producerin 2000 with 1.1 Bst. India was ranked adistant third at 345 million short tons (Mmst),followed by Australia, at 337 Mmst, andSouth Africa at 326 Mmst. Together, thesefive countries accounted for 67 percent ofworld coal production in 2000 5.5 .However, while the production of coal fell,world coal consumption grew by 1.2% 2.2Bst, with demand in the US rising by 3.3%and Europe experiencing its first increase incoal consumption for over a decade.However, China, the worlds second largestcoal consumer, saw another sharp fall indemand, down by 6.4% 5.6 .The world reserves of coal are an estimated227 years (expressed as a multiple of annualproduction at the end-2000). Proven coalreserve total some 984 billion tonnes, ofwhich 509 are hard coal (anthracite andbituminous). The US has the largestpercentage at 25.1% of known reserves,followed by Russia (15.9%), China (11.6%),Australia (9.2%), India (7.6%),Germany (6.8%) and South Africa (5.6%). 3In terms of supply and demand, Europe isthe only trading block whose demand forcoal significantly exceeds its ability to supply.America, the former Soviet Union and Africaall supply more than they consume, while theAsian Pacific region has a marginal demandfor coal supply.Coal production and consumption in theUnited Kingdom have decreased dramaticallysince 1986. UK coal production fell from 119Mmst in 1986 to 40.9 Mmst in 1999.Production fell again in 2000, but demandrose, increasing imports. In 2000, steam coalaccounted for 80% of coal demand, cokingcoal for 15% and anthracite for 5%.Electricity demand accounted for 95% ofdemand for steam coal and 46.5% ofdemand for anthracite 5.7 . Approximately 47million tonnes of coal were used in 2000 toproduce some 119960 GWh of electricity,which is equivalent to 396g per kWh ofelectricity. The average efficiency of a coalfired power station in the OECD countrieshas been taken as 35% 5.8 .20


In the late 1980s, coal accounted for abouttwo-thirds of the United Kingdom’s thermalelectricity production. Currently, less thanhalf of UK thermal electricity is coal-fired(around 34% in 2000), and the figure isexpected to fall below one-third by the endof the decade.However more recently, government figureshave shown that in the first quarter of 2001coal consumption rose 17.4 percent against3.6 percent for gas. In 2000 the amount ofcoal burned in power stations rose 15percent compared with 1999 levels.In contrast gas use rose only 0.7 percentover the same period. But the “dash for gas”- a defining characteristic of the lastdecade’s electricity generation trends whichsaw gas-use shoot up - has stalled in theface of soaring wholesale gas prices.Therefore, analysts say the reason is simple -coal is cheaper than gas. Burning coal toproduce electricity currently works out atabout 12 pounds a megawatt hour againstabout 12.5 pounds when burning gas. Coalplant is also a lot more flexible than gas-firedgeneration, an attribute that has becomemore prized following the introduction inMarch of a new wholesale trading market(NETA) which rewards predicable output 5.9 .Coal mines are located primarily in centraland northern England and southern Wales,with some coal mines also found in southernScotland. The UK produced 40.5 million tonsof bituminous coal and 409 thousand tons ofanthracite coal in 1999. The UK alsoproduces coke-oven coke in quantitiessuch that it is self-sufficient. Nevertheless,net imports of coal in 1999 were 23.9 milliontons, and this figure is expected to increase.Between 1984 and 1985, the British coalminers’ union staged a yearlong strike.The strike dramatically altered energyproduction and consumption patterns inthe United Kingdom for that year andprecipitated the longer-term decline ofthe industry.5.3 Generating Electricity Using CoalFigure 5-2 Schematic of a Coal-Fired Power Station 5.10Flue gases used topre-heat air/coal dustPower stationAshFurnaceCoal-fired stations produce steam to driveelectricity generators. Several of the largestcan generate about two gigawatts, and Drax(in Yorkshire) can supply nearly twice that,which is enough for a large city.The coal is typically shipped to a powerplant by rail car or barge. In addition tothe carbon content, coal contains ash(alumino-silicates) and trace metals.CoolingtowerMillCoal isground intofine powderhereWarmedcooling wateris cooledby airCondenserHotsteamcoolshereFlue gases exit throughchimney stackTurbinesGeneratorWarmed coolingwater returns tocooling towerCold coolingwater used tocondense hotsteamCoolingairA single coal-fired boiler in a modern powerstation can burn over 260 tonnes of coal anhour. The coal is used to boil water andproduce steam. Because the steam iscontained in a closed system of pipes,it reaches a very high pressure, and can bedirected through the vanes of a turbine tokeep them spinning. The spinning shaft ofthe turbine drives an electricity generator.Once it has passed through the turbine,the hot steam is cooled in a condenser andreturned to the boiler to repeat its cycle.21


In practice, the process is a little morecomplicated than this. To increase the rateat which the coal burns; it is ground to a veryfine powder and mixed with pre-heated airbefore being blown into the furnace, where itburns like a gas. The steam emerging fromthe boiler is passed in pipes through thefurnace to be ‘superheated’, which greatlyincreases its pressure and therefore theenergy it can transfer to the turbine.This superheated steam may reachtemperatures as high as 560°C - enoughto make the pipes glow red. The hot fluegases emitted by the burning coal areused to pre-heat both the air needed forcombustion and the condensed waterreturning to the boiler.The condenser dissipates its heat throughdirect cooling by river or seawater, or byevaporating water in a cooling tower. Variouschemicals are used to treat the cooling waterto minimise corrosion, fouling and scaling.This treatment process can result in certainwaste waters and waste solids. Releases towater may include chemicals from the watertreatment, as well as from the coal itself,where chemicals can be ‘leached’ from thecoal, if the coal is allowed to become wet.In addition to the burnable carbon, the coalcontains ash, which is removed from thebottom of the furnace (called appropriately‘bottom ash’). There is also dust in the fluegases emerging from the boiler and ifuntreated, these can cause large pollutionproblems. This dust is filtered out in allindustrial countries before the gases arereleased, but many power stations in lessdeveloped countries emit this dust to the air.Coal also contains many heavy metals,which are mostly bound in the ash and thedust. Ash from the burning process istypically sent to an ash pond, landfills or isused commercially. Other waste solids mayalso be sent to the land.In addition to fly ash, the flue gases containother contaminants, including carbondioxide, sulphur dioxide, and nitrogen oxides.In general the carbon dioxide emissions arenot directly measured because they arerelatively easy to calculate using a model ofcombustion based on fuel carbon content,calorific value and fuel efficiency. That is theapproach taken in this report, where it wasalso assumed that in most of the relevantprocesses combustion efficiency exceeds99% and therefore the emission factor islargely a function of the fuel used 5.11 .There is also dust in the flue gases emergingfrom the boiler and if untreated, these cancause large pollution problems. This dust isfiltered out in all industrial countries beforethe gases are released, but many powerstations in less developed countries emit thisdust to the air.Coal also contains many heavy metals,which are mostly bound in the ash and thedust. Ash from the burning process istypically sent to an ash pond, landfills or isused commercially. Other waste solids mayalso be sent to the land.In addition to fly ash, the flue gases containother contaminants, including carbondioxide, sulphur dioxide, and nitrogen oxides.In general the carbon dioxide emissions arenot directly measured because they arerelatively easy to calculate using a model ofcombustion based on fuel carbon content,calorific value and fuel efficiency. That is theapproach taken in this report, where it wasalso assumed that in most of the relevantprocesses combustion efficiency exceeds99% and therefore the emission factor islargely a function of the fuel used 5.11 .Emissions of sulphur dioxide depend againcritically on the sulphur content of the fueland any ‘clean up’ technology used.The sulphur content of indigenousbituminous coals used in the UK for powergeneration is in the range 0.5% to 4.0% 5.12 .A typical analysis for coals extracted in theUK is 1.6%5.13. Due to the increasing usageof imported coal for steam generation, thisfigure will decrease, as the average sulphurcontent in imported coal is lower.Nitrogen oxides (NOx) are formed by theoxidation of a portion of the nitrogencomponent of the fuel and by the reaction ofatmospheric nitrogen and oxygen at hightemperatures. Models have been NOxformation have been derived, and show thatthe most important factors are the flametemperature and the oxygen concentration inthe flame. This knowledge has been used inthe design of combustion techniques toabate NOx formation.In terms of the nitrous oxide emissions,which are the least well know of all the directgreenhouse gases, .the only significantemissions concerned with the life cycleanalysis of the coal combustion industry arethose associated with the combustionprocess itself. This is the subject of somecontroversy in the literature and will becovered in more depth in chapter 10 of thisreport. In this report the thermal efficiency ofa conventional coal powered station hasbeen assumed to be 35% 5.14 which is in linewith other energy balances. Official UKfigures for 2000 5.15 give the thermal efficiencyof conventional thermal stations as 36%,up from 33.9% in 1990. However, these dovary from year to year, and also depend onwhether the power station concerned uses aflue gas desulphurisation (FGD) system forthe removal of sulphur dioxide from the gasstream, or NOx abatement techniques. If itdoes the abatement technologies impact onthe thermal energy efficiency (reducing it byup to 2% 5.16 ) and increases the carbondioxide emissions, in the case ofdesulphurisation. Firstly, the decrease inthermal efficiency automatically increases thecarbon dioxide emitted per kWh of electricitygenerated, and secondly, for each sulphurdioxide molecule removed, one carbondioxide molecule is emitted, increasing onaverage the carbon dioxide emitted by7g/kWh 5.17 . While FGD systems and lowNOx burners are required for all new powerstations, and have been retrofitted to someolder units, this report has assumed thatthese systems are not used, due todifficulties in calculating the contributionto the thermal efficiency and carbondioxide emissions.Table 5-2 Statistics for coal-firedpower stations in the UK, 2000Number of power stations 16 with 4 mixed fuelOutput range 393 – 3870 MW installed capacityEfficiency range (efficiency of converting chemicalenergy in coal to electrical energy) 21%-39%(average 31%)Output from typical 800MW station at35% efficiency using coal of calorific value27.9MJ/kg:per kWh per day(tonnes)Coal consumed 396 grams 7673SO2 produced 12 grams 233SO2 produced 1.2 grams 23(with FGD)Nox produced 4 grams 78NOx produced 2.6 grams 50(with LNBs)CO2 produced 970 grams 18,794CO2 produced 979 grams 18,968(with FGD)Ash produced 48 grams 930Gypsum produced 32 grams 62022


6The use of Oil toGenerate Electricity6.1 What is Oil?Together with natural gas oil makes uppetroleum, which is Latin for ‘rock oil’, andwas known as bitumen in ancient times.Most geologists today agree that crude oilforms over millions of years from the remainsof tiny aquatic plants and animals that areexposed to the combined effects of time andtemperature. In other words, oil forms fromorganic matter that is either ‘cooked’ deepwithin the earth for long periods of time atlow temperatures, or ‘cooked’ for shortperiods of time at high temperatures 6.1 .Fossil organic matter is called kerogen andsulphur rich kerogens form oil sooner, and atlower temperatures, than other types oforganic matter. This is because the atomicbonds between carbon and sulphur breakmuch faster than carbon-oxygen bonds.Then a period of time in anaerobic, that isoxygen-deficient mud, was required afterthe animals had died when the organicmaterial was converted into kerogen.Finally if sufficient kerogen remained, it waslater converted into oil. In summary mostcrude oil formed from microscopic plantsand animals that died millions of years agoand were rapidly buried under conditions,which favoured their preservation.Given deeper burial with sufficient time andtemperature, the soft parts of theseorganisms, over probably millions of yearswere slowly converted to oil.Condensate density tends to be lower thanwater, so it floats easily, where in contrastsome of the heavy oils can sink rather thanfloat. Most oils are mixtures of manydifferent compounds, most of which arehydrocarbons. Saturates are hydrocarbonsconsisting of straight chains of carbon atoms,while aromatics are hydrocarbons consistingof rings of carbon. Asphlatenes are complexpolycyclic hydrocarbons that contain manycomplication carbon rings. In addition tohydrogen, carbon and oxygen being present,it is also common to find sulphur.Table 6-1Typical North Sea Heavy FuelOil Composition 6.3Average Crude Oil Percentage (%)CompositionCarbon 86.3Hydrogen 11Sulphur 1.5-3.5Nitrogen 0.2-0.3Ash 0.04-0.1Moisture 0.1-1GCV 41.6-42.7NCV 39.3-40.3Petroleum is therefore essentially a mixtureof naturally occurring organic compoundsfrom within the earth, consisting primarilyof hydrogen, carbon and oxygen.When petroleum comes straight out ofthe ground as a liquid it is called crude oil;if dark and viscous, and condensate ifclear and volatile. When solid, it is asphalt,and when semi-solid, tar. There is alsonatural gas which van be associated with oilor found alone 6.2 .Crude oil comes in many forms, and indeedcolours, usually being black, but green,red and brown oils are not uncommon.23


Table 6.1 is a typical North Sea oil analysisfrom the ExternE project, which was takenas the typical gas analysis for this reportsmass balance. The location for the oilextraction was taken to be the Alba field,UKCS, in the North Sea.6.2 The Use of Oil forGenerating ElectricityPetroleum oil is a vitally important elementof the world’s economy. It provides fuel fortransport, heating and power generation,and is used to make a huge range ofpetrochemicals from plastics to paints. It isestimated that oil accounts for 8.5% of theworld’s electricity generation (1999) 6.4 .The use of oil in power generation hasdeclined in recent years because of risingprices and direct competition from naturalgas. As well as being cheaper, gascombustion is much cleaner, making iteasier for the generating companies to meetincreasingly stringent pollution limits.Many people would argue that it makesmore sense to reserve a valuable resourcelike oil for transport and petrochemicalsrather than burning it to generate power.However, as always, there are many factorsto consider - economic, environmental,social and political.As oil-fired burners are relatively easy toquickly start up and shut down, they areincreasingly used to meet the variable peaksin demand which are encountered very dayin a typical electricity network, therebymaximising oil’s potential for flexibility, whilstminimising the cost associated with the fuel.Global consumption of petroleum (whichincludes both crude oil and natural gas plantliquids) increased by 9.3 million barrels perday between 1991 and 2000, an averageannual rate of growth of 1.5 percent.Saudi Arabia, the United States andRussia were the three largest producers ofpetroleum in 2000. Together they accountedfor 31.7% of the world’s petroleum 6.5 .In 2000 the world consumption of oil roseby 1%, effectively in line with it 1990-2000average. However, this total disguisedmarked regional variations. The growth inconsumption 6.6 in almost every region wasbelow its 10 year average, but this was offsetby a relative improvement in the countriesthat comprise the former Soviet Union (FSU).Oil consumption also fell there, but bysignificantly less than the average rate ofdecline for 1990-2000.In the year 2000 proven oil reserves were anestimated 40 years 6.4 , expressed as amultiple of annual production. The followingtable gives the worlds crude oil reserves asof January 1st 2002. (Table 6.2)North Sea oil and gas reserves were firstdiscovered in the 1960’s, but did notimmediately emerge as a key non-OPEC oilproducing area until later. Although theregion is a relatively high cost producer, itshigh quality crude oil, political stability andproximity to major European consumermarkets have allowed it to play a major rolein the world oil and gas markets. Many of theworlds major crude oil prices are linked tothe price of the North Seas Brent crude oil,which is a mixture of North Sea crude oils.The North Sea is considered a ‘mature’ areawith few large discoveries likely to be made.Only a few frontier areas hold the possibilityof further discoveries of large oil and gasfields. The UK holds about 5 billion barrels ofproven oil reserves, mostly in the North Sea.There are over 100 oil and gas fieldscurrently on stream, and several hundredcompanies are active in the area.The production has been declining since1999, with 2.75 million barrels per daybeing produced in 2000. Most of the highquality crude oil is exported, while cheaper,lower quality crude oils are imported forrefining, mostly from the Middle East.Table 6-2World Crude Oil Reserves 6.7Crude Oil(Billion Barrels)Region Oil and Gas WorldCountry Journal OilNorth AmericaCanada 4.9 5.4Mexico 26.9 23.1United States 22.4 22.4Total 54.2 50.9Central& South AmericaArgentina 3.0 2.9Brazil 8.5 8.6Venezuela 77.7 50.2Total 96.0 69.1Western EuropeNorway 9.4 10.3United Kingdom 4.9 4.6Yugoslavia 0.1 NATotal 17.3 17.7Eastern Europe& Former USSRKazakhstan 5.4 NARussia 48.6 53.9Total 58.4 67.1Middle EastIran 89.7 99.1Iraq 112.5 115.0Kuwait 96.5 98.8Oman 5.5 5.9Qatar 15.2 13.8Saudi Arabia 261.8 261.7United Arab Emirates 97.8 62.8Other 0 0.7Total 685.6 662.5AfricaAlgeria 9.2 17.0Angola 5.4 6.0Libya 29.5 30.0Nigeria 24.0 30.0Total 76.7 94.9Asia & OceaniaChina 24.0 29.5India 4.8 3.8Indonesia 5.0 9.2Malaysia 3.0 4.5Total 43.8 56.5World Total 1,032.0 1,018.724


Figure 6-1Schematic of an Oil Fired Power Station 6.9Flue gases exit throughchimney stackFlue gasesused topre-heat oilPower stationOil injectedas dropletsFurnaceHot SteamTurbinesGeneratorCondenserWarmed coolingwater returns tocooling towerCold cooling waterused to condensehot steamAshHot steamcools here25


At present average production costs are$15 per barrel 6.8 .The UK’s crude oil refining capacity isapproximately 1.77 million barrels of oil perday, just slightly above the countryconsumption of 1.7 million barrels per day,for which demand varies seasonally.Petroleum products represented 45% offinal energy consumption in 2000, with thetransport sector consuming 74% of thepetroleum products in the same year.Nationally, the energy sector consumed just7%, 1.55 below the world average of 8.5%.This was equivalent to 1.34 million tonnesof oil.6.3 Generating Electricity Using OilEven a relatively small 500-megawatt powerstation may burn nearly 3,000 tonnes ofheavy fuel oil in a single day. They aretherefore normally situated either close toan oil refinery so that oil can be pipeddirectly, or on the coast or an estuary fordeliveries by sea. They also need largestorage tanks on site to ensure a constantsupply.Oil is sprayed into the boiler furnace as acloud of fine droplets, along with a supplyof air, to help the oil burn as completely aspossible. Water passing through the boilerin tubes turns to steam, which reaches veryhigh pressures because it is contained in aclosed system. The steam is directedthrough the vanes of a turbine to keepthem spinning, and the spinning shaft of theturbine drives an electricity generator.Once it has passed through the turbine,the hot steam is cooled in a condenser andreturned to the boiler to repeat its cycle.In practice, a number of refinements improveoverall efficiency with which the fuel’schemical energy is converted into electricalenergy. The steam tubes from the boiler arerouted back through the hottest part of thefurnace to superheat the steam and increaseits energy before it enters the turbine.The hot flue gases, on their way to thechimney, are used to pre-heat thecombustion air before it enters the furnace,and also to pre-heat the water before itenters the boiler. Flue gases are drawn outof the furnace to the chimney by a fan,to ensure they do not linger to inhibitcombustion.Large oil-fired power stations were built inthe UK from the late 1960s to the early1980s. The discovery of North Sea oil from1970 onwards was an incentive to installoil-burning plant as an alternative to coal.However, rising prices worldwide reducedoil’s competitiveness. New fossil-fuel stationsbeing built in the UK use natural gas, whichis also easier to burn cleanly to meetincreasingly stringent limits on pollution.Power stations using oil, sometimes withcoal or gas-fired boilers on the same site,currently make up about 2% of the UK’s totalelectricity generating capacity, down from14% in 1994. There were also many smalloil-fired boilers supplying private users suchas factories, but these too tended to bereplaced by gas-fired plants.In terms of emissions, the same commentshold for oil as those found in Chapter 5.3for coal, and Chapter 10 on emissions.However, the main difference between coaland gas, is that the amount of solid residueproduced by burning oil is insignificant whencompared to that produced burning coal,albeit that oil is more polluting in terms ofgaseous emissions than natural gas.In conclusion, oil is easy to transport directlythrough pipes without using road vehicles.It provides flexible power generation ondemand, and can meet pollution limits withmodern techniques. However, it burns lesscleanly and efficiently than natural gas.Also, it is a limited resource, which providesour transport fuels and a huge range ofpetrochemical products.Table 6-3 Statistics for oil-firedpower stations in the UK, 2000per kWh per day(tonnes)Oil consumed 396 grams 7673SO2 produced 13.9 grams 269SO2 produced 1.4 grams 27(with FGD)NOx produced 3.72 grams 72NOx produced 2.42 grams 47(with LNBs)CO2 produced 755 grams 14,628CO2 produced 766 grams 14,841(with FGD)Output from typical 800MW station at35% efficiency using fuel oil of calorific value42.3MJ/kg26


7The use of Gas toGenerate Electricity7.1 What is Gas?Natural gas is in many ways the ideal fossilfuel. It is clean, easy to transport andconvenient to use. Currently about half thegas produced is used in industry, while alarge portion is also utilised in the home forheating, lighting and cooking. However, likewith everything there are limits on how muchgas is available and obtainable using today’stechnologies.Research is continuing on how natural gaswas formed, and where it has collectedwithin the earth’s crust. It has been foundthat gas is not only found in pockets by itself,but in many cases it is found alongside oil,and both flow together to the surface fromthe same underground formation.Like oil production, some natural gas flowsfreely to the surface, due to the naturalpressure of the underground reservoir beinghigh enough to force the gas through thereservoir rocks. Only a small number ofthese free-flowing gas formations still exist.Almost always some type of pumpingsystem will be required to extract the gaspresent in the underground formation.Often the flow of gas through as reservoircan be improved by creating tiny cracks inthe rock called ‘fractures’. These serve asopen pathways for the gas to flow. In atechnique known as ‘hydraulic fracturing’drillers force high pressure fluids like waterinto the formation to crack the rock.A ‘propping agent’ like sand or tiny glassbeads, is added to the fluid to prop open thefractures when the pressure is decreased.Natural gas can be found in a numberof different underground formations,including 7.1 :1. Shale formations2. Sandstone bedsSome of these formations are more difficultand expensive to produce than others, butultimately all are accessible.Other more speculative sources of methaneexist, which include:1. Light sand lenses where the gas is heldin sandstone deposits where the holesare very small, and therefore it is verydifficult for the gas to flow throughthese structures.2. Coal bed methane gas which is found inall coal deposits was once viewed solelyas a safety hazard, but now due toongoing research is regarded as apotential gas source.3. Another gas deposit is that found indeep ocean beds or in cold areas,called methane hydrate. A methanehydrate is a tiny cage of ice inside ofwhich are trapped molecules ofnatural gas.Once natural gas is produced from theunderground rock formation, it is sent bypipeline to storage facilities and fromthere on to combustion plants, homesand factories by smaller pipes, through awell organised distribution system.Table 7-1Typical North Sea Heavy FuelOil Composition 7.2Composition Value (%)of GasMethane 93Ethane 3Heavier Alkanes 1Nitrogen 3Carbon Dioxide 0.3Hydrogen Sulphide Not quotedHeating ValueNot quoted3. Coal seams, and4. Deep salt water aquifers(which are underground pools of water).27


7.2 The Use of Gasfor Generating ElectricityThe use of gas for power generation hasincreased rapidly in the European Unionsince the early 1990’s after the EuropeanUnion removed a ban on using it for thispurpose. The natural gas share of utility fuelswas 1% in 1988. In 1994 it had alreadyovertaken oil to account for 10% of thepower generated, however, by 2000, it hadalso overtaken the use of coal, and stood ataround 41%. Forecasts predict that it willincrease to 50% by 2010 (see reference 7.7).Worldwide, the use of gas for electricitygeneration is 17.1% 7.3 of the total worldelectricity generation.There are a number of reasons for thisrapid acceleration in the use of natural gasto generate electricity and these include:1. Gas was very attractive from aneconomic viewpoint in themiddle 1990’s.2. A new gas-fired power station can bebuilt more quickly and cheaper than theequivalent coal or oil plant.3. The government was encouraging theuse of gas, which burns comparativelycleanly to help achieve the nationaltargets for reduced total emissionsof pollutants.As was discussed in Chapter 5, on the useof coal to generate electricity, more recentlygovernment figures have shown that in thefirst quarter of 2001 coal consumption rose17.4 percent against 3.6 percent for gas.In 2000 the amount of coal burned in powerstations rose 15 percent compared with1999 levels. In contrast gas use rose only0.7 percent over the same period. But the“dash for gas” - a defining characteristic ofthe last decade’s electricity generation trendswhich saw gas-use shoot up, - has stalled inthe face of soaring wholesale gas prices.Therefore, analysts say the reason is simple -coal is cheaper than gas. Burning coal toproduce electricity currently works out atabout 12 pounds a megawatt hour againstabout 12.5 pounds when burning gas.Coal plant is also a lot more flexible thangas-fired generation, an attribute thathas become more prized following theintroduction in March of a new wholesaletrading market (NETA) which rewardspredictable output 7.4 .World wide the production of dry natural gasbetween 1991 to 2000, increased by anaverage annual rate of 1.8%, or by 13.3trillion cubic feet in 2000 alone. Russia wasthe leading producer in 2001 at 20.6 trillioncubic feet with the United States followingat 19 trillion cubic feet. Together thesecountries produced 45% of the world’s total.Canada is ranked third with 6.5 trillion cubicfeet while the United Kingdom is fourth with3.4, and Algeria fifth with 2.9 trillion cubicfeet. These last three countries account for15 percent of the world’s production 7.5 .It should be noted that the production ofnatural gas appears to be quite volatile withthe figures for 2000 for the United Kingdomplacing it in third place, followed in this caseby Canada and Germany. In 2001, Canadaeffectively doubled its production of naturalgas, due to an increase in demand fornatural gas (see below).BP, in its annual review in 2000 noted thatnatural gas was the fastest growing fuel in2000, with global consumption rising by4.8%, the highest rate since 1996. This wasdriven in particular by a 5.1% rise in demandin Canada and the US. Chinese consumptionincreased by 16% although in absolute termsChina only represents 1% of the world’snatural gas consumption. In contrast the USand Canada consumes 30%. Gas outputresponded to this increase and the highestrise in some time, more than doubling theaverage of the past decade 7.6 .Proven reserves of gas in 2000 7.6 , were anestimated 61 years, expressed as a multipleof annual production. The following tablegives the worlds natural gas reserves asof January 1st 2002 7.7 . It is interesting tocompare the natural gas distribution withthat of oil; natural gas appears to be morewidely found, albeit, not all the reservesare economically viable whether fromgeographical or market access perspectives.This is perhaps why there is so muchtechnical focus on effective liquefaction overconsiderable distances.The UK contains approximately 26 trillioncubic feet (Tcf) of natural gas reserves, mostof which are in non-associated gas fieldslocated off the English coast in the SouthernGas Basin, adjacent to the Dutch NorthSea sector 7.7 .Table 7-2World Natural Gas ReservesBatural Gas(Trillion Cubic Feet)Region Oil and Gas WorldCountry Journal OilNorth AmericaCanada 59.7 59.7Mexico 29.5 39.0United States 183.5 183.5Total 272.7 282.1Central &South AmericaArgentina 27.5 26.8Bolivia 24.0 27.4Trinidad and Tobago 23.5 19.7Venezuela 147.6 149.2Total 253 250.2Western EuropeNetherlands 62.5 57Norway 44.0 77.2United Kingdom 26.0. 24.5Total 160.7 182.4Eastern Europe& Former USSRKazakhstan 65.0 NARussia. 1,680.00 1,700.00Turkmenistan 101.0 NAUkraine 39.6 NAUzbekistan 66.2 NATotal 1,967.90 1,950.50Middle EastIran 812.3 939.4Iraq 109.8 112.6Kuwait 52.7 56.6Oman 29.3 30.5Qatar 508.5 757.7Saudi Arabia 219.5 228.2United Arab Emirates 212.1 204.1Total 1,974.60 2,367.90AfricaAlgeria 159.7 175.0Egypt 35.2 54.1Libya 46.4 46.9Nigeria 124.0 159.0Total 394.8 477.1Asia & OceaniaAustralia 90.0 80.0China 48.3 42.8India 22.9 15.4Indonesia 92.5 87.5Malaysia 75.0 82.5Pakistan 25.1 24.1Total 433.3 419.9World Total 5,457.10 5,930.2028


Figure 7-1The Structure of a Gas Fired Power Station 7.9First StageSecond StageWaste heat boilerWater in here is heated andturned into steamgas injectedinto combustionchamberSteam injectedinto turbineTurbinebladesGeneratorCondensersGeneratorAircompressorbladesTurbinebladesHotexhaustgasesSteamcondensedback towaterThe Irish Sea has the large Morecambe andHamilton fields, with Morecambe aloneaccounting for up to 20% of the Britishnatural gas production. The last project tocome on-line in 2001 is the TotalFinaElfoperated Elgin/Franklin platform, whichmay be the last big North Sea productionplatform. It is also the world’s largest highpressure, high temperature development,and has, unlike the others, extensiveprocessing facilities. Most of the other gasis processed on-shore.British Gas was the monopoly supplier to theinterruptible market until the passage of the1995 Gas Act. The consumer gas marketwas deregulated by 1998 with the effect thatall residential and commercial customerscould choose their own supplier. By the endof 2000 suppliers other than British GasTrading had captured between 20 to 30% ofthe market in many regions of the UK.The UK’s gas and regulatory body is theOffice of Gas and Electricity Markets(OFGEM). OFGEM has proposed reformingprice controls on pipeline usage fees.The privatisation of the UK’s gas industryleading to an increased gas supply andreduced prices, has, as indicated above,helped gas to replace much of the UK’sreliance on coal as a source for electricitygeneration. It should also be noted thatprivatisation in the UK has progressed well inadvance of EU requirements.The first natural gas pipeline to link theUK to the European continent was openedin 1998, is known as the UK-ContinentInterconnector and has terminals at Bacton,England and Zeebrugge, Belgium.There is at present one pipeline linkingIreland to Britain to access the Scottishgas sources, however there are morebeing planned after permission wasgranted in 2000. Despite these projectsthe UK remains a much smaller naturalgas exporter than Norway, and hasbecome a net importer again as the newNorwegian field, Vesterled, came on line.However, the return to importing naturalgas, has tended to increase the gas price,and raise it’s volatility, due to the UK’ssystem of auctioning entry capacity oraccess rights to the national pipeline.7.3 Generating Electricity Using GasConventional gas-fired power stationsuse an open-cycle gas turbine (OCGT).Natural gas is burned in a combustionchamber where it heats a continuous supplyof compressed air. The air and burned gasexpand and escape under high pressurethrough the multiple blades of a turbine,causing it to spin. The spinning turbineshaft drives an electricity generator andalso the air compressor, which feeds thecombustion chamber.In an OCGT power station, the hot exhaustgases are vented to the atmosphere, andmost of the heat energy they contain iswasted. Today, power stations being builtinclude a second stage which uses this heatto generate more electricity.Instead of being vented, the exhaust gasesfrom the first turbine pass through a boiler,heating water to produce steam which drivesa second turbine and electricity generator.The steam is then condensed back to waterin an air-cooled condenser before passingback into the boiler in a continuous cycle.This type of plant is called a combinedcycle gas turbine (CCGT). It can convertmore than 50% of the chemical energy inthe gas to electrical energy - a very efficientprocess compared with any other kind offossil-fuel power station. The overallefficiency can be improved to 80% or morein a combined heat and power plant(see Chapter 12 for more details).Combustion turbines were first developedin the late 18th century but were noteconomically practical until the 1930’s.The first sizeable gas turbine power plantbuilt expressly for power generation wascompleted in 1939 by Brown Boveri.This plant was used for standby power only.29


Although gas turbines were first used instationary applications, much of theirdevelopment has occurred in the effort todevelop better aircraft propulsion systems.During the 1960’s gas turbines first beganto appear in quantity in the power generationmarket. The first applications were to providepeaking power, taking advantage of theturbine’s ability to start-up quickly.General Electric (GE) and Westinghouseboth formed power generation designgroups that were independent of theiraircraft engine groups 7.8 .Between 1960 and 1970 gas turbineefficiency was increased through higherpressure ratios and higher turbine inlettemperatures achieved through turbinecooling. GE began development of awater-cooled turbine in the early 1960’s,but the first model was not testedsuccessfully until 1973. By the early 1960’sboth GE and Westinghouse were offeringgas turbine power systems sold as standardpackages which allowed for multiple saleswith little redesign and lowered system cost.In 1963, GE installed the first large (250MW)combined-cycle power plant at HorseshoeLake Station in Oklahoma, United States.This combined cycle plant consists of a gasturbine the exhaust of which comprises thecombustion air for a steam generator whichsupplies steam to a steam turbine cycle.However, until the early to mid-1970’s,GE, Westinghouse and Brown Boveri weremostly selling “recuperative” combined-cycleplants which consisted of a gas turbineexhausting to a heat recovery steamgenerator (HRSG) which supplied steam to asteam turbine cycle with no supplementaryheating of the exhaust. The recuperativeplants of the time achieved thermal efficiencyof approximately 41 percent.However, it is true to say that the success ofgas turbine power systems has resulted fromthe successful inter-reaction between military/ technology R&D and a variety of regulatoryand market factors worldwide, which hasresulted in a major take up of this particularmethod of generating electricity.In 1988 the European Council adoptedthe Large Combustion Plants Directive(LCPD) to reduce emissions of pollutantsfrom power stations and other sources.This sets emissions limits for new plants andrequires progressive reductions for existinglarge plants.Figure 7-2The 24 hour Electricity Demand Cycle in the UKDemand (GW)504030201000 2 4 6 8 10 12 14 16 18 20 22 24HoursNatural gas isan importantelement in the UKGovernment’s programme to meet itsinternational commitments, since it burnsmuch more cleanly than either coal or oil.OilSmall coal stationsLarge coal stationsImportsGas (CCGT)NuclearGas contains very little material which cannotburn, so virtually no dust is emitted in theexhaust gases. Carbon dioxide (CO 2 ),a ‘greenhouse gas’ which contributes toglobal warming, is a by-product of burningfossil fuels because the carbon andhydrogen in the fuel react to produce carbondioxide and water. however, the highlyefficient CCGT power stations burn muchless fuel per unit of electricity generated thanany coal or oil-fired station, and thereforeemit less carbon dioxide - only half thatemitted by a coal-fired station. Also, naturalgas contains only trace amounts of sulphurand therefore produces very little sulphurdioxide (SO2), a main constituent of‘acid rain’.Nitrogen oxides (NOx) are the other mainconstituents of acid rain. They are producedwhen nitrogen in the fuel reacts with air usedfor combustion. Natural gas emits only abouta quarter as much NOx as coal per unit ofelectricity generated.Due to the particularly economic and cleanmethod of producing electricity with CCGT,the CCGT power stations are normally keptin constant operation to provide what isknown as the ‘base load’ demand forelectricity. The less efficient generationmethods, for example, OCGT and oil areonly used to meet short term peaksin demand.Pumped storageTable 7-3 Statistics for gas-firedpower stations in the UK, 2000per kWhper day(tonnes)Gas consumed 237 grams 4592Gas consumed 158 grams 3061(with CCGT)SO2 produced 0 grams 0SO2 produced 0 grams 0(with CCGT)NOx produced 0.695 grams 13.47NOx produced 0.463 grams 8.98(with CCGT)CO2 produced 651 grams 12,614CO2 produced 434 grams 18,409(with CCGT)Output from typical 800MW station at 46% efficiencyusing CCGT of calorific value 42.3MJ/kg:30


8The use of Nuclear Power toGenerate Electricity8.1 What is Nuclear Power?Nuclear and fossil-fuelled power stationsboth use heat to produce steam, whichdrives a turbine, coupled to a generator.The fossil fuels, namely oil, coal and gas,have been covered in the previous threechapters. In fossil-fuel fired stations,the heat is produced when coal, oil or gas isburnt, producing carbon dioxide, other gasesand solid waste. In nuclear reactors however,the heat comes from energy released whenthe nuclei of uranium or plutonium atoms aresplit, this process is known as fission.The energy recoverable from each tonne ofnuclear fuel depends on the type of reactorand fuel cycle, but is at least 10,000 timesthat released when one tonne of coal isburnt in a power station.Or put another way 8.1 , one pellet of a nuclearfuel called MOX (mixed oxide) weighing just 6grams can yield the same amount of energyas a tonne of coal. Three pellets can providea family with electricity for one year. All thisand zero emissions of carbon dioxide.All nuclear power stations use uranium asfuel; in Britain some power stations (usingMagnox reactors) have uranium metal astheir feed stock. Others, including theAdvanced Gas Reactors (AGR’s) in the UKused uranium dioxide as their principal fuelsource, albeit now enriched with plutonium inthe MOX fuel pellets. Uranium is one of theheaviest elements found in more than traceamounts in nature.There used to be a general perception,which is sometimes still apparent today, thaturanium is a scarce resource. However, it isa metal approximately as common as tin orzinc and it is a constituent of most rocks andeven of the sea. Some typical concentrationsare: (ppm = parts per million) 8.2 .An ore body is, by definition, an occurrenceof mineralisation from which the metal iseconomically recoverable. It is thereforerelative to both costs of extraction andmarket prices.At present neither the oceans nor anygranites are ore bodies, but conceivablyeither could become so if prices were torise sufficiently.Uranium is also radioactive, which the Frenchscientist, Henri Becqurel, discovered wheninvestigating radioactivity. That is under thecorrect circumstances the uranium nucleuscan split, releasing energy and otherparticles. To trigger the fission of a uraniumnucleus it must be struck by a particleknown as a neutron. This particle istemporarily absorbed, making the uraniumnucleus unstable. The nucleus then splits toform 2 smaller nuclei and releases a furthertwo or three neutrons in the process, inaddition to energy in the form of the kineticenergy of the particles and gamma radiation.All the uranium on Earth, unlike the fossilfuels, was forged from lighter elementsduring supernova explosions billions ofyears ago.Table 8-1The Natural Occurrence of UraniumDepositHigh-grade ore bodyLow-grade ore bodyGraniteSedimentary rockAverage in earth’s continental crustSeawaterConcentration2% U, 20,000 ppm U0.1% U, 1,000 ppm U4 ppm U2 ppm U2.8 ppm U0.003 ppm U31


Material from these explosions eventuallybecame incorporated into stars, like our Sunand planets, like Earth. Therefore nuclearpower here on Earth harnesses energy thathas been stored in uranium for over 4.5billion years.Interestingly, in 1972, French scientiststesting nuclear fuel samples found that onewas deficient in the uranium isotope U-235which is the one which undergoes fission(U-238 is stable, 235 and 238 refer to thenumber of protons and neutrons in anatoms nucleus). So where had the missinguranium gone?The uranium sample had come from an areain Central Africa, called Gabon, where thereis a mine at Oklo producing uranium ore.About 2 billion years ago, several, maybe asmany as 20, natural fission reactors startedup in the area, and are believed to have run(operated) for about one billion years,moderated (or controlled) by water seepingdown. Therefore with time the amount ofuranium 235 decreased and the daughterproducts of the reaction were in placeinstead. It would not have happened today,as the amount of U-235 has decreased withtime, due to the natural radioactive decayprocesses which occur all the time.Having established that the uranium iscontained in the rocks, which make up ourplanet Earth, how is it extracted anddeveloped for use in the nuclear reactor?Unlike oil, gas and even coal, where it ispossible to extract the fossil fuel and withminimum of processing deliver it to the endcustomer at very high recoveries, theextraction of uranium from the ore is a moredifficult and indeed costly process.For example, since the fifteenth centurymany miners who had worked undergroundin the mountains near the present borderbetween East Germany and the CzechRepublic contracted a mysterious illness,and many died prematurely. In the late 1800sthe illness was diagnosed as lung cancer,but it was not until 1921 that radon gas wassuggested as the possible cause.Although this was confirmed by 1939,between 1946 and 1959 much undergrounduranium mining took place in the USAwithout the precautions which might havebecome established as a result of theEuropean experience. In the early 1960s ahigher than expected incidence of lungcancer began to show up among minerswho smoked.The cause was then recognised as theemission of alpha particles from radon and,more importantly, its solid daughter productsof radioactive decay. The miners concernedhad been exposed to high levels of radon10-15 years earlier, accumulating radiationdoses well in excess of presentrecommended levels. Today all uraniummining takes place in well-ventilatedunderground mining or above the surfaceto prevent the re-occurrence of theoverexposure to radon.After mining is complete most of the orebody, with virtually all of the radioactiveradium, thorium and actinium materials willend up in what is known as the tailings dam.Hence radiation levels and radon emissionsfrom tailings will be significant. In the unlikelyevent of someone setting up camp on topof the material, they could eventually receivea radiation dose exceeding internationalstandards, just as they could from outcropping ore bodies. Therefore, the tailingsneed to be covered over with enough rock,clay and soil to reduce both gamma radiationlevels and radon emanation rates to levelsnear those naturally occurring in the region.A vegetation cover can then be established.Measures will be in place to prevent thetailings becoming dust and being exposedto winds for distribution.As the uranium (U-235) is only present attypically 0.72% of the ore body this meansfor every 720 grams of U-235 produced itrequires a minimum of 1,000, 000 grams ofrock to be dug out. Most of this as describedabove ends up in the tailings dump.Therefore, starting in uranium mines such asOlympic Dam or Ranger in Australia or thenorthern Saskatchewan mines of Canada,the uranium containing ore is mined andmilled to produce uranium in the form ofuranium oxide concentrate. It is a mixture oftwo oxides, commonly known as U3O8.This material, a khaki-coloured powder, isshipped to customers. It has the sameisotopic ratio as the ore, where uranium-235(U-235) is present to the extent of about 0.7percent. The rest is a heavier isotope ofuranium - U-238 (with traces of U-234).Most reactors, including the common lightwater type (LWR) cannot run on naturaluranium, so the proportion of U-235 mustbe increased to about 3.5 percent. This iscalled enrichment. Canadian reactors useun-enriched uranium.Enrichment is a fairly high-technologyphysical process, which requires the uraniumto be in the form of a gas. The simplest wayto achieve this is to convert the uraniumoxide to uranium hexafluoride, which is a gasat little more than room temperature.This form of uranium is commonly referred toas UF6 or “hex”. Hence the first destinationof uranium oxide concentrate from a mine isa conversion plant where it is purified andconverted to uranium hexafluoride.The UF6 is then fed to an enrichmentprocess which increases the proportion ofthe fissile U-235 isotope. In the processabout 85% of the natural uranium feed isrejected as “depleted uranium” or “tails”(mainly U-238) which is stockpiled.Thus, after enrichment, about 15% of theoriginal quantity is available as enricheduranium containing about 3.5 percent U-235.The enrichment takes place in either the USor the UK.The enrichment methods now in use arebased on the slight difference in atomicmass of U-235 and U-238. Much of theinstalled capacity relies on the gaseousdiffusion process, where the UF6 gas ispassed through a long series of membranebarriers which allow the lighter moleculeswith U-235 through faster than the U-238ones. More modern plants use high-speedcentrifuges to separate the molecules of thetwo isotopes.Enriched uranium then goes on to a fuelfabrication plant where the reactor fuelelements are made. The UF6 is convertedto uranium dioxide, a ceramic material,and formed into small cylindrical pelletsabout 2 cm long and 1.5cm in diameter.The pellets are loaded into zirconium alloyor stainless steel tubes about 4 metreslong to form fuel rods. These are assembledinto bundles about 30-cm square to formreactor fuel assemblies. Fuel assembliesof this type are used to power theUS-developed light water power reactor,currently the most popular design.A 1000 MWe reactor has about 75 tonnesof fuel in it.32


8.2 The Use of Uranium forGenerating ElectricityThe use of uranium as a fuel source forgenerating nuclear power began in earnest in1945, following the end to the Second WorldWar and the dropping of the nuclear bombsover Japan.The use of nuclear power has grown steadilyfrom that time. In 1973, it accounted for0.9% of the worlds total primary energyproduction, while in 2000, that had increasedto 6.8%. 8.3 Furthermore, that represented17% of the worlds total electricity supply asshown in Table 8.5.Table 8-2Regional Sharesof Nuclear Production(IEA Key Energy Statistics)Geographical Region 1973 2000OECD 92.8% 86.6%Non-OECD Europe 0.0% 1.1%Former USSR 5.9% 8.4%Asia* 1.3% 2.2%Other** 0.0% 1.6%Total (TWh) 203.0 2592.0* Excludes China** Includes Africa, Latin America and ChinaThe following tables give some keyinformation regarding the main producersinstalled capacity and percentage of theworld’s electricity generation coming fromnuclear power.Table 8-3Producers of ElectricityProducers TWh % ofWorld totalUnited States 800 30.9France 415 16.0Japan 322 12.4Germany 170 6.6Russia 131 5.1Korea 109 4.2United Kingdom 85 3.3Ukraine 77 3.0Canada 73 2.8Spain 62 2.4Rest of the World 348 13.4World 2592 100.00Table 8-4Table 8-5Installed CapacityNuclear Domestic Electricity GenerationInstalledGWBy CountryCapacityCountry% of Nuclear Total(Based on firstin Total DomesticUnited States 98 10 Producers) Electricity GenerationFrance 63France 77Japan 44Ukraine 45Germany 21Korea 37Russia 20Germany 30Canada 15Japan 30Korea 13Spain 28United Kingdom 12United Kingdom 23Ukraine 11United States 20Sweden 9Russia 15Rest of the World 51Canada 12World 357Rest of the World 9World 17As mentioned previously there was aperception that uranium was a scarceresource. In the early 1970’s there wasIt can be seen that Australia has asubstantial part (about 28%) of the world’slow-cost uranium, and Canada 15 percent 8.5 .perhaps some justification for this asHowever, there has been very little uraniumanticipated rates of exploitation of knownexploration in recent years on account of thereserves where such that concerns aboutextensive reserves having been discoveredpossible future shortages have some validity.and an expectation that there will be an entryIt is now however quite clear that there arevery adequate reserves to fuel nuclear powerfor the foreseeable future. Consumption forthe next 20 years is likely to be in the rangeof 60-80,000 tonnes per annum, whichimplies over 40 years supply if all costcategories in all classes are concerned.However, given the relatively low impact ofthe cost of uranium on the overall economicsof nuclear power, it can be considered thatthe total potential supply base as indicatedbelow could be in excess of 100 years. 8.4into the commercial market of materialrecycled from nuclear weapons. Militarymaterial is highly enriched in U-235 andtherefore has to be blended with depleted orreacted uranium in order to bring the U-235levels to that required for use in a civiliannuclear power station. For the nuclear fuelmarket this is a big issue as it is estimatedthat 600,000 tonnes of uranium, or roughlyone-third of all uranium cumulativelyproduced since 1945, may at some pointarrive on the market, representing 10 yearstotal production. However, like with goldWith major qualifications outlined in note 8abeing released from the Reserve Banks, it isTable 8.3 gives some idea of our presentanticipated that the uranium will be releasedunderstanding of uranium resources.slowly and that the market will absorb it.Table 8-6Current Uranium ReservesAustralia 863,000 28%Kazakhstan 472,000 15%Canada 437,000 14%South Africa 298,000 10%Namibia 235,000 8%Brazil 197,000 6%Russian Fed. 131,000 4%USA 104,000 3%Uzbekistan 103,000 3%Rest of World 267,000 8%World Total 3,107,000 100%33


Therefore the supply of nuclear fuel can becategorised into 3 stages:• A military era from 1945 to the mid1960’s where the generation of electricitywas incidental to the arms race.• A period of rapidly expanding civil nuclearpower lasting form the late 1960’sthrough to the mid 1980’s. Uraniumdemand picked up as reactor orderswere expanded. Production peaked in1980 and stayed above annual reactordemands until 1985.• An age dominated by inventory overhang,which resulted from a cutback in thebuilding of new capacity and long-termsupply contracts with mines.Also material arrived on to the marketfrom the old Eastern bloc countries.Currently, primary uranium production isrising, supplemented by secondary sources.At present 8.6 there were 441 operational breactors in December 2002, with a further 34reactors under construction c and 29 reactorsplanned d . The uranium requirement worldwide for 2002 was 65,434 tonnes.bcdOperating, connected to theelectricity grid.Construction, the first concrete pouredfor the reactor.Planned, approvals and funding in place.China, Canada, Japan Korea and the formerUSSR countries are the leading nations withreactors under construction, while Japanand Korea are those with most planned(accounting for 21 out of the 29 planned).The others are in Argentina, Romania, Russiaand the Ukraine.The position in the United Kingdom is asfollows. In 1995, the government announcedthat it would privatise its more modernnuclear stations while retaining ownership ofolder stations. In 1996, more modernstations were privatised and British Energybecame the holding company of NuclearElectric and Scottish Nuclear, which mergedin 1998 to form British Energy Generation,the nation’s largest private nuclear generatorand the world’s first wholly privatised nuclearutility. British Energy operates eight nuclearpower stations in the UK. Each stationconsists of two advanced gas-cooledreactors, except Sizewell B, which is amodern pressurised-water reactor.Nuclear power stations were not privatisedsimultaneously with non-nuclear stations.No new plants have been built since 1995.Of the UK’s 33 reactors, 26 are of the oldMagnox design. Six of the Magnox reactorsare being decommissioned, as well as theDounreay prototype fast reactor.The state-owned British Nuclear Fuels runthe remaining Magnox plants. British NuclearFuels operates the Sellafield reprocessingplant, and is one of only two companies inthe world that provides reprocessing andrecycling technologies. The Department ofTrade and Industry’s Nuclear Directorateregulates the British nuclear industry.With respect to the position of the UnitedKingdom, in part because it is the mostpoliticised of all electricity generationtechnologies, future nuclear power capacityis in particular difficult to forecast 8.7 .The difficulty arises form a number of issuessuch as safety, nuclear proliferation, wastedisposal and plant decommissioning.However, as reported in 8.7 , the UnitedKingdom is one country where new nuclearconstruction is thought to be a possibility.However this is only in the high growthscenario which predicts by 2020 that threenew 1000 megawatt units will have beenbuilt and operating by the end of the forecastperiod. This is in contrast to all previousscenarios, which forecast zero building ofnew nuclear reactors.One of the difficulties in forecasting the futurerole of nuclear power is that different partiesoften have opposing views on the subject.For example while the Conservativegovernment was in power in the UnitedKingdom nuclear power was thought to bea viable future contributor to new electricitygeneration. When Labour assumed office itwas assumed that Labours previousopposition to nuclear power would becomethe stated government policy, however, theoption has been left open that nuclear powerwould continue to play a role in the nationselectricity supply. Britain’s support of theKyoto Protocol (See Chapter 14) forced are-evaluation of the nuclear option, ascompliance would be very difficult without it.In 2002 a UK government review of energywas released which called for a nationaldebate on nuclear power and for anexamination of ‘low waste, modular designs’of nuclear reactors. There have been severalcalls from within the industry for thegovernment to do more to promote the useof nuclear power for electricity generation.However, two reports completed by thegovernment in 2001 pointed out that nuclearpower was much more expensive than windor biomass and that increased energyefficiency and combined heat and powerwere preferable options. Concerns overnuclear proliferation and terrorism postSeptember 11th, 2001 may also havecontributed to the decision making.Since the reform of the UK electric powermarket, which commenced in 1989, ourelectricity market has developed into one ofthe most competitive in the world, whichdoes not figure well for the future of thenuclear industry. For example in 1995 a UKgovernment white paper concluded that in acompetitive private market no-one couldinvest in new nuclear capacity and indicatedthat government subsidies were notappropriate for construction of new plants 8.8 .8.3 Generating Electricity UsingNuclear PowerIn Section 8.1 the natural occurrence ofuranium was discussed, and uranium, withexceptions like Oklo, releases its energy veryslowly and does not generate much heat.However, the use of nuclear fission speedsup the release of energy.In nuclear fission, the nuclei of a heavyelement splits by being struck by a neutronand releases its energy. Some of the energyis released in the increased speed of theparticles (their kinetic energy) and in gamma(very high-energy) radiation. In a nuclearreactor the reaction is controlled so that,on average, one neutron from each fissionevent leads to the release of another.Therefore the neutron flux within the reactorremains constant and the energy is releasedat more or less a steady rate. If you allowmore than one neutron from each event tocause further fission then the neutron fluxincreases and the power output goes up 8.9 .This is not a desirable situation as it can leadto the nuclear chain reaction getting out ofcontrol. This is prevented by the use of‘control’ rods, which are interspersed withthe uranium rods. These regulate the rate offission by soaking up the neutrons and canbe raised or lowered to keep the release ofenergy steady. They are made from aneutron absorbing material such as boron orcadmium and when they are lowered intoposition soak up the neutrons.34


Control rodsFigure 8-1The Structure of a Nuclear Powered Station 8.10Concrete pressure vesselSteam generatorFuel elementsGraphite moderatorRaising them up speeds up the productionof neutrons and hence the amount of energyproduced. Reactors have what is known asa fail safe design in that the control rodsautomatically drop down into the reactorcore in an emergency, shutting the reactordown as soon as possible.The other material in the reactor is knownas the moderating material, which slows thefast moving neutrons, which are releasedduring fission, and enables them to reactmore efficiently with the uranium, makingfission more probable. Moderating materialsinclude water (including what is known asheavy water) or graphite blocks.Surrounding and circulating through the coreis a coolant, which carries away the heat.In the UK gas cooled reactors such asMagnox, and the advanced gas cooledreactors (AGR’s) use carbon dioxide (CO2)as a coolant. Pressurised water reactors,such as that at Sizewell B, use water.Sometimes the water is used as both acoolant and moderator. After it is heated inthe core of the reactor the coolant ispumped through a heat exchanger whereis transfers its energy to water, creatinghigh-pressure steam. The steam is used toturn turbines, which drive a generator.This part of a nuclear power station is likeany other part of the conventional thermalelectricity-generating stations. However, asmost nuclear power stations have their coreat temperatures around 300 o C, and arecooled by water at around 20 o C, thetemperature difference between the twois smaller than the other thermal generatingmethods. Therefore the efficiency, or thatpercentage of energy, which can bediverted into a useful form such as electricity,is smaller.Finally, as nuclear reactors can take days tostart up and switch off they are used as baseload applications and are kept running atsteady state of months on end (see chapter7 on the different generating methods usedduring a twenty four hour period).As has been discussed, the amount ofcarbon dioxide emitted by the nuclear powergenerating stations is zero, along with mostof the other potentially damaging gases.However, during fission, as has beenmentioned, gamma radiation is emitted andthe fission products are highly radioactive.As it is used up the uranium-235 becomesincreasingly dilute, and eventually cannotsustain the chain reaction.Therefore the nuclear fuel is termed as‘spent’ and has to be removed from the coreof the reactor. However, the spent flue rodsare now surrounded by a number of highlyradioactive elements whose disposal needsto be handled very carefully. Also othermaterials which have come into contact withthe uranium need to be treated as well.This radioactive waste is produced in solid,liquid and gaseous forms by a diverserange of activities within the generation ofelectricity. It arises from the routine operationof nuclear reactors; the reprocessing ofspent nuclear fuel and the decommissioningof reactors. Significant quantities are alsoproduced in defence and researchestablishments, by some engineeringindustries and in medical diagnosis andtreatment. Some 7,000 sites in Great Britainproduce radioactive waste in the course ofproviding products and services 8.11 .In the UK, radioactive wastes are classifiedinto three main categories: high, intermediateand low level waste (HLW, ILW, LLWrespectively), according to their levels ofradioactivity and heat-generating capacity.LLW is defined as waste material that has aradioactive content above 400 becquerels 8.12per kilogram (Bq/kg), but not exceeding35


4 million Bq/kg of alpha activity or 12 millionBq/kg of beta/gamma activity.The radioactive content of ILW is above thethreshold for LLW, but not sufficiently greatto result in significant heat output from thewaste. HLW is highly radioactive andconsequently generates significant heatsuch that this has to be taken into accountin managing the waste.Figure 8-2The Nuclear Fuel Cycle 8.13 36LLW accounts for about 70% of the volumeof radioactive waste produced in the UK, butonly a small fraction of the total radioactivity.LLW has a wide range of origins. It consistsof materials such as protective clothing,packaging, scrap metal, worn out ordamaged equipment, and concrete,rubble and soil from building demolition.Although the use of nuclear fuel for electricitygeneration has increased the level of LLWis reported to have decreased.In the UK some industrial low level wasteis incinerated, but most solid LLW,including the incinerator ash, is disposedof at the Drigg repository in Cumbria,which is owned and operated by BNFL.Since 1988 Government policy has requiredthat, where appropriate, LLW undergoessupercompaction to minimise volumes.It is then grouted into standard steelcontainers, which are stacked into purposebuilt, open air concrete structures at Driggknown as ‘vaults’. As each of these is filleddome-shaped water resistant cap is placedover it to stop rainwater entering.This minimises the build up of leachates,which could contaminate groundwater.After capping the vault is covered withtopsoil and landscaped. It is predicted thatDrigg has sufficient capacity for LLW untilthe middle of the 21st century.The discharge of low level radioactive liquidand gaseous wastes to the environment isregulated by strict authorisation conditionsdesigned to limit public exposure to safelevels. Liquid LLW is filtered and, wherenecessary, passed through an ion exchangeprocess before dilution and eventualdischarge to sea. Gaseous wastes,which have a low radioactive content,are filtered to remove radioactive particlesbefore discharge to the atmosphere.ILW accounts for around 30% of allradioactive waste arising by volume.For radiological protection purposes it usuallyrequires some shielding and containment.ILW mainly consists of solids and liquids fromnuclear fuel fabrication and reprocessingfacilities and nuclear power stations.Before ILW is transported or disposed of,it usually undergoes a process ofsolidification which is known as ‘conditioning’or ‘encapsulation’.Conditioned ILW is held in shielded stores onlicensed sites at nuclear power stations or atthe BNFL Sellafield site. This interim storageis in anticipation of the eventual constructionof a deep underground repository in the UKfor the disposal of ILW and some LLW.Such a repository would be based onthe multi-barrier concept where waste iscontained in stainless steel drums orconcrete containers and a cement grout orback fill packed around the containers.This level of shielding and containment isdesigned to isolate the radioactivity fromthe environment for several thousand years,by which time most of the radioactivity wouldhave decayed.HLW contains around 95% of theradioactivity in wastes from the nuclear cycle,but it accounts for less than 1% of all UKradioactive waste by volume. It arises fromthe reprocessing of spent nuclear fuel.About 96% of the spent fuel is uranium anda further 1% is plutonium, and both thesecomponents are separated out for recyclingas new fuel. The remaining 3%, consisting offission products and some other heavymetals such as americium and neptuniumfrom the nuclear reactions, become highlevel liquid waste. At all stages of thetransportation and handling of HLW, specialprecautions are employed to minimise therisk of escape of radioactivity. HLW is heavilyshielded within secure containers, whichmeet international standards of design andconstruction. The management of HLW isprimarily the responsibility of BNFL.


9The use of Air and Waterin Electricity GenerationThe other two main ‘raw materials’ used in electricitygeneration are air (with the exception of the nuclear industry)and water, both of which are passed through in huge volumes,and returned to the environment, in an altered condition.The issue of both gaseous and aqueous emissions will be dealtwith in the following Chapter.9.1 The Use of Air in theCombustion ProcessCombustion is a chemical process in which asubstance reacts rapidly with oxygen andgives off heat. The reacting substance iscalled the fuel and the source of oxygen theoxidiser. The fuel, as we have seen, can be asolid for example coal, liquid, for example oil,or a gas. The oxidiser likewise can be asolid, liquid or gas.During the combustion new chemicalsubstances are created from the fuel andthe oxidiser. These substances are called theexhaust. Most of the exhaust comes fromthe chemical combinations of the fuel andoxygen. When a hydrocarbon-based fuel,like coal, oil or natural gas burns the exhaustincludes water and carbon dioxide.But the exhaust can also contain chemicalcombinations of other elements presentduring combustion. If, for example, as in thepower generation process, the fuel is burntin air, air contains approximately 21% oxygenand 78% nitrogen. Therefore the exhaustcan contain nitrous oxides (NOX). If the fuelcontains sulphur, like in coal and oil, then thesulphur will be converted to sulphur dioxide.If there is insufficient oxygen present tocompletely combust the fuel, carbon,hydrogen and carbon monoxide may bepresent in the exhaust, along with possiblysome liquid components and even somesolids, for example, carbon in the formof soot.During the combustion process as thefuel and oxidiser are turned into exhaustproducts, heat is generated. Heat is alsorequired to start the combustion process.As heat is required to start the combustionprocess, and the combustion process itselfproduces heat, once the process is started,the heat from the combustion will keepthings going.Therefore for combustion to occur yourequire three things, a fuel to be burned, asource of oxygen, in this case air, and asource of heat. As a result of combustion,exhausts are created and heat is released.Adjusting the amount of fuel or oxygenavailable or the source of heat controls thecombustion process.In order to maximise the efficiency of thecombustion process, and to minimisethe amount of reduced gases formed(for example, carbon monoxide) the amountof oxygen (air) required for the theoreticalcomplete combustion, is known as thestoichiometric amount. Typically more air issupplied than the stoichiometric amount, theexact amount being dependent on the localconditions, for example, amount of ashpresent. In the mass balance, thestoichiometric amount is used, based onthe carbon content of the fuel.In the UK the average amount of air usedfor the oxygen content is 8084 litres/kWh,with approximately 1x1015 litres of air,0.21x1015 litres of oxygen, being usedin 2000.37


9.2 The Use of Water inCombustion ProcessesWater is also used in the combustionprocess. Thermal electric power generationuses the heat released from fossil fuels(coal, oil or natural gas) or uranium (oxide) toproduce steam from water to drive a turbinecoupled to a generator. The power plants areall types of heat engines in that energy flowsfrom a high-temperature source, such as areactor core in a nuclear power station, to acooler ‘sink’ usually a reservoir of coolingwater. The greater the temperature differencebetween the two, the greater the percentageof energy that can be diverted into a usefulform such as electricity. This is also knownas the operating efficiency. Coal fired powerstations have their heat source around550 o C, while nuclear power stations havetheir reactor core around 300 o C.Therefore the efficiency of the coal-poweredstations is higher than the nuclear poweredstations where about one-third of the energyreleased by the fission process ends upas electricity.The rest is wasted as heat. Thermal electricplants also require a supply of water to cooland condense the exhaust steam fromthe turbine.In the UK around 10,000 million m 3of water is passed through the powergenerating stations each year, after beingabstracted from both fresh and tidal waters.99.13% is returned to the original sourcewith some minor modifications, generallybeing slightly warmer and having somechemicals from such activities aspreventing fouling in the heat exchangers.These modifications will be covered in thefollowing chapter. Therefore on average allbut 0.87% returns to the extraction source;the 0.87% is generally released as steam.The appearance of steam around powerstations can be deceptive with respect to theamount being released. 46.50% of the waterused in the power generation applications isfrom freshwater, while the balance, 53.50%,is from seawater sources.38


10ThisChapter examines the issue of solid, liquid and gaseousemissions arising from the generation of electricity.Emissions10.1 Solid EmissionsIn terms of solid emissions the key issuesfor the electricity generation industry are theresponsible management of the residual ashfor the coal burning and the radioactivewaste from nuclear generation.At present around 200 million tonnes ofhousehold and business waste aregenerated in the UK each year, of whicharound 60% goes to landfill. Sustainablewaste management seeks to minimise thewaste generation and maximise re-use,recycling and energy recovery. Some specialwastes, and this would include radioactivewaste, have special handling anddisposal requirements.The 1996 landfill tax was introduced toencourage recycling and other non-disposaloptions. At 1999 inert waste was taxed at £2per tonne and ‘active’ waste, that is wastewith pollution potential at £10 per tonnerising to £14 by 2004. A tax credit schemeencouraged operators to redirect someof the tax revenue into environmentalprogrammes and projects.10.1.1 Ash from Coal-basedGenerationPulverised fuel ash (PFA) and furnace bottomash (FBA) are inevitable by-products of coalfiredgeneration due to the incombustible,inorganic material present in coal. Therelease of trace elements to the environmentas a result of the coal-fired generation is anarea of increasing concern. Knowledge ofhow the trace elements are distributedamongst the flue gas, fly ash and bottomash would be vital for developing futurecontrol practices.Most of the trace elements of interest areassociated with the coal mineral matter,but some are also associated with the coalorganic matter. There are four main groupsof mineral phases:1 Oxides, carbonates andmonosulphide (MS)For example, arsenic is associated mainlywith oxides and organic matter, whileselenium is associated with the pyriticmaterial. Mercury, arsenic, selenium, nickel,lead, copper and zinc all tend to beassociated with the sulphide minerals andorganic matter in coal. Elements associatedwith either the pyrite or the organic matter inthe coal tend to volatilise and exit with theflue gas, often as a condensate on thesurface of the fine ash particles. This is veryimportant from the viewpoint of both controlsof the trace elements and subsequent issuesin landfill, for example leaching of metals intothe soils.However, ash produced from the samesource of coal and with a very similarchemical composition can have significantlydifferent ash mineralogies depending on thecoal combustion technology used. Thereforethe leaching behaviour, that is the behaviourin contact with water, can vary significantly.The amount of crystalline material versus theglassy phase material depends largely on thecombustion and glassification process usedat a particular power plant. When themaximum temperature of combustion isabove approximately 1200 o C and the coolingtime is short, the ash produced is mostlyglassy phase material. Where boiler designor operation allows a more gradual coolingof the ash particles, then crystalline phasecalcium compounds are formed.The factors which affect the hydration,and leaching properties of fly ash are:• Relative proportion of the sphericalgassy phase and crystalline materials,• The size distribution of the ash,• The chemical nature of the glass phase,• The type of crystalline material and thenature and• The percentage of unburned carbon2 Pyrite3 Silicates4 Organic matter39


The primary factors, which influence themineralogy of the coal fly ash, are:• Chemical composition of the coal• The coal combustion processincluding coal pulverisation, combustion,flue gas clean up and fly ashcollection operations• The additives used, including oiladditives for flame stabilisation andcorrosion control additives.To summarise, the minerals present in thecoal dictate the elemental composition of theash produced, but it is the boiler design andoperation which dictate the mineralogy andcrystallinity of the ash itself. Furthermore, theultimate leaching characteristics of the ashwill also be dictated by the soil in which it isin contact with. Some of the metals leachedfrom the ash will find their way into the waternetwork, which others will be absorbed onthe clay minerals of the soil.PFA and FBA are both classified as inert andcan be recycled as secondary raw materialsfor building and construction work. This inturn reduces the need for quarrying ofbuilding materials with its associatedenvironmental impacts. Some ash is alsoused to reclaim derelict land. Unused ash isdisposed of as inert waste to landfill sites.The following table shows the estimatedamount of fly ash produced within the UnitedKingdom between 1995 and 1999. Due tothe change in the generating mix away fromcoal and towards the use of gas, the amountof flyash fell by 34% over the four-yearperiod. During the same period thepercentage recycled rose from 47% to 54%,but as the overall amount produceddeclined, this would suggest that thedemand for flyash has also fallen.Table 10-110.1.2 Radioactive WasteRadioactive waste is registered under theRadioactive Substances Act1993, and byconditions imposed in nuclear site licenseunder the Nuclear Installations Act 1965.It is classified as low, intermediate or highlevel depending on its concentration ofradioactivity, and can be solid, liquid orgaseous. The bulk of the solid waste is lowlevel, items such as protective clothing,paper towels, packaging materials andworn-out equipment. Where possible theamount is reduced by compaction orincineration before it is sent to the UK’sdesignated repository at Drigg in Cumbria.While the amount of low level waste createdby the generating process is falling in linewith improved practise, the overall amountbeing stored each year has started toincrease due to increased amounts ofdecommissioning waste being generated.Intermediate waste includes irradiatedequipment removed from reactors duringmaintenance and chemical sludges fortreatment of radioactive effluent. As theamount produced is relatively small, it iscurrently stored on station sites in speciallyshielded stores pending final disposal in apurpose built repository.High level waste arises from the reprocessingof spent fuel at BNFL Sellafield where it isstored under authorisation from theregulatory bodies, but the nuclear generatorsremain responsible for the waste pendingfinal disposal.10.1.3 Other Solid WastesA by-product of the flue gas desulphurisationplant is gypsum (calcium sulphate). In 1999over 500,000 tonnes of gypsum wereproduced and almost all of this was sold forplasterboard manufacture.It is furthermore estimated at 98% of metalwaste / scrap was recycled.And finally, due to the Codes of Practise forimplementing the New Roads and StreetWorks Acts 1991, which effectively preventsspoil from roadwork’s being used to backfill ahole or trench, electricity companies have todispose of an estimated 500,000 tonnes ofroad spoil per year to landfill. This is theclassified as inert waste.The Table 10-2 gives the amount of solidwaste generated by each of the four mainelectricity generation methods, by kWh/kgand in tonnes per annum.10.2 Liquid Emissions10.2.1 Water Abstracted for CoolingAs stated in Chapter 9, thermal electricgenerating facilities make electricity byconverting water into high-pressure steamthat drives turbines. Once water has gonethrough this cycle, it is cooled andcondensed back to water and then reheatedto drive the turbines again. The process ofcondensation requires a separate coolingwater body to absorb the heat of the steam.These condenser systems typically consist ofbanks of thousands of one-inch diametertubes, through which cooling water is run,and over which the hot steam and wateris circulated.Two cooling technologies are in use today:• Closed-cycle systems discharge heatthrough evaporation in cooling towersand recycle water within the power plant.The water required to do this iscomparatively small since it is limited tothe amount lost through the evaporativeprocess. Because of the expenseassociated with closed-cycle cooling,once-through systems are farmore common.• Once-through systems require theintake of a continual flow of coolingwater. The water demand for theonce-through system is 30 to 50 timesthat of a closed cycle system.Ash from Fossil Fuel GenerationFBA 1995/96 1996/97 1997/98 1998/1999Produced 2.2 1.7 1.4 0.8Sold for Use 2.1 1.6 1.4 0.8Landfilled 0.1 0.1


Table 10-2Solid Waste Produced by the Different Electricity Generation Methods 10.1Units Solid Waste Type Coal-based Oil-based Gas-based Uranium-based TotalGeneration Generation Generation Generationkg/kWhe Other waste 0.04154 0.00056 0.00047 0.00090 0.04346kg/kWhe Radio active waste 0.00015 0.00169 0.00001 0.00001 0.00185kg/kWhe Waste to incinerator 0.00002 0.00265 0.00000 0.00000 0.00268kg/kWhe Other waste 0.00019 0.00368 0.00000 0.00001 0.00389kg/kWhe Ash 0.01662 0.00000 0.00000 0.00000 0.01662Tonnes Inert waste 56,027,899 271,473 789,369 434,842 57,523,583Tonnes Other waste 4,861,723 1,346 60,320 76,250 4,999,639Tonnes Radio active waste 17,590 4,072 1,072 551 23,286Tonnes Waste to incinerator 2,590 6,409 148 407 9,554Tonnes Other waste 22,721 8,888 378 992 32,979Tonnes Ash 5,694,804 0 0 0 5,694,804As stated most electric power stationsrequire water to operate. Since greater than98% of the water used in power plants isreturned to its source, distinctions are madebetween water use and water consumption.Water use is a measure of the amount ofwater that is withdrawn from an adjacentwater body (lakes, streams, rivers, estuaries,etc.), passes through various componentsof a power plant, and is then ultimatelydischarged back into the original water body.Environmental concerns surrounding wateruse centre around any chemical or physicalalteration of the water body and any impactsthese changes may have on the plants, fishand animals who reside in the ecosystem.Water consumption refers to water suckedup in power plant operations that is lost,typically through evaporation. The primaryconcerns surrounding water consumptionis how best to utilise this essential resource,especially in areas where water is inshort supply.The thermoelectric power generationcategory includes water-use activities,such as: withdrawals from ground andsurface water; deliveries from watersuppliers; consumptive use from coolingtowers, cooling ponds, and steamventing; water and wastewater treatment;and return flow (figure 11). The water in thesteam cycle usually is treated at the powerplant before use to reduce impurities thatwould cause build-up of mineral residueinside the boiler.The cooling water, which comes from lakes,rivers, or oceans, always is separate from theboiling water/steam (non-contact coolingwater) and can be:(1) Discharged directly to the ocean, lake,or major river (once-through cooling),(2) Discharged to a canal, cooling pond,or cooling tower before returning to theriver, or(3) Sent to a cooling pond or cooling towerbefore being recycled.Although most of the water used inthermoelectric plants is cooling water forcondensing the steam, water is required for(1) makeup water to replace the water lostas steam,(2) blow down (purging) of boilers, washingof stacks, plant and employee sanitation,water and wastewater treatment,(3) And in nuclear plants, to keep thenuclear fuel from overheating and melting.Water from non-cooling uses goes to either apublic wastewater treatment facility or theplant’s onsite wastewater treatment facility.Storm water from roof drains and area stormsewers also may be treated at thewastewater facility and may cause dischargevalues to be higher than expected.The volume of water that is required in thethermoelectric power generation and therate of consumptive use are dependenton whether cooling towers are used.Some plants built on an ocean or large riversimply pump in large amounts of water tocool the steam. This cooling water then isreturned back to the ocean or river.The water is somewhat warmer than whenit entered the plant. If the cooling water isdischarged to a significant water body, suchas an ocean, lake, or major river, the watercan be discharged directly. However, if thewater is discharged to a river, its return to theriver may be delayed by routing it through acanal or cooling pond first. Some plantsrecycle cooling water. Cooling ponds andtowers are used to transfer the heat in thecooling water to the air.A cooling pond is a shallow reservoir having alarge surface area for removing heat fromwater. The surface area exposed to the airmay be increased through the use of spray41


nozzles. Cooling ponds are used where landis relatively inexpensive, cooling water isscarce or expensive, or where there are strictthermal loading restrictions in place.If cooling ponds are used, water in the pondcan be reused, thus reducing the overallwater-withdrawal requirement.A cooling tower is designed to remove heatby pumping water up into the tower andallowing it to fall down inside the tower.Air comes in from the sides of the tower andpasses by the falling water. As the air passesthe water, it exchanges some of the heat andevaporates some of the water. This heat andevaporated water flow out the top of thetower is in the form of a fine cloud-like mist.The cooled water is collected at the bottomof the tower and pumped back into theplant for reuse. Cooling towers are usedwhere land and (or) water are expensive,or regulations prohibit the return ofonce-through cooling waters.extraction source; the 0.87% is generally However, the electricity supply industryreleased as steam. The appearance ofaccounted for 94% of all abstractions fromsteam around power stations can betidal waters, and when both tidal anddeceptive with respect to the amount being non-tidal are accounted for, the UK electricityreleased. 46.50% of the water used in the industry was responsible for 53%, with thepower generation applications is frompublic water supply the second largestfreshwater, while the balance, 53.50%,abstractor at 28%.is from seawater sources.In 2000 10.2 the public water supply andelectricity supply industry accounted for 77%of all inland water abstracted, and was justabout evenly split between the two sectors.Figure 10-1Water Use and consumptionin a Typical Thermoelectric Power Generating PlantThere are two primary types ofthermoelectric plants-fossil fuel plantsand nuclear plants. Although there are manysimilarities between them, there are someimportant differences that affect how eachplant uses water. In fossil fuel plants, coal,natural gas, or oil are burned to provide theheat necessary to turn the water into steam.Biomass or solid waste fuel types areincluded with fossil fuels. Water is requiredto take care of the ash waste created duringcombustion. This includes both maintainingthe stacks and carrying the waste ash awayfrom the plant. In nuclear plants, water is notrequired for ash disposal but is needed tokeep the nuclear material from overheatingand melting.The thermoelectric power generationwater-use data are the rate of (1) withdrawalby source; (2) deliveries from public watersupply, (3) evaporation, (4) return flow,and (5) recycled water. The powergenerationvalues also are collected forquality assurance.To recap, in the UK around 11503705 millionlitres of water is passed through the powergenerating stations each year, after beingabstracted from both fresh and tidal waters.99.13% is returned to the original sourcewith some minor modifications, generallybeing slightly warmer and having somechemicals from such activities as preventingfouling in the heat exchangers. Thereforeon average all but 0.87% returns to the42


10.2.2 The Role of the Condenser(in Energy Efficiency)The thermodynamic cycle of conventionalthermal power plants obeys Carnot’sprinciple.The operation of power plants is governedby Carnot’s principle. The heat source,the boiler, provides the energy required forwater vapourisation. The cold source, thecondenser, condenses the steam coming outof the low-pressure turbine. One of the mainEfficiency levels reach about 40% forcharacteristics of a power plant, from theconventional new design but can achievetechnical and economic standpoints, is its47% in advanced design and under veryspecific consumption; in other words,favourable climatic conditions in particularthe amount of heat needed to produce onewhen cooling water conditions are suitablekWh of electrical energy. This specific(once-through cooling system), even withconsumption results from the thermal cyclehard coal firing. The result is that nearlybalance as shown in Table 10-3.45% of the amount of energy provided bycombustion must be dissipated at thecondenser level. The condenser is the keypoint of the facility. Regardless of the modeof cooling adopted, it is in fact one of themain interfaces between the power plant andthe surrounding environment.A look at the thermal cycle balance showsthat a significant percentage of the heatgenerated is ‘lost’ in the condenser.In addition, this energy cannot be recoveredbecause its energy is low. New generationsystems, especially combined cycles(or gas-steam turbines), make it possible toThe efficiency and availability of a powerobtain higher efficiencies, sometimes evenplant depends to a great extent on themore than 55%. The heating and flow rate ofintegrity and cleanness of the condenser.the water in the condenser depend on theThese are reasons why specific solutionsinstalled capacity; typically a 250MW stationhave been adopted for a long time now:requires 6 to 10 cubic metres per secondcontinuous mechanical cleaning by foamwith an accompanying temperature rise inballs, corrosion-resistant alloys, such astitanium and stainless steel, etc. Also coolingthe condenser of between 7 to 12 o C.water treatment systems have beendeveloped and are in operation, in particularfor circulating cooling systems.Table 10-3Simplified Balance of a Thermal CycleEnergy transformation Energy % Efficiency(kj) (%)Energy from combustion 9000 100 100Steam generator loss 1050 -11.7 88.3Condenser ‘loss’ 4200 -46.5 41.8Feed water heating -2000 -22.2 (Looping)Turbogenerator losses 65 -0.75 41.05Power supply of auxiliaries 65 -0.75 40.3Loss in main transformer 25 -0.2 40.1Overall efficiency of the facility - - 40.110.2.3 The potential environmentalimpacts of cooling systems.The heat releases at the cold source mainlyconcern 2 receiving environments, namely airand water. It can be argued that via variousnatural processes for example, evaporation,conduction or radiation, the ultimate heatsink is the atmosphere. The trend in the UKover the past 5 years has been a decreasein the net amount of water lost throughevaporation, as the trend towards the use ofgas rather than coal to generate electricitycontinued. Some of the new gas-firedstations use air-cooled condensers, ratherthan water-cooling.The main atmospheric modification is theformation of evaporation fog, in the form ofartificial clouds, in the area close to therelease. It should be noted that thetemperature of formation or disappearanceof evaporation fog is higher above salt waterthan soft water. This can result in a reductionof sunshine and light in the vicinity of thepower plant itself.The following procedures all can occurduring routine operations and maintenanceof power plants and impact on the waterquality returning to the abstract sources.Boiler blow down: This waste streamresults from periodic purging of the impuritiesthat become concentrated in steam boilersystems. These pollutants include metalssuch as copper, iron and nickel, as well aschemicals added to prevent scaling andcorrosion of steam generator components.Coal pile run-off: This waste stream iscreated when water comes in contact withcoal storage piles maintained on the powerplant site. While most piles are kept covered,active piles used to meet the power plantsimmediate needs are often open to theelements. Metals and other naturallyoccurring contaminants contained in coalleach out with the rainfall and are depositedin nearby water bodies.43


Cooling process wastes: Water used forpower plant cooling is chemically altered forpurposes of extending the useful life ofequipment and to ensure efficient operation.Demineralised regenerants and rinses arechemicals employed to purify waters used asmakeup water for the plant’s cooling system.Cooling tower blow down containschemicals added to prevent biologicalgrowth in the towers and to preventcorrosion in condensers.Boiler cleaning wastes: These wastesderive from the chemical additives intendedto remove scale and other by-products ofcombustion.Thermal pollution: Thermal plants createor use steam in the process of creatingelectricity requires water for cooling.This water typically comes from adjacentwater bodies or groundwater sources andis discharged back into the water body atsignificantly higher temperatures, on averagearound 7 o C higher. By altering thetemperature in the “mixing zone,” thedischarge of thermal wastewater can haveboth negative and positive effects onaquatic life.On the plus side, the warmertemperature water may create morefavourable feeding and breeding conditionsfor certain species located near the powerplant’s water source. However, when thepower plant is suddenly shut down forroutine maintenance or unplanned outage,the resulting wide swing to coldertemperatures can be lethal to sensitive fishpopulations. Indeed the higher temperaturescan also have a negative effect by encouraginghigher than normal growth rates atunseasonable times of year.10.3 Gaseous EmissionsElectricity is essential for economic andsocial development and simultaneouslyprovides the most efficient means of utilisingmany sustainable forms of energy. It istherefore the key to “sustainabledevelopment” which aims to maintaineconomic growth and social progress whilstprotecting the environment and conservingnatural resources. The provision of electricityin poorer nations was a key issue at the UNWorld Summit on Sustainable Development,which was held in Johannesburg in 2002.Indeed the main focus of the ‘NEPAD’ whichis the New Partnership for AfricanDevelopment places the electrification ofAfrica at the heart of its agenda.However, on the other hand, the combustionof fossil fuels gives rise to emissions of anumber of gases, but primarily carbondioxide, CO 2, which, due to their increasingconcentration in the atmosphere, have beenimplicated in the enhanced warming of theatmosphere and in the global climatechange. The electricity supply industry is themajor consumer of fossil fuels (followed bythe transport industries) and as a result is themajor producer of the greenhouse gasemissions.Increasing atmospheric concentrations ofgreenhouse gases originating from mansactivities are leading to an enhancedwarming of the atmosphere and ultimatelyto climate change. The major greenhousegases are carbon dioxide, methane andnitrous oxide all of which have both naturaland anthropogenic (that is man-made)sources.Table 10-4Liquid Waste Produced by the Different Electricity Generation Methods 10.3Units Liquid Waste Type Coal-based Oil-based Gas-based Uranium-based TotalGeneration Generation Generation Generationkg/kWhe Chloride 0.01475 0.01125 0.00023 0.00027 0.02650kg/kWhe Sulphate 0.01023 0.00056 0.00015 0.00201 0.01294kg/kWhe Phosphate 0.00009 0.00022 0.00006 0.00017 0.00054kg/kWhe Ammonia 0.00000 0.00002 0.00000 0.00001 0.00003kg/kWhe Oils-freshwater 0.00000 0.00000 0.00000 0.00000 0.00000kg/kWhe Oils-seawater 0.00002 0.00037 0.00000 0.00000 0.00039kg/kWhe Zinc 0.00002 0.00000 0.00000 0.00000 0.00002kBq/kWhe Ra 0.02011 0.01379 0.00047 0.60120 0.63557kBq/kWhe H3 0.00000 0.00000 0.00000 0.00005 0.00005kBq/kWhe Radionucleides 0.00267 0.00000 0.00000 0.04284 0.04551kBq/kWhe Actinium 0.00170 0.00000 0.00000 0.03708 0.03878Tonnes Chloride 1,726,441 27,147 30,234 22,569 1,806,392Tonnes Sulphate 1,197,108 1,346 18,915 170,875 1,388,243Tonnes Phosphate 10,812 539 7,849 14,189 33,388Tonnes Ammonia 328 41 30 511 911Tonnes Oils- freshwater 34 6 59 3 101Tonnes Oils - seawater 2,174 889 433 81 3,578Tonnes Zinc 2,744 2 37 15 2,798kBq Ra 2,353,497,501 33,284,915 60,468,671 51,139,875,600 53,587,126,686kBq H3 187,303 0 0 4,195,307 4,382,610kBq Radionucleides 312,713,855 0 0 3,644,098,920 3,956,812,775kBq Actinium 198,703,595 0 0 3,154,136,040 3,352,839,63544


In contrast the three industrial gases,hydrofluorocarbons, perfluorocarbons andsulphur hexafluoride, are potent greenhousegases but are only emitted from man madesources. These six greenhouse gasescomprise the ‘basket of emissions’ againstwhich reduction targets were agreed at theThird Conference of the Parties of the UnitedNations Framework Convention on ClimateChange in Kyoto, Japan in December 1997.Carbon dioxide is the major contributor tothe UK’s greenhouse gas emission andarises predominately from the combustion offossil fuels. Non-fossil fuel sources are moredifficult to assess due to the importance ofcarbon dioxide in respiratory processes andits role within the global carbon cycle.Emissions of carbon dioxide from recentlyphotosynthesised carbon sources aretherefore excluded. These include emissionsfrom biomass combustion, the organiccomponent of waste incineration, landfill andsewage treatment are not included.Methane, like carbon dioxide, is naturallyoccurring and is part of the global carboncycle. However the magnitudes of sinks andsources is not well known. Methane in theatmosphere is eventually oxidised to carbondioxide with an estimated lifetime of 12years. The major methane sources are notfrom electricity generation, but rather wastedisposal, agriculture, coal mining and leaksfrom the gas distribution system.Nitrous oxide, the third greenhouse gas isemitted from both natural and anthropogenicsources, namely agriculture, biomassburning, coal combustion and someindustrial processes.Although emission totals are low, it is a verypowerful greenhouse gas and thereforethese emissions have a considerableimpact. The last three gases namelyhydrofluorocarbons, perfluorocarbons andsulphur hexafluoride, have very highgreenhouse warming potential, howeverefforts are being made to phase them out ofusage under the Montreal Protocol.The level of carbon dioxide emissionsassociated with electricity generation isdetermined both by the fuel mix and thegenerating technology used. As naturalgas has replaced coal and oil generationtechnologies this has had a major impact onthe amount of carbon dioxide emitted.This is mostly due to the greater efficiency ofthe combined cycle gas turbine stations(around 50% instead of 34%) and the highercalorific (heating) value of natural gas per unitmass of carbon when compared with coal oroil. An increase in the proportion of nuclearpower generated electricity over the pastdecade has also contributed.Other gases, which are emitted during thecombustion process and have potentiallyadverse effects on the environment,are acidifying gases and these include thesulphur and nitrogen oxides. The depositionof these gases can have adverse effectson buildings and vegetation, as well asacidifying streams and lakes and damagingthe water inhabitants. Sulphur dioxideemissions can be calculated from thesulphur content of the fuel and from thatremaining within the ash itself.Flue gas desulphurisation techniques canalso be employed, and are indeed beingemployed in order to reduce the amount ofsulphur dioxide in the gaseous emissions.For more information please see Chapter 5.The UK National Atmospheric EmissionsInventory (NAEI) estimated in 2001 thatsulphur dioxide emissions had fallen 68%from their 1990 levels, mainly accounted forin power generation by a switch from coaland oil to natural gas, and employment ofclean up technologies.The main source of the nitrogen oxidesis also the combustion processes.However such emissions are much morecomplex since the nitrogen can be derivedfrom both the fuel and atmospheric nitrogen.The emission is dependent on the conditionsof combustion, in particularly temperatureand excess air ratio, which can varyconsiderably.Thus combustion conditions, load and eventhe state of the maintenance programme.Higher levels of NOx arise from intensecombustion and high oxygen availability.These two factors tend to minimise thedifferences that exist between coals 10.4 .The NAEI records that total nitrous oxideemissions have decreased by 36% in theperiod from 1990 to 2001.The other group of gases relates to theamount of ozone present in the troposphereor at ground level. While ozone naturallyoccurs in the atmosphere concentrationscan be increased in-situ by thephotochemical reaction of pollutionprecursors such as carbon monoxide,nitrogen oxides, and volatile organiccompounds (NMVOC - non-methyl volatileorganic compounds or NMHC, non-methylhydrocarbons), together with hydrogenchloride and ammonia.Ozone concentrations can rise significantlyabove background levels particularly in thesummer months when the temperature risesabove 20 o carbon dioxide, there is sunshine,and light winds. The ozone produce canaffect human health and damage cropsand plants.The other main gaseous emission is notreally a gas as such but is emitted in thegaseous stream, so it tends to be includedwith it. This is particulate matter.Historically interest in particulate matterfocused mainly on smoke, which can causehealth problems particularly when incombination with other pollutants.45


The classic example was the London smog’sin the 1950’s and early 1960’s where smokeand sulphur dioxide combinations lead toseveral thousands of deaths being recorded.As the colour of smoke is not a goodindicator of the mass of particles interest hasfocused on the amount of different sizedparticles in the exhaust gases. Focus is onparticles of less than 10µm in size, as theseparticles are the ones most likely to beinhaled into the thoracic region of therespiratory tract. The epidemiologicalevidence on the effects of these particlesshows a good correlation between PM10concentrations and mortality or morbidity.The NAEI records that particulate emissionshave decreased by 39% in the period from1990 to 2001.Finally the figures presented below and inthe mass balance section for the level ofgaseous pollutants are from one particularset of data compiled by ETSU in 1995.They have been calculated from the amountof fuel, whether oil, coal, gas or uraniumwhich was combusted for electricitygeneration in the UK in 2000.In table 10.6, comparison is made for carbondioxide emissions with:1. Those calculated from ETSU data,2. Those measured by the UK government,and published by DEFRA,3. And with the ETSU data corrected bythe NAEI official emission factors(i.e. kgC/tonne fuel) for power stations.In Chapter 11 comparison is made for all themajor gaseous emissions.Table 10-5Gaseous Emissions Produced by the Different Electricity Generation Methods 5Units Gaseous Emission Coal-based Oil-based Gas-based Uranium-based TotalGeneration Generation Generation GenerationLitres water Water (Steam) 0.27020 0.28846 0.16027 0.50007 1.21901(steam)/kWhekg/kWhe CO2 0.93600 0.75510 0.43430 0.00000 2.12540kg/kWhe CO 0.00013 0.00015 0.00007 0.00000 0.00034kg/kWhe CH4 0.00001 0.00001 0.00005 0.00000 0.00007kg/kWhe NMHC 0.00003 0.00003 0.00003 0.00000 0.00009kg/kWhe NOX 0.00423 0.00372 0.00046 0.00000 0.00841kg/kWhe SOX 0.01163 0.01390 0.00000 0.00000 0.02553kg/kWhe PM10 0.00055 0.00040 0.00000 0.00000 0.00095kg/kWhe Benzopyrene 0.00000 0.00000 0.00000 0.00000 0.00000kg/kWhe HCl 474.59332 16.23301 0.28855 1.75320 492.86808kg/kWhe Hg 0.00026 0.00001 0.00000 0.00000 0.00027kBq/kWhe Rn & Ra 57.89760 25.71857 0.00000 1774.80000 1858.41617Litres water Water lost to steam 32,413,718,700 1,614,531,890 23,529,448,227 42,537,565,183 100,095,264,000Tonnes CO2 112,282,560 4,226,295 65,431,935 0 181,940,790Tonnes CO 15,475 817 10,396 0 26,688Tonnes CH4 720 50 7,684 0 8,454Tonnes NMHC 3,119 190 4,821 0 8,130Tonnes NOX 507,431 20,815 69,756 0 598,002Tonnes SOX 1,395,135 77,809 0 0 1,472,944Tonnes PM10 66,218 2,239 0 0 68,457Tonnes Benzopyrene 0 0 42,360 0 42,361Tonnes HCl 56,932,215 90,856 0 149,132 57,172,204Tonnes Hg 31 0 0 0 31Table 10-6Comparative CO2 Data (Emissions (Tonnes)Coal Oil Gas Nuclear TotalETSU a 112,282,560 4,226,295 65,431,935 0 181,940,790DEFRA b 95,121,993 3,580,374 55,431,726 0 154,134,093ETSU / NAEI c 98,540,515 4,162,631 59,483,577 0 162,186,724The main observation that can be madefrom table 10.6 is that the carbon contentassumed for each fuel can have a majorimpact on the amount of CO2 estimated tobe emitted.a. CA Lewis MEET Project: Methodologies for Estimating Air Pollutant Emissionsfrom Transport (ETSU 1995)b. UK Defra, Environmental Protection Statisticsc. National Atmospherics Emissions Inventory available athttp://www.aeat.com/netcen/airqual/naei/annreport/ as of 7th January, 200346


11The core of this report is this chapter’s study on the inputs -outputs and waste streams associated with the various typesof electricity generation.The Electricity GenerationMass BalanceThis chapter presents the data and theassumptions behind the data, for the massbalance on the electricity industry. Some ofthe information in this chapter can be foundin the preceding ones, however, it ispresented here in full for clarity.All the mass balances are presented in2 ways; firstly, in mass (kg) per kWhegenerated or volume (l) per KWhe generatedand secondly, in absolute mass (tonnes) orvolume (litres) per annum.The first mass balance is a composite forthe United Kingdom, and also presents thedata in percentage terms for the four mainelectricity generating methods, namely coal,oil, gas and nuclear. The following massbalances break the information down intoeach of the four generating methods.Finally, suggestion on how the informationcould be used in the other Biffaward massbalances is given.One of the main characteristics of a powerplant, from the technical and economicstandpoints, is its specific consumption,in other words, the amount of heat neededto produce one kWh of electrical energy(KWHe). This specific consumption resultsfrom the thermal cycle balance (table 1).A look at the thermal cycle balance showsthat 4200 kJ must be yielded for each kWhgenerated. In addition, this energy cannot berecovered because its energy is low. Newgeneration systems, especially combinedcycles (or gas-steam turbines), make itpossible to obtain higher efficiencies of evenmore than 55%.11.2 Key Assumptions andReference Data11.2.1 Key AssumptionsThe following are the key assumptionsmade for each of the four main generatingmethods, namely coal, oil, gas and nuclear.11.1 IntroductionThe first table looks at the typical efficiencyof a thermal cycle and highlights the mainreasons for the relatively low efficienciesTable 11-1achieved in the generation of electricity.Example of simplified balance of a thermal cyclefor conventional new designEnergy transformation Energy Efficiency(kJ) (%) (%)Energy from combustion 9000 100.0 100.0Steam generator loss 1050 -11.7 88.3Condenser ‘loss’ 4200 -46.5 41.8Feed water heating -2000 -22.2 (Looping)Turbogenerator losses 65 -0.75 41.05Power supply of auxiliaries 65 -0.75 40.3Loss in main transformer 25 -0.2 40.1Overall efficiency of the facility 40.1The operation of power plants is governedby Carnot’s principle. The heat source,the boiler, provides the energy required forwater vapourisation. The cold source, thecondenser, condenses the steam coming outof the low-pressure turbine.11.2.1a CoalPower station coal - 26 GJ per tonnehome produced plus importsCoal produced119960 GWheEfficiency35% efficiencyMillion tonnes of coal 47.45CompositionCarbon content 67 weight %Hydrogen content 3 weight %Sulphur content 1.4 weight %Oxygen content 8 weight %Nitrogen content 1.4 weight %Chlorine content 0.1 weight %Fluorine content 0.01 weight %Water content 7 weight %11.2.1b NuclearUranium produced 82300 GWheRequiring2595 tonnes UMagnox566.8 tonnes UAGR2391.2 tonnes U3O847


11.2.1c OilPower Station Oil 43.1 GJ per tonneOil produced5597 GWheEfficiency35% efficiencyMillion tonnes of oil 1.34CompositionCarbon 86.30%Hydrogen 11%Sulphur 1.5-3.5%Nitrogen 0.2-0.3%Ash 0.04-0.1%Moisture0.1-1% vol.11.2.1d GasPower Station Gas 49.4 GJ per tonneGas Produced146807 GWheAverage efficiency 46%Million tonnes of gas 23.26Trillion cubic metres 28.87of gasAssume 100% methane (CH4) as the gas is pre-treatedto strip out the other higher order alkanes.11.2.2 Reference DataThe following sources are the mainreferences used in the construction of the mass balance. Additional resources arereferenced in the body of the report.The data upon which the following tables were constructed came from the following sources.CA Lewis MEET Project:Methodologies for Estimating Air Pollutant Emissions from Transport (ETSU 1995)J Bates Full Fuel Cycle Atmospheric Emissions and Global Warming Impacts from UK Electricity Generation (ETSU 1995)Michealis P, Royal Society, Energy Mass Balance, 1991 - used for liquid and solid emissions only -except for phosphate emission (Private communication from C-Tech Innovation)EU Energy Project principally the ExternE Project available at http://externe.jrc.esEIA (US Energy Information Agency) - for gas, coal and oil usage available at http://www.eia.doe.gov/International EnergyAgencyDEFRA - the Department for Environment, Food & Rural Affairs - for water consumption and gaseousemissions comparison available at http://www.defra.gov.uk/UK Energy Sector Indicators from the Department of Trade and Industry available at www.dti.gov.uk/energy/Electricity Association available at http://www.electricity.org.uk/World Nuclear Association for the uranium data, available at http://www.world-nuclear.orgThe amount of oxygen required for complete combustion was adjusted to include other oxygenconsuming elements, for example, nitrogen and sulphur.The air required was calculated as the stoichiometric ratio related to the adjusted carboncontent of the fuel.11.3 The Overall Mass Balance for the United KingdomThe following are the overall mass balances for the UK electricity generation business.Table 11-2The Overall Mass Balance for the U K Generationof ElectricityPer AnnumPer kWheAmount Units Amount UnitsInputsCoal 47,456,703 Tonnes 0.132773 kg/kWheOil 1,335,711 Tonnes 0.003737 kg/kWheGas 23,257,578 Tonnes 0.065069 kg/kWheUranium 567 Tonnes 0.000002 kg/kWheUranium Oxide 2,392 Tonnes 0.000007 kg/kWheAir 1,016,236,760,881 m 3 2843.20 l/kWheWater 11,513,195,000 m 3 32.21 l/kWheC 49,891,481 Tonnes 0.139585 kg/kWheO2 62,867,349 Tonnes 0.175889 kg/kWheOutputsGaseous EmissionsWater lost to steam 100,095,264 m 3 (Water) 0.280044 l/kWheCO2 181,940,790 Tonnes 0.509029 kg/kWheCO 26,688 Tonnes 0.000075 kg/kWheCH4 8,454 Tonnes 0.000024 kg/kWheNMHC 8,130 Tonnes 0.000023 kg/kWheNOX 598,002 Tonnes 0.001673 kg/kWheSOX 1,472,944 Tonnes 0.004121 kg/kWhePM10 68,457 Tonnes 0.000192 kg/kWheBenzopyrene 42,361 Tonnes 0.000119 kg/kWheHCl 57,172,204 Tonnes 0.159955 kg/kWheHg 31 Tonnes 8.67934E-08 kg/kWheRn & Ra 158,059,155,552,083 kBq 442.21 kBq/kWheLiquid EmissionsChloride 1,806,392 Tonnes 0.005054 kg/kWheSulphate 1,388,243 Tonnes 0.003884 kg/kWhePhosphate 33,388 Tonnes 0.000093 kg/kWheAmmonia 911 Tonnes 0.000003 kg/kWheOils- freshwater 101 Tonnes 2.836E-07 kg/kWheOils - seawater 3,578 Tonnes 0.000010 kg/kWheZinc 2,798 Tonnes 0.000008 kg/kWheRa 53,587,126,686 kBq 0.149925 kBq/kWheH3 4,382,610 kBq 0.000012 kBq/kWheRadionucleides 3,956,812,775 kBq 0.011070 kBq/kWheActinium 3,352,839,635 kBq 0.009380 kBq/kWheSolid EmissionsInert waste 57,523,583 Tonnes 0.160938 kg/kWheOther waste 4,999,639 Tonnes 0.013988 kg/kWheRadio active waste 23,286 Tonnes 0.000065 kg/kWheWaste to incinerator 9,554 Tonnes 0.000027 kg/kWheOther waste 32,979 Tonnes 0.000092 kg/kWheAsh 5,694,804 Tonnes 0.015933 kg/kWhePercentage of Total Inputs and Outputsfor each of the Four Main Generating MethodsCoal Oil Gas Nuclear% Electricity Produced 33.56% 1.57% 41.07% 23.80%% Produced Excluding Nuclear 44.04% 2.05% 53.90%InputsAir 95.43% 4.45% 0.12% 0.00%Water 32.38% 1.61% 23.51% 42.50%C 61.38% 2.31% 36.31% 0.00%O2 18.27% 4.89% 76.84% 0.00%OutputsGaseous EmissionsWater lost to steam 32.38% 1.61% 23.51% 42.50%CO2 61.71% 2.32% 35.96% 0.00%CO 57.99% 3.06% 38.95% 0.00%CH4 8.51% 0.60% 90.89% 0.00%NMHC 38.36% 2.34% 59.30% 0.00%NOX 84.85% 3.48% 11.66% 0.00%SOX 94.72% 5.28% 0.00% 0.00%PM10 96.73% 3.27% 0.00% 0.00%Benzopyrene 0.00% 0.00% 100.00% 0.00%HCl 99.58% 0.16% 0.00% 0.26%Hg 99.56% 0.10% 0.00% 0.34%Rn & Ra 4.39% 0.09% 0.00% 95.51%Liquid EmissionsChloride 95.57% 1.50% 1.67% 1.25%Sulphate 86.23% 0.10% 1.36% 12.31%Phosphate 32.38% 1.61% 23.51% 42.50%Ammonia 36.04% 4.47% 3.34% 56.16%Oils- freshwater 33.18% 6.32% 57.75% 2.75%Oils – seawater 60.78% 24.84% 12.11% 2.27%Zinc 98.08% 0.06% 1.34% 0.53%Ra 4.39% 0.06% 0.11% 95.43%H3 4.27% 0.00% 0.00% 95.73%Radionucleides 7.90% 0.00% 0.00% 92.10%Actinium 5.93% 0.00% 0.00% 94.07%Solid EmissionsInert waste 97.40% 0.47% 1.37% 0.76%Other waste 97.24% 0.03% 1.21% 1.53%Radio active waste 75.54% 17.49% 4.61% 2.37%Waste to incinerator 27.11% 67.08% 1.55% 4.26%Other waste 68.89% 26.95% 1.15% 3.01%Ash 100.00% 0.00% 0.00% 0.00%Note: Gaseous emissions have been adjusted to account for the fact thatusing nuclear power creates no gaseous emissions during the generationstage of the fuel cycle.48


The Mass Balance for the UK Generation of Electricity using CoalPer AnnumPer kWheAmount Units Amount UnitsInputsCoal 47,456,703 Tonnes 0.395604 kg/kWheAir 969,760,742,843,562 Litres 2494.47 l/kWheWater 3,728,302,910,213 Litres 31.86 l/kWheC 30,622,516 Tonnes 0.680727 kg/kWheO2 11,483,444 Tonnes 0.255273 kg/kWheOutputsGaseous EmissionsWater lost to steam 32,413,718,700 Litres (Water) 0.270204 l/kWheCO2 112,282,560 Tonnes 0.936000 kg/kWheCO 15,475 Tonnes 0.000129 kg/kWheCH4 720 Tonnes 0.000006 kg/kWheNMHC 3,119 Tonnes 0.000026 kg/kWheNOX 507,431 Tonnes 0.004230 kg/kWheSOX 1,395,135 Tonnes 0.011630 kg/kWhePM10 66,218 Tonnes 0.000552 kg/kWheBenzopyrene 0 Tonnes 6.79E-07 kg/kWheHCl 56,932,215 Tonnes 474.59 kg/kWheHg 31 Tonnes 0.000257 kg/kWheRn & Ra 6,945,396,315,639 kBq 57.90 kBq/kWheLiquid EmissionsChloride 1,726,441 Tonnes 0.014753 kg/kWheSulphate 1,197,108 Tonnes 0.010230 kg/kWhePhosphate 10,812 Tonnes 0.000092 kg/kWheAmmonia 328 Tonnes 0.000003 kg/kWheOils- freshwater 34 Tonnes 2.87E-07 kg/kWheOils - seawater 2,174 Tonnes 0.000019 kg/kWheZinc 2,744 Tonnes 0.000023 kg/kWheRa 2,353,497,501 kBq 0.020111 kBq/kWheH3 187,303 kBq 0.000002 kBq/kWheRadionucleides 312,713,855 kBq 0.002672 kBq/kWheActinium 198,703,595 kBq 0.001698 kBq/kWheSolid EmissionsInert waste 56,027,899 Tonnes 0.478769 kg/kWheOther waste 4,861,723 Tonnes 0.041544 kg/kWheRadio active waste 17,590 Tonnes 0.000150 kg/kWheWaste to incinerator 2,590 Tonnes 0.000022 kg/kWheOther waste 22,721 Tonnes 0.000194 kg/kWheAsh 5,694,804 Tonnes 0.016615 kg/kWheThe Mass Balance for the UK Generation of Electricity using OilPer AnnumPer kWheAmount Units Amount UnitsInputsOil 1,335,711 Tonnes 0.238648 kg/kWheAir 45,246,339,427,271 Litres 2025.03 l/kWheWater 185,707,292,602 Litres 76.93 l/kWheC 1,152,626 Tonnes 0.205936 kg/kWheO2 3,073,669 Tonnes 0.549164 kg/kWheOutputsGaseous EmissionsWater lost to steam 1,614,531,890 Litres (Water) 0.288464 l/kWheCO2 4,226,295 Tonnes 0.755100 kg/kWheCO 817 Tonnes 0.000146 kg/kWheCH4 50 Tonnes 0.000009 kg/kWheNMHC 190 Tonnes 0.000034 kg/kWheNOX 20,815 Tonnes 0.003719 kg/kWheSOX 77,809 Tonnes 0.013902 kg/kWhePM10 2,239 Tonnes 0.000400 kg/kWheBenzopyrene 0 Tonnes 5.33E-07 kg/kWheHCl 90,856 Tonnes 16.23 kg/kWheHg 0 Tonnes 0.000006 kg/kWheRn & Ra 143,946,836,444 kBq 25.72 kBq/kWheLiquid EmissionsChloride 27,147 Tonnes 0.011246 kg/kWheSulphate 1,346 Tonnes 0.000557 kg/kWhePhosphate 539 Tonnes 0.000223 kg/kWheAmmonia 41 Tonnes 0.000017 kg/kWheOils- freshwater 6 Tonnes 0.000003 kg/kWheOils - seawater 889 Tonnes 0.000368 kg/kWheZinc 2 Tonnes 0.000001 kg/kWheRa 33,284,915 kBq 0.013788 kBq/kWheH3 0 kBq 0 kBq/kWheRadionucleides 0 kBq 0 kBq/kWheActinium 0 kBq 0 kBq/kWheSolid EmissionsInert waste 271,473 Tonnes 0.112458 kg/kWheOther waste 1,346 Tonnes 0.000557 kg/kWheRadio active waste 4,072 Tonnes 0.001687 kg/kWheWaste to incinerator 6,409 Tonnes 0.002655 kg/kWheOther waste 8,888 Tonnes 0.003682 kg/kWheAsh 0 Tonnes 0 kg/kWheThe Mass Balance for the UK Generation of Electricity using Natural GasPer AnnumPer kWheAmount Units Amount UnitsInputsGas 23,257,578 Tonnes 0.158423 kg/kWheAir 1,229,678,610,499 Litres 3564.54 l/kWheWater 2,706,413,019,478 Litres 20.89 l/kWheC 18,116,339 Tonnes 0.129726 kg/kWheO2 48,310,236 Tonnes 0.345936 kg/kWheOutputsGaseous EmissionsWater (Steam) 23,529,448,227 Litres (Water) 0.160275 l/kWheCO2 65,431,935 Tonnes 0.434300 kg/kWheCO 10,396 Tonnes 0.000069 kg/kWheCH4 7,684 Tonnes 0.000051 kg/kWheNMHC 4,821 Tonnes 0.000032 kg/kWheNOX 69,756 Tonnes 0.000463 kg/kWheSOX 0 Tonnes 0 kg/kWhePM10 0 Tonnes 0 kg/kWheBenzopyrene 42,360 Tonnes 4.828E-07 kg/kWheHCl 0 Tonnes 0.288545 kg/kWheHg 0 Tonnes 9.783E-07 kg/kWheRn & Ra 0 kBq 0 kBq/kWheLiquid EmissionsChloride 30,234 Tonnes 0.000233 kg/kWheSulphate 18,915 Tonnes 0.000146 kg/kWhePhosphate 7,849 Tonnes 0.000061 kg/kWheAmmonia 30 Tonnes 2.345E-07 kg/kWheOils - freshwater 59 Tonnes 4.518E-07 kg/kWheOils – seawater 433 Tonnes 0.000003 kg/kWheZinc 37 Tonnes 2.885E-07 kg/kWheRa 60,468,671 kBq 0.000467 kBq/kWheH3 0 kBq 0 kBq/kWheRadionucleides 0 kBq 0 kBq/kWheActinium 0 kBq 0 kBq/kWheSolid EmissionsInert waste 789,369 Tonnes 0.006093 kg/kWheOther waste 60,320 Tonnes 0.000466 kg/kWheRadio active waste 1,072 Tonnes 0.000008 kg/kWheWaste to incinerator 148 Tonnes 0.000001 kg/kWheOther waste 378 Tonnes 0.000003 kg/kWheAsh 0 Tonnes 0 kg/kWheThe Mass Balance for the UK Generation of Electricity using UraniumPer AnnumPer kWheAmount Units Amount UnitsInputsUranium 567 Tonnes 0.000032 kg/kWheUranium Oxide 2,392 Tonnes 0.000037 kg/kWheAir 0 Litres 0 l/kWheWater 4,892,771,777,707 Litres 57.52 l/kWheC 0 Tonnes 0 kg/kWheO2 0 Tonnes 0 kg/kWheOutputsGaseous EmissionsWater lost to steam 42,537,565,183 Litres (Water) 0.5000713 l/kWheCO2 0 Tonnes 0 kg/kWheCO 0 Tonnes 0 kg/kWheCH4 0 Tonnes 0 kg/kWheNMHC 0 Tonnes 0 kg/kWheNOX 0 Tonnes 0 kg/kWheSOX 0 Tonnes 0 kg/kWhePM10 0 Tonnes 0 kg/kWheBenzopyrene 0 Tonnes 5.436E-08 kg/kWheHCl 149,132 Tonnes 1.753200 kg/kWheHg 0 Tonnes 1.224E-06 kg/kWheRn & Ra 150,969,812,400,000 kBq 1774.80 kBq/kWheLiquid EmissionsChloride 22,569 Tonnes 0.000265 kg/kWheSulphate 170,875 Tonnes 0.002009 kg/kWhePhosphate 14,189 Tonnes 0.000167 kg/kWheAmmonia 511 Tonnes 0.000006 kg/kWheOils - freshwater 3 Tonnes 0.000000 kg/kWheOils - seawater 81 Tonnes 9.54E-07 kg/kWheZinc 15 Tonnes 1.732E-07 kg/kWheRa 51,139,875,600 kBq 0.601200 kBq/kWheH3 4,195,307 kBq 0.000049 kBq/kWheRadionucleides 3,644,098,920 kBq 0.042840 kBq/kWheActinium 3,154,136,040 kBq 0.037080 kBq/kWheSolid EmissionsInert waste 434,842 Tonnes 0.005112 kg/kWheOther waste 76,250 Tonnes 0.000896 kg/kWheRadio active waste 551 Tonnes 0.000006 kg/kWheWaste to incinerator 407 Tonnes 0.000005 kg/kWheOther waste 992 Tonnes 0.000012 kg/kWheAsh 0 Tonnes 0 kg/kWhe49


11.8 DefinitionsAir emissionsCO2kgMethane (CH4)kgCarbon dioxide associated processeswith combustionMethane emissions11.3 Using the Overall ElectricityGeneration Mass BalanceThe data presented in this section of the report has been designed tofulfil two criteria, namely:1. Provide information on the total annual inputs and outputs forthe electricity generation industry.SOx Emissions of SO2, SO 3, - SO 2- 4kgNOxkgNMVOCkgEmissions of all oxides of nitrogenNon-methane volatile organic compoundsEmissions of organic compounds otherthan methaneHydrogen chloride Emissions to air of hydrogen chloridekgMercurykgRadionucleideskBqEmissions of mercuryEmission of radionucleides in termsof their activity (1kBq = 1000 decays/second)2. Provide information on the mass (or volume) per kWhe(kilowatt-hour of electricity generated).It is the second set of information which is focused on the use of thedata gathered for this report by the other Biffaward Mass BalanceStudies, which have been published, or in preparation. In thesestudies the electricity consumption has been noted as kWh per unit,the information in this report can now quantify inputs and emissionsfor each kWh.Although the information presented here is detailed, on, for example,gaseous emissions associated with each kWhe, the author wouldsuggest the consideration of the three main greenhouse effect causingemissions, namely, carbon dioxide, methane and nitrous oxide.Noble gaseskBqAerosolskBqActinideskBqEmission of noble gases in terms oftheir activityEmission of aerosols in terms of their activityEmission of actinides in terms of their activityWater emissionsChloridekgSulphatekgAmmoniakgPhosphatekgOils-freshwaterkgOils-seawaterkgRadionucleideskBqEmission to water of chloride ionsEmission to water of sulphate ionsEmission of ammonia to waterEmission of phosphates to waterEmission of oils to freshwater bodiesEmission of oils to seawater bodiesRadioactivity of substances emitted to waterSolid EmissionsInert wastekgOther wastekgMass of chemically inert wasteMass of non-inert wasteRadioactive waste Mass of radioactive wastekg50


12Thischapter examines the current status of the renewablemarket in the UK, and comparisons are made with the worldwide situation where relevant. An outline of the different,relevant technologies is made, followed by an assessment ofthe current market position and pertinent legislation.The Use ofEmerging Technologiesfor Renewable EnergyFigure 12-1CHP Performance byMain Prime MoverOperating Hours (‘000)6543210Steam Gas Combined ReciprocatingTurbine Turbine Cyle Gas EngineTurbineTypical Operating Hours per AnnumOverall Efficiency (%GCV)Figure 12-2Types of Fuel Used byCHP Schemes in 2001natural gas 60%fuel gas 7%coal 7%renewables 2%other fuels 24%-75%-74%-73%-72%-71%-70%-69%-68%-67%-66%12.1Combined Heat and Power (CHP) 12.1.3 Current StatusIn the last ten years capacity has more12.1.1 Introductionthan doubled for CHP, and the averageCHP is the simultaneous generation ofgrowth rate has been 8% per annum.usable heat and power (usually electric) in aApproximately 6% of electricity generatedsingle process. CHP uses a variety of fuelsin the UK was produced by CHP in 2001.and there are many different sizes of engineThe main user of this electricity is theand places it is used. There are 4 main typesindustrial sector, with 91% of the capacity.of CHP scheme: steam turbine, gas turbine,The remaining 9% is used in the commercial,combined cycle systems andpublic and residential sectors.reciprocating engines. CHP plants tendto be much smaller than conventionalpower plants and are connectedto the lower voltagedistribution system.CHP generation doesn’tsuffer from transmissionand distribution losses,and can provideimportant networkservices such as black start,improvements to powerquality and the ability to workalone if the grid goes down.There are several types ofengine used in CHP, each withtheir own efficiency and averageoperating hours.12.1.2 Fuel UseTWHFigure 12-3Number and Capacity of CHP schemes by sector500-350450-300400350-250300-200250-150200150-100100-50500-0LeisureHotelHealthResidentialUniversitiesOfficesThe main fuel used by CHP systems isThe majority of schemes in the above chartnatural gas. The percentage of coal useare based on spark ignition reciprocatinghas increased over the last year and gasengines fuelled with natural gas.decreased, due to a raise in gas pricesin 2001. Other fuels, for example12.1.4 Government and Economicsrenewables, waste products etc.The Government has set a target ofaccount for approximately a quarter of achieving at least 10,000 MWe of Goodfuel use in CHP. Because of theQuality CHP capacity by 2010. This is toprocess of combustion used for these help reduce carbon emissions and deliverfuels, the overall efficiency when using the UK’s Climate Change Program.them will always be lower, yet there Like most alternative generationare many environmental benefitstechnologies, the main obstacle facingto consider. The Fig 12.2 shows the CHP is the cost of the electricity produced.proportion of fuels used in CHP in the The cost of the fuel is also a problem.UK in 2001:The total generation capacity in the UK isabove demand so there is little effort toinvest in new CHP capacity.Thermal & Electrical Capacity (MW)51


The graph below shows how heat andelectrical generation from CHP in the UK haschanged over the last five years:Figure 12-4Recent Generation Developmentsof CHP in the UKAnnual UK Generation (‘000)7060504030201001997 1998 1999 2000 2001Electricity GenerationHeat Generation12.1.5 Non-domestic CHP (mini-CHP)Conventional CHP is currently viable in nichesegments in sizes down to perhaps 30 kWe,limited mainly by maintenance costs.New technologies claim to have significantincreases in availability, reliability andreduced maintenance requirements.The main technology used isthe internal combustion engine(ICE). They typically requireservicing every 600 hours.Fuel cells, micro-turbines,and Stirling engines havefewer moving parts than theICE, therefore reliability andavailability are better andservice cost is reduced.Mini-CHP could grow significantlyin Europe’s electrical systemwithin the next few years.Tightening greenhouse gas emissionlimits and widening market competitionare helping this to occur.12.1.6 MaintenanceMaintenance makes a significant contributionto the running of mini-CHP systems,particularly on smaller units. Five-yearrolling maintenance contracts are offered forsome emerging mini-CHP technologiesguaranteeing 95% availability at £2500 peryear for a 45kWe unit operating for 6000h.Table 12-1Comparison of Purchase and OperationalCosts for Certain Emerging TechnologiesAs can be seen, the amount of heat andelectricity generated by CHP has remainedrelatively constant over the last five years.The Government is doing several things tohelp reach the 10,000 MWe target previouslymentioned, including:- Climate Change Levy exemption on fuelinputs to Good Quality CHP- Business Rates exemption for CHPpower generation plant and machinery.- A reduction in VAT on certaingrant-funded domesticmicro-CHP installations.Stirling Fuel Cell Micro IC Engines(PEM) Turbine Trad. NewSize (kWe) 10 1 - 200 30 - 200 30 - 200 1 - 10Cost(g/kWe)1000 4000 750 - 1000 1000 2400Efficiency 20% 30 - 45% 15 - 30% 25 - 30% 25%ReliabilityVeryGoodFair Excellent GoodVeryGoodServiceCost 1.2 2 1.2 2.5 1.5(g/kWh)GenerationCost 4 5 4 6 5(g/kWh)- The launch of the £50m CommunityEnergy Programme to encourageCHP use in the community plusother measures.By modelling various energy price scenarios,Cambridge Econometrics suggests thatcapacity will reach 9,300 - 10,300 MWe by2010 under measures currently in place andrecently announced.Figure 12-5A Typical CHP Plant52


12.1.7 Residential CHP (Micro-CHP)Micro-CHP is different from conventionalCHP in that it is used in the highly changingelectrical loads in individual homes.Therefore the power cannot always beprovided from the micro-CHP unit, and thehouse must be connected to a grid. A varietyof technologies exist to implementmicro-CHP, including Stirling engines,fuel cells, thermo-electric effect, thermophotovoltaiceffect and long-life IC engines.Of these, only Stirling engines and fuel cellsappear to be at a realistic demonstrationstage for the residential market.Thermally, micro-CHP is likely to be asefficient, or better, than conventional heatingsystems. Initial assessments of micro-CHPunits, suggest that they will be a highly costeffective solution for residential propertiesthat cannot be insulated further (to reducethermal demand), and will be more costeffective than most lighting and applianceenergy efficiency measures.12.1.8 Prospects12.1.8.1 Mini-CHPWith government support, cheap gas andno major administrative barriers, prospectsfor mini-CHP appear to be good.Gas central heating, or air conditioning withgas heating, are the most popular systemsin most buildings and these are well suitedto replacement with mini-CHP systems.However, sales and progress may behindered by a lack of willingness to lookinto and use new technologies. The bestprospects may lie with innovative ESCoswho can turn mini-CHP into a profitablebusiness within the privatised energymarkets.Table 12-212.1.8.2 Micro-CHPThe significant heating load, very largepotential market and pump priming subsidyof 5% VAT indicate that the UK should havean excellent market for micro-CHP. This issomewhat counteracted by the low price ofelectricity. The spread of heating demandsuggests that around 50% of gas heatedhomes will have heating demands largeenough to support a micro-CHP unit.An estimate is that the likely potential marketis around 20 million homes, about most ofwhich could operate on gas. Therefore it isexpected that units will be generally availablein 2003-4 with sales of up to 300,000 unitsper annum by 2010.12.2 Fuel Cells12.2.1 IntroductionIn the last decade there has been a big effortto develop fuel cells. The concerns aboutemissions and environmental issues with thedesire for greater electrical efficiency haveled to large research and developmentprojects being initiated by manygovernments. There has also been a veryrapid growth in the amount of industrialinvestment, as the commercial prospects forfuel cells have become clearer.There are four main components that a fuelcell power plant consists of: the stack,the fuel reformer, the power electronics andthe balance of plant.12.2.2 Typical Fuel Cell Stack -TechnologyThere are several types of fuel cell, eachhaving a different stack with its owncharacteristics (see Table 12-2):Figure 12-6Typical Fuel Cell Stacks12.2.3 Advantages of Fuel CellsThe main advantages of fuel cells are theirhigh electrical efficiency and very lowemissions. They also have the ability tochange their output to suit demand, whichcan allow the efficiency to be raised further.Electrical efficiencyFuel cells have electrical efficiencies rangingfrom 35% to around 50%, with the potentialfor up to 70% for larger systems. This isthe highest of all plant considered, and isgenerally higher than the current, overallnetwork efficiency in the UK at around 36%.This can be a very attractive feature forpremises or processes with low heat topower ratios, which have previously beenunable to find a suitable CHP plant to suit.Status and Comments on the Different Fuel Cells AvailableStatusCommentsSolid oxide fuel cells Tubular and planar technology under development. Best suited for large-scale stationary power generators,(SOFC)and smaller continuous systems. High electrical efficiency.Molten carbonate 250kW-1MW systems being demonstrated. Suited for larger stationary power generatorsfuel cell (MCFC)Phosphoric acid 200kW system offered for sale, but not Most developed of fuel cells, with over 200 demonstrationsfuel cell (PAFC). commercially competitive in the UK. of this technology. Used in stationary power generation.Alkaline fuel cell Highly developed for space systems Low temperature fuel cells. Contain no platinum in the(AFC) and suitable for some smaller applications. cell stack, which gives a competitive advantage overPEMs. Susceptible to contamination. Very expensive.Proton exchange 250kW CHP, residential CHP, cars and buses One of the most promising technologies. Potential formembrane fuel cell being demonstrated but not yet commercially viable. rugged low cost units.(PEMFC)53


Fuel cells also look highly attractive for cars ifproduction costs can be lowered to around$30-$50/kW:Figure 12-7Comparison of Efficiency ofDifferent Powered Cars12.2.4 ApplicationsResidential Power GenerationTable 12-3 shows the applications of several This system has the potential to produce updifferent fuel cells:to seven kilowatts of power, and requires agas or propane reformer. A large amount ofTable 12-3heat is also produced, and this can be usedApplications of Fuel Cellsto heat the house and water.Power Generation8070PEMCommercial Residential CHP Space Transport PortableX X X X60PAFCX X X% Efficient402010MCFCSOFCX X XXX0AFCXXHydrogen Fuel Cell Gasoline BatteryDMFCXBenefitsOther than efficiency, fuel cells havesignificant environmental advantages inthat they have very low emission levels ofpollutants such as nitrogen or sulphuroxides. This means that fuel cells don’tcontribute to smog or acid rain like othertechnologies. A large percentage of heatproduced by fuel cells can be captured andreused, instead of being released into the air.Unlike most generation technologies fuelcells have no moving parts and are quiet inoperation. They never need to be rechargedor replaced and will work continuously ifsupplied with hydrogen or another fuel.ProblemsBecause fuel cells use hydrogen, thispresents several problems. Hydrogen hassome limitations that make it impractical foruse in most applications. It is difficult tostore and distribute. Using a device called areformer, other fuels such as natural gas andgasoline can be converted to producehydrogen. It should be noted that reformersgenerate heat, produce other gases besideshydrogen and reduce efficiency.AutomobilesA fuel cell car is very similar to a battery carbut with a fuel cell (and reformer if required)instead of a battery. Methanol, gasoline, andhydrogen are all potential fuels.Figure 12-8An Example of a Fuel Cell CarPortable PowerFuel cells are already being used in laptops,mobile phones and could even be used inhearing aids. They have an advantage overbatteries in that they have a much longer life,and can be recharged quicker with fuel.BusesFuel cell buses are already operational in afew countries. Numerous fuel cell buses arealready on trial across America and Europe.Hundreds of systems are already on trialworldwide.Large Power GenerationFuel cells are more efficient thanconventional power plants. The heatgenerated by the fuel stack can alsobe used. Fuel cell plants are quieter,and produce fewer pollutants thanconventional fossil fuel plants. One 200kWeplant has been on commercial sale nowfor over 10 years with over 200 unitssold worldwide.12.2.5 The Fuel Cell MarketInitial market entry is widely expected to bein areas that can stand a higher cost perkWh of energy, such as portable applicationsand battery replacement. Early markets areprobably going to be in North America.The bus industry is expected to be a majorfuel cell application, as the requirements areless demanding than the car industry andrefuelling and maintenance are easier toimplement. Cars have the potential for ahuge fuel cell market, but cost is holdingthis technology back. Most automobilemanufacturers have R&D schemes in place,and are forecasting initial sales around 2004,with significant sales around 2010.The potential of distributed power generationand CHP for fuel cell technology isn’t asgood as for cars or buses, yet the demandsrequired for the technology are easier tomeet. Sales in the distribution power sectorhave already begun. The stationary heat andpower markets for fuel cells are expected togrow by around £1.9billion per year by 2020.54


Prospects for the UKThere is a growing interest in fuel cells inthe UK, and it is believed they could make acontribution to energy production in thefuture. The UK has green house gascommitments and the use of fuel cellscould allow these to be met, although theircontribution would probably come into affectaround 2010. Like most new technologiesdemonstration and operating experience arevital, but government support is needed.Fuel cells are a rapid growth industry andone that is unlikely to slow, but the problemlies in that there are a commercial andfinancial risks in fuel cells, and UK industryneeds assistance before it invests in thistechnology. The graph below shows thepredicted value, from EnvironmentalBusiness International, of the global fuel cellmarket over the next decade:12.3.2 Power PlantGas turbines are now becomingcommercially available in packagedgeneration only and mini-CHP units in the20-200 kWe range. Competing units havebeen developed from aircraft auxiliary powerunits (APUs) and turbo-compressors.High rotational speed and compactness arefeatures of these two units, and they aremore suited to industry. The micro-turbinemarket stands to benefit from the improvedefficiency of units, derived from using highfrequency permanent-magnet alternatorsmounted directly to the rotor shaft (that alsodouble as starter-motor), where output isconverted to mains frequency and voltage bymodern power electronics. Along with fuelcells, it is looking increasingly likely thistechnology may compete with IC enginesin the transport sector in the long-term.Table 12-4 shows how the micro-turbine12.3.3 CostsCapital costs are currently similar to those ofconventional reciprocating engines at ~e750/kWe - e1000/kWe for a micro-turbine,but if production rises, these prices may fall.Maintenance costs, although low comparedto reciprocating IC engines, are still a largeproportion of running costs.Manufacturers CostPricing of micro-turbines has specificeconomics for viability. Capstone’s Model330 (30 kWe) has a list price of around$27,000 ($900 per kWe). In 2001, theHoneywell model had a price of $800 -$825/kWe and the Turbec unit is pricedbetween $650 and $700 per kWe.Complete CHP systems such as BowmanPower Systems are targeted to beapproximately $750-$800 per kWe.compares to other technologies:Figure 12-9Predicted Global Fuel Cell Market Table 12-4Comparison of Micro-turbines and Other Technologies1210Stirlingengine(Solo)Fuel CellPEM)Micro-Turbine(Capstone)TraditionalIC EnginesNew$ Billion864202000 2000 2010Size (kWh)CurrentCapital Costcg/kWeFuelSteamRaisingAbility101000Liquid/Gas/SolidNo1-2004000H2,NGMethanolYes30-200750-1000Liquid/GasYes30-2001000Liquid/GasSome1-102,400Liquid/GasNo12.3 Micro-turbinesEfficiency(HCV)20%30-45%10-30%25-30%25%12.3.1 IntroductionMicro-turbines have a long history asautomotive power units. Today, withimproved high-temperature turbine bladematerials allied to high-frequency solid-stateelectronic drives, the gas turbine ischallenging the reciprocating InternalCombustion engine market. Modern microturbinesgenerally have just one moving part,the rotor/compressor assembly, with twobearings. This offers advantages ofcompactness, reliability, low weight, lowemissions and low maintenance. The highexhaust temperature in gas turbines can beutilised to raise process steam or feed anabsorption chiller for refrigeration andair-conditioning duties, effectively providingCombined Heat, Power and Cooling (CHPC).Noise (dBA)NOx(mg/kWh)ReliabilityService Life(h)Service Cost(cg/kWh)Overhaul(h)Life (h)PowerDensity(kW/m 3 )70@1m100VeryGood5,0001.220,00080,0001065@1m10Fair5,0002.040,00050,0002.575@1m150VeryGood5,0001.250,000100,0002590@10m1000VeryGood1,0002.55,00050,0002055@1m1000VeryGood3,5001.58,00080,00020GenerationCost(cg/kWh)4546555


Figure 12-10The Turbec Micro-Turbine12.3.4 Advantages of Micro-turbinesMicro-turbines require low maintenance,have a long life, are relatively cheap,compact, and reliable and can have variableoutput and recuperation (using heat in theexhaust to pre-heat the compressed air priorto combustion). These can be summarisedas follows:Low maintenance:Micro-turbines require significantly lessmaintenance than traditional IC engines ofa similar size.Long life:As there is generally only one moving partwithin the unit, a long life can be expecteddue to the reliability of that part.The main rotor should last at least 40,000hours before replacement is required,and sometimes longer.Low unit costs:The units are generally cost competitivewith IC engines on capital cost alone.This provides a competitive advantage whenmaintenance costs are included.Variable output and recuperation:The output can be modulated to someextent without a large loss in efficiency.Recuperation can also be modulated tohelp match the thermal load.12.3.5 Disadvantages ofMicro-turbinesThe units can be quite noisy (70 - 80 dBA)and generally are designed to run once perday. They are not designed for repeatedstop / starts.Micro-turbines tend to be limited to particularmarket sections where they offer distinctoperational advantages. The heat to powerratio of the plant determines the typicalapplication, so it can be concluded thatdifferent types of plant may be more suitablefor specific countries. Micro-turbines (with aheat to power ratio of approximately 2:1 to5:1) would also be more suitable in countrieswith a large difference between electricityand gas prices. However, as the ratio rises,electricity price becomes less important.12.3.6 EfficiencyBasic efficiencies of ~15% are typicallyachieved but this can be improvedsignificantly by using some of the heatavailable in the exhaust to pre-heat thecompressed air prior to combustion(recuperation). However, without animprovement in heat exchanger performance,this can be at the expense of overallefficiency in CHP applications.Some micro-turbine CHP systems are ableto vary the amount of recuperation to boostthermal output as required. Micro-turbinescan also give a range of power outputdependent upon the level of recuperation,i.e. more recuperation gives greater electricalefficiency (more kWe); less recuperationgives lower electrical efficiency and higherheat output. The graph below shows howefficiency can vary with recuperation:As can be seen in figure 12-11, the overallefficiency is greater in the simple cyclemicro-turbine, but the electrical conversionefficiency is less. The following graph showsthe power input and thermal output for thesame Micro-turbine:Table 12-5 shows the simple cyclemicro-turbine has a greater heat input and agreater thermal output.CompanyBowmanPowerSystems LtdCapstoneTurbineCorp.Ingersoll RandEnergySystemsThe TurboGensetCompanyLtdTurbec ABElliot EnergySystemsModelTG 35TG 80Micro Turbine330PowerworksTG 50T 100TA 80Net Elec.Output (kWe)32.9803030-25045105( +/- 3)80% EfficientkWFigure 12-11Performance of a Micro-Turbinewith/without Recuperation9080706050403020100450400350300250200150100Net Thermaloutput(kWh)-150-420---167( +/- 5)-500Simple CycleSimple CycleOverall EfficiencyFigure 12-12Performance of a Micro-Turbinewith/without Recuperation(Electrical Conversion)Overall EfficiencyTable 12-5Properties of Leading Micro-turbinesFuelsNatural GasNat. Gas/LPGPropane/ButaneNat. Gas/LPGPropane/DieselNat. Gas/OthersDiesel, KeroseneNat. GasNat. Gas-OverallEfficiency6374-8624-28(LHV)8090(Net. Elec.Conv.Eff.)7880NoiseLevel-77dBA@1m65dBA@10m


12.3.7 Potential MarketsCurrently, most solar cells use multicrystallineBelow is a list of the potential marketssilicon. This technology has undergone amicro-turbine technology could enter:major effort by governments to increase its- On-site CHPuse and development, but high prices for thecells mean it is not as commercially viable as- Uninterruptible Power Suppliesother renewable sources and therefore has- Distributed Power Generationa niche market. Developments in this- Auxiliary Power Units for vehiclestechnology are looking to lower costs and- Portable Generationhelp integrate solar energy generationtechniques into the major grids.- Hybrid Electric Vehicles- Transport & Remote Generation12.4.2 Current StatusThe capacity of solar generation hasIn particular, new technologies such asrisen every year in the UK and stoodmicro-turbines are capable of providingat 2.75 MW in 2001. Developmentsrelatively high-grade waste heat, well above in this technology are looking to lowerthe 120 o C ceiling produced by conventional costs and help integrate solar energylow temperature technologies.generation techniques into theResearch has shown that there is scope tomajor grids.use such a technology in tandem withabsorption cooling facilities. Such anapplication could be particularly useful in thefood retail and manufacturing sectors.Current ProductsFigure 12-13Declared Net Capacity ofSolar Generation in UKMicro-turbine packages including absorptionchillers are being developed for CHP andchilling applications. The main micro-turbineproducts are:Capstone’s, Model 330Bowman Power Systems Turbogenfamily, TG45, TG60, TG80Ingersoll Rand Energy Systems,PowerworksTurbec’s, T100Table 12-5 shows the characteristicsof these and other models (figures fromcompany websites, correct at 10/02/2002):12.4 Solar Cells12.4.1 IntroductionSolar cells are mainly placed on the roofs ofhomes, apartments, low rise offices, smallshops, schools, government buildings, barnsand garages. They allow people to obtainthe benefits of making their own electricitywhilst having the knowledge they are stillconnected to, and have the backup of,a major grid. Solar cells could in the futureplay a useful role by taking the demand offother equipment and therefore prolongingits life span. For example, solar cellscould be used to extend the life ofoverload transmission circuits anddelay the need for capacity increases.Thousand Tonnes of Oil EquivalentMWe32.521.510.501996 1997 1998 1999 2000 2001The following DTI statistics show theincrease in quantity of electricityproduced by photovoltaics over the pasteleven years:Figure 12-14Quantity of Electricity Producedby Photovoltaics in the UK1614121086420TWHPresently, there are many different materialsthat solar cells can be made from. These alldiffer in price.6005004003002001000Figure 12-15Quantity of Electricity Producedby Photovoltaics in the UKSingle-CrystalSiliconWithConcentratorPolycristallineSiliconAmorphousSiliconCopper IndiumDiselenidePotentialThin FilmThe latest solar cells are getting close tobringing the cost levels to an acceptablefigure, and current crystalline cells can bebuilt for manufacturing costs of $3.50 to$4 per watt generated. Many peopledeveloping these cells expect newerthinner films to do even better; statingthat newer devices could producepower for less than $0.50 per watt.Table 12-6Comparison of PhotovoltaicCell CharacteristicsCell Theoretical Lab CommercialMaterial Efficiency Efficiency Efficiency(%) (%) (%)Single-Crystal 30 23.5 12 to 14SiliconWith 37 28.2 13 to 15ConcentratorPolycrystalline 25 17.8 11 to 13SiliconAmorphous 17 13 4 to 6SiliconPolycrystalline 27 15.8 6Thin FilmsCopper Indium 19 16.4 11DiselenideGallium 28 27.6 -ArsenideWith 39 29.2 -ConcentratorAs can be seen from the table above,gallium arsenide with concentrator isthe most efficient material,with amorphous silicon being theworst of those that are beingconsidered.571990 1999 2000 2001


Global MWe Installed12.4.3 TechnologiesCrystalline Silicon is the leading commercialmaterial for photovoltaic cells, and is used inseveral forms.Figure 12-16Materials Used in Solar Cells10090807060504030201001997 1998 1999Thin FilmThin film photovoltaic cells use layers ofsemiconductor materials only micrometersthick attached to an inexpensive backingsuch as glass, flexible plastic or stainlesssteel. The cost of manufacturing thin films isa lot less than standard PV cells due to thesmall amount of semiconductor materialrequired.Single CrystalGroup III-V Photovoltaic (based on Group IIIand V elements in the periodic table)technologies have high conversion ratios ofsunlight to electricity under either normalsunlight or sunlight that is concentrated.These single crystal cells are normally madefrom gallium arsenideHigh-Efficiency Multi-junction DevicesMulti-junction devices stack individual solarcells on top of each other to maximise thecapture and conversion of solar energy.The top layer captures the highest-energylight and passes the rest on to be absorbedby the lower layers. Much of this area usesgallium arsenide.Advanced Solar CellsA variety of advanced approaches to solarcells are under investigation. Dye-sensitisedsolar cells use a dye-impregnated layer oftitanium dioxide to generate a voltage, ratherthan semiconducting materials used in mostsolar cells. This technology is cheap andtherefore has the potential for lower cost.12.4.4 ProblemsThe main problem facing this technology iscost. As with most renewable plant, thesource is not as reliable as fossil fuels andthis means a storage system may have tobe integrated. Also, the safety of thecells is a concern when used inpublic areas, as they onlywitch off with the absence250of sunlight.To overcome theseproblems researchneeds to be done onnew materials, and likewind production,the normalisation of designwould help lower costsand problems.Additional ProblemsAn installed PV system requires balance ofplant (BoP) technologies, for example,inverters, electrical switches andwiring, mounting structures etc.On average, these systems makeup half the final cost of the PVsystem. The BoP technologiesare not normally made by themanufacturers of the PV cells,meaning the PV industry has littleto do with the cost of the BoP.12.4.5 Forecast - GrowthThe rate of market growth in the PVindustry will depend on discussionsacross Europe and the USA on marketsupport mechanisms for renewable energyexpansion. However, the rate of growth willdepend on the advancement in technologythat will ultimately lead to an improved pricefor electricity produced by PV cells.The buildings and utility segment arebelieved to expect a large volume increasein the use of photovoltaics due to theconcern about energy and the environmentin the industrialised world. The Rural Off-Gridsegment is expected to show similarexpansion. The following table shows theprojected capacity and generation from solarpower in Europe:Table 12-7Forest Solar Capacity (GW)and Generation (TWh) in Europe2010 2020Capacity Generation Capacity Generation1.6 3.6 3.8 8.2MWeMWe20015010050020181614121086420The graph below shows how the PV markethas grown over six years, from 1993 to 1999:Figure 12-17aGrowth of Global PV Market1993 1994 1995 1996 1997 1998 1999The following graph shows the maincountries that manufacture photovoltaic cells:Figure 12-17bGrowth of Global PV MarketFrance India Spain Rest of UnitedEurope Kingdom12.4.6 Forecast - CostThe average price for energy generatedby solar technology is expected to beapproximately 4-6p/kWh by 2020. If solargeneration techniques could reach this price,then solar technology would be able tocompete with other technologies in theRenewables Obligation.One of the main influences on the PV systemis the effect on the distribution system.As a PV system generates on-site, emissionfree electricity, transmission and distributionlosses are negligible. Yet if there were a lotof on-site generation, it would require a lot ofchange to grid support, and the DistributionNetwork Operators would incur largeadditional costs.58


12.4.7 FutureThe British government has approved thefirst projects under its £20 million ‘MajorPhotovoltaic Demonstration’ program.Eight medium and large-scale projects,representing a total PV capacity of 350 kW,will share £1.32 million from the Departmentof Trade & Industry. The £20 million for thefirst phase of the program was announced inMarch, but the government has alreadyprovided £5.4 million to develop 500 solarpoweredhomes and £4.2 million for 18 solarpowered public buildings.12.5 Stirling Engines12.5.1 IntroductionThe Stirling engine is an engine that is verydifferent from the internal-combustionengine. Stirling engines are used only insome very specialised applications, like insubmarines or auxiliary power generators foryachts, where quiet operation is important.Stirling engines are classed as externalcombustion engines. They are sealedsystems with an inert working fluid, usuallyeither helium or hydrogen. In its simplestform the Stirling engine comprises acylinder, regenerator, piston and displacer,however, units with outputs higher than~1kWe tend to be multi-cylinder.Stirling Engines are generally found insmall sizes (1 - 25 kW) and are currentlybeing produced in small quantities forspecialised applications.Figure 12-19Stirling EngineFuel is burned continuously outside theengine to maintain the upper-cylinder at hightemperature while circulating water around itcools the lower end. Power is derived fromthe pressure swing as a fixed quantity of gas(generally air, nitrogen or helium) is alternatelyheated and cooled, forcing it back and forthbetween the two temperature zones,via the regenerator. The displacer movingapproximately 90 o in advance of theworking piston moves the gas.The regenerator is a heavy matrix offine wires that acts as repository forheat during the cooling pass, to bereturned on the heating pass.Based on this concept there aremany different combinations, alleither Kinematic or Free-PistonStirling Engines (FPSEs).FPSEs are single-cylinder machinesthat tend to be small and are usedin micro-CHP technology.Table 12-8Characteristics of Stirling EnginesSize Range


12.5.5 DisadvantagesThe reputation for high costs has preventedthe Stirling engine from becoming morewidely used. Doubts over their power outputcapability has also contributed to theproblem. Also, the engines inability tomodulate output and the length of time andpower input required to start the unit are nothelping the commercialisation of theseengines. Research and developmentin this field has helped manufacturesovercome these problems and enginesare now beginning to reach performancefigures that should be acceptable insome applications.12.5.6 Non-domestic CHP(mini-CHP)Stirling engines have the capability to meetthe requirements of mini-CHP. They operatewithout valves or an ignition system, and insome cases without oil lubrication, thuspermitting long service intervals and lowrunning costs. Stirling engines can maintainreasonable efficiencies even at small-scale.Stirling engines today tend to be sized at thelower end of the mini-CHP range, generallyunder 25 kWe.Modern Stirling engines can run at a similarspeeds to Internal Combustion (IC) enginesand, like their IC counterparts, tend tooperate at lower speeds for CHPapplications to extend operating life.In practice most kinematic Stirling enginemicro-CHP systems run at 1500 rpm driving4-pole generators to deliver power at 50 Hz.Of all reciprocating engines, Stirling enginesappear best suited to small-scaleCHP applications.12.5.7 Micro-CHPTable 12-10 lists the technical capability ofcompanies that are leading contenders in themicro-CHP market.Table 12-9Comparison of Significant Stirling Engine DevelopmentsEngine Cylinders Power Electrical Heater Gas[kWe] Conversion Temp.(LCV) [ o C]WhisperGen 4 0.75 10% 650 N2PPS16ACSunPower/BG 1 1.0 28% 550 HeRE100FPSESTC/ENATEC 1 1.0 23% 650 HeRE100FPSESIG1 1.0 1.2 15% 650 He(Switzerland) FPSESigma PCP1-130 1 3.0 23% 700 HeSolo 161 2 3-10 30% 650 HeKawasaki 1.0 1.2 27% (650) HeModel VFPSEMitsubishiNS-03M 1 3.8 36% (780) HeToshiba NS-03T 2 4.1 34% (820) HeTaminTESE004 1 1 (22%) 650 AirTable 12-10Leading Companies in Micro-CHP ProductionFigure 12-21Whispergen Stirling EngineCylinders Gross Overall Net Elec. NetElec. Eff. Conv. ThermalOutput (LCV) Eff. OutputMicrogen 1 1kW - 28 15kWENATEC 1 1kW 28% - 14kWSIG-SEM 2 - 23% - 6kWSigmaPCP 1-3CA 1 3kW 96 23 9kWWhisper Tech 4 0.75kW - - 6.2kWPPS1 6AC60


12.6 Wave and Tidal Energy12.6.1 IntroductionThe main obstacle for wave and tidalenergy is the cost per kWh produced.The equipment needed for tidal power maydamage the environment; also there is alack of efficient air turbine generationsystems for waves. To overcome theseobstacles, research needs to be carriedout on new generation devices.The installation of new under-watertransmission lines would also benefit matters.12.6.2 TechnologyTidal PowerTo produce electricity from the tides, an areaof water is sealed off and the large quantitiesof water that come in and out are used togenerate electricity. This is a well-establishedtechnology in operation in several countries.Wave PowerThe kinetic energy in the waves is convertedto electrical energy on floating platforms viaair turbines. This technology is mainly beingdeveloped in Europe and Japan. Waveenergy generation devices fall into twogeneral classifications, Fixed and Floating.12.6.3 Generating DevicesFixed generating devicesFixed generating devices, which are mountedeither to the seabed or shore, have somesignificant advantages over floating systems,particularly in the area of maintenance.However, the number of suitable sitesavailable for fixed devices is limited. LIMPET(Land Installed Marine Powered EnergyTransformer), the world’s first commercialwave power station, has been connected toUnited Kingdom’s national grid.Figure 12-22Limpet Wave Energy TurbineLocated on the Island of Islay, off the WestCoast of Scotland, the site will generate500 kW. The company feels offshore is theway forward, because waves are morepowerful before they hit land. There is abigger market for offshore wave power,as more power can be generated, and ithas a lower visual signature.Much research is occurring internationallyto develop oscillating water columns,including the OSPREY and floating columns,such as the Japanese Mighty Whale,(see figure 12-23).Figure 12-23Japanese Mighty WhaleResearchers at Lancaster University aredeveloping an offshore wave-poweredelectricity system, the Frond Wave Generator.A floating paddle-like collector surface islocated on the end of a long lever to capturewave movement due to its buoyancy.The lower end of the lever drives a hydraulicpower system that is fixed to the seabed,and the floating section can rotate toface prevailing waves at all times.The manufacturers responsible have alsolaunched the Stingray tidal power generatoroff the coast of the Shetland Islands.Another technology, the TAPCHAN,or tapered channel systems, consist of atapered channel that feeds into a reservoirthat is constructed on a cliff. The wavesincrease in height and enter the reservoir.The stored water is then fed through aKaplan turbine. Unfortunately, TAPCHANsystems are not suitable for allcoastal regions.Floating DevicesOcean Power Delivery (Edinburgh) isdeveloping Pelamis, a 750 kW floatingoffshore device. OPD plans to deploy itsdevice in 2002, and it is presently takingforward research and development projectsto reduce risk and tackle areas ofoutstanding uncertainty to maximise theopportunity for a successful ScottishRenewable Orders project. OPD plans toevaluate a 1/7th-scale model in the sea laterthis year.The Salter Duck, Clam, Archimedes waveswing and other floating wave energydevices generate electricity through theharmonic motion of the floating part of thedevice, as opposed to fixed systems whichuse a fixed turbine which is powered by themotion of the wave. In these systems,the devices rise and fall according to themotion of the wave, and electricity isgenerated through their motion. The SalterDuck is able to produce energy extremelyefficiently, however its development wasstalled during the 1980s due to amiscalculation in the cost of energyproduction by a factor of 10 and it has onlybeen in recent years when the technologywas reassessed and the error identified.Figure 12-24Archimedes Wave Swing12.6.4 Current StatusWaveCosts of wave power equipment aresignificantly higher than wind generationplants, due to the developmental nature ofthe plant. It is however felt possible thatcosts could ultimately fall to a similar level tosmaller wind plants. The current status ofthese technologies is fairly advanced.There are several fully operationaldemonstration and commercial plants forboth tidal and wave electricity generation.61


3110067 40 64494138152119 4133NorthAmerica13141133241620243640507410It is the cost of the electricity producedthat is preventing this power source fromcompeting with fossil fuels. Under the thirdScottish Renewable Orders there arecurrently 3 wave energy projects contractedfor a declared net capacity of 2 MW.Unfortunately under the fifth Non Fossil FuelObligation (NFFO) in England, Wales andNorthern Ireland there are no waveenergy projects in 2002.There are several advantages for waveenergy production. Wave energy doesn’tcreate or emit greenhouse gases.The production of electricity by waves isnot affected by changes in the weather,is predictable and is in phase with seasonaldemands, i.e. more electricity producedin winter.3329 4049 45 64 50677062 6349 55482619Africa1813SouthAmerica2933872517154211 122196Europe50 2334153817Figure 12-25Wave Energy DistributionFigures in kW/mrate) and 6p/kWh (15% discount rate).This is a lot lower than earlier estimates ofthe price of electricity from tidal technologies.At these prices, tidal energy could become,or would be close to being, economicallyviable within the Renewable EnergyObligation. These predictions now need tobe verified through a demonstration project.Even if these predictions are verified, tidaltechnology devices would still not be trulycommercially competitive with electricitysupplied from the grid at today’s costs;142762Asia4014261320131212.7 Wind Energy175012.7.1 Introduction42413063Wind power has become economically viablein the last few years in some regions dueto advances in technology. Electricity isgenerally generated from wind by ahorizontal axis system with the alternatorbeing linked directly with the rotor.Electricity generation from wind is still verymuch in the demonstration and investigationstage. Time is needed to see if the82010Australia4078 75 30 40 863 4384 7227 2462TidalSeveral devices have been proposed, yetthere is no agreement on the best design.Tidal generation devices do work, it is findingthe method of generating electricity that ischeap enough to compete with othergeneration sources that is proving difficult.There is currently very little information onlong-term operating figures and littleoperating experience to give evidencewhether one system works better thananother does. The most advanced tidalgenerator concept is that proposed byMarine Current Turbines Ltd. (MCT).MCT propose to demonstrate its conceptat~300kW scale near Lynmouth in NorthDevon. European Commission (EC) fundinghas been given and MCT is preparing aproposal for further DTI funding to thisscheme. This project should help usunderstand the commercial challenges andoutlooks for this specific device.Independent studies on the MCT concepthave shown that predicted energy costs fromit could be between 3.4p/kWh (5% discountFigure 12-26 Typical Wind Farmfurther development would be required toachieve true commercial competitivenesswith the grid today.The United Kingdom has the potential toproduce all of its electricity by harnessingjust 0.1% of the energy of its shores due towaves, according to a EuropeanCommission Study. The wave powerlevels in the UK are among the highest inthe world.techniques being used are correct fordifferent environments, and the cost is still aproblem, as is linking the turbines to a gridsystem. The unreliability of using a sourcesuch as wind means this technology maynot be suitable for many communities, andthe need for electrical storage for those notconnected to a grid poses a major hurdle.However, the UK has some of the bestwind profiles in the world, making it anideal testing ground for this rapidlyadvancing technology.


Capacity (MW) Installed900080007000600050004000300020001000012.7.2 TechnologyOf all the renewable energy productiontechniques wind is the most cost effective interms of £/kWh. Almost all countries canexploit wind power and it can be used toserve remote communities. Below shows theinstalled wind capacity of the leading windgeneration countries around the world:Figure 12-27Installed Wind Capacity in January 2002DenmarkGermanyIndiaItalyNetherlandsSpainUnited KingdomUnited StatesRest of World12.7.3 Current StatusDenmark has traditionally led the marketin the manufacture of wind turbines.There were 13 turbine manufacturers inDenmark in 1997. Wind turbines can rangefrom those in the low kW area right up to 3MW turbines. The commercialisation of largerunits has been delayed due to the lack ofdemand from the electric utilities. There is aneed to produce standard equipment in thisgeneration system and new storagesystems are required to accompany theturbines. This would help reduce the capitaloutlay and make wind generation morefinancially sound. Further economicincentives made by the government toelectric utilities to use wind energy wouldhelp this technology.Running and CostsModern wind turbines are expected torun for about 12,000 hours, and aredesigned to last approximately 20 years.The average price for a fully installedwind farm is £640/kWe. The timetaken to service the turbines isvery small and done whenthe turbines are not in use (no wind).The newer equipment has lowermaintenance costs of around 1.5% -2% per year of the original investment.63TWH200180160140120100806040200The standard turbines used are the 600 and750 kW machines, although the biggermegawatt machines are used where area forthe turbines is limited, or offshore.CapacityFigure 12-28 shows the trend in installedwind capacity and generation in the UK inthe last six years. As can be seen there is asteady rise in both.On-shore wind turbines have a declared netcapacity of 0.43 in the UK This means that a1MW turbine would be expected to make,on average, 430 kW of electricity every hour.No figures are available for offshore units.In 1999, the wind capacity in the UK wasnearly three times the capacity in 1994,while electricity generated from wind hasincreased by more than threefold overthe same period. This is attributed toimprovement in technologies together withthe better siting of wind farms.Figure 12-29 shows a comparison ofaverage growth rate per year betweendifferent technologies. As can be seen windtechnology is growing faster than any othersector, with solar photovoltaic technologyalso growing rapidly, in second place. As canbe seen from Figure 12-30, the number ofcontracted projects for wind power hassteadily risen every year. Projects contractedwithin NFFO account for roughly half the totalinstalled capacity in the UK, but this valuedoes fluctuate as contracts expire.Figure 12-31 shows the amount of energyproduced from wind power in terms ofthousand tonnes of oil equivalent:12.7.4 FutureBritish energy supplier Bizzenergy hascreated a new company to raise £50 millionto build six wind farms with 100 MWcapacity. Most of the facilities will be situatedin western Scotland, with the first expectedto be in operation within 18 months.Figure 12-28Total UK Installed Wind PowerCapacity and Generation1996 1997 1998 1999 2000 2001The Renewables Obligation forces electricitycompanies to supply 10.4% of their powerfrom renewables by 2011.Utilities in Scotland have already announcedinvestment plans of £1 billion in renewablesover the next decade, and 5,000 new windturbines are planned in addition to elevenwind farms currently in operation.The British government has approved thelargest offshore wind farm in the country,to be based 7 km off the North Wales Coast.National Wind Power Ltd will construct theNorth Hoyle facility by autumn 2003,with 30 Vestas turbines and a total capacityof up to 90 MW. The future growth of windenergy is difficult to predict, but it is fairlycertain the UK will see a substantial increasein its use. Figure 12-32 shows the IEA’sprediction for wind energy.12.8 Market EvaluationThis section looks at the maximum potentialmarkets for the emerging technologiescovered below. In many cases figures aregiven also for likely penetration of thosemarkets, but only where that information isreadily available. Finally a brief section onmarket penetration problems aims to listthose issues other than interconnectionwhere difficulties are likely to be found.12.8.1 CHP12.8.1.1 Current Installed CapacityThe installed capacity and the amount ofelectricity generated by CHP schemes in2000 in the UK, Germany and the EU areshown in Table 4.1 1,2,3 . In absolute terms,there is more cogeneration capacity inGermany than in the rest of Europe, thoughGermany is close to the EU average ofaround 11%. There is currently 4.6 GW eof installed CHP capacity in the UK, whichrepresents around 6% of the country’s totalgeneration capacity.Over the last decade, capacity in the UKhas more than doubled, representing anaverage growth rate over the period of 7%per annum. A growth rate of 9% wasachieved in 1999 with a net increase incapacity of 354 MWe (this breaks down as414 MWe of new capacityadded while 60 MWe was retired) -a significant improvement compared torecent years. Growth depends on therate of retirement of old plant as well asthe rate at which new plant are built.


Table 12-11Installed Cogeneration Capacity and Electricity Generation in 2000Installed Electrical CapacityElectricity GenerationCHP CHP Share of Generation CHP Share ofCapacity Total Capacity from CHP Generation (%)(GWe) (%) (TWh)UK 4.6 6 23.3 6EU-15 73.6 11 29.4 10Annual Percentage Growth Rate30%25%20%15%10%5%Figure 12-29Global Trends in Energy Use (1990-1999)The European Commission set a target in1997 to double cogeneration from 9% to18% of total EU electricity generation by2010 (Ref. 4.2). In 2000, electricity fromCHP schemes accounted for an average11% of gross electricity production in theEU (Ref. 4.2). Countries with a highproportion of CHP electricity are Denmark,the Netherlands and Finland with around62%, 53% and 36% of gross electricityproduction respectively (Ref. 4.3). However,in Germany the amount of cogeneration hasfallen in recent years, due to reductions inenergy costs because of liberalisation ofenergy markets.12.8.1.2Projected Cogeneration CapacityThe prospects for CHP growth in 28countries across Europe have beenexamined in the recent ‘future cogen’project (Ref. 4.2). Four different futurescenarios were modelled as follows:Present policies - current energy policiescontinue, particularly those affecting CHP,including changes expected. Energy sectorliberalisation in Europe is expected tobe complete by 2010.Technology developments are evolutionary,not revolutionary.(1) Heightened environmental awarenessbased upon present policies, but withextra benefits for ‘green’ technologies.This involves including the externalbenefits of CHP through theintroduction of a carbon tax andfaster technology developments.(2) Deregulated liberalisation involvescontinued liberalisation of Europeanenergy markets, but with no incentivefor smaller decentralised generation.Consequently, a few centralisedgenerators, who strongly influenceelectricity prices, will dominate theelectricity market. The result is that CHPbecomes un-competitive, with plantbeing closed, leading to less CHP output. This is the worse case scenario.(3) A post-Kyoto world where CHPbenefits are fully included in thetechnology cost. Micro-CHPbecomes technically and economicallyfeasible, and fuel cellCHP becomes possible, withincreased investment into ‘cleaner’technologies in a world tied toKyoto. Flexible mechanisms,such as emissions tradingand Joint Implementation,provide new finance for CHP.Economic and energy policiesare focused on decentralisedgeneration and Europeachieves major environmentalbenefits from increasedgeneration mix efficiency.This is the best case scenario.The results from the model for the UK andthe European Union are summarised inTable 12-12. It should be noted thatscenario 4 assumes the wide-scaleuptake of micro-cogeneration.However, it is only under this scenariothat significant growth occurs andthe European Commission’s targetof 18% electricity generation fromCHP by 2010 is achieved.12.8.2 Fuel CellsMarkets such as portableapplications and batteryreplacement, where a high cost perkWh of energy is prevalent, hold someof the largest, near-term potential marketsfor fuel cells. Buses and cars have thepotential for a huge, longer-term fuelcell market, and most automobilemanufacturers have an R&D scheme inplace. Significant sales are expectedto be in place around 2010, with themarket at around $10 billion.It is believed that fuel cells canmake a contribution to energyproduction in the UK in themedium-term.Capacity (GW)Thousand Tonnes of Oil EquivalentNumber of Contracted Projects0%-5%8070605040302010090807060504030201004035302520151050CoalNuclearOilHydroElectricNatural GasGeothermalSolar PVWindFigure 12-30Contracted Projects for Wind Generationin England and Wales1990 1991 1995 1997 1998Figure 12-31Total equivalent Energy Producedfrom Wind Power in the UK19891990199119921993199419951996199719981999Figure 12-32Forecast Wind Capacityand Electrical Generation in OECD2010 202064


Table 12-12Forecast CHP Capacity (GWe) under Different Scenarios 12.2Scenario 1: Present Policies2000 2005 2010 2015 2020UK 4.6 5.4 6.5 8.1 10.6EU-15 73.6 76.7 80.6 88.6 94.7Scenario 2: Heightened Environmental Awareness2000 2005 2010 2015 2020UK 4.6 6.3 8.8 11.5 15.3EU-15 73.6 80.3 90.7 105.3 124.3Scenario 3: Decentralised Liberalisation2000 2005 2010 2015 2020UK 4.6 5.0 5.1 6.2 7.5EU-15 73.6 71.2 69.6 73.5 81.4Scenario 4: Post-Kyoto2000 2005 2010 2015 2020UK 4.6 8.3 15.9 22.2 27.2EU-15 73.6 87.9 134.8 166.1 194.8The UK has green house gas commitments,and fuel cells could play a major role inmeeting these.Generation from the use of solar photovoltaicin the United States is forecast to increaseby 26.7% a year over the next 25 years,according to the US Department of Energy.Problems associated with thisPV output will rise to 880 GWh by 2025,technology are:from 40 GWh in 2002. Utilities and private- Costpower producers will increase generating- System complexity and the need forreformers in many applicationscapacity of PV from 20 MW in 2002 to 360MW in 2025, representing an annual increase- Commercial and financial risksof 13.9% 12.4 .12.8.3 Micro-turbinesLike fuel cells, the transport industry is aProblems associated with this technologyare:large potential market for this technology, - Cost primarilyparticularly with the arrival of hybrid vehicles.- Unreliable in some casesHowever, in the near-term, micro-turbines arelikely to be limited to niches in the market- Storage system may be requiredwhere they offer a distinct operational12.8.5 Stirling Enginesadvantage. They would be suited inA large market for Stirling engines lies incountries with a large difference betweenthe residential or portable small-scale powerelectricity and gas. This technology is alsogeneration area. The marine area hascapable of produce high-grade waste heat,consistently provided a steady marketmaking it highly beneficial to the combinedfor this technology and the cooling forheat, power and cooling market.equipment such as microprocessors andProblems associated with this technologyare:superconductors is another potential market.Market sizes for CHP are covered in- Noisysection 4.1.- Designed to run once per dayProblems associated with this- Not designed for repeated start/stopstechnology are:12.8.4 Solar Cells• Reputation for high costsThe rate of growth of this renewabletechnology depends on two issues:• Doubts over power outputDiscussions across Europe and the USA• Inability to modulate outputon market support mechanisms andadvancement in technology. The largestpotential market for PV lies within thebuildings and utility segment, and theRural Off-Grid sector is also a majorpotential market.• Length of time and power input tostart the unit are poor12.8.6 Wave and Tidal EnergyCurrently the high cost of equipment,and high cost of electricity produced,is preventing this technology from competingwith fossil fuels. The latest concepts in tidaltechnology do allow energy to be producedfor 3.4 to 6p/kWh and at these prices tidalenergy would be close to being economicallyviable with the Renewable Energy Obligation.A recent report has however recommendedthat Britain should re-consider an 8 GW tidalbarrage, as declining costs have made a tidalbarrier in England worth reconsidering.The report claims it would cost £6.2 to £8.4billion to build an 8,640 MW tidal barrieracross the Severn Estuary, which couldgenerate 6% of England’s electricity 12.5 .That is 40% less than the cost forecast16 years ago.True competitiveness with today’s grid wouldrequire further reduction in cost. However,wave power levels in the UK are among thehighest in the world and the UK is thereforeone of the most promising markets.Problems associated with this technology are:- Cost of equipment andelectricity produced12.8.7 Wind EnergyThe UK has some of the best wind profilesin the world, giving it a large potential marketfor wind generation technology. Wind is themost cost effective of all the renewabletechnologies considered here, and becauseof the ability of every country to exploit windpower, it has one of the largest markets.Wind is the fastest growing technology,with an average growth rate of nearly 25%between 1990 and 1995. The RenewablesObligation forces electricity companies tosupply 10.4% of their electricity power fromrenewables by 2011 and wind could beresponsible for a large quantity of this.The global market for wind turbines isforecast to surpass US$16 billion by 2007.A total of $5.5 billion was invested in newlarge turbines around the world in 2001 andin 2002, and a new report predicts that theglobal market will grow at an average annualgrowth rate of 24% to reach $16 billion by2007 12.6 .Problems associated with this technology are:- Unreliable- Electricity storage may be needed65


12.9 Other ProblemsAll generation technologies suffer frominterconnection problems. A list of typicalconnection problems is given below:- The cost of interconnection- Synchronisation to the grid- VAR Control- Effect of harmonics(c.f. power electronics interface)- Protection requirements (O/U voltage& frequency, LOM, reverse power)Traditionally, a connection “box” has beenrequired to deal with the technical issues.Such boxes are expensive, and requireindividual approval from the local electricitydistributor. In the future some smallersystems may use simpler, cheaperequipment – see section 3 for more details.12.10 LegislationThere is a significant amount of legislationand guidance notes that have affected theinstallation of newer alternative technologygeneration plant. This section aims to coverareas where such issues have not onlyhindered, but also helped with theirintroduction. This section does not covergovernmental issues such as OFGEM, NETAand renewables legislation.Legislation is currently focused on reducingemissions of greenhouse gases and otherharmful emissions. As regards generation,reduction of CO2, NOx and SOx isfundamental to policy though otheremissions do not escape attention.In particular, the UK has a legally bindingcommitment under Kyoto protocol to reducegreenhouse gas emissions by 12.5% by2008-2012 against the 1990 levels and adomestic goal of reducing CO2 emissionsby 20% by 2010. In addition, the UK hasintroduced a climate change levy, which isbased on energy rather than carbon contentof fuels, and will not be imposed on households.This approach is unlikely to encourageless carbon-intensive fuels.Aside from these governmental drivers,the issue of electrical interconnection is likelyto be the main issue for installation of plant.CE marking is also covered, as it is both abarrier for introduction, but also a safetyscreen for customers.12.10.1 Electrical InterconnectionThe main issue affecting the introductionof new emerging technologies is that ofelectrical interconnection to the network.The existing guidelines, G59/1, which areaccepted by network operators, apply toplant of 5 MWe (MW electrical) or less,and refer primarily to rotating plant.The constraints applied by these guidelinesare generally considered to be far tooonerous for smaller plant of under say 50kWe, and especially for residential generationat around the kilowatt level. As a result,two new sets of recommendations havebeen written:G77: Photovoltaic plant under 5 kWe(planned to be replaced by G83)G83: Small generating plant up to 16Aper phase (Issued 2002)Engineering Recommendation G77 hasbeen published by the Electricity Associationto provide simplified guidance for theconnection to the mains power network ofsmall PV generators on domestic residences.G77 covers the connection of inverterconnectedsingle-phase PV generators up to5kVA to public distribution networks. Its aimis to encourage the use of ‘approved’inverter equipment and recognisedconnection procedures in order to lessenthe need for DNO (Distribution NetworkOperator) personnel to perform local tests.It doesn’t cover practical or safety issues.(The DTI has recently published a Guide tothe installation of PV systems that doescover practical and safety issues.)Although G77 is only a ‘recommendation’and therefore not mandatory, it has beenagreed by all the DNO companies.Applications that stick to G77 are likely to beprocessed more quickly.From G77, G83 was developed to coverdomestic interconnection in general.Whilst G83 has now been issued, it hasnot yet replaced G77 as of the beginningof 2003. When this does happen, it isbelieved G83 will be reissued as G83/1.The introduction of these guidelines shouldgreatly assist the introduction of smallergenerating plant. Previously the cost ofcomplying with G59/1 could be almost asmuch as the cost of the small generationplant. It is now believed that this cost shouldbe cut substantially. It is also believed that upto 2 consortiums may be attempting todevelop a low cost interconnection device forsmaller plant.12.10.2 CE MarkingThe manufactured unit when sold intoEurope should be marked with a CE mark.Essential requirements for this are compliancewith the Machinery Directive, the EMCDirective and the Low Voltage Directive.In addition, the manufacturer should keep atechnical file, risk assess the equipment andaddress any problems, and finally shouldproduce a statement of conformity.Compliance with the three directives listedabove is compulsory, so minimal extra workshould be required to achieve conformity,with the onus on the manufacturer orimporting agent to show that conformity.The mechanical design is primarily coveredby “The Supply of Machinery (Safety)Regulations”, which implements“The Machinery Directive”. It covers a widerange of health and safety requirements fromdesign, to maintenance and operatinginstructions. Most machinery supplied in theUK must comply with its requirements, andgeneration plant should be expected to beincluded in this. Guarding should conform tothe guidelines given in BS EN 292 “Safety ofMachinery”, and the manufacturer should riskassess the plant as shown in BS EN 1050,“Safety of Machinery”. In addition, the siteoperation of the plant must also be riskassessed before operation, and themanufacturer should maintain a technicalfile, detailing calculations and other technicalinformation.The precautions necessary to avoid dangerfrom electrical systems, equipment andapparatus are entailed in the Electricity atWork Regulations 1989. The onus of theseregulations is to assess the activities that useelectricity and to define all foreseeable risks.All electrical equipment must therefore bedesigned, constructed, installed and tested tomeet the technical requirements of theElectricity at Work Regulations, the LowVoltage Directive and the ElectromagneticCompatibility (EMC) Directive. In addition,wiring should conform to the Institution ofElectrical Engineers (IEE) Wiring Regulations16th Edition 1992.Whilst the regulations above may soundonerous, compliance with them should befairly straightforward if safe and sound designpractices have been used throughout.The main burden will be the cost of CEmarking assessment by third parties.Whilst this is a real cost, the achievementof a CE mark can be beneficial as amarketing tool to show how far advancedthe equipment is.66


13The Role of EffectiveEnergy EfficiencyEnergy efficiency became an increasing partof the collective consciousness with theOPEC oil embargo in 1973, when bothpoliticians and average citizens realised theeconomic importance of energy (as wellas the risks associated with foreign oildependence). Following the Rio Earth in1992 the world in general embarked on aglobal effort to address the damagingeffects of climate change, caused in themain by the inefficient use of energy,primarily that in transport (cars etc.)and in electricity generation and utilisation.Many organisations have been set up,both nationally 13.1 and internationally 13.2 ,in an effort to address the damaging effectsof climate change (for more information onthis please see Chapter 10).For example the current priorities of theEnergy Saving Trust 13.1 are:• To stimulate energy efficiency inUK households and achieve social,economic and environmental benefits• To create a market for clean fuel vehicleswhich will deliver local and globalenvironmental benefits• To stimulate a market for renewableenergy which will achieve social,environment and economic benefits.The main reason for focusing on energyefficiency is that, for example, an inefficientprocess may use twice as much energy asan efficient process, and every additional unitof energy consumed results in power stationneeding to burn more fossil fuels in order togenerate it. Therefore by reducing theamount of energy required, we can reducethe requirement for (additional) powerstations and reduce the damage inflictedon the environment. For example,one quarter of the UK’s carbon dioxideemissions every year originates from theenergy we use to heat and light our homesand run an increasing number ofhousehold appliances 13.1 .In fact the average home emits more carbondioxide (in the UK) than the average car.There are three levels at which the messageof energy efficiency is being directed, andeach of the three levels has an important roleto play. The levels are:• Government• Industry (both generatingand consumptive)• IndividualsAn energy efficient economy, that isgovernment, individuals and industrycan grow without using more energy.For example, from 1970 to 2000, US energyconsumption grew by 45% whilst the grossdomestic product (GDP) increased 160%.In other words the amount of energy usedper dollar of GDP decreased 44 percentfrom 1970 to 2000 3 . Aligned with that isthe fact that using less energy in generalproduces less emissions, emissions in theUS increased 13% by 1999 above the1990 levels, however, during that sameperiod, energy use increased 14.9%.Finally, it should be recognised that,on average, energy efficiency and renewableenergy schemes create more localemployment than large scale powerproduction, making a further differencein the local communities who adoptthese schemes.13.1 The Role of GovernmentThe current UK government is publiclycommitted to lowering carbon dioxideemissions in order to achieve its 20%reduction target by 2010. There are anumber of initiatives being promulgated.Working with energy suppliers so thatthey invest around £450 million throughthe Energy Efficiency Commitment onimproving the energy efficiency of theircustomer’s homes by 2005.67


• Introduction of the Climate Change Levy.This is where businesses pay tax ontheir energy use, but those who userenewable energy are exempt fromthe Levy.• Introduction of a ‘Renewables Obligation’so that all gas and electricity companiesmust provide 10% of the energy theysell from renewable sources by 2010.• A promised £100 million in newrenewable technology such as thatdiscussed in Chapter 12.• It has also lowered value-added tax (VAT)from 17.5% to 5% on some energysaving materials; namely insulation andheating controls if professional installersfit those.13.2 The Role of IndustryIndustry uses on average one-third of allthe energy used, and some industries,for example, steel production consumes alarge amount of energy per unit product. It isin these industries that the focus has beenfor energy-efficient efforts and programmes.Apart from the direct introduction ofrenewable energy schemes (for which theuse of combined heat and power has beenthe most widely accepted) other measuresindustry can take include the use of energyefficient motors which can save at least 12%of the energy consumed 4 .As over 45% of the fuel burned bymanufacturers is consumed to raise steamfor one process of another, a typicalindustrial facility can save 20% or more byimproving its steam system. Measures suchas insulting the steam and condensatereturn lines, returning the condensate(i.e. water) to the boiler and even somethingas immediately detecting and stoppingany steam leaks can all contribute toimproved efficiency. Optimisation ofcompressed-air systems which are usedby many industry sectors, including tools,as power sources, and equipment usedfor pressurising, atomising, agitating andmixing can achieve between 20 to 50%energy efficiency improvements.In general business can take the followingactions in order to reduce carbon dioxideemissions.• Investment in energy efficient fluorescentlighting and knowledge of the optimumway to use it.• Build or remodel offices using energyefficient materials, insulation andalternative energy sources for the lightand heat.• Plant trees to offset the companiesgreenhouse gas emissions• Invest in energy efficient manufacturingprocesses and equipment• Use recycled materials where possible.Establish recycling programmes inthe workplace.13.3 The Role of thePower ProducersMany power producers and suppliers haveprogrammes, which encourage theircustomers to invest in energy efficientproducts that:• Lower consumer bills• Delay the requirement fornew generation• Reduce the emission of greenhousegases and other pollutants.However, technologies, which maximise theefficient generation, transmission and storageof energy, are also of fundamental interest.Renewable electricity generating schemesalso have the potential to play a major role(these are discussed in Chapter 12).These technologies include:Superconductivity - these are materialswhich have the ability to conduct electriccurrent with no resistance and very lowelectrical losses. They are being examinedfor application in a number of electricaldevices and in electricity transmission ashigh voltage cables, themselves.Energy Storage - can improve theefficiency and reliability of the electric utilitysystem reducing the requirements forspinning reserves to meet peak powerdemands, making better use of the efficiencybase load generation and allowing greateruse of intermittent renewable energy devices,for example solar energy. Energy storagetechniques include utility battery storage,flywheel storage, superconducting magneticenergy storage, pumped hydropowerand supercapacitors.There are other issues, which can positively,impact on an electricity generators efficiencyin delivering electricity to customers.These include:Demand side management, which areactions taken on the customer side of themeter to change the amount or timing ofenergy consumption. There are a widevariety of actions which can reduceenergy consumption and consumerenergy expenses.Distributed generation is where smallmodular electricity generators are sitedclose to the customer load which canenable utilities to defer or eliminate costlyupgrades in transmission and distributionsystem upgrades, whilst providingcustomers with more reliable energysupplies and a cleaner environment.13.4 The Role of the IndividualAs in most issues the individual often feelsunable to act so as to make a significantimpact on a global theme - however, withenergy saving, a significant impact can be,and is made, by the individual household.Things an individual household cando include:• Undertaking a home energy audit.• Hand wash the dishes.• Wash clothes in cold or warm water.• Turn down the thermostat.• Don’t overheat or over cool rooms.• Clean air condition filters.• Buy energy efficient compact fluorescentbulbs for your most used lamps.• Insulate the hot water heater.• Install low flow showerheads to useless hot water.• Weatherproof windows and doors.• Where possible walk, bike, car shareor use public transport.• Reduce waste, buy goods withminimum packaging, choose reusableover disposable, and recycle.• Recycle coolant from air conditioners.• Insulate walls and ceilings.• Replace windows with best energysaving models.• As you replace home appliances,select the most energy efficient models.68


13.5 Energy Efficiency in the UKThe following information, which focuses onthe situation in the United Kingdom, is takenfrom the March 2002 document issued byAEA Technology Environment and representsan analysis of the energy efficiency trendsin the UK 13.5 .The energy intensity of the UK economyhas been reducing at the rate of about 1.5%per year since 1950. This trend is due to acombination of factors: improved energyefficiency, fuel switching, and a decline in theimportance of energy intensive industries andthe fact that some uses, such as spaceheating, do not increase in line with output.For percentage user consumption, pleasesee Chapter 4 on the UK Electricity Marketand note that the figures used in thatChapter relate to primary energyconsumption, which makes the demandsplaced by the transport industry smaller.Total energy consumption increased byover 7% over the decade. Energy useincreased in all major sectors over thisperiod, except industry, which fell by about8%. Energy consumption in the residentialsector increased by 15% between 1990and 2000, services energy consumptionby 6.5% and transport energy consumptionby 13.5%.The Department of the Environment,Food and Rural Affairs (DEFRA) continuesto co-ordinate the UK’s climate changesprogramme, with increasing assistance fromthe devolved administrations: the ScottishExecutive, the National Assembly for Walesand the Department for the Environment inNorthern Ireland.A new Carbon Trust was set up in early2001 to take responsibility for a programmeof energy efficiency support measuresfor businesses.The UK has a legally binding target under theKyoto Protocol to reduce its greenhouse gasemissions to 12.5% below 1990 levels by2008-2012 and a domestic goal of a 20%reduction in CO2 emissions below 1990levels by 2010. The policies and measuresproposed to achieve these goals are listedin Table 13.1, and some of the key energyefficiency measures are describedfurther below.Table 13-1UK Policies and MeasuresPolicyMeasures/ programmesTo improve business’ • Climate change levy package, including negotiateduse of energy, stimulate agreements with energy intensive sectors, an Enhancedinvestment and cut costs. Capital Allowances scheme and a new Carbon Trust.• Domestic energy trading scheme.• Energy Efficiency Best Practice Programme.• Exemption of good quality CHP and renewables from theclimate change levy.• Market transformation measures.• Integrated Pollution Prevention and Control.To stimulate new, more • Obligation on electricity suppliers to increase the share ofefficient sources ofelectricity generated from renewable sources to at leastpower generation. 10% by 2010.• At least double the UK’s CHP capacity by 2010.To cut emissions from • European level (ACEA) agreements with car manufacturers.the transport sector. • Graduated vehicle excise duty (see taxation).• Reform of company car taxation (see taxation).• Additional expenditure on public transport.To promote better• A new Energy Efficiency Commitment (successor to theenergy efficiency in the Energy Efficiency Standards of Performance).domestic sector.• New Home Energy Efficiency Scheme in England andsimilar schemes in Scotland, Wales and Northern Ireland.• Affordable Warmth Programme.• Promotion of new community heating and upgrading ofexisting schemes.• More efficient lighting, heating and appliances.To improve energy• Improvements in the energy efficiency requirements of theefficiency in buildings. Building Regulations.To ensure the public • New targets for energy management of public buildings.sector takes a leading • Energy efficiency targets for local authorities,role.schools and hospitals.• Green travel plans.The Climate Change Levy is a new energy The Enhanced Capital Allowancestax applied to the business and publicScheme administered by the Carbon Trustsectors from April 2001 (excluding good gives 100% first year capital allowances forquality CHP and renewable energy).approved energy saving instruments forRevenue from the levy (expected to bebusinesses, who will be able to take this intoaround £1 billion in 2001/02) is beingaccount when calculating their corporationrecycled to business via a reduction inor income tax bills.employers’ National Insurance ContributionsThe Carbon Trust was set up inand £150 million of additional support forApril 2001 to provide a co-ordinated,energy saving measures. This additionaltargeted programme of support measuressupport takes the form of an Enhancedfor businesses investing in energy savingCapital Allowances (ECA) scheme andtechnology and practices. It will recyclethe new Carbon Trust. Energy intensivearound £100 million of climate changesectors can obtain an 80% discount in levylevy receipts over three years. It is currentlyrates if they agree to meet targets fordeveloping its programme, but elementsimproving energy efficiency or reducingwill include:carbon emissions.69


• A programme to accelerate the take upof existing energy efficiency technologiesbuilding on the Energy Efficiency BestPractice Programme.• The enhanced capital allowances scheme;• A Low Carbon Innovation Programme tosupport new and emerging technologies.The Energy Efficiency Best PracticeProgramme is the UK’s main energyefficiency information, advice and researchprogramme for organisations in the public andprivate sectors. The provision of site specificadvice (energy audits) is a growing part ofthis programme.A Domestic Emissions Trading schemewill begin trading in April 2002.The Government will provide support to kickstart the scheme by providing a financialincentive for companies to take on bindingemission reduction targets. Participants willbe able to bid in absolute levels of emissionreductions at prices set through an auctionto be held in April 2002.The Energy Efficiency Commitmentcomes into force in April 2002 and willensure electricity and gas suppliers help theirdomestic customers, particularly the elderlyand those on low incomes, to save energyand cut their fuel bills.The New Home Energy Efficiency Scheme(HEES) was launched in June 2000, andprovides grants of up to £1000 for householdsliving on low incomes for a range of heatingimprovements and insulation measures.The Affordable Warmth Programme hasbeen developed in conjunction with Transcoand will facilitate the installation of efficient gascentral heating systems and insulation in amillion homes by the end of 2005 through theuse of operation lease finance.The climate change levy is a major newenergy-related tax that came into operationin 2001. This is described in the section onprogrammes and measures, above. Rates oflevy are:• 0.15p/kWh for gas• 1.17p/kg (equivalent to 0.15p/kWh)for coal• 0.96p/kg (equivalent to 0.07p/kWh)for liquefied petroleum gas (LPG),• 0.43p/kWh for electricity.13.6 Energy Efficiency Assessment1990 to 2000The overall assessment of energy efficiencyis presented in this section.Two general indicators are generally usedto characterise the overall energy efficiencytrends: primary energy intensity (i.e. the ratioof primary consumption to GDP), and finalenergy intensity (ratio of final consumptionto GDP). Primary intensity provides anassessment of the energy productivity of thewhole economy. Final intensity characterisesthe energy productivity of final consumersonly. Final consumption, according tothe ODYSSEE definition, excludesnon-energy uses.Figure 13-1 shows a downward trend in bothprimary and final energy intensity over thewhole period 1970-2000. Overall the lastdecade, primary energy intensity has fallenfaster than final energy intensity, and so theratio of final to primary energy has increasedby 7.5%.The downward trend in energy intensitysuggests improvements in energy efficiency,but there may be other underlying effectssuch as changes in the structure ofthe economy.The recent increase in the ratio of final toprimary energy may be explained by theincreased proportion of energy use by thetransport sector. In this sector, there is littleconsumption of electricity so the differencebetween final and primary energy use ismuch less. The efficiency of electricitygeneration has also increased markedlyover the last decade due to theintroduction of combined cyclegas turbine plant.These effects have offseta recent trend towardsincreased use of0.8electricity in the0.7industrial sector,and increased0.6growth of the0.5services sector.Intensity kw0.40.30.20.10.0For industry energy consumption hasfallen by 4% over the period 1990 to 2000,whilst electricity consumption has risenabout 1% per annum. This against abackground of growth in the value ofthe manufacturing industry over thesame period.For households over the same periodthere has been little change per average floorarea, if natural fluctuations due to climateconditions are corrected for.For the service industry the value of thissector rose 20% over the period 1990 to2000, but energy consumption rose by only7%. Electricity consumption also increasedby 20% over this period due to increasedequipment uses, therefore any efficiencygains came through better space heatingand insulation, and turnover of old buildings.Figure 13-1Primary and Final Intensity for the UK,1970-20001970197119721973197419751976197719781979198019811982198319841985198619871988198919901991199219931994199519961997199819992000Ratio of final to primaryPrimary intensityFinal Intensity70


14The following summarises the state of current legislation in theUnited Kingdom. For details of the privatisation of the UK electricity industry,please see Chapter 4, and for possible future trends, Chapter 15.This chapter looks at the general position with respect to theUtilities Act, which received Royal Assent in July 2000, and is itselffollowed by a summary of more recent legislation.Current Legislation14.1 The Utilities Act 2000This Act represents one of the mostfundamental changes to the regulatoryframework for the industry and its structuresince privatisation. The most importantchanges arising from the Act are:• The creation of a new regulatoryauthority, the Gas and Electricity MarketsAuthority, GEMA• A new consumer body, energywatch• The separation of supply anddistribution businesses• The new electricity tradingarrangements, NETA.Whilst the Act provides the framework for theindustry a significant amount of secondarylegislation is also required, after consultationwith interested bodies.Originally the post of regulator was anindividuals appointment for the gas andelectricity industries respectively, which wasthen merged. It is now replaced by GEMAwhich is a corporate body comprising of 5executive and 6 non-Executive membersappointed by the Secretary of State andwhich determines strategy and decides onmajor issues. It is supported by the Office ofGas and Electricity Markets (Ofgem) whichconsults with interested parties on all keyregulatory issues.One of the Authorities key objectives isto protect the interests of the consumers,and also have due regard to the statutoryguidance on the social and environmentalobjectives, and to take into account thebroader social policies promulgated bythe government.The Act also established a Gas andElectricity electricity Consumers Council known asenergywatch as the primary body fordeveloping and driving the consumer’sagenda. It has a particular focus onprotecting the disadvantaged.The act provided energywatch with extensivepowers to investigate any matter relating tothe interests of consumers and to obtainnecessary information. It also has the dutyto investigate, seek to resolve andcommunicate information about complaintsby consumers against service providers.It also has a duty to publish information onthe performance of licensees against servicestandards set by the regulator.Licenses set out the legal restrictions onthe electricity and gas businesses andoccasionally they may be required to bemodified to regulate specific aspects oflicensees holders behaviour, for example toincrease the interest of consumers, or toreflect market changes. In the past severaltypes of licenses were in existence, and theywere unique and specific to the licensees.The Act introduced the concept of standardlicence conditions with the intention beingthat all holders of a particular licence typeare subject to the same conditions as far asappropriate. There will be clearly delineatedgroups of license for example, for generation;there is a set of conditions, which applies toScotland and another applying to Englandand Wales.The Act also separated supply anddistribution activities, which were permittedto operate together in the past. The Actmakes electricity supply and distributionactivities separate licensable activities witha bar on the same person holding bothan electricity supply and an electricitydistribution licence. In Scotland this has alsomeant that the composite transmission andgeneration businesses have had to separateinto 2 respective businesses.The Act also placed an obligation to worktowards the Governments social andenvironmental objectives. The socialdimension focuses on a number of groups insociety namely the disabled, the chronicallysick, pensioners, those on low incomes andthose living in rural areas.The Government has set up a FuelPoverty Strategy to ensure that by 2010no vulnerable person need risk ill healthdue to a cold home. In particular theGovernment wishes that the benefits ofincreased competition in the electricitysector are fairly distributed amongst allcustomer groups and that the poorestshould demonstrably benefit.The environmental objectives relate tothe duty to promote the efficient use ofelectricity and gas and to have due regardas to the impact of licensed activities onthe environment. The Government has acommitment to the goals of sustainabledevelopment, which includes energyefficacy, the targets for reduction in gaseousemissions and the targets for renewableand Combined Heat and Power.There has been an Environmental ActionPlan recently published by Ofgem andthe Government has requested that this isthe vehicle by which to progress theenvironmental aspects of the work.There has been suggestions that Ofgemshould focus on the potential for energyefficiency at all points in the energy chain,including electricity generation, transmissionand distribution, and should also be in aposition to quantify the benefits of anyactions. Also mentioned is the need topromote competition in generation andremoval of barriers to embedded generation.However, the Act also makes it clearthat although Ofgem has a responsibilityto the government’s wider policy goals,any implementation of social orenvironmental measures, which would havesignificant financial implications for eitherconsumer or for the regulated industriesmust be implemented by means ofspecific legislation.The following are recent legislative eventsrelating to the electricity industry 14.1 .71


RenewablesOn 1 April 2002, the Governmentintroduced an obligation on all licensedelectricity suppliers requiring them to supplya specified proportion of their electricity fromeligible renewable sources. That proportionwill rise from 3 per cent in the current year to10 per cent by 2010.Climate Change LevyIn the Chancellor’s 2002 Budget statementhe strengthened the existing policy to supportbusiness energy efficiency by announcingproposals to:• Freeze the climate change levy rates• Giving complete exemptions from theclimate change levy for electricitygenerated by good quality combined heatand power (CHP) or from coal minemethane. Implementations of theseexemptions are subject to EU Stateaids approval• Adding of heat pumps, radiant, warm airand solar heaters, energy - efficientrefrigeration equipment and compressorequipment to the list of energy-savingtechnologies, which can benefit from theenhanced capital, allowances against tax.This provision is also to be extended toequipment for leasing.Emissions Trading SchemeThe Government’s emissions trading schemewas launched on 2 April 2002. Thirty fourorganisations successfully bid to join thescheme for permits in an auction for permitsheld on 11-12 March 2002.Fuel PovertyThe Fuel Poverty Advisory Group, which hadbeen announced in the November 2001 UKFuel Poverty Strategy, met for the first time inMarch 2002. The Group is an Advisory Non-Departmental Public Body sponsored byDEFRA/DTI. Its primary task is to report onthe progress of delivery of the Government’sFuel Poverty Strategy and to propose andimplement improvements to regional or localmechanisms for its delivery.The Group consists of a chairman andsenior representatives from organisationssuch as the energy industry, charities andconsumer bodies. These members would berepresentative ex officio members rather thanindividuals, who should be able to take abroad and impartial view.In March 2002 the Department for Transport,Local Government and the Regions publishedrevised guidance on the decent homestandard and guidance on how sociallandlords can quantify the extent ofnon-decent housing within their stock to helpthem better deal with the problem.A decent home is one that meets thefollowing criteria:- Is above the current statutory minimumstandard for housing;- Is in a reasonable state of repair;- Has reasonably modern facilitiesand services;- Provides a reasonable degree ofthermal comfort.The Scottish Executive issued its draft FuelPoverty Statement in March 2002, invitingcomments on the way the Executive plansto tackle fuel poverty in Scotland. Again inMarch, Ofgem published its second annualreport on its Social Action Plan setting outprogress towards Ofgem’s aim to ensurecompetition benefits all customers and todevelop polices to help the fuel poor.Energy EfficiencyThe Energy Efficiency Commitment is anobligation (expressed as a total energy savingin TWh) placed by the Government on gasand electricity suppliers to encourage andassist their customers to make energysavings through measures such as cavity wallinsulation loft insulation, boiler replacementand energy saving light bulbs. Suppliers makea contribution to the cost of the measure ata level that will induce the customer to takeit up.The scheme, which began on 1 April,will run from 2002 to 2005 and the overalltarget on all suppliers has been set at a levelthat is expected to lead to estimated ongoingannual energy savings for consumers ofaround £275 million by 2005. There will bealso annual reductions in carbon emissionsof around 0.4 million tonnes by 2005.It is estimated that the scheme will costenergy suppliers around £3.60 per customer,per fuel, each year. The scheme focuseshelp on the fuel poor and companies willbe required to seek at least 50% of theirtarget fuel savings from disadvantagedcustomers.CHPIn the Budget it was announced that all CHPgenerated electricity would be exempt fromthe Climate Change Levy (CCL). This is a keymeasure that is likely to help set the sectoron course to meet the Government’s targetof at least 10,000MWe of CHP capacityby 2010.Previously, only CHP electricity used on siteor sold direct to other users had qualified forCCL exemption.In addition leased assets will now be eligiblefor Enhanced Capital Allowances (ECAs).This will be very supportive for CHP schemedevelopment. Most CHP developments relyon third party finance, some of whichinvolves leasing the capital assets.Previously leased assets were not eligible forECAs, so this new measure will provide anadded boost for CHP.Micro CHPIn the Budget domestic micro CHPinstalled under the Warm Front Teamwill attract the reduced rate of VAT.VAT on the installation of a range ofdomestic energy saving products wasreduced to 5% from April 2000.Micro CHP is a new technology that weexpect to make a significant contributionto domestic energy efficiency in the future.Reducing VAT on the cost of installationwill help to give this new technology auseful kick-start.72


15This chapter examines what may occur in twenty years time, starting withthe UK government’s vision of the energy system in 2020, and ending witha speculative look at alternative technologies for carbon dioxide reduction.The Future15.1 The Energy System in 2020It has been accepted that in order to achievethe requirement for the reduction in carbondioxide emissions, while at the same time asour indigenous energy supplies decline andthe existing energy infrastructure requiresupdating, there is a need to look forwardover the next 20 years. This is in order tohave in place the framework capable ofdelivering our environmental, security ofsupply, competitiveness and social goals.In reducing the carbon dioxide emissions thegovernment’s priority is to strengthen thecontribution of energy efficiency andrenewable energy sources, while open andcompetitive markets will remain vital fordelivering the required energy.In order to achieve the above challenges,the UK government has established fourgoals for its energy policy:1. To cut carbon dioxide emissions in2050 by some 60%, with real progressby 2020.2. To maintain the reliability ofenergy supplies.3. To promote competitive markets in theUK and beyond, helping to raise therate of sustainable economic growth andto improve the productivity; and4. To ensure that every home is adequatelyand affordably heated.So what will the energy system look like in2020? First of all it is envisaged to be morediverse than at present, with a larger numberof electricity sources and technologiesinputting into the system affecting boththe means of supply and the control andmanagement of demand.• It is thought that the majority of ourenergy will be imported either from orthrough an enlarged singleEuropean market.• Whilst the foundation of the electricitynetwork will still be the Grid, balancingthe contributions of the large powerproducers, some of the power will becoming from large off-shore basedplants including tidal, wave andwind farms.• There will be a requirement for backupcapacity for when weather conditionsreduce or cut off supplies fromthese generators.• There will be more local generation usingfor example biomass or local windand tidal sources.• These local generators will feed intolocal distributed networks, which in turnwill feed the Grid.• Heat will be increasingly co-generatedwith the electricity.• There will also be micro-generation fromCHP plant, fuel cells or photovoltaics.• Energy efficiency improvements willreduce overall demand albeit that thereis increased new demand for electricityas computers penetrate further thedomestic market and air conditioningmay become more widespread.• Buildings will become less dependenton the Grid with perhaps solar panelsproviding much of the heating.New homes could have zerocarbon emissions.• Gas will still form a large part of theenergy mix as savings from moreefficient boilers are offset by demand forgas for CHP, which in turn displaceselectricity demand.• Coal fired generation will play a smallerpart than today in the energy mix or belinked to CO2 capture and storage if thatever proves feasible either technically,economically or environmentally.73


The existing nuclear power stations willhave almost all reached the end of theirlife - if new nuclear power plant isrequired to meet the UK’s carbon targets,this will be subject to a later decision.• Fuel cells are anticipated to be playing agreater role in the economy initially asstatic devices in industry or as a meansof storing energy, for example to back uprenewables. However, they will eventuallybe increasingly used in transport.The hydrogen required for their operationwill be generated primarily by using noncarbon-basedelectricity.• Nuclear fusion will be at an advancedstage of research and development.• People will generally be more aware ofthe challenge of climate change and thepart they can play in reducing carbonemissions. Carbon content willincreasingly become a commercialdifferentiator as the cost of carbon isreflected in the price of goods andservices and people will choose thelower carbon options.15.2 Alternative Technology SolutionsThe following outlines some of the morespeculative ‘techno-fixes’ which have beensuggested in order to reduce the amount ofsunlight reaching the Earth to remove theheat-trapping gases from the air 15.2 .Please note that these, often extreme,measures have not been evaluated andcarry the risk of unexpected environmentalside effects.One proposed solution has been to spreadmillions of tonnes of iron over the oceansurface, which would stimulate the growth ofalgae, which in turn would consume carbondioxide from the ocean surface. The algaewould eventually die, sinking to the oceanfloor taking the carbon with them, and theocean would absorb more from theatmosphere to replace whatever the algaetook. However, the ocean currents mayquickly return the carbon dioxide to theenvironment and massive amounts of algaemay have unforeseen effects on the marine(and human) food chain! An alternative toalgae is to grow seaweed to absorb thecarbon dioxide - however an area half thesize of the United States would be requiredto absorb 40% of the carbon dioxide emittedat present, with unknown effects on the localecosystems and local climate.Another has been for aircraft to releasethousands of tonnes of sulphur dioxide intothe upper atmosphere every year where itwould combine with water to form tinydroplets of sulphuric acid, which wouldreflect the sunlight. However, this couldincrease the amount of acid rain and evenintensify the destruction of the ozone layer.Likewise a proposal has been made to burnsulphur to make clouds, but this wouldintensify the potential for acid rain.Alternatively giant space mirrors could beemployed to reflect sunlight away fromthe Earth (if it was ever technically oreconomically feasible to do so). If mirrors didnot work they could be replaced by billionsof reflecting balloons which would blocksunlight. Unfortunately there would be atendency for these to fall to Earth creating alarge litter problem!74


16Conclusions andRecommendationsThe electricity industry plays a central role inthe UK economy by producing transformingand supplying energy to all sectors.Electricity consumption as a percentageof the overall final energy consumptionhas risen year on year since 1970,from 11 to 18% in 2000. Electricity provided27% of the energy consumed by industry,21% of the domestic sector energyrequirements and 37% of the servicesectors total energy consumption.However, the supply and use of energy isalso a major contributor to emissions tothe environment. This is not only of thegreenhouse gases such as carbon dioxide,acidic gases such as sulphur dioxide andother pollutants associated with poor airquality, the energy industry also directly emitsliquid and solid wastes as well as being themajor industrial water extractor. Details arecontained in the various individual chapters,which examine each primary fuel in turn,and then examine the different inputs andoutputs. It is clear that energy use is a majorbuilding block in the compilation of anysectorial mass balance and it is anticipatedthat the information contained in this reportwill be used in existing and future massbalances within the Biffaward and otherschemes, by allowing the energy usage ofany process for which a Mass Balance isbeing performed to be related to a mass ofraw fuel input and the associated emissions.It is further anticipated that the supply anduse of energy will continue, and indeedincrease in for example, developing countriesdue to the human desire for heat, light andthe ability to perform work. This studyevaluated the four main power generationmethods, namely the use of oil, gas, coaland uranium to produce electricity via theheating of water. The different powergeneration methods produce differentemission levels depending primarily on theinput fuel and the overall process efficiency.This leads to the least emissions arising fromfirstly the generation of power via nuclearmethods, and secondly, the use of closedcycle gas turbines, which combines relativelylow emissions with high efficiency.The impact of electricity generation on waterand land is generally overlooked - with thefocus in the past decade being on globalwarming and gaseous emissions.For example, although nuclear power is themost beneficial in terms of actual gaseousemissions which is increasingly important interms of the Kyoto Protocol, it is the majoruser of water, and although the volumesof waste produced are low, the associatedradioactive solid waste will always bean issue.The adoption of the CCGT has had ahuge impact on the environmental emissionsdue to its high efficiency, but it is verysensitive to gas prices. Coal was thoughtto have been left behind in the ‘dash for gas’but it is making something of a revival as gasprices increase. The environmental burdenwith coal is large, not only with gaseousemissions but those to water and landfill too.It is clear that in the future there will be amuch increased use of renewable electricity,in particular in order for the UK to honour itsobligations under the Kyoto protocol.Indeed in September 2003 the DTIannounced that the UK will be buildingenough offshore wind farms to power onein six households by 2010. The cost ofrenewable power installations is stillrelatively high and so it seems thatgovernment support will need to continueor grow in order to ensure that the numberof renewable power generation installationstaking place in the next few years meetsits aspirations.In the past few years the UK electricitygeneration and supply businesses haveundergone a phase of intense restructuringand the majority of the acquisitions,mergers and de-mergers undertakenwere the result of commercial considerations.This has led to the closer integration ofthe energy suppliers and more details arecontained in the overall report.75


In the UK in particular, the overall emissionsassociated with the power industry had beendeclining due to the enhanced operatingefficiency of the existing nuclear powerstations and the increasing use of gas togenerate electricity via closed cycle gasturbine technology. However, as was pointedout in the body of the report, the increasingcost of gas is leading to an increase inthe use of coal, albeit with improvedenvironmental measures. It is considered bythe IEA for example in 2002, that while theUK will probably be able to meet the Kyototarget meeting the national target willrequire addition effort. Attention is requiredparticularly in the residential sector whereasthe Climate Change Levy focuses on thebusiness and public sectors.When combined with the government’scommitment to alleviating fuel poverty thatparticularly affects low income householdsin old, poorly insulated buildings, this couldimpact on the success or otherwise ofmeeting the national target.These days there is a NEED for electricity -people will no longer accept the switching offof lights, or even temporary non-availability.Social poverty is associated with the lackof electricity and this is not consideredacceptable in the 21st Century.Therefore the future decisions aroundelectricity generation will have to balanceeconomic, social as well as environmentalaspects, let alone those concerned withthe technology of fuel combustion.The IEA in 2002 made the followinggovernmental focused recommendationsfor the UK electricity market. They includedallowing the industry to settle into theNETA arrangements without interference,encouraging the full participation of thedemand side in balancing the market,consistency in regulation and the provisionof incentives for the transmission owner tobuild over the long term the infrastructureneeded to secure supply. With respect tonuclear power generation it recommended amore proactive attitude in the design andimplementation of a national policy, increasedmonitoring of the availability of infrastructure,equipment and manpower to enable ongoingsafe operations and clarification on how itintends to keep the nuclear option open.76


17References1.1 Michealis, Royal Society, Energy Mass Balance, Eyre, N.J., 1990,Gaseous Emissions due Electricity Fuel Cycles in the UK,ETSU Energy and Environment Paper Number 1, March 1990.1.2 Linstead and Elkins, Mapping UK Resource and Material Flows,Royal Society for Nature Conservation, 2001.1.3 Definitions and terminology pertaining to theElectricity Industry Verfaille and Bidwell Measuring eco-efficiency:A Guide to Reporting Company Performance.World Business Council for Sustainable Development. 2000.2.1 www.electricpower.com/consumer/ as of the 5th February, 20032.2 www.the-education-site.com/electric/history as of 5th February, 20033.1 International Energy Outlook 2003, May 2003, available athttp://www.eia.doe/iea/overview.html as of May 2003.3.2 As of February 24, 2003, the following Annex I countries had ratified,accepted, approved or acceded to the Kyoto Protocol: Austria, Belgium,Bulgaria, Canada, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Latvia, Lithuania,Luxembourg, Netherlands, New Zealand, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, and the United Kingdom.4.1 The Electricity Industry Review #6 The Electricity Association.January 20024.2 The US National Energy Information Centre, available athttp://www.eia.doe.gov/emeu/internationl/elecprih.htmlas of 26th November, 2002.4.3 The US National Energy Information Centre, available athttp://www.eia.doe.gov/emeu/internationl/elecprih.htmlas of 26th November, 2002.4.4 Department of Trade and Industry Official Figures available atwww.dti.gov.uk/energy/inform/site_installations/ dukes5_10.pdfas of 29th May, 20034.5 Department of Trade and Industry Official Figures available atwww.dti.gov.uk/energy/inform/ as of 29th May, 20034.6 The Electricity Industry Review #6 The Electricity Association.January 20024.7 United Kingdom: Environmental Issues. The US National EnergyInformation Centre, available athttp://www.eia.gov as of 29th November 20025.1 World Coal Institute, The Origins of Coal, 2002.http://www.wci-coal.com5.2 EM Database: coal.http://www.oeko.de/service/em/docu/data/emda0003.htmas of 23rd January, 20035.3 Michealis, Royal Society, Energy Mass Balance.5.4 World Coal Institute, The Origins of Coal, 2002, available athttp://www.wci-coal.com5.5 International Energy Annual 2001: World Energy Overview for 2000.http://www.eia.gov/iea/overview/html5.6 BP Statistical Review of World Energy, 2000 quoted in MINING Magazine,Vol. 9, P 103, 2001.5.7 EIA Country Analysis Brief, September 2001.http://www.eia.doe.gov/cabs/uk2.html5.8 IEA, 1993, Energy Balances of OECD Countries 1990 - 1991.5.9 World Environment News. ANALYSIS - UK polluting more thanksto a shift to coal.http://www.planetark.org/avantgo/dailynewsstory.cfmas of 21st of January, 20035.10 The Energy Files: Coal, Understanding Energy,http:/www.energy.co.uk/EFCoal.html5.11 The ExternE Project UK Report available athttp://externe.jrc.es5.12 UK Department of Energy Prospects for the use of Advanced Coal BasedPower Generation Plant in the United Kingdom.Energy Paper 56, HMSO, July 1988.5.13 Eyre, N.J., 1990, Gaseous Emissions due Electricity Fuel Cyclesin the UK, ETSU Energy and Environment Paper Number 1, March 1990.5.14 IEA, 1993, Energy Balances of OECD Countries 1990 - 19915.15 Digest of United Kingdom Energy Statistics, DTI, 20005.16 The Energy Files: Coal, Understanding Energy, available athttp:/www.energy.co.uk/EFCoal.html5.17 The ExternE Project UK Report available athttp://externe.jrc.es6.1 The Energy Files: Oil, Understanding Energy, available athttp://www.energy.co.uk/EFOil.html6.2 What is Oil?, available athttp://www.sjgs.com/oil.htmlas of 8th April, 20036.3 The ExternE Project UK Report available athttp://externe.jrc.es/2da1file1.html6.4 World Coal Institute, Electricity Generation from Coal, available athttp://www.wci.rmid.co.uk/web/list.php?menu_id=2.7.2.1as of 13th March, 20036.5 International Energy Annual 2001: World Energy Overview, available athttp://www.eia.doe/iea/overview.htmlas of 7th March 20036.6 BP Statistical Review of World Energy, 2000 quoted in MINING Magazine,Vol. 9, P 103, 2001.6.7 International Energy Annual 2001: World Energy Overview,World Crude Oil and Gas Reserves, Table 8.1, available athttp://www.eia.doe/iea/oillas of 7th March 20036.8 EIA Country Analysis Brief, September 2001 available athttp://www.eia.doe.gov/cabs/uk2.html6.9 The Energy Files: Oil, Understanding Energy, available athttp:/www.energy.co.uk/EFOil.html7.1 How Natural Gas is Produced, US Department of Energy, available athttp:/www.fe.doe.gov/education/gas_production.htmlas of 21st August 20027.2 The ExternE Project UK Report available athttp://externe.jrc.es/7a99file1.htmlas of 27th February, 200377


7.3 World Coal Institute, Electricity Generation from Coal, available athttp://www.wci.rmid.co.uk/web/list.php?menu_id=2.7.2.1as of 13th March, 20037.4 World Environment News. ANALYSIS - UK polluting more thanksto a shift to coal.http://www.planetark.org/avantgo/dailynewsstory.cfmas of 21st of January, 20037.5 International Energy Annual 2001: World Energy Overview, available athttp://www.eia.doe/iea/overview.htmlas of 7th March 20037.6 BP Statistical Review of World Energy, 2000 quoted in MINING Magazine,Vol. 9, P 103, 2001.7.7 International Energy Annual 2001: World Energy Overview,World Crude Oil and Gas Reserves, Table 8.1, available athttp://www.eia.doe/iea/oillas of 7th March 20037.8 Innovation and the Transformation to Clean Technologies:Life Cycle Management of Gas Turbine Systems Robert Anex,Sasidhar Velnati, Mark Meo, and Rex Ellington, and Mark Sharfman,available athttp://www.ou.edu/spp/turbine/paper.htmlas of 23rd January 20037.9 The Energy Files: Gas, Understanding Energy, available athttp:/www.energy.co.uk/EFGas.html7.10 EIA Country Analysis Brief, September 2001 available athttp://www.eia.doe.gov/cabs/uk2.html8.1 New Scientist, Inside Science, Atoms Unleashed, 18th January 2003.8.2 Nuclear Electricity 7th Edition, 2003, available athttp://www.uic.com.au8.3 International Energy Agency, Key World Energy Statistics, 2002.8.4 Outlook for the Global Nuclear Fuel Market to 2020, S Kidd,The Uranium Institute, London, presented at the Randol Conference,Vancouver, 1998.8a measured resources of uranium, the amount known to beeconomically recoverable from ore bodies, are thus also relative to costsand prices. They are also dependent on the intensity of exploration effort.Changes in costs or prices, or further exploration, may alter measuredresource figures markedly. Thus, any predictions of the future availabilityof any mineral, including uranium and the fossil fuels mentioned earlier,which are based on current cost and price data and current geologicalknowledge are likely to be extremely conservative.8.5 Nuclear Electricity 7th Edition, 2003, available athttp://www.uic.com.au8.6 World Nuclear Association, available athttp://www.world-nuclear.org/info/reactors.htmlas of the 25th February 2003.8.7 International Energy Outlook 2002, Nuclear Power, pgs91-103,by the Energy Information Administration, available athttp://www.eia.doe/iea/as of 17th April 20038.8 G MacKerron, ‘Nuclear Power Under Review’, in The British Electricityexperiment: the Record, the Issues, the Lessons. London, UK:Earthscan Publications Limited, 1996) p159-160.8.9 Atoms Unleashed. Inside Science 157, New Scientist, 18th January 20038.10 The Energy Files: Gas, Understanding Energy, available athttp:/www.energy.co.uk/EFNuclear.html10.1 Michealis, Royal Society, Energy Mass Balance.10.2 UK Defra, Environmental Protection Statistics, available athttp://www.defra.gov.uk/environment/statistics/eiyp/inlwater10.3 Michealis, Royal Society, Energy Mass Balance.10.4 The Coal in Nitrogen report available athttp://www.acarp.com.au/Newsletters/nox.htmlas of the 17th January 2003.10.5 CA Lewis MEET Project: Methodologies for Estimating AirPollutant Emissions from Transport (ETSU 1995)12.1 Department of Trade and Industry Digest of United KingdomEnergy Statistics, The Stationery Office, 200112.2 The Future of CHP in the European Market - The European CogenerationStudy; Future Cogen Project; Report no XVii/4.1031/P/99-169, May 200112.3 Cogeneration in Germany; Cogeneration and On-site Power Production;Vol. 1 Issue 1, January-February 200012.4 The Future of CHP in the European Market -The European Cogeneration Study; Future Cogen Project;Report no XVii/4.1031/P/99-169, May 200112.5 http://www.re-focus.net/news/150103_1as of 31st Jan 200312.6 http://www.re-focus.net/news/220103_1as of 31st Jan 200312.7 http://www.re-focus.net/news/220103_3as of 31st Jan 200313.1 The Energy Saving Trust available athttp://www.est.org.ukas of 23rd June 200313.2 Alliance to Save Energy available athttp://www.ase.orgas of 23rd June 200313.3 National Renewable Energy Laboratory available athttp://www.nrel.gov/clean_energy/as of 20th June 200313.4 US Department of Energy,Energy Efficiency and Renewable Energy Programme, available athttp://www.eere.energy.govas of 23rd June, 200313.5 Energy Efficiency in the UK 1990-2000, March 2002 available athttp://www.dti.gov.uk/energyas of 23rd June 2003.14.1 Major Events in the Energy Industry; Annex D, available athttp://www.dti.gov.uk/energyas of 23rd June 2003.15.1 Energy White Paper available athttp://www.dti.gov.uk/energy/whitepaper/as of 23rd June 2003.15.2 Techno-Fixes Problematic Solutions: Are They Worth the Risk?Available athttp://www.globalwarming.enviroweb.org/dosomething/technofixes/as of 24th June 2003.8.11 Electricity Association Environmental Briefing Number 8,Radioactive Waste Management, revised September 1998.8.12 I Becqurel is a radioactivity level of one nuclear disintegration per second.8.13 World Nuclear Association, available athttp://www.world-nuclear.org/info as of the 25th February 2003.78

More magazines by this user
Similar magazines