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National Intergrated Resource Plan 2 - PBMR

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Contents<br />

Page<br />

FOREWORD 2<br />

ACKNOWLEDGEMENTS 3<br />

NIRP2 Reference Case Report 4<br />

NIRP2 Stage 2: Risk and Sensitivity Analyses Report 37<br />

NIRP2 Stage 2 Appendix A:<br />

Summary of Comments on NIRP2 Reference Case 65<br />

NIRP2 Stage 2 Appendix D:<br />

Summary of ARC Comments on NIRP2 Stage 2 report 76<br />

Information provided on CD ROM<br />

inside back cover<br />

NIRP2 Reference Case Appendix 1: Supply-side data,<br />

NIRP2 Reference Case Appendix 2: Results,<br />

NIRP2 Reference Case Appendix 3: Background supply-side data.<br />

NIRP2 Stage 2 Appendix B: Summary of <strong>Plan</strong>s<br />

NIRP2 Stage 2 Appendix C: NIRP2 Stage 2 Database


Foreword<br />

Background<br />

In the light of the Energy Policy White Paper for South Africa and the recent government initiatives for<br />

restructuring of the ESI, the NER introduced the development of a <strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> (NIRP)<br />

as an independent information source to stakeholders and decision-makers for insuring security of the supply.<br />

The first <strong>National</strong> IRP (NIRP1) was completed and published in March 2002.<br />

At the beginning of the year 2003, the NER established the NIRP Advisory and Review Committee (ARC) with<br />

the function to provide wide stakeholders' guidance and contribution to the NIRP development process.<br />

Unlike its predecessor the NIRP 2003/4 (NIRP2) relies on average international data (modified to reflect South<br />

African labor and exchange rates) for the cost and performance of new generation plants. Other important<br />

change from NIRP1 is the inclusion of sensitivity analysis and scenarios to address risk factors and<br />

uncertainties. Further the NIRP2 takes into account the transmission integration costs and losses associated<br />

with the location of the new generation plants.<br />

NIRP2 Studies<br />

2<br />

The NIRP2 has been generated under the guidance of the NER NIRP Advisory and Review Committee (ARC)<br />

by a NIRP team comprising Eskom <strong>Resource</strong>s and Strategy Group, Energy Research Institute of UCT and the<br />

NER. The work carried out for NIRP2 is divided into two stages:<br />

& Stage 1: Development of a reference case<br />

& Stage 2: Development of risk and sensitivity analyses<br />

The NIRP2 reference case was completed and published on the NER Web site on 3 March 2004 while NIRP2<br />

Stage 2: Risk and Sensitivity Analysis - on 22 September 2004.<br />

This publication consists of NIRP2 Stage 1 and 2 reports. Some of the Appendices associated with the main<br />

reports are provided in an electronic format (CD).<br />

The NIRP 2 Reference Case publication contains the following parts:<br />

& NIRP2 Reference Case Report<br />

& Appendix 1: Supply-side data<br />

& Appendix 2: Results<br />

& Appendix 3: Background supply-side data.<br />

The NIRP 2 Stage 2: Risk and Sensitivity analysis includes the following five parts:<br />

& NIRP2 Stage 2 Report,<br />

& Appendix A: Summary of comments on NIRP2 Reference Case<br />

& Appendix B: Summary of <strong>Plan</strong>s<br />

& Appendix C: NIRP2 Stage 2 Data Base Summary<br />

& Appendix D: Summary of ARC Comments on NIRP2 Stage 2 report.


Acknowledgements<br />

The NER acknowledge the guidance, contribution and<br />

valuable suggestions of:<br />

NER NIRP Advisory and Review Committee (ARC):<br />

Project Team:<br />

Chairman: Prof A Eberhard, NER Board<br />

Dr Bianka Belinska, NER<br />

Members: Smunda Mokoena, CEO NER Steve McFadzean, Eskom ISEP<br />

Naresh Singh, EM NER<br />

Johan Prinsloo, Eskom ISEP<br />

Andre Otto, DME<br />

Zaheer Khan, Eskom ISEP<br />

Dr Elsa Du Toit, DME<br />

Andrew Etzinger, Eskom ISEP<br />

Robert Maake, DME<br />

Mavo Solomon, Eskom ISEP<br />

Tseliso Magubela, DME<br />

Moonlight Mbatha, Eskom ISEP<br />

Chris Gadsden, NT<br />

Mark Howells, ERI UCT<br />

Justice Mavhungu, DPE<br />

Glen Heinrich, ERI UCT<br />

Arnot Hepburn, EIUG<br />

Thomas Alfstadt, ERI UCT<br />

Piet van Staden, EIUG<br />

Andrew Kenny, ERI UCT<br />

Dick Kruger, Chamber of Mines<br />

Alison Hughes, ERI UCT<br />

Danny Vengedasamy, SACOB<br />

Rizia Buckas, NER<br />

Manfred Kuster, AMEU<br />

Willie Boeije, NER<br />

Mandla Tshabalala, AMEF<br />

Lambert du Plessis, NER<br />

Gerhard Loedolff, Eskom Generation<br />

Lynette Vajeth, Eskom Generation<br />

WEB Publisher:<br />

June Willis, Eskom Transmission<br />

Michael Barry, Eskom Transmission<br />

Correy Sutherland, NER<br />

Segomoco Scheppers, Eskom Transmission<br />

Erica Johnson, Eskom Transmission<br />

NIRP Contact Person:<br />

Jean Louis Pabot, Eskom KSACS<br />

Hermann FW Oelsner, Darling Windfarm IPP<br />

Dr Bianka Belinska, NER<br />

Robert Siemers, Kelvin IPP Tel: 012-4014650<br />

Donald Bennett, Kelvin IPP Fax: 012-4014687<br />

Prof K Bennett, ERI UCT<br />

Email: bianka.belinska@ner.org.za<br />

3<br />

ARC Management Officer:<br />

Dr Bianka Belinska, NER


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Reference Case<br />

4<br />

COMPILED BY<br />

ISEP Eskom (<strong>Resource</strong>s and Strategy)<br />

AND<br />

Energy Research Institute<br />

University Of Cape Town<br />

AND<br />

The <strong>National</strong> Electricity Regulator<br />

27 February 2004


Reference Case<br />

Executive Summary<br />

INTRODUCTION<br />

In the light of the Energy Policy White Paper for South Africa and the recent government initiatives for<br />

restructuring of the ESI, the NER introduced the development of a <strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> (NIRP)<br />

as an independent information source to stakeholders and decision-makers for insuring security of the supply.<br />

The first <strong>National</strong> IRP (NIRP1) was completed and published in March 2002.<br />

At the beginning of the year 2003, the NER established an IRP Advisory and Review Committee (ARC) to<br />

provide wide stakeholders' contribution to the NIRP process. The main functions of the ARC are to approve the<br />

primary assumptions (technical, economical, environmental and social), evaluate the supply- and demand<br />

options for inclusion in the plan and oversee the development process.<br />

This NIRP is a revision of the first NIRP issued in March 2002 and published on the NER Web site. For the<br />

purposes of these analyses the first NIRP is referred as NIRP1 and the current study as NIRP2.<br />

The NIRP2 has been generated under the guidance and approval of the NER NIRP Advisory and Review<br />

Committee (ARC) by a NIRP team comprising Eskom <strong>Resource</strong>s and Strategy Group, Energy Research<br />

Institute of UCT and the NER.<br />

Unlike its predecessor the NIRP2 relies on average international data (modified to reflect South African labor<br />

and exchange rates) for the cost and performance of new generation plants.<br />

Other important change from NIRP1 is the inclusion of sensitivity analysis and scenarios to address risk<br />

factors and uncertainties such as performance of existing generation plants (Eskom and non-Eskom),<br />

sustainability and delivery of Demand-side Management (DSM) options (including Interruptible load supplies<br />

(ILS)) and changes in the electricity demand load shape. Further the NIRP2 takes into account Transmission<br />

integration costs and credit for regional location of new capacity not included previously.<br />

5<br />

The growth in demand for electricity over the next twenty-year planning horizon is consistent with that<br />

predicted in NIRP1 and follows a moderate forecast with moderate weather conditions.<br />

OBJECTIVE AND PRIMARY ASSUMPTIONS<br />

The objective of the <strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> (NIRP) is to determine the least cost supply options to<br />

the country, provide information to market participants on opportunities for investment in new power stations<br />

and evaluate the security of the supply.<br />

The NIRP2 reference case is based on the following primary assumptions approved by the ARC:<br />

& The net discount rate (before tax) agreed for the studies is 10 % internal to South Africa;<br />

& Options are compared on the basis of 1 January 2003 prices. Foreign capital is converted to South African<br />

Rand at the exchange rate of R9/$ reflective of a long-term planning approach;<br />

& <strong>Plan</strong>t availabilities for new plants are based on the World Energy Council (WEC) best quartile results for<br />

2002. For existing plants the studies use the current targets in Eskom adjusted independently for each<br />

individual station to give a weighted average for base-load capacity of 88% EAF; (7% PCLF: 3% UCLF with a<br />

provision of 2% for OCLF to cater for risk).<br />

& The planning horizon for the study is 20 years from 2003 to 2022;<br />

& Moderate electricity consumption and demand growth;<br />

& Low DSM penetration;<br />

& Inflation for all fuels and new technologies was at South African PPI.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

CAPACITY OUTLOOK FOR NIRP2 REFERENCE PLAN<br />

The capacity outlook for the NIRP Reference plan developed in Stage 1 is illustrated graphically in Figure 1.<br />

Reference capacity plan (10% Reserve margin) 2004 to 2022<br />

Capacity (MW)<br />

58000<br />

56000<br />

54000<br />

52000<br />

50000<br />

48000<br />

46000<br />

44000<br />

42000<br />

40000<br />

38000<br />

Greenfield <strong>PBMR</strong> (Base) - Earliest end 2013<br />

Greenfield PF (Base) - Earliest end 2013<br />

Greenfield Pumped Storage - Earliest 2013<br />

FBC (Base) - Earliest end 2009<br />

CCGT (Base) - Earliest end 2008<br />

Komati PF - Earliest 2010<br />

OCGT - Earliest 2008<br />

Grootvlei PF - 2007<br />

Camden<br />

36000<br />

Eskom Existing Capacity with Decommissioning Non-Eskom Existing Capacity with Decommissioning<br />

34000<br />

Imports-Cahora Bassa Hydro<br />

Simunye Eskom mothballed plants<br />

Pumped Storage capacity<br />

Peaking capacity<br />

32000<br />

Base load capacity Peak Demand before DSM<br />

Peak Demand after DSM<br />

Required capacity<br />

30000<br />

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

6<br />

Figure 1: Capacity Outlook for NIRP2 Reference <strong>Plan</strong><br />

CONCLUSIONS<br />

The main conclusions drawn from the NIRP2 reference case study could be summarised as follows:<br />

1) Options for diversification are insufficient to meet all of the forecast demand for electricity over the next 20-<br />

year planning horizon. Coal-fired options are still required for expansion during this period. For<br />

environmental benefit it is imperative to continue with efforts to reduce the costs of implementing clean<br />

coal technologies and improve the efficiency of coal-fired plants;<br />

2) Base load plants are required for commercial operation from 2010. Base load options competing, include;<br />

Pulverised Fuel Coal-fired (PF); Fluidised Bed Combustion (FBC); Combined Cycle Gas Turbine (CCGT).<br />

Given the cost and performance data used in the plan these options are broadly comparable, at 10% net<br />

discount rate, if regional siting and transmission benefits are included;<br />

3) At the current assumed cost of capital (10% net discount rate) and after returning the Eskom mothballed<br />

plant to service, fluidised bed combustion technologies are South Africa's most economic option, followed<br />

by investment in coal-fired plant. This in turn is followed by importing gas / LNG for CCGT plant in the<br />

Cape;<br />

4) It will be difficult to justify diversification on an economic basis, unless penalties for not doing so are<br />

included in future analyses. As the cost for diversification is becoming increasingly more expensive these<br />

penalties (or opportunities for emissions trading) will need to be substantial to offset the economic benefits<br />

of remaining with coal;<br />

5) The NIRP plans are based on attainment and sustainability of the DSM targets , power plants availability,<br />

imports and interruptible loads;<br />

6) The NIRP plans indicate that 920 MW OCGT peak load plants must begin commissioning from 2008;


Reference Case<br />

7) Maintaining a higher reserve margin of 15% over the planning period will require acceleration of the RTS of<br />

the mothballed plants and coal-fired options together with commissioning of additional base load capacity<br />

(CCGT);<br />

8) Diversified options are new technologies to South Africa. If these options for whatever reason are not able<br />

to be implemented it will mean a return to a dependency on new pulverised coal-fired plants earlier than<br />

shown in these plans;<br />

9) There are supply options that have not been considered such as co-generation in industry, converting<br />

OCGT to CCGT, adding units onto existing power stations and new imports resulting from the<br />

development of Electricity Supply in the Southern African region;<br />

10) Should interruptible supply and / or OCGT capacity not be implemented this will significantly advance new<br />

base-load capacity;<br />

7


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Table of Contents<br />

EXECUTIVE SUMMARY 5<br />

TABLE OF CONTENTS 8<br />

LIST OF TABLES 9<br />

LIST OF FIGURES 9<br />

ABBREVIATIONS 10<br />

1.INTRODUCTION - THE INTEGRATED RESOURCE PLANNING PROCESS 11<br />

2.STRATEGIC FRAMEWORK AND PRIMARY ASSUMPTIONS 11<br />

2.1 STRATEGIC POSITION (DEFINED BY THE ADVISORY AND REVIEW COMMITTEE (ARC)<br />

OF THE NER) 12<br />

2.2 PRIMARY ASSUMPTIONS 12<br />

2.3 RISKS AND UNCERTAINTIES 12<br />

2.4 OPTIMISATION PARAMETERS 13<br />

2.5 CRITERIA FOR INCLUSION OF SUPPLY-SIDE AND DEMAND-SIDE OPTIONS 13<br />

8<br />

3.NATIONAL ELECTRICITY FORECAST 13<br />

3.1 ECONOMIC GROWTH 16<br />

3.2 LARGE INDUSTRIAL PROJECTS 16<br />

3.3 ELECTRIFICATION 16<br />

3.4 ELECTRICITY INTENSITY 17<br />

3.5 NATURAL GAS 17<br />

3.6 FOREIGN FORECAST COMPONENT 17<br />

3.7 DEMAND PROFILES 18<br />

4.DEMAND-SIDE OPTIONS (DSM) 18<br />

4.1 THE DEMAND SIDE PLANNING BASIS FOR NIRP2 20<br />

4.2 INTRODUCTION TO THE DEMAND-SIDE SCREENING RESULTS 20<br />

4.2.1 Residential Energy Efficiency - REE 21<br />

4.2.2 Industrial, Mining and Commercial Energy Efficiency 22<br />

4.2.3 Residential Load Management (RLM) 23<br />

4.2.4 Industrial and Mining Load Management (IMLM) 23<br />

4.3 UNCERTAINTY AND RISK ASSOCIATED WITH DSM 23<br />

4.4 PRIORITIES FOR THE DEVELOPMENT OF DEMAND-SIDE RESOURCES 24<br />

5.SUPPLY-SIDE OPTIONS 25<br />

5.1 ESKOM SYSTEM - EXISTING AND COMMITTED CAPACITY 25<br />

5.2 NON-ESKOM SYSTEM - EXISTING CAPACITY 25<br />

5.3 RETURN TO SERVICE OF ESKOM MOTHBALLED PLANT (SIMUNYE) 25


Reference Case<br />

5.4 NEW SUPPLY-SIDE OPTIONS 26<br />

5.4.1 New Pulverised Fuel (PF) Coal-Fired Stations 26<br />

5.4.2 New Gas-Fired <strong>Plan</strong>t 26<br />

5.4.3 New Pumped Storage Schemes 27<br />

5.4.4 Greenfield Fluidised Bed Combustion 27<br />

5.4.5 Conventional Nuclear (Advanced Light Water Reactor (ALWR)) 29<br />

5.4.6 Research projects/programs 29<br />

5.4.7 Imported Hydro 29<br />

5.5 SCREENING CURVES 29<br />

5.6 OTHER: ENVIRONMENTAL, EXTERNALITIES, TRANSMISSION EXPANSION 31<br />

6.INTEGRATION AND SENSITIVITY ANALYSIS 31<br />

6.1 REFERENCE PLAN 32<br />

6.2 ALTERNATIVE PLAN 1 TO REFERENCE PLAN 33<br />

6.3 ALTERNATIVE PLAN 2 (SENSITIVITY STUDY) 33<br />

6.4 ALTERNATIVE PLAN 3 (OPTIMAL RESERVE MARGIN) 34<br />

7.SYSTEM ANNUAL AVERAGE LONG RUN MARGINAL COST 35<br />

8.CONCLUSIONS 36<br />

LIST OF TABLES<br />

Table 1: Average demand growth intervals 14<br />

Table 2: DSM aggregate megawatts displaced 19<br />

Table 3: Residential Energy Efficiency 21<br />

Table 4: Commercial energy efficiency 22<br />

Table 5: Industrial and Mining Energy Efficiency 22<br />

Table 6: Residential load management programmes 23<br />

Table 7: Industrial and mining load management 23<br />

Table 8: Summary of cost and performance data of new supply-side options 28<br />

9<br />

LIST OF FIGURES<br />

Figure 1: Electricity sales forecast range - <strong>National</strong> plus foreign 14<br />

Figure 2: Increase in annual peak demand and system losses (national plus foreign) 15<br />

Figure 3: Eskom track record 16<br />

Figure 4: RSA electricity intensity 17<br />

Figure 5: Typical hourly peak demand summer profile 18<br />

Figure 6: Typical hourly peak demand winter profile 18<br />

Figure 7: Life cycle levelised costs to build and operate base load plants 30<br />

Figure 8: Life cycle levelised costs to build and operate peaking plants 30<br />

Figure 9: Reference plan (10% Reserve Margin) 32<br />

Figure 10: Alternative 1 to reference plan (15% Reserve Margin) 33<br />

Figure 11: Alternative 2 - sensitivity to reference plan (excludes interruptible supply options) 34<br />

Figure 12: Annual average long run marginal costs of plans 35<br />

APPENDIX 1: SUPPLY SIDE MODELLING DATA SUMMARY<br />

APPENDIX 2: RESULTS<br />

APPENDIX 3: BACKGROUND SUPPLY SIDE DATA


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Abbreviations<br />

10<br />

ALWR<br />

ARC<br />

CEE<br />

CCGT<br />

CF<br />

CF (DSM)<br />

CV<br />

CUE<br />

DEAT<br />

DME<br />

DSM<br />

DWAF<br />

EAF<br />

EIA<br />

EPC<br />

ESI<br />

FBC<br />

FOR<br />

GT<br />

HELM<br />

HHV<br />

HTF<br />

ICLM<br />

IMEE<br />

IMLM<br />

IEA<br />

IRP<br />

ISEP<br />

LF<br />

LOLE<br />

LOLP<br />

LNG<br />

LPG<br />

MCR<br />

MEUL<br />

NDR<br />

MOU<br />

NER<br />

O&M<br />

OCGT<br />

OCLF<br />

PCLF<br />

<strong>PBMR</strong><br />

PF<br />

POR<br />

PPI<br />

PV<br />

PWR<br />

REE<br />

Advanced Light Water Reactor<br />

Advisory Review Committee<br />

Commercial Energy Efficiency<br />

Combined Cycle Gas Turbine<br />

Coal Fired<br />

Capacity Factor for DSM<br />

Calorific Value<br />

Cost of Unserved Energy<br />

Department of Environmental Affairs and Tourism<br />

Department of Minerals and Energy<br />

Demand Side Management<br />

Department of Water Affairs and Forestry<br />

Energy Availability Factor<br />

Energy Information Administration<br />

Engineering, Procurement and Construction<br />

Electricity Supply Industry<br />

Fluidised Bed Combustion<br />

Forced Outage Rate<br />

Gas Turbine<br />

Hourly Electricity Load Model<br />

High Heating Value<br />

Heat Transfer Fluid<br />

Industrial and Commercial Load Management<br />

Industrial and Mining Energy Efficiency<br />

Industrial and Mining Load Management<br />

International Energy Agency<br />

Integrated <strong>Resource</strong> <strong>Plan</strong><br />

Integrated Strategic Electricity <strong>Plan</strong>ning<br />

Load Factor<br />

Loss of load expectation<br />

Loss of load probability<br />

Liquefied Natural Gas<br />

Liquefied Petroleum Gas<br />

Maximum Continuous Rating<br />

Minimum Energy Utilization Level<br />

Net Discount Rate<br />

Memorandum of Understanding<br />

<strong>National</strong> Electricity Regulator<br />

Operation and Maintenance<br />

Open Cycle Gas Turbine<br />

Other Capability Loss Factor<br />

<strong>Plan</strong>ned Capability Loss Factor<br />

Pebble Bed Modular Reactor<br />

Pulverised Fuel<br />

<strong>Plan</strong>ned Outage Rate<br />

Producer Price Index<br />

Present Value<br />

Pressurised Water Reactor<br />

Residential Energy Efficiency<br />

RLM<br />

ROD<br />

UE<br />

UCLF<br />

WEC<br />

Residential Load Management<br />

Record of Decision<br />

Unserved energy<br />

Unplanned Capability Loss Factor<br />

World Energy Council


Reference Case<br />

1.INTRODUCTION THE INTEGRATED RESOURCE PLANNING PROCESS<br />

The prime objective of the <strong>National</strong> Integrated <strong>Resource</strong>s <strong>Plan</strong> (NIRP) is to provide a long-term least-cost<br />

resource plan for meeting the electricity demand consistent with the reliability of the electricity supply,<br />

environmental, social and economic policies. The NIRP also serves as an information tool for potential project<br />

developers and decision-makers.<br />

The NIRP provides an assessment of the system adequacy and also addresses other public policies such as<br />

environmental impacts and Demand Side Management (DSM).<br />

The NIRP also takes into account the “The New Partnership for African Development (NEPAD)” by<br />

incorporating committed contracts for imports and exports to South Africa from neighbouring States.<br />

This is the second NIRP carried out under the auspices of the NER. The first NIRP was carried out during 2001-<br />

2002 and published on the NER Web site. For the purposes of these analyses the first NIRP is referred as<br />

NIRP1 and the current study as NIRP2. This analysis follows the steps already defined in the NIRP 1 as<br />

follows:<br />

& Develop the primary assumptions and selection criteria;<br />

& Produce an electricity consumption and demand forecasts;<br />

& Investigate a full array of demand- and supply-side options and identify those that meet the strategic<br />

selection criteria for inclusion in the plan;<br />

& Determine an optimal combination of demand- and supply-side options from those selected for inclusion in<br />

the resource plan;<br />

& Evaluate the risk factors associated with uncertainties such as load growth, plant availability, weather<br />

conditions, DSM penetration level, level of interruptible loads etc;<br />

& Analyse the environmental, external and financial consequences;<br />

& Select a preferred plan.<br />

11<br />

The IRP studies carried out in this process use several computer software models. A major model is the RP<br />

Workstation, which consists of a suite of computer software programs, developed by the American Electricity<br />

Power Research Institute (EPRI) and specifically the optimisation module, Electric Generation Expansion<br />

Analysis System (EGEAS).<br />

Due to time constraints, the work carried out for this NIRP is divided into two stages as agreed within the terms<br />

of the <strong>National</strong> Electricity Regulator (NER) Advisory and Review Committee (ARC). These two stages consist:<br />

& Stage 1: Determine a reference plan for analysis and as basis for recommendation on capacity planning<br />

issues in the short-term;<br />

& Stage 2: Develop sensitivity studies and scenarios in order to address targeted risk factors and<br />

uncertainties.<br />

The first stage is intended for completion by Feb 2004, which constitutes this report, and the second for<br />

completion by April 2004.<br />

2.STRATEGIC FRAMEWORK AND PRIMARY ASSUMPTIONS<br />

This serves as the strategic basis for the planning assumptions for the NIRP. The NIRP2 was based on the<br />

planning assumptions approved by the ARC. These studies are based on January 2003 as its primary<br />

reference date for cost parameters and for the start of the twenty- year planning horizon. The NIRP is a longterm<br />

planning process and it is undertaken on an annual basis. The assumptions defined in this document<br />

need to be considered in that context.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

2.1 Strategic position (defined by the Advisory and Review Committee (ARC) of the NER)<br />

The following key points are worth highlighting:<br />

& The aim of the modelling is to determine the long-term least-cost electricity supply options to the country,<br />

independent of ESI structure and subject to the primary assumptions and constraints;<br />

& The NIRP includes the electricity market within and external to South Africa (imports to and exports from<br />

South Africa);<br />

& The NIRP may be used as a basis for identifying investment opportunities for suppliers in the ESI;<br />

& The NIRP's objective is to optimise the supply-side and demand-side mix to keep the price of electricity to the<br />

consumers as low as possible.<br />

2.2 Primary Assumptions<br />

The NIRP2 reference case is based on the following primary assumptions approved by the ARC:<br />

12<br />

& The net discount rate (before tax) agreed for the study is 10 % internal to South Africa;<br />

& Options are compared on the basis of 1 January 2003 prices. Foreign capital is converted to South African<br />

rands at the exchange rate of R9/$ reflective of a long-term planning approach;<br />

& <strong>Plan</strong>t availabilities for new plants are based on the World Energy Council (WEC) best quartile results for<br />

2002. For existing plants the studies use the current targets in Eskom adjusted independently for each<br />

individual station to give a weighted average for base-load capacity of 88% EAF; (7% PCLF: 3% UCLF with a<br />

provision of 2% for OCLF to cater for risk).<br />

& The planning horizon for the study is 20 years, from 2003 until 2022;<br />

& <strong>National</strong> moderate electricity consumption and demand growth;<br />

& Low DSM penetration;<br />

& Inflation for O&M and fuel resources at South African PPI unless stated otherwise;<br />

& New technologies costs are adjusted for Transmission integration or where applicable the avoided<br />

Transmission costs (and losses) according to regional site selection;<br />

& The NIRP2 does not make any assumptions on the ownership of the plants.<br />

2.3 Risks and Uncertainties<br />

This Report does not address risk rigorously but rather addresses it through imposing a minimum reserve<br />

margin on the plan of 10%. Imposing a deterministic reliability index (reserve margin of 10%) as a constraint<br />

does not directly reflect specific risk factors such as FOR, generation mix and unit size. However, it does<br />

provide a reasonable estimate of reliability performance when other parameters remain constant over the<br />

planning period.<br />

Due to time constraints, it was agreed at the ARC as a first pass, to develop a reference plan using a 10%<br />

reserve margin constraint as proxy for risk. The 10% reserve margin is reflective of current inter utility<br />

agreements in the Southern African Power Pool (SAPP). In addition, a second plan is developed based on a<br />

15% reserve margin constraint reflective of international practise.<br />

There are a large number of risks confronting the ESI in the future. These risks are both short-term and longterm.<br />

For example in terms of the load forecast a short-term risk could consist of an unexpected cold weather<br />

snap, whereas a long-term risk could be unexpected sustained increase in demand for electricity. Some of<br />

these risks include:<br />

& <strong>Plan</strong>t failure leading to longer than expected plant outage;<br />

& Unavailability of municipal / Eskom / imported generating capacity;<br />

& Degree of market penetration of DSM and maintaining current level of interruptible loads;


Reference Case<br />

& Unexpected decrease / increase, spurious or sustained, of electricity demand;<br />

& Changes to the load shape associated with the forecast electricity demand;<br />

& Unexpected decommissioning / de-rating of existing generating capacity<br />

& Uncertain and prolonged lead times for building new plant;<br />

& Project slippage<br />

& Inclusion of co-generation options;<br />

& Embargoes on nuclear energy;<br />

& Shortage of skills to maintain and grow the system;<br />

& Other energy forms displacing electricity in the energy market;<br />

& Revolutionary technologies coming on the scene and stranding existing assets;<br />

& Internalisation of externalities, such as Introduction of a carbon tax and environmental levy;<br />

& <strong>Plan</strong>t life expectations not met;<br />

& Retail choice;<br />

& Deterioration in credit rating, exchange rates etc. resulting in a higher cost of capital;<br />

& Electricity supply and sales contracts (import and export contracts) being reneged upon;<br />

& Effect of AIDS on the electricity market.<br />

& Drought and Floods<br />

2.4 Optimisation parameters<br />

The basis for the optimisation of this NIRP is the least cost of electricity for the supply life cycle. This takes into<br />

consideration the cost of un-served energy (CUE) to the consumer. For this NIRP2, the CUE is assumed to be<br />

R20 666/MWh (Eskom 2003).<br />

This CUE was derived from a customer survey of the market sectors of the electricity supply industry (ESI).<br />

Because of an expected marketing drive for DSM, mainly in the residential sector, but also in the commercial<br />

and industrial sectors, the high CUE associated with the industrial sector was chosen as representative. This is<br />

because DSM initiatives that could change the load profile may become exhausted over the 20-year planning<br />

horizon. Previous NIRP1 used CUE of R 19000/MWh associated with the industrial sector.<br />

13<br />

2.5 Criteria for inclusion of Supply-side and Demand-side options<br />

The criteria listed below have been approved by the NER's Advisory and Review Committee (ARC) and are<br />

intended to give guidance in determining whether an option is formally included in the base case.<br />

Technologies that are not included in the base case will be evaluated in sensitivity studies. For technologies to<br />

be included in the reference case they should:<br />

& Be technologically feasible;<br />

& Be economically viable;<br />

& Have adequate accuracy of costs;<br />

& Be under national control either via equity participation, ownership or secure contracts;<br />

& Be socially, politically and environmentally acceptable;<br />

& Be dispatchable;<br />

& In line with World Bank emission standards.<br />

3.NATIONAL ELECTRICITY FORECAST<br />

The load forecast is the foundation upon which resources planning is based. It is an endeavour to forecast the<br />

most likely futures based on selected long-term Southern African economic forecasts. The forecast takes as its<br />

starting point the current position in the electricity supply market but in projecting the future, it excludes any<br />

further demand-side interventions.<br />

A detailed sectoral approach has been used over the last ten years to develop the long-term energy (GWh)


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

forecast. This method has been improved and refined over time. Using a sectoral approach, which considers<br />

about 110 sectors or major customers individually, is one of the ways to lower the forecast risk. The forecast<br />

has also been updated on average more than once per year during the past ten years.<br />

The national plus foreign electricity forecast used in these studies is based on an average annual economic<br />

growth rate of 2.8%, over the planning horizon and moderate temperatures throughout the year. The foreign<br />

portion includes normal sales to traditional neighbouring states plus the Scorpion zinc project in Namibia and<br />

the aluminium smelters Mozal 1 & 2 in Mozambique.<br />

To address the major inherent uncertainty in the environment, a cone of uncertainty approach is used to<br />

develop low, moderate and high-energy forecasts. The electricity database consists of the best quality of data<br />

for all the 110 individual sectors, going back as far as 1980. The load forecast has been developed by Eskom<br />

together with contributions from major sectors/customers and wide consultations inside and outside Eskom.<br />

The <strong>National</strong> forecast range is illustrated in Figure 1 below.<br />

Electricity sales forecasts - national plus foreign<br />

400000<br />

350000<br />

High<br />

Moderate<br />

Low<br />

14<br />

GWh<br />

300000<br />

250000<br />

200000<br />

150000<br />

2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022<br />

Figure 1: Electricity sales forecast range - <strong>National</strong> plus foreign<br />

The average growth in energy in intervals over a five-year period within the planning horizon is given in Table 1:<br />

Table 1: Average demand growth intervals<br />

High (%) Moderate (%) Low (%)<br />

2003 - 2008 4.3 3.2 1.6<br />

2008 - 2013 3.1 2.3 1.0<br />

2013 - 2018 2.6 1.8 0.9<br />

2018 - 2022 2.5 1.8 0.8<br />

The electricity growth in the early years until 2006 is high (4% pa) due in part to cater for major expansions in<br />

platinum mining and high demand for ferrochrome as experienced in 2002 and 2003 and one further 850MW<br />

aluminium smelter at Coega. However this high growth is not sustained after 2006. Eskom sales growth has<br />

been high in 2002 and 2003 but the average sales growth is only 2.2% per annum over the last six years. The<br />

long-term forecast allows for a growth in fixed investment but there are currently no new major projects, which<br />

have been officially approved, other than the platinum mine expansions.


Reference Case<br />

An hourly electricity load model (HELM) is used to develop the maximum demand forecast where the annual<br />

energy forecast has been converted to an annual maximum demand forecast using updated sectoral<br />

customer usage profiles. It is expected that system energy utilisation with respect to annual peak demand will<br />

deteriorate slightly over time and the system annual load factor worsen from a current average of 74% to about<br />

73% by 2017.<br />

Of specific importance is the impact of system losses on the forecast demand. The Eskom system losses have<br />

been increasing over the last number of years from 5% in 1990 to 7.7% in 2002. The system losses for the<br />

<strong>National</strong> forecast are estimated to be currently 9% increasing to in excess of 10% over the planning horizon.<br />

Details of the moderate annual forecast (energy and demand) are shown in the Tables given in Appendix 2 to<br />

this report. The demand forecast is illustrated in Figure 2: Increase in annual peak demand and system losses<br />

(national plus foreign) below.<br />

Increase in forecast annual peak demand (<strong>National</strong> + Foreign) and losses<br />

12.0%<br />

10.0%<br />

(%) Increase<br />

8.0%<br />

6.0%<br />

4.0%<br />

<strong>National</strong> + Foreign annual<br />

system losses (%)<br />

Annual Increase in peak<br />

Demand (<strong>National</strong> + Foreign) (%)<br />

Forecast Annual Peak Demand in<br />

2022 = 53256MW<br />

I e. Growth from 2004 to 2022 =<br />

19611MW<br />

15<br />

2.0%<br />

Forecast Annual<br />

Peak Demand in<br />

2004 = 33645MW<br />

0.0%<br />

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

Figure 2: Increase in annual peak demand and system losses (national plus foreign)<br />

The short-term accuracy of the forecast and the track record of the long-term forecast are being monitored on<br />

an annual basis. The short-term variance is around the zero line and is not always positive or always negative.<br />

Figure 3 below tracks Eskom's (as opposed to national plus foreign) forecast predictions over the last ten years<br />

within a cone of 1.5% to 4% growth per annum. Actual sales are shown in the thick black line.<br />

Over the last few years these results show that the actual values achieved were slightly lower than the forecast<br />

values but in the last two years actual values were slightly higher. It is also important to note that the forecast<br />

value for the year 2007, as seen at this stage is very close to the value forecasted for the same year in 1996.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Eskom long term sales forecast track record<br />

GWh<br />

370000<br />

320000<br />

270000<br />

220000<br />

1994<br />

1995<br />

1996<br />

1997<br />

1998<br />

1999<br />

2000<br />

2001<br />

2002<br />

2003<br />

Actual<br />

High 4%<br />

Low 1.5%<br />

170000<br />

120000<br />

1990 1995 2000 2005 2010 2015<br />

16<br />

Figure 3: Eskom track record<br />

The following is a brief summary of the main assumptions of the long-term forecast (national plus foreign).<br />

3.1 Economic Growth<br />

Long term economic growth rate for the moderate forecast is 2.8% average annual growth over the planning<br />

horizon. This economic growth rate takes into account the impact of HIV / AIDS.<br />

3.2 Large Industrial Projects<br />

New large industrial projects, such as the proposed Pechiney aluminium smelter, Billiton Hillside aluminium<br />

smelter expansions, Columbus Stainless Steel expansions, Sasol new projects and expansions and Mozal 2,<br />

have been included in the forecast. Further expansions to ferrochrome plants are also provided for. Current<br />

platinum mining expansions have been included, with provision for limited expansions after 2007/8. It was<br />

assumed that new gold mining projects would replace old ones. Gold production in South Africa is assumed to<br />

continue to decrease slightly over the long term. With regard to the longer term, allowance had also been made<br />

in the energy forecast for unknown new projects, based on past experience. A list is regularly revised for all<br />

possible new electricity intensive projects, including projects with a very low probability of occurrence.<br />

3.3 Electrification<br />

The forecast makes provision for the electrification of homes by Eskom and the municipalities. Electrification<br />

carried out by Eskom forms the bulk of its prepaid sales category. The number of connections obtained from<br />

planners and an estimated consumption per connection are used as a guide. It is assumed that the<br />

electrification rate will level off over time. The prepaid category only formed about 2.5% of total 2002 electricity<br />

sales in the country.


Reference Case<br />

3.4 Electricity Intensity<br />

The growth in the long term forecast is high in the near term due to major expansions of some electricity<br />

intensive industries. However, the growth is expected to reduce in the latter period of the planning horizon due<br />

to the fact that the electricity intensity of the South African economy is expected to decrease over time. This is<br />

characteristic of an economy, which is moving towards a more service based structure as is the case in South<br />

Africa and implies that the GDP growth rate in future will be consistently higher on average than the electricity<br />

growth rate. This has already been experienced in South Africa during the four-year period 1998 to 2001.<br />

The electricity intensity of the South African economy is shown in Figure 4. The current major expansions of<br />

electricity intensive industries are expected to decline and platinum mining is not expected to continue to<br />

maintain the current high growth rates after 2007/8. With more beneficiation of minerals, less energy will be<br />

required per unit of production. Once there is no more excess generating capacity, electricity prices will have to<br />

increase in real terms. Although it is assumed that this increase will not be extraordinary, it is expected that it<br />

will marginally affect electricity consumption.<br />

0.35<br />

RSA electricity intensity<br />

0.30<br />

0.25<br />

kWh / rand<br />

0.20<br />

0.15<br />

17<br />

0.10<br />

0.05<br />

0.00<br />

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000<br />

Figure 4: RSA electricity intensity<br />

3.5 Natural Gas<br />

Allowance is made for the loss in electricity sales due to consumers switching from the use of electricity to the<br />

use of natural gas.<br />

3.6 Foreign Forecast component<br />

This part of the forecast includes sales that are currently in place - mostly under contract. Also included are the<br />

Mozal aluminium smelter in Mozambique and the Skorpion zinc project in Namibia. Provision had also been<br />

made for the Corridor heavy mineral sands project in Mozambique over the longer term.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

3.7 Demand Profiles<br />

Figure 5 shows a typical demand profile for the total Eskom system for a summer week.<br />

27000<br />

25000<br />

Eskom integrated system typical summer week hourly demand profile<br />

January/February<br />

2002<br />

2001<br />

2000<br />

23000<br />

MW<br />

21000<br />

19000<br />

17000<br />

15000<br />

Mon Tue Wed Thu Fri Sat Sun<br />

Figure 5: Typical hourly peak demand summer profile<br />

Figure 6 and shows a typical demand profile for the total Eskom system for a winter week.<br />

18<br />

33000<br />

31000<br />

29000<br />

27000<br />

Eskom integrated system typical winter week hourly peak demand<br />

July<br />

2002<br />

2001<br />

2000<br />

MW<br />

25000<br />

23000<br />

21000<br />

19000<br />

17000<br />

15000<br />

Mon Tue Wed Thu Fri Sat Sun<br />

Figure 6: Typical hourly peak demand winter profile<br />

4.DEMAND-SIDE OPTIONS (DSM)<br />

This NIRP2 assumes a significantly (approximately 50%) lower penetration of DSM programmes than the<br />

previously in NIRP1. Previous estimates were based on desktop studies. Pilots and experience in the field<br />

now indicate that a more conservative approach should be followed in the estimates for DSM programmes<br />

both in terms of capacity and cost. Five DSM programmes are targeted:


Reference Case<br />

& Residential Energy Efficiency (REE)<br />

& Commercial Energy Efficiency (CEE)<br />

& Industrial and Mining Efficiency (IMEE)<br />

& Residential Load Management (RLM)<br />

& Industrial and Mining Load Management (IMLM)<br />

Each programme has been modelled on a basis that capital will be expended over a nine-year period to ensure<br />

increasing annual displacements of aggregate Megawatts will be deducted from the load associated with a<br />

specified energy usage profile as indicated in the Table 2.<br />

Table 2: DSM aggregate megawatts displaced<br />

Programme Annual MW Displacements Annual Energy Displaced GWh<br />

Residential Energy Efficiency 32 129<br />

Commercial Energy Efficiency 14 69<br />

Industrial and Mining Efficiency 16 101<br />

Residential Load Management 49<br />

Industrial and Mining Load Management 41<br />

Each aggregate annual displacement is maintained over a period of twenty years to ensure no deterioration of<br />

displacement takes place. (I.e. maintenance will continue for a further 11 years beyond the nine-year<br />

investment period).<br />

Interruptible supply options are modelled separately to the above DSM programmes. Eskom has several<br />

interruptible supply agreements with key customers. These agreements are severely energy constrained and<br />

their capacity impact in the long-term has been reduced. There have been several comments by various ARC<br />

members to consider these interruptible supply agreements as emergency capacity only. This issue will be<br />

addressed in the next round of the NIRP in terms of the uncertainty inherent in this assumption.<br />

19<br />

The DSM team of Eskom in their endeavours to continually improve decision-making on the role of DSM in<br />

resources planning have taken several actions one of which is to improve information on DSM before its<br />

inclusion.<br />

In terms of residential DSM, Eskom has good statistics on device populations and unit gains in the residential<br />

markets. The homogeneity in residential markets provides confidence in DSM planning data, because enduse<br />

devices are generally characterised within narrow ranges of diversity.<br />

The need to upgrade confidence for this NIRP was in the commercial and industrial market segments,<br />

because previously there was no sound strategy to deal with the diversity of information. Fortunately since the<br />

previous <strong>National</strong> Integrated <strong>Resource</strong>s <strong>Plan</strong>, NIRP1, the DSM team has had access to a document on market<br />

assessment for electric motors prepared for the Department of Energy (DOE) in the USA. This document<br />

clearly spells out the opportunities for energy efficiency in the majority of the commercial and industrial enduse<br />

sectors. Electric motors make up nearly 50% of Eskom's total sales, or more than 65% of the sales to<br />

industrial and commercial clients.<br />

A major task in preparation of DSM data for NIRP2 has been the mapping of the DOE information on DSM<br />

opportunities in the USA into the South African context. This has now been done, and together with other desk<br />

research it has been revealed that the situation in SA is very different to the USA. South Africa needs to devise<br />

its own strategy to contend with issues that do not exist in the case of the USA.<br />

There has been a major focus on the industrial and commercial sectors, providing a better insight into the CEE,<br />

IMEE and IMLM strategies to be adopted in the future. A further improvement in this NIRP is in the provision of


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

an aggregated summary for the ICEE and ICLM programmes compared with the previous industrial and<br />

commercial components.<br />

The NIRP1 placed more emphasis on energy efficiency as opposed to load management programmes. Better<br />

experience has now shown this emphasis to be misplaced, in that energy efficiency programmes are difficult to<br />

implement and to achieve performance targets due to the many barriers involved, and are turning out more<br />

costly than previously estimated.<br />

4.1 The Demand Side <strong>Plan</strong>ning Basis for NIRP2<br />

The basis for end-use load forecasting adopted for DSM planning in this NIRP is the “moderate forecast” as<br />

detailed above. The amount of DSM resources to be developed over a planning period is very sensitive to the<br />

load forecast. For sensitivity studies there is also the facility to use a “high load growth” and a “low load growth”<br />

forecast. A high growth forecast would imply higher targets for DSM, and a low load forecast would suggest<br />

lower targets than required for the moderate forecast. This issue will also be addressed in the next round of the<br />

NIRP in terms of the uncertainty in DSM penetration.<br />

4.2 Introduction to the Demand-Side Screening Results<br />

The following summarises the DSM resources submitted for inclusion in the NIRP2. <strong>Resource</strong>s that are not<br />

currently included may qualify for inclusion in future version if further investigation provides the information<br />

needed to obtain positive screening results. The screening results for energy efficiency options are given in<br />

Table 1 to 3 below. For comparison, separate columns give the NIRP1 and NIRP2 assumed market<br />

penetration.<br />

20<br />

In Tables 6 and 7, pertaining to the load management resources, there are high and low capacity factor (CF)<br />

resource capacities, given in MW, and the balance, which is the difference between the two.<br />

Capacity factor is defined as the percentage of time that the capacity of the load management resource can be<br />

fully utilised. “Hi CF MW” means that control algorithms are utilised to achieve a high capacity factor. There is a<br />

maximum percentage of time that the residential load management (RLM) resource can be utilised. In the<br />

maximum percentage mode the system peak MW can only be reduced by the amount reflected in the “Hi CF<br />

MW” column.<br />

The system peak can be further reduced by the amount in the “Balance of MW” column, when operated in the<br />

low capacity mode. The “Lo CF MW” column indicates the total reduction of the system peak if the entire load<br />

management resource is only operated in low capacity factor mode.


Reference Case<br />

4.2.1 Residential Energy Efficiency - REE<br />

Table 3 gives the results of screening Residential Energy Efficiency.<br />

Table 3: Residential Energy Efficiency<br />

OPTION No of units Assumed Market<br />

Penetration<br />

MW/a GWh/a IN NIRP2 NIRP1 NIRP2<br />

INTEGRAL CFL'S 25.20 91.97 YES 33% 20%<br />

HOT WATER SYS. EFFICIENCY 2.93 10.13 YES 28% 10%<br />

LOW FLOW SHOWERHEADS 2.38 8.22 YES 34% 10%<br />

HOTWATER CONSERVATION 0.47 1.63 YES 30% 10%<br />

COOKING AWARENESS 1.34 3.44 YES 30% 10%<br />

EFFICIENT COOL STORAGE NO 30% 10%<br />

THERMAL EFFICIENCY NO 30% 10%<br />

DEMARKETING TO GAS NO 30% 15%<br />

MODULAR CFL'S NO 33% 20%<br />

Total 32.39 129.0<br />

The REE resources submitted for NIRP are predominated by integral CFL's.<br />

The energy efficiency measures related to hot water systems have also been included but it was decided not to<br />

include efficient cool storage appliances, thermally efficient building practices and de-marketing to gas. Also<br />

included are integral CFL's and energy efficiency measures on storage water heaters. The integral version of<br />

the CFL costs less to sustain this technology over the planning period. The major problem associated with<br />

targeting integral CFL's for the efficient residential lighting initiatives is the risk of sustainability (i.e. conversion<br />

back to inefficient incandescent light bulbs in the future).<br />

21<br />

The strategy with respect to electrical water heating is to encourage storage water heating. Indications are that<br />

residential load management is a lower cost resource than building peaking plant. Instant water heaters have<br />

not found favour, because they do not lend themselves to load shifting. For storage water heating to hold its<br />

ground in SA it is important to demonstrate that these systems can be energy efficient, and that the per capita<br />

water consumption can be contained, especially in the event of water shortages at a future time. For waterheater<br />

system efficiency measures like hot water conservation, low flow showerheads and thermal insulation<br />

are included.<br />

Other DSM options that have been included in residential energy efficiency strategies in other countries have<br />

yet to be developed to a stage where they are mature enough to include in the REE strategy with some<br />

confidence. For example energy-efficient fridges and freezers will only be included in the strategy at a later<br />

stage when there is more clarification on appliance labelling policy. Information is required on how appliance<br />

labelling would help to create demand and to make the program economically more attractive. The strategy on<br />

fridges and freezers is therefore to closely monitor the DME initiatives regarding appliance labelling.<br />

Residential space-heating loads are not included but should be targeted as a demand-side measure, because<br />

they are one of the main reasons for poor utilization of supply capacity, and therefore not very economical to<br />

supply. Previous work by the DSM team has indicated that gas heating is likely to be more expensive to the<br />

consumer, yet electrical space heating is losing market share to gas space heating. With rising oil prices, and<br />

therefore LPG prices, it is uncertain, whether there will be a significant shift to gas for space heating. Better<br />

information is needed on how thermal efficiency measures impact on space heating demand before deciding<br />

on a relevant strategy. In particular, there is a need to know what the most marketable measures are to desensitise<br />

system space-heating demand to weather-related events like falling temperatures and cloud cover<br />

during winter months.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

4.2.2 Industrial, Mining and Commercial Energy Efficiency<br />

Table 4 gives the results of screening CEE programmes. For CEE, the assumptions on market penetration<br />

remain more or less the same as with the NIRP1<br />

Table 4: Commercial energy efficiency<br />

OPTION No of units Assumed Market<br />

Penetration<br />

MW/a GWh/a IN NIRP2 NIRP1 NIRP2<br />

SUPERVISION 2.05 10.60 YES 14.1% 15%<br />

FANS/PUMPS 0.64 4.68 YES 26.0% 26.0%<br />

COMP AIR<br />

LIGHTING 9.53 43.54 YES 27.0% 27.0%<br />

VSD's 0.26 1.90 YES 3.0% 3.0%<br />

REPLACE 0.68 3.50 YES 15.0% 10.0%<br />

UPGRADE 0.66 3.40 YES 13.0% 10.0%<br />

DOWNSIZE NO<br />

COOLING SYSTEM EFF NO<br />

HEAT RECOVERY NO<br />

INSULATION NO<br />

Total 13.82 69.38<br />

22<br />

Table 5 gives the results of screening of Industrial and Mining energy efficiency programmes<br />

Table 5: Industrial and Mining Energy Efficiency<br />

OPTION No of units Assumed Market<br />

Penetration<br />

MW/a GWh/a IN NIRP NIRP1 NIRP2<br />

SUPERVISION 2.24 15.33 YES 14.1% 2.0%<br />

FANS/PUMPS 1.31 9.26 YES 26.0% 5.0%<br />

COMP AIR 2.26 16.54 5.0%<br />

LIGHTING 3.77 23.44 YES 27.0% 10.0%<br />

VSD's 4.40 29.3 YES 3.0% 3.0%<br />

REPLACE 1.13 7.72 YES 15.0% 2.0%<br />

UPGRADE 1.06 7.02 YES 13.0% 2.0%<br />

DOWNSIZE NO<br />

COOLING SYSTEM EFF NO<br />

HEAT RECOVERY NO<br />

INSULATION NO<br />

Total 16.15 100.93<br />

These results suggest that most of the drive-power programs qualify for submission. The demand-side plan<br />

assumes that ESCO's will be enabled that specialize in the delivery of CEE and IMEE resources to the<br />

industrial market, and that they are competitive and operational in SA in the future. Under these assumptions it<br />

is possible that this target can be achieved within 10 years.<br />

This assumption assumes support from<br />

governance authorities in terms of policy.<br />

Additional energy efficiency resources would become available were commercial and industrial participants to


Reference Case<br />

focus their attention on heating and cooling systems that derive their energy from an electricity supply. These<br />

are indicated in the demand-side plan as a requirement for further investigation.<br />

The most viable area for industrial and commercial energy efficiency is motor supervision and control.<br />

Maintenance and supervision of compressed air or gas compressor systems is another area for potentially<br />

very cost-effective energy efficiency measures. Companies that employ the practice of re-winding motors<br />

rated lower than 45kW may require advice on the economics of re-winding versus replacing. In some cases it<br />

may even pay to upgrade motors to premium efficiency motors.<br />

It is most important to transform the market for new construction to energy efficient lighting, especially in<br />

commercial buildings. Lighting controls should be installed to avoid unnecessary lighting usage. Retrofits<br />

typically do not offer very short paybacks, but are in the range where respectable rates of return can be<br />

guaranteed. Lighting retrofits that would also reduce air-conditioning load should be targeted first. It is a matter<br />

of major concern that the majority of industrial and commercial lighting sales into the new construction market<br />

still conform to old and outdated standards for energy efficiency.<br />

Every effort should be made to apply best practices in the design of systems employing fluid or airflow. In<br />

particular excessive throttling of flow should give way to variable speed drives or staged switching of drives,<br />

and pipes and ducts should be sized to minimise total resource costs. Every effort should be made to promote<br />

the adherence to best practices on systems with pumps, fans and compressors. CEE and IMEE retrofits<br />

should initially target systems of large drives, i.e. 200 kW and larger.<br />

4.2.3 Residential Load Management (RLM)<br />

In the case of RLM, the screening criteria have led the DSM Team to firm conclusions on the RLM strategy. Up<br />

until now too many conflicting DSM strategies were considered. Table 6 gives the results of screening the<br />

various RLM strategies and options.<br />

23<br />

Table 6: Residential load management programmes<br />

SUMMARY OF RLM SCREENING RESULTS<br />

Options Hi CF MW/a Balance of MW/a Lo CF MW/a<br />

Ripple Control 49 49 98<br />

4.2.4 Industrial and Mining Load Management (IMLM)<br />

The pre-integration study data shows that for IMLM there is a potential 600 MW of controllable load that can be<br />

developed, assuming the resource is operated at high capacity factor.<br />

A summary of the first-round screening results for ICLM is given in Table 7<br />

Table 7: Industrial and mining load management<br />

Options Hi CF MW/a Balance of MW/a Lo CF MW/a<br />

INDUSTRIAL/ MINING LOAD 40.9 40.9 82<br />

Under system emergencies the resource can be operated at low capacity factor. The low capacity factor<br />

figures assume that the resource is required for 2 hours per day.<br />

4.3 Uncertainty and Risk Associated with DSM<br />

The DSM team has had to come to grips with the reality that it is developing DSM plans for a fast-changing<br />

energy market. Many of the decisions about the future structures of the Electricity Supply Industry (ESI) in


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

South Africa, which have yet to be made, may impact on DSM. Utilities will have no control over the way the<br />

industry will develop in future.<br />

To deal with uncertainty about the future, the DSM team has to make certain assumptions regarding the<br />

conditions for sustainable demand-side resources to exist. The DSM programmes assume that the<br />

governance authorities in consensus will set up the specified conditions for a DSM resource market with key<br />

stakeholders and energy consumers.<br />

Risk is closely linked to a lack of dependable information. The Demand-side plans make many assumptions on<br />

important factors that affect market penetration. The DSM assumptions and resource plans are based on<br />

targets that are believed to be realistic. The demand-side plan is exposed to risk if any of the assumptions are<br />

proven to be unrealistic. It is prudent to firm up on much needed information about the market potential for<br />

demand-side resources.<br />

4.4 Priorities for the Development of Demand-Side <strong>Resource</strong>s<br />

24<br />

These demand-side plans are based on the assumption that the SA market will be willing and able to transform<br />

towards a preference for the development of demand-side resources. Historically the preference has been to<br />

develop supply-side resources, so the SA market is currently not richly endowed with the resources and skills<br />

required to deliver demand-side resources on a large scale. A prime issue of concern is the fact that DSM is<br />

often seen from a utility perspective as a loss leader in that their core business is in selling electricity. This is<br />

especially relevant to energy efficiency programmes and it is imperative that policy and legislation be adopted<br />

in future to address this problem. Another major problem is in sustainability. For example in the Table View load<br />

management pilot study, previously about 8-10MW could be achieved through geyser control. Recent tests<br />

show only 4MW can currently be switched off. Customers are bypassing the system because they see no<br />

personal benefit as no time-of-use tariff is in place for individual residential customers.


Reference Case<br />

5.SUPPLY-SIDE OPTIONS<br />

Technology options are compared on the basis of discounted cash flows (total capital & operating costs) over<br />

the option lifetime using 10% net discount rate as dictated by the ARC of the NER. The levelised cost per unit<br />

output of the option is obtained by dividing the present value by the total discounted lifetime generation.<br />

Levelised costs are calculated as a function of plant load factors (screening curves) to illustrate the relation<br />

between the levelised cost and plant load factor.<br />

5.1 Eskom System - Existing and Committed Capacity<br />

The current (2003) total net base load capacity in operation of the Eskom system is given in Appendix 1 to this<br />

report and is 33 871 MWe. The total net peaking capacity in operation is 2319 MWe. This includes Acacia and<br />

Port Rex gas turbines, Drakensberg and Palmiet pumped storage, Gariep and Vanderkloof hydro plants.<br />

Eskom has a long-term contract to purchase power from Cahora Bassa hydro plant in Mozambique. Available<br />

net capacity from Cahora Bassa is at present 912 MWe (after losses). A further 369 MWe (after losses) is<br />

committed from 2004. Eskom is importing about 100 MWe of peaking capacity from Zesco (Zambia) via<br />

Zimbabwe and about 110 MWe from the DRC. These latter are excluded from the study as Eskom has been a<br />

net exporter of similar proportions to neighbouring states. (I.e. as these imports and exports are effectively<br />

equivalent the exports are not included in the load forecast nor are the imports included in the capacity plan).<br />

5.2 Non-Eskom System - Existing Capacity<br />

The following options are considered in the plan:<br />

Appendix 1 also gives the net capacity of non-Eskom generating plant. These have been aggregated into<br />

blocks of similar capacity units for modelling purposes as follows:<br />

25<br />

& Munic 1: consisting 12x60 MW sent out coal-fired capacity<br />

& Munic 2: consisting 21x30 MW sent out coal-fired capacity<br />

& Sasol: consisting 12x60 MW sent out coal-fired capacity<br />

& Steenbras pumped storage plant: 3x60 MW sent out<br />

& Mini Hydro: 1x65 MW sent out<br />

& Minic OCGT: 6x50 MW sent out<br />

The details of these plant and capacities are given in Appendix 1.<br />

In addition to the Eskom and non-Eskom supply capacity there is a total 1510 MW interruptible supply capacity<br />

included in the plan. The interruptible load accepted for inclusion in the plan, although based on current<br />

contracts, does not necessarily represent the existing contracts. It is assumed that some level of interruptible<br />

capacity, either in the form of contracts for reserve or as a demand-side bidding option, will exist in the future. In<br />

total the existing capacity assumed on the <strong>National</strong> system in 2003 amounts to 41378 MWe sent out.<br />

5.3 Return to Service of Eskom Mothballed <strong>Plan</strong>t (Simunye)<br />

These are the stations that were put into storage during the period of high excess capacity on the Eskom<br />

system: Camden (1520 MW), Grootvlei (1130 MW) and Komati (909 MW). These capacities are on a sent out<br />

basis. These stations all use PF coal. When refurbished, Camden is anticipated to run as base load, whereas<br />

Grootvlei and Komati would most probably be two-shifted i.e. operating at an annual load factor of less than<br />

30%.<br />

Results of a pre-feasibility study initiated and carried out by Eskom indicate that repowering some of Eskom's<br />

old plant with Fluidised Bed Combustion (FBC) technology (such as at Komati) could be an option in


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

comparison with other future base load plant. The remaining half of Komati (456 MW) could be re-powered<br />

with FBC technology to operate as base load.<br />

5.4 New Supply-Side Options<br />

Table 8 below summarises the data for all the new supply-side technologies considered in the plan. Detailed<br />

description of the cost and performance of the considered supply-side options is shown in Appendix 3. The<br />

ARC, applying the approved selection criteria, determined the inclusion of the supply side technologies in the<br />

plan. The capital costs are averages of the international data evaluated. Operating and Maintenance costs<br />

shown are averages from the international literature, after they have been adjusted for South African labour<br />

conditions. Appendix 3 contains additional information about the supply-side technologies, including costs,<br />

performance parameters, lead times and data statistics.<br />

A transmission benefit has been given to stations built in the Cape close to the load centres. This is to account<br />

for the line losses that occur when transmitting electricity from an equivalent station in the Highveld and for<br />

strengthening the grid along transmission lines.<br />

<strong>PBMR</strong> data is given for both the initial multi-module and, after several multi-modules have been deployed, a<br />

cheaper multi-module (costs are likely to decrease, benefiting from technology learning).<br />

Adding units to existing coal plants and co-generation options have not been considered in the plan.<br />

5.4.1 New Pulverised Fuel (PF) Coal-Fired Stations<br />

26<br />

In the absence of more cost competitive options, coal-fired plants are likely to remain the backbone of the<br />

electricity supply industry in South Africa for a long time. Their proven design, the vast operating experience<br />

gained locally, their wide availability, reliability and relatively low cost make them an attractive option for base<br />

1<br />

load generation. This is often the case in other parts of the world, such as China , where low-cost coal is<br />

available. The future stations considered consist of 6 units, each of 700 MW installed capacity, with drycooling<br />

(or hybrid) systems. Coal stations can operate with or without flue gas desulphurisation (FGD) to<br />

reduce emissions but only the option with FGD was considered for the plan because of the decision to adhere<br />

to World Bank emission standards. Detailed information on the cost and performance of the PF plants is<br />

shown in Appendix 3.4<br />

5.4.2 New Gas-Fired <strong>Plan</strong>t<br />

Potentially Namibia, Mozambique or Angola could supply Gas. New gas-fired plants considered are open<br />

cycle gas turbines (OCGT) and combined cycle gas turbines (CCGT). Open cycle gas turbines, by virtue of<br />

their low efficiencies and resultant high cost of fuel when operating at low load factors are considered for<br />

peaking options only. Combined cycle gas turbines with much improved efficiency levels are regarded as nonpeaking<br />

technologies due to the likely constraints on gas contracts (take or pay) although they could<br />

technically follow load.<br />

The OCGT stations considered have two 120 MW units. The CCGT stations considered have 5 x 400 MW<br />

units.<br />

If OCGT turbines were built, and in the future a gas network was developed, it is likely that OCGT plants would<br />

be converted to CCGT plants, which would increase the capacity and efficiency of the stations. This has not<br />

been taken into account in the plan.<br />

1 Future Implications of China’s Energy-Technology Choices, July 2001


Reference Case<br />

Fuels considered for OCGT plants are kerosene, LPG, local syngas and LNG. Fuels considered for CCGT are<br />

pipeline gas and LNG. Fuel prices for the gas options are given for all the fuels considered for each technology.<br />

Detailed information on the cost and performance of the OCGT and CCGT plants is shown in Appendix 3.2 and<br />

3.3 respectively.<br />

5.4.3 New Pumped Storage Schemes<br />

Two pumped-storage schemes have been considered in the plan. Braamhoek (which has already received a<br />

record of decision (ROD)) and a generic scheme which would follow Braamhoek. Braamhoek consists of four<br />

333 MW units, while the generic option consists of three 333 MW units. It must be noted that the costing of<br />

pumped storage schemes is site specific. Additional details on the pumped storage plants are provided in<br />

Appendix 3.8.<br />

5.4.4 Greenfield Fluidised Bed Combustion<br />

The fluidised bed combustion (FBC) stations considered have an installed capacity of 500 MW. They are<br />

comprised of two 250 MW boilers and a 500 MW turbine, and have a 35 year lifetime. The price of duff coal will<br />

have to be negotiated between the station and the mines. Additional information on the FBC is provided in<br />

Appendix 3.5.<br />

27


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

28<br />

Table 8: Summary of cost and performance data of new supply-side options


Reference Case<br />

5.4.5 Conventional Nuclear (Advanced Light Water Reactor (ALWR))<br />

The new nuclear plant considered is an advanced light water reactor. It consists of two 900 MW units and will<br />

be built at the Koeberg (existing nuclear) site near Cape Town.<br />

The ALWRs are based on existing light water reactors but are designed for simplicity and ease of construction<br />

and maintenance. They have a considerable degree of inherent safety (safety built in to the design rather than<br />

reliant on active safety mechanisms). Examples of such reactors are the Westinghouse AP1000 and the<br />

General Electric ABWR. There are currently no ALWR plants in operation. Additional information on the ALWR<br />

is provided in Appendix 3.6.<br />

5.4.6 Research projects/programs<br />

In addition to the “mainstream” supply-side options listed above, the following are amongst the technologies<br />

that are being researched and are considered in the screening curve analysis:<br />

5.4.6.1 Wind energy<br />

There are several areas in South Africa, particularly in the coastal regions, which have been identified as<br />

having good potential for wind power. The proposed wind farm consists of twenty (1 MW) wind turbines.<br />

There is little detailed data available for specific sites in South Africa. Additional details on wind turbines are<br />

provided in Appendix 3.9.<br />

5.4.6.2 Solar thermal<br />

The Solar Thermal power station would be built near Upington in the Northern Cape. It would have three 110<br />

MW units and the capacity for storage. It is therefore regarded as a dispatchable station in the plan. Additional<br />

details on solar thermal power stations are provided in Appendix 3.10.<br />

29<br />

5.4.6.3 <strong>PBMR</strong><br />

If the necessary approvals are given and a commercial decision is taken to build one, the first full-sized<br />

demonstration unit should be on line by 2008. If successful, further units will be built with the aim of producing<br />

a power station consisting of eight units, each unit with an installed capacity of 170 MW. Additional details on<br />

the <strong>PBMR</strong> plant are provided in Appendix 3.7<br />

5.4.7 Imported Hydro<br />

There is a large potential for South Africa to import hydro-electricity from the rest of Africa. A promising site is at<br />

Mepanda Uncua in Mozambique about 60 km downstream of the existing Cahora Bassa Power Station on the<br />

Zambezi River. In the first stage of this project the installed capacity at the HV terminals would be 1300 MW.<br />

The firm power capacity at 95% availability is 827 MWe. Additional details on the imported hydro option are<br />

provided in Appendix 3.11.<br />

5.5 Screening Curves<br />

To evaluate the cost of generation from new options, a screening curve analysis was undertaken. A screening<br />

curve evaluates the cost of generating electricity at different average levels of production or load factors over<br />

the life of the plant. This gives an indication of the economics of running the plant at these load factors.<br />

The following screening curves have been drawn from the levelised capital, O&M and fuel costs for the various<br />

technologies at different load factors. The analysis has been split into two sections: non-peaking stations<br />

(plants expected to run at high load factors) and peaking stations (plants expected to run at low load factors).<br />

Non-peaking plants operate as base load when their operating (including fuel) costs are lower than peaking


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

stations. There are some exceptions where stations with high operating costs are included as must run plants<br />

by virtue of fixed price contracts or technical constraints. CCGT options are examples whereby the gas<br />

contracts are placed on the basis of firm commitments to take minimum quantities by virtue of purchasing<br />

power agreements. These plants can be considered as inflexible options to system dispatch and construed as<br />

must run options.<br />

Peaking stations run at low load factors by virtue of their high operating costs generally have lower capital and<br />

fixed operating expenses than non-peaking stations. The ranges reported in the screening curves reflect the<br />

deviation in the data collected from international literature.<br />

Figure 7 illustrates the life cycle costs to build and operate the base load plants analysed in this report.<br />

1500.00<br />

1300.00<br />

1100.00<br />

R/MWh<br />

900.00<br />

700.00<br />

CF with FGD<br />

Conventional Nuclear<br />

<strong>PBMR</strong><br />

Imported Hydro<br />

Solar Thermal<br />

500.00<br />

CCGT LNG<br />

CCGT Pipe<br />

300.00<br />

30<br />

Greenfield FBC<br />

100.00<br />

30 40 50 60 70 80 90<br />

Load Factor (%)<br />

1<br />

Figure 7: Life cycle levelised costs to build and operate base load plants<br />

Figure 8 illustrates the life cycle costs to build and operate the peaking plants analysed in this report.<br />

4000<br />

3500<br />

3000<br />

2500<br />

Gas Turbine (LNG)<br />

Gas Turbine (Local Syngas)<br />

R/MWh<br />

2000<br />

1500<br />

1000<br />

Wind (Non-dispatchable)<br />

Pumped Storage (Generic)<br />

500<br />

Pumped Storage (Braamhoek)<br />

0<br />

0 5 10 15 20 25 30<br />

Load Factor (%)<br />

Figure 8: Life cycle levelised costs to build and operate peaking plants


Reference Case<br />

The open cycle gas turbine levelised cost curves cross the Braamhoek Pumped Storage scheme cost curve<br />

near 6% load factor. They cross the Generic Pumped Storage Scheme near 10% load factor. (Note: Wind<br />

turbines are considered non-dispatchable options operating at low load factor due to paucity of wind resources<br />

in South Africa).<br />

Although some of the technologies overlap in the screening curves shown above, there is a significant<br />

statistical difference between the capital costs of the various technologies at a 95 % confidence interval (see<br />

Appendix 3). The screening curves show that, once capital costs are combined with O&M and fuel costs, the<br />

differences between the total levelised costs of certain technologies are not statistically significant (they<br />

overlap) at certain load factors.<br />

5.6 Other: Environmental, Externalities, Transmission Expansion<br />

Certain sites and technologies will reduce the need to strengthen the electricity grid as they will be built close to<br />

load centres that are currently far from existing generation. This is taken into account in the levelised cost<br />

curves and is described further in the detailed descriptions of the technologies.<br />

All the new coal fired generating options considered meet World Bank emissions standards. Conventional coal<br />

stations will be equipped with flue gas desulphurisation. Due to the limited water resources all new coal<br />

stations are dry cooled.<br />

6.INTEGRATION AND SENSITIVITY ANALYSIS<br />

<strong>Resource</strong>s <strong>Plan</strong>ning has to deal with multiple conflicting objectives, a broad range of options and pervasive<br />

uncertainty. In this context it has to do with dominance and finding plans representing reasonable trade off<br />

amongst various conflicting objectives. If, for example, the objective were to minimise cost then those plans<br />

with higher cost would be considered inferior to those with lower cost. Lower cost plans would therefore<br />

dominate the higher cost plans.<br />

31<br />

The focus of the traditional resources planning approach is to provide a robust (and flexible) plan determined<br />

on the basis of an analysis of risk from either under or over investment within a range of forecast demand for<br />

electricity over a specified planning horizon. (A plan that is 100% robust is one which lies in the decision set for<br />

all futures and would lead to no regret). Flexibility is of equal importance to robustness, if not more important in<br />

the uncertain planning environment. Flexibility can be defined as the ability to modify a resource plan without<br />

significantly degrading system reliability and economics, in response to actual data that have deviated from<br />

the forecast data.<br />

The objective is therefore to provide long-term strategic projections of supply-side and demand-side options<br />

added or deducted from the system over a specified planning horizon taking into account investment risk and<br />

option lead time under a range of different planning scenarios.<br />

The risks associated with this planning process have been outlined previously but predominantly focus on<br />

those uncertainties, which will influence decisions on:<br />

& The timing for new supply-side and demand-side initiatives<br />

& The plant mix


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Due to time constraints, this round of the NIRP focuses on the development of a reference plan only. Elements<br />

of uncertainty and risk are taken into account by imposing constraints on plant operating reserve. In terms of<br />

this process two plans have been developed for this round of the NIRP, namely:<br />

& Reference <strong>Plan</strong> - constrained to 10% reserve margin<br />

& Alternative <strong>Plan</strong> 1 - constrained to 15% reserve margin<br />

& Alternative <strong>Plan</strong> 2 - sensitivity study conducted on the reference plan in order to determine the impact of<br />

excluding Interruptible supply agreements from the plan<br />

& Alternative <strong>Plan</strong> 3 (optimum reserve margin) - non-constrained plan providing as an output the optimum RM<br />

based on trade-off between the cost of reliability of supply and the cost of un-served energy to the<br />

consumer.<br />

The details of these plans are given in Appendix 2 to this report.<br />

6.1 Reference <strong>Plan</strong><br />

The reference plan has a minimum constraint of 10% on the reserve margin as proxy to take account of the risk<br />

elements detailed above. In addition to the constraint on the reserve margin, two further constraints are<br />

imposed.<br />

The first is in terms of the extent of un-served energy that would be allowed. In this case the un-served energy<br />

is constrained to a maximum of 0.011% of total energy demand in any specific year. This is reflective of<br />

historical values utilised in Eskom in previous years in order to ensure a loss of load expectation (LOLE) of 22<br />

hours is not exceeded in any given year.<br />

32<br />

The second is in terms of the number and capacities of Open Cycle Gas turbines accommodated in the plan<br />

because of perceived limitations in the gas supply and the possibility of these options becoming stranded<br />

assets in the event more interruptible supply options are implemented in the future. It was decided in this<br />

instance to consider a maximum number of 10 stations limited to 2x120 MW each could be built in the twentyyear<br />

planning horizon.<br />

The capacity outlook for this plan is illustrated in Figure 9 below and the detailed results are given in Appendix<br />

2 to this report.<br />

Mothballed Coal-Fired FBC GT Pumped Storage Demand-side Options<br />

YR Cam (PF) Gr'tvlei<br />

(PF)<br />

Kom<br />

(PF)<br />

PF (1) PF (2) Greenfield<br />

FBC<br />

OCGT PS (A) PS (B) PS (C) PS (D) CEE IMEE IMLM REE RLM Syst Res<br />

Committed Committed CommittedCommittedCommittedCommittedCommitted<br />

2003 Decide 14 16 41 32 49 24%<br />

2004 Decide Decide 14 16 41 32 49 21%<br />

2005 380 Decide Decide 14 16 41 32 49 18%<br />

2006 380 Decide 14 16 41 32 49 15%<br />

2007 380 Decide Decide 14 16 41 32 49 14%<br />

2008 380 Decide 240 14 16 41 32 49 12%<br />

2009 377 480 14 16 41 32 49 12%<br />

2010 377 303 480 14 16 41 32 49 12%<br />

2011 377 303 480 14 16 41 32 49 10%<br />

2012 303 466 480 333 11%<br />

2013 240 999 11%<br />

2014 466 666 11%<br />

2015 333 333 10%<br />

2016 466 666 11%<br />

2017 932 333 11%<br />

2018 466 333 11%<br />

2019 642 10%<br />

2020 642 1284 12%<br />

2021 1284 1284 12%<br />

2022 1284 1284 11%<br />

TOTAL 1520 1130 909 3852 3852 2796 2400 1332 999 999 666 124 145 368 292 441<br />

Figure 9: Reference plan (10% Reserve Margin)


Reference Case<br />

These results indicate a commitment to ensuring the immediate return to service of Camden power station in<br />

the suite of Eskom Simunye mothballed plants. In addition an immediate decision is required to build at least<br />

720 MW of OCGT plant for commissioning and commercial service by 2009. Furthermore, activities<br />

(monitoring and evaluation) need to be implemented immediately to ensure Braamhoek pumped storage<br />

remains on track for commercial service in 2012, and also that the DSM programmes achieve their targets over<br />

the ensuing years.<br />

6.2 Alternative <strong>Plan</strong> 1 to Reference <strong>Plan</strong><br />

There is a concern that carrying a 10% reserve margin on the moderate national forecast is too conservative in<br />

the light that most international utilities are reluctant to carry a RM below 15%. An additional plan has been<br />

developed which is constrained to a reserve margin of 15%. This plan is detailed in Figure 10 below.<br />

Mothballed Coal-Fired FBC GAS Pumped Storage Demand-side Options<br />

YR<br />

Cam (PF) Gr'tvle<br />

i (PF)<br />

Kom<br />

(PF)<br />

PF (1) PF (2) Greenfield<br />

FBC<br />

CCGT<br />

(1)<br />

CCGT (2) OCGT PS (A) PS (B) PS (C) PS (D) CEE IMEE IMLM REE RLM Syst<br />

Res<br />

Committed Decide Committed Committed Committed Committed CommittedCommitted<br />

2003 Decide Decide Decide Decide 14 16 41 32 49 24%<br />

2004 Decide Decide Decide 14 16 41 32 49 21%<br />

2005 380 14 16 41 32 49 18%<br />

2006 380 Decide 14 16 41 32 49 15%<br />

2007 380 188 Decide 14 16 41 32 49 14%<br />

2008 380 377 202 Decide 480 14 16 41 32 49 15%<br />

2009 377 303 480 14 16 41 32 49 15%<br />

2010 202 466 387 240 14 16 41 32 49 15%<br />

2011 466 774 14 16 41 32 49 14%<br />

2012 188 1161 333 15%<br />

2013 202 999 15%<br />

2014 932 333 15%<br />

2015 666 14%<br />

2016 642 333 15%<br />

2017 466 666 333 15%<br />

2018 642 466 15%<br />

2019 333 13%<br />

2020 1284 333 15%<br />

2021 1284 1284 15%<br />

2022 1284 1284 387 14%<br />

TOTAL 1520 1130 909 3852 3852 2796 1935 774 1200 1332 999 999 999 124 145 368 292 441<br />

33<br />

Figure 10: Alternative <strong>Plan</strong> 1 to reference plan (15% Reserve Margin)<br />

Alternative 1 requires additional capacity of 1842 MW over the planning horizon, at the additional cost of 15<br />

552 million Rand, in order to maintain the higher RM of 15%. The plan also requires acceleration of the return to<br />

service of the mothballed plants and base load PF plant.<br />

6.3 Alternative <strong>Plan</strong> 2 (Sensitivity Study)<br />

A prime concern of ARC members is the uncertainty surrounding the sustainability of interruptible supply<br />

options. In order to determine the impact of interruptible supply options, a further plan (Alternative <strong>Plan</strong> 2) was<br />

developed based on the primary assumptions and constraints used to develop the reference plan but<br />

excluding all interruptible supply options from the plan. This plan is detailed in Figure 11 below.<br />

This plan requires significant acceleration of the return to service programme of the mothballed plants in the<br />

near term. In this, the plan is at risk, because the return to service programme of the Simunye plant, even with<br />

the best endeavours, might be unable to be accelerated sufficiently to meet the demand in the near term<br />

(2006).<br />

There is a PV increase in costs of this plan when compared to the reference plan of 2 997 Million Rand. The<br />

higher cost of this plan is largely due to the fact that there is a penalty paid in interrupting customers in the early<br />

years at a high cost of un-served energy of 20 660 R/MWh.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Mothballed Coal-Fired FBC Gas Pumped Storage Demand-side Options<br />

YR Cam (PF) Gr'tvlei<br />

(PF)<br />

Kom (PF) PF (1) PF (2) Greenfield<br />

FBC<br />

OCGT PS (A) PS (B) PS (C) PS (D) CEE IMEE IMLM REE RLM Syst<br />

Res<br />

Committed Committed Committed Committed Committed Committed Committed<br />

2003 Decide Decide Decide Decide 14 16 41 32 49 19%<br />

2004 Decide Decide 14 16 41 32 49 16%<br />

2005 380 14 16 41 32 49 13%<br />

2006 380 Decide Decide 14 16 41 32 49 10%<br />

2007 380 377 101 14 16 41 32 49 10%<br />

2008 380 101 Decide 480 14 16 41 32 49 11%<br />

2009 377 202 480 14 16 41 32 49 11%<br />

2010 377 303 480 14 16 41 32 49 12%<br />

2011 202 466 480 14 16 41 32 49 11%<br />

2012 466 480 333 11%<br />

2013 999 11%<br />

2014 999 333 11%<br />

2015 333 10%<br />

2016 466 333 333 10%<br />

2017 932 333 11%<br />

2018 642 333 11%<br />

2019 466 10%<br />

2020 642 1284 11%<br />

2021 1284 1284 11%<br />

2022 1284 1284 11%<br />

TOTAL 1520 1130 909 3852 3852 2796 2400 1332 999 999 999 124 145 368 292 441<br />

Figure 11: Alternative <strong>Plan</strong> 2 - sensitivity to reference plan (excludes interruptible supply options)<br />

6.4 Alternative <strong>Plan</strong> 3 (Optimal reserve margin)<br />

The issue of determining an optimal reserve margin for electricity generation in South Africa has not been<br />

addressed formally in any forum in the country to date. In optimal integrated resources planning studies, the<br />

calculation of the reserve margin is an outcome, based on the primary assumptions underpinning the<br />

development of the plan.<br />

34<br />

It is therefore expedient to determine a reserve margin based on the outcome of the optimisation process, but<br />

taking into account specified risk(s) associated with key uncertainties in the primary planning assumptions.<br />

Such a plan will result in a different mix and timing of new plant options compared to one developed to meet a<br />

deterministic reliability index.<br />

The development of such a plan is intended as the outcome of the next round of studies aimed at producing a<br />

recommended set of strategies (plan) for NIRP2 based on an analysis of risk factors associated with the<br />

primary assumptions.<br />

As a starting point to this exercise, an optimal plan has been developed, based on the primary assumptions<br />

listed above without imposing any constraints and in particular on the reserve margin, un-served energy and<br />

number of peaking (OCGT) plants.<br />

This plan is detailed in the Appendix 2 to this report. It is intended that this plan will serve as the basis for the<br />

next round of studies where several different plans will be developed on the basis of meeting a number of risk<br />

scenarios associated with the uncertainties surrounding several of the key assumptions. In each of the plans,<br />

the reserve margin will be an outcome as a function of the risk associated with specified uncertainties.<br />

It is important to state that given certainty in the current primary assumptions, the reserve margin required<br />

would be of the order 4% in the long-term. This plan would however not be sufficiently flexible to meet any of<br />

the short or long-term risks detailed above.


Reference Case<br />

7.SYSTEM ANNUAL AVERAGE LONG RUN MARGINAL COST<br />

In this report, the terms Long Run Marginal Cost (LRMC) and Long Run Incremental Cost (LRIC) are used<br />

interchangeably. Theoretically the LRMC refers to the incremental cost of providing one additional unit of<br />

energy to supply the increase in demand; whereas the LRIC refers to the incremental cost of providing an<br />

additional increment of energy.<br />

The LRMC curve is calculated by determining the difference in costs between two generation expansion plans<br />

developed over the twenty-year planning horizon:<br />

(1) Base case: to meet the forecast demand in electricity and,<br />

(2) Marginal case: the forecast demand increased by an increment (500 MW in this case)<br />

The annual difference in optimal cost for building and operating plant to meet these two plans is divided by the<br />

difference in energy associated with each of these annual forecast demands. (I.e. the base demand and the<br />

demand increased by the increment of 500 MW at the system annual average load factor).<br />

The LRMC has been developed using this methodology, for the reference plan and each of the alternative<br />

plans to the reference plan. The detailed results are given in Appendix 2 attached to this report and illustrated<br />

graphically in Figure 12.<br />

280.0<br />

260.0<br />

System Marginal Cost of NIRP Ref <strong>Plan</strong> at 2003 prices (10% NDR)<br />

240.0<br />

220.0<br />

35<br />

LRMC in R/MWh<br />

200.0<br />

180.0<br />

160.0<br />

140.0<br />

120.0<br />

100.0<br />

80.0<br />

Alt <strong>Plan</strong> 2 (Ref excluding interruptible loads , (R/MWh)<br />

Alt <strong>Plan</strong> 1 (15% RM) (R/MWh)<br />

Ref <strong>Plan</strong> (R/MWh)<br />

60.0<br />

40.0<br />

20.0<br />

0.0<br />

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

Years<br />

Figure 12: Annual average long run marginal costs of plans<br />

Of particular significance in these results are the high values of the LRMC in the early years associated with the<br />

Alternative 2 excluding interruptible supply options. This is because the Simunye mothballed plant cannot be<br />

returned to service in time to avoid interrupting customers at a high cost to the economy.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

8.CONCLUSIONS<br />

The main conclusions drawn from the NIRP2 reference case study could be summarised as follows:<br />

36<br />

1) Options for diversification are insufficient to meet all of the forecast demand for electricity over the next 20-<br />

year planning horizon. Coal-fired options are still required for expansion during this period. For<br />

environmental benefit it is imperative to continue with efforts to reduce the costs of implementing clean<br />

coal technologies and improve the efficiency of coal-fired plants;<br />

2) Base load plants are required for commercial operation from 2010. Base load options competing, include;<br />

Pulverised Fuel Coal-fired (PF); Fluidised Bed Combustion (FBC); Combined Cycle Gas Turbine (CCGT).<br />

Given the cost and performance data used in the plan these options are broadly comparable, at 10% net<br />

discount rate, if regional siting and transmission benefits are included.<br />

3) At the current assumed cost of capital (10% net discount rate) and after returning the Eskom mothballed<br />

plant to service, fluidised bed combustion technologies are South Africa's most economic option, followed<br />

by investment in coal-fired plant. This in turn is followed by importing gas / LNG for CCGT plant in the<br />

Cape. The studies also show that after taking the avoided cost of transmission into account (including<br />

losses) that is not sufficient to make the CCGT plant competitive with coal;<br />

4) It will be difficult to justify diversification on an economic basis, unless penalties for not doing so are<br />

included in future analyses. As the cost for diversification is becoming increasingly more expensive these<br />

penalties (or opportunities for emissions trading) will need to be substantial to offset the economic benefits<br />

of remaining with coal;<br />

5) The NIRP plans are based on attainment and sustainability of the DSM targets , power plants availability,<br />

imports and interruptible loads;<br />

6) The NIRP plans indicate that 920 MW OCGT peak load plants must begin commissioning from 2008;<br />

7) Maintaining a higher reserve margin of 15% over the planning period will require acceleration of the RTS of<br />

the mothballed plants and coal-fired options together with commissioning of additional base load capacity<br />

(CCGT);<br />

8) Diversified options are new technologies to South Africa. If these options for whatever reason are not able<br />

to be implemented it will mean a return to a dependency on new pulverised coal-fired plants earlier than<br />

shown in these plans;<br />

9) There are supply options that have not been considered such as co-generation in industry, converting<br />

OCGT to CCGT, adding units onto existing power stations and new imports resulting from the<br />

development of Electricity Supply in the Southern African region;<br />

10) Should interruptible supply and / or OCGT capacity not be implemented this will significantly advance<br />

new base-load capacity;


Risk & Sensitivity Analysis<br />

<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Stage 2<br />

Risk & Sensitivity Analysis<br />

37<br />

COMPILED BY<br />

The <strong>National</strong> Electricity Regulator<br />

ISEP Eskom (<strong>Resource</strong>s and Strategy)<br />

Energy Research Institute<br />

University Of Cape Town


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

NIRP 2 STAGE 2:<br />

RISK AND UNCERTAINTY ANALYSIS<br />

TABLE OF CONTENTS<br />

1 INTRODUCTION 40<br />

2 SCOPE OF STUDY 40<br />

2.1 APPROPRIATE RESERVE MARGIN 40<br />

2.2 IDENTIFIED RISKS AND UNCERTAINTIES 41<br />

2.3 IMPACT OF THE SELECTED RISK PORTFOLIOS 42<br />

38<br />

3 MODELED UNCERTAINTIES 43<br />

3.1 FORECAST 43<br />

3.1.1 Background 43<br />

3.1.2 Compilation of the energy component of the higher forecast 43<br />

3.1.3 Compilation of the demand component of the higher forecast 44<br />

3.1.4 Forecast Data 46<br />

3.2 AVAILABILITY OF PLANT 47<br />

3.3 SUSTAINABILITY OF EXISTING INTERRUPTIBLE LOADS 48<br />

3.4 SUSTAINABILITY OF EXISTING CAPACITY 48<br />

4 SCENARIO DEVELOPMENT 49<br />

5 RANKING OF PLANS/CANDIDATE PLANS 51<br />

5.1 METHODOLOGY 51<br />

5.2 TOTAL PROBABILITY-WEIGHTED COST 52<br />

5.3 RELIABILITY ASSESSMENT 53<br />

5.4 EMISSIONS AND DIVERSIFICATION ASSESSMENT 54<br />

6 PREFERRED RESOURCE PLAN 56<br />

6.1 PREFERRED PLAN 14 56<br />

7 SENSITIVITY ANALYSIS 57<br />

7.1 COMPARISON OF DATA CHANGES TO NIRP2 REFERENCE PLAN 57<br />

7.2 THE IMPACT OF NET DISCOUNT RATE ON OPTIMUM CHOICE OF TECHNOLOGY 59<br />

7.3 RENEWABLE ENERGY TECHNOLOGIES 62<br />

8 CONCLUSIONS 64<br />

9 APPENDICES 64


Risk & Sensitivity Analysis<br />

LIST OF FIGURES<br />

Figure 1. Impact of Modelled Uncertainties 43<br />

Figure 2. Energy Forecasts 44<br />

Figure 3. Maximum Demand Forecasts 45<br />

Figure 4. The proportion of consumption increases over the reference case. 47<br />

Figure 5. Variability of total cost. 53<br />

Figure 6. Reserve Margin under own future. 53<br />

Figure 7. Reserve Margin under A1 future. 54<br />

Figure 8. Ranking of <strong>Plan</strong>s 56<br />

Figure 9. Capex Costs for Base Options 58<br />

Figure 10. O&M Costs for NIRP 2 Reference <strong>Plan</strong> and NIRP 2 Risk & Sensitivity <strong>Plan</strong> 58<br />

Figure 11. Fuel Costs for NIRP 2 Reference <strong>Plan</strong> and NIRP 2 Risk & Sensitivity <strong>Plan</strong> 59<br />

Figure 12. Levelised costs of base-load plants versus Net Discount Rate for the<br />

NIRP 2 Reference <strong>Plan</strong> 61<br />

Figure 13. Levelised costs of base-load plants versus Net Discount Rate for the<br />

NIRP 2 Risk & Sensitivity analysis 61<br />

Figure 14. Preferred <strong>Plan</strong> 14 with Renewables 63<br />

Figure 15. Reduction in environment emissions in preferred <strong>Plan</strong> 14 with renewables. 63<br />

LIST OF TABLES<br />

Table 1. Forecasting Data 46<br />

Table 2. Electricity demand in the high growth scenario (GWh) 47<br />

Table 3. Availabilities of new plant. 48<br />

Table 4. Probabilities associated with primary assumptions. 49<br />

Table 5. Scenarios and their probabilities. 50<br />

Table 6. PWC Ranking of the <strong>Plan</strong>s 52<br />

Table 7. Comparison of Candidate <strong>Plan</strong>s 55<br />

Table 8. Preferred <strong>Plan</strong> 14. 57<br />

Table 9. Levelised costs of candidates for selection in the NIRP2 Reference <strong>Plan</strong> 60<br />

Table 10. Levelised costs of candidates for selection for the NIRP2 Risk and Sensitivity<br />

analysis 60<br />

Table 11. Additional Cost of Renewable Technologies 62<br />

39


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

1.Introduction<br />

This Report is an update of the NIRP2 Reference <strong>Plan</strong>. This work was commissioned following comments<br />

received from both the Public and the NER Advisory Review Committee (ARC) after the publication of the<br />

NIRP2 Reference <strong>Plan</strong>.<br />

This Report should be read in conjunction with that of the NIRP2 Reference <strong>Plan</strong> since it uses as basis the<br />

primary planning assumptions (including the data base) of the reference plan unless stated otherwise. Where<br />

data revisions have been made to the reference data, these are explained in the Report. The list of<br />

abbreviations and bibliography of the NIRP2 Reference <strong>Plan</strong> apply to this Report.<br />

The objective of this study is to provide a robust plan for NIRP2 based on an appropriate net reserve margin<br />

above the expected annual maximum demand for electricity assumed in the Reference plan. This reserve<br />

margin is calculated as an outcome based on an analysis of specified probability weighted risk portfolios.<br />

A complete listing of comments from the Advisory Review Committee (ARC) of the NER plus comments from<br />

individual members of the Public concerning the NIRP2 Reference <strong>Plan</strong> are contained in Appendix A attached<br />

to this Report. The most important aspects leading to the need to carry out a risk and sensitivity analysis are<br />

summarized below:<br />

& The use of deterministic reserve capacity margin as a substitute for risks, without explicitly identifying the<br />

mitigated risks associated with the planning uncertainties (plant availability, load forecast deviations, fuel<br />

availability, interruptible supplies etc), is not ideal planning method;<br />

40<br />

& The appropriate reserve margin should be an outcome of a risk and uncertainty analyses, characteristics of<br />

the existing and future plants and costs. The reserve margin should be an outcome of the modeling process<br />

based on sets of defined assumptions for different scenarios;<br />

& The impact of the discount rate on the optimum choice of technology should be considered in the analyses;<br />

& Considerations regarding resource alternatives under high growth scenarios should be included;<br />

& The costs of some generation sources such as FBC and imported hydro, as well as the cost of the coal are<br />

underestimated;<br />

& The Inclusion of Government renewable energy targets.<br />

2.Scope of study<br />

The major concern expressed by the ARC and members of the Public were expressed in the many comments<br />

regarding an appropriate reserve margin to cater for risk. This report therefore focuses on developing a robust<br />

plan with an appropriate reserve margin accounting for risk. It also takes into account as far as possible<br />

attributes other than least cost such as environmental emissions, flexibility and a diversified portfolio of<br />

options.<br />

2.1 Appropriate Reserve Margin<br />

The reference plan used two levels of deterministic net reserve margin (10% and 15%) to take account of risk.<br />

The use of a deterministic net reserve margin to address risk, without explicitly identifying and quantifying the<br />

risks associated with the primary planning uncertainties (e.g. plant availability, load forecast deviations, fuel<br />

availability, interruptible supplies etc), is not an ideal planning method.


Risk & Sensitivity Analysis<br />

An appropriate net reserve margin should consist of a plant mix which matches the risk impacting the capacity<br />

shortage; E.g. If Cahora Bassa units became unavailable , base-load capacity would be required to meet the<br />

shortfall. If interruptible capacity became unavailable, peaking plant would be required.<br />

Following discussions at the Advisory Review Committee and resulting from the various comments received, it<br />

was decided to adopt the following approach to determine a appropriate net reserve margin for stage2 of<br />

NIRP2.<br />

& Develop scenarios and assign probabilities<br />

& Develop plans for each scenario<br />

& Carry out trade-off analyses (I.e. Test each plan under each scenario and calculate the total probability<br />

weighted cost (cost of supply plus cost of non-supply) of each plan multiplied by the probability of<br />

occurrence of the scenario<br />

& Select the most robust (flexible) plan under agreed attributes<br />

Evaluate the net reserve margin of this plan in respect of the expected forecast<br />

2.2 Identified risks and uncertainties<br />

Following the NIRP2 Reference plan, the following short-term and long-term risks and uncertainties were<br />

identified for inclusion in the risk and uncertainty analysis.<br />

& <strong>Plan</strong>t failure leading to longer than expected plant outage;<br />

& Unavailability of municipal / Eskom / imported generating capacity;<br />

& Degree of market penetration of DSM and maintaining current level of interruptible loads;<br />

& Unexpected decrease / increase, spurious or sustained, of electricity demand;<br />

& Changes to the load shape associated with the forecast electricity demand;<br />

& Unexpected decommissioning / de-rating of existing generating capacity<br />

& Uncertain and prolonged lead times for building new plant;<br />

& Project slippage<br />

& Inclusion of co-generation options;<br />

& Embargoes on nuclear energy;<br />

& Shortage of skills to maintain and grow the system;<br />

& Other energy forms displacing electricity in the energy market;<br />

& Revolutionary technologies coming on the scene and stranding existing assets;<br />

& Internalisation of externalities, such as introduction of a carbon tax and environmental levy;<br />

& <strong>Plan</strong>t life expectations not met;<br />

& Deterioration in credit rating, exchange rates etc. resulting in a higher cost of capital;<br />

& Electricity supply and sales contracts (import and export contracts) being reneged upon;<br />

& Effect of AIDS on the electricity market.<br />

& Drought and Floods<br />

41<br />

Many of these risks and uncertainties are inter-dependent. By aggregating some risk events into independent<br />

risk portfolios it is possible to provide a net reserve margin to cater for a number of risk events under the<br />

umbrella of one independent risk portfolio. This can best be illustrated by the following examples:<br />

Drought: The impact of drought on Hydro imports (Cahora Bassa) can be taken into account by reducing the<br />

capacity of this option. The level of capacity reduction from Cahora Bassa can also be increased to cater for<br />

reduced imports due to increasing capacity withdrawals to neighbouring states (notwithstanding current<br />

agreements) in the future. Although strictly speaking these two events can be construed as separate events<br />

each with their own probability of occurrence, for the purposes of this report the level of capacity reduction is<br />

set to accommodate both with the same probability.<br />

No account is taken of the impact of drought on existing Hydro capacity because the amount of such Hydro in


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

this country is very low. Drought also impacts both cooling water supplies of existing and new coal-fired plants.<br />

This is mitigated to some extent by the fact that all new inland base plants are considered to be dry-cooled (or in<br />

the least dry-cooled with wet assistance at high ambient temperatures). Those located at the coast use once<br />

through sea water cooling.<br />

Flood: This impacts the availability of fuel supplies to the coal-fired plants, mitigated to some extent by those<br />

stations with open cast mines (these are more likely to be impacted) carrying higher stock levels. From the<br />

point of view of imported Hydro, a substantial energy loss could be averted in times of flood, through<br />

implementing a SAPP Zambesi River Authority to ensure for example that where possible water is not let out of<br />

higher altitude dams (Kafua) whilst lower altitude dams (Cahora Bassa) are spilling.<br />

Impact of fuel cost / price: The South African Electricity Supply is heavily dependent on coal as feedstock. In<br />

the event that there was a major price increase in the cost of coal, the economy would be at risk. There are<br />

proponents to providing a diversified approach to building new generating options which may also be more<br />

favorable in reducing environmental and greenhouse gas emissions. This aspect is addressed in that three<br />

new base technologies other than conventional coal-fired plants are considered: Fluidised Bed Combustion<br />

(FBC), Nuclear Pebble Bed Modular Reactors, Gas Combined Cycle (CCGT) options.<br />

Following discussions with various experts in their specific fields, it was decided to address the following four<br />

risk portfolios, considered to be largely independent of each other and as having a major impact on the plant<br />

mix, timing and requirement for carrying reserve, namely:<br />

42<br />

& Level of risk associated with the moderate national forecast being higher and particularly in the near-term to<br />

medium-term;<br />

& Level of risk associated with Eskom and non-Eskom generators being able to sustain high levels of plant<br />

availability once the system becomes stressed and the plants age;<br />

& Level of risk of Non-Eskom and Import capacity becoming unavailable or unreliable (i.e. being de-rated) and<br />

particularly in the near-term;<br />

& Availability of interruptible supply options continuing to serve as reserve capacity. Already these options are<br />

severely energy constrained and their capacity impact has been reduced.<br />

2.3 Impact of the selected risk portfolios<br />

Following discussions with respective experts the following levels of risk were identified for each of the risk<br />

portfolios:<br />

& <strong>National</strong> moderate Load forecast increased by 2570MW in 2007 to 5078MW in 2022 to account for higher<br />

GDP growth and colder weather (Base-load to Peaking)<br />

& <strong>Plan</strong>t availability reduced from 88% to 85% due to poorer FOR (Base-load).<br />

& Contracted Interruptible Supply Excluded:<br />

> Mozal, Alusaf, Ferrochrome and other industries (Peaking)<br />

& Capacity Reductions:<br />

> Cahora Bassa capacity reduced from 1281MW by 250MW in 2004 and 500MW thereafter (Base-load)<br />

> Non-Eskom OCGT capacity (180MW of 270MW) assumed unavailable over the planning horizon<br />

(Peaking)<br />

> Non-Eskom coal-fired capacity (600MW of 1920MW) assumed unavailable over the planning horizon<br />

(Base-load)


Risk & Sensitivity Analysis<br />

The impact of these levels of uncertainty over the planning horizon is illustrated graphically in Figure 1 below.<br />

Impact of Modelled Uncertainties<br />

10000<br />

9000<br />

8000<br />

7000<br />

Capacity (MW)<br />

6000<br />

5000<br />

4000<br />

3000<br />

Capacity impact of excluding Import and Munic capacity (MW)<br />

Capacity Impact of excluding DSM Interruptible load (MW)<br />

Capacity impact of increased load forecast (MW)<br />

Capacity impact of reduced plant availability (89% to 85%) (MW)<br />

2000<br />

1000<br />

0<br />

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

Years<br />

Figure 1: Impact of Modelled Uncertainties<br />

3.Modelled Uncertainties<br />

These risk portfolios were generated on the basis of the comments made on the primary assumptions by the<br />

ARC and in consultations with various experts. Following is a description of the levels or risk associated with<br />

the primary assumptions as detailed in the NIRP2 Reference <strong>Plan</strong>.<br />

43<br />

3.1 Forecast<br />

3.1.1 Background<br />

The NIRP2 reference plan is based on a moderate demand for electricity developed by Eskom. This forecast<br />

used moderate GDP growth and moderate weather conditions. It was recommended by the ARC to also<br />

develop a forecast of accelerated demand growth for the risk and uncertainty analysis, reflecting colder<br />

weather conditions and higher GDP growth (especially in the near-term). It was not considered necessary by<br />

the ARC to use a lower forecast than the moderate, the moderate being considered to be already reflective of a<br />

lower than expected scenario. It was agreed that the Energy Research Centre (ERC) would develop the high<br />

growth forecast independent of Eskom. Eskom resources would be used to transform the energy forecast into<br />

hourly annual demand values according to Eskom sector profiles.<br />

3.1.2 Compilation of the energy component of the higher forecast<br />

The higher energy forecast in demand for electricity was developed by ERC based on energy forecasting<br />

techniques incorporated in the LEAP model (SEIB 2002; Howells et al 2002; and Hughes et al, 2003), and the<br />

Integrated <strong>Resource</strong> <strong>Plan</strong>ning manual of the United Nations Environment Program (UNEP 1998). It considers<br />

a relatively detailed breakdown of electricity consuming sectors. For example, the mining sector was divided<br />

into nine different sub-sectors, as was the industrial sector. Added to this was the commercial, transport,<br />

agricultural and residential sectors. A relationship was developed between the outputs of these sectors and the<br />

future Gross Domestic Product (GDP) (with the exception of the residential sector) as a basis for future<br />

electricity demand. The relationship between GDP and sector output is time dependant with the proportional<br />

contribution of each sector changing over time. The sector outputs considered was either value added, or<br />

physical output.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

In line with the assumptions approved by ARC, the ERC developed a high forecast which used higher than<br />

expected growth in the near- to medium-term in specific sectors. The growth associated with this forecast is<br />

higher than that of the moderate forecast of the NIRP2 Reference plan by an estimated half a percentage point<br />

in the short to medium term.<br />

When the results of the ERC energy forecast are compared to that of the Eskom model they will differ in certain<br />

respects. A forecast with a higher growth rate will automatically imply a different sectoral energy mix.<br />

Furthermore, the energy model used by the ERC makes use of sectoral data of a more aggregated nature than<br />

the Eskom sectoral model.<br />

A comparison of the energy forecasts for the previous NIRP1, NIRP2 reference case and this analysis is<br />

shown in the Figure 2 below.<br />

Energy sent out<br />

400000<br />

44<br />

Annual energy sent out [GWh]<br />

350000<br />

300000<br />

250000<br />

200000<br />

NIRP1 Moderate growth and moderate weather<br />

NIRP2 Moderate growth and moderate weather<br />

NIRP2 High growth and cold weather<br />

150000<br />

2001<br />

2003<br />

2005<br />

2007<br />

2009<br />

2011<br />

2013<br />

2015<br />

2017<br />

2019<br />

2021<br />

2023<br />

2025<br />

Year<br />

Figure 2:. Energy Forecasts<br />

3.1.3 Compilation of the demand component of the higher forecast<br />

The energy forecast is transformed into an hourly demand forecast (instantaneous demands averaged over<br />

each hour) with the HELM (Hourly Electric Load Model) computer model. The model uses:<br />

& Detailed sectoral load profiles developed by Eskom<br />

& Energy sales forecast and losses as inputs<br />

& Temperature as an input where the impact is determined through pre-determined formulae (E.g. for<br />

extremely cold weather).<br />

& Output is hourly maximum demands in each year over the whole planning horizon<br />

The following assumptions were used in developing this demand forecast:<br />

& The ERC energy sales forecast as described above;<br />

& Updated sectoral demand profiles, which were obtained from recent load research carried out by Eskom<br />

consultants in 2003;<br />

& The system load factor was constrained to deteriorate within a narrowband (from 72% in 2004 to 70% in<br />

2022).


Risk & Sensitivity Analysis<br />

& Based on 1996 weather conditions which is recorded as the coldest weather <strong>National</strong>ly over the last 12 years<br />

& No new demand side management initiatives are included in the forecast from 2003 (I.e. from the beginning<br />

of the planning horizon)<br />

It is pertinent to note that the system losses as calculated by the ERC and used in this analysis are marginally<br />

different to those calculated by Eskom. The annual maximum demands for the various NIRP studies are<br />

compared in Figure 3below.<br />

65000<br />

Maximum demand<br />

60000<br />

Maximum demand [MW]<br />

55000<br />

50000<br />

45000<br />

40000<br />

35000<br />

30000<br />

25000<br />

NIRP1 Moderate growth with moderate weather<br />

NIRP2 Moderate growth with moderate weather<br />

NIRP2 High growth with cold weather<br />

2001<br />

2003<br />

2005<br />

2007<br />

2009<br />

2011<br />

2013<br />

2015<br />

2017<br />

2019<br />

2021<br />

2023<br />

2025<br />

Year<br />

45<br />

Figure 3:. Maximum Demand Forecasts<br />

3.1.3.1.1 Weather<br />

The 1996 <strong>National</strong> weather pattern was used to estimate weather impact because statistically it was found to<br />

be the coldest over the last twelve years. The impact of this colder weather is to increase the annual peak<br />

demand of the moderate forecast by approximately 3% in 1996 and extrapolated for the other years in the<br />

planning horizon.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

3.1.4 Forecast Data<br />

The relevant data supporting the Figures illustrated above are given in the Table 1 below.<br />

NIRP1 (Moderate) NIRP2 (Moderate) NIRP2 (High)<br />

Moderate Growth and moderate<br />

weather (Forecast energy and losses<br />

determined by Eskom)<br />

Moderate Growth and moderate<br />

weather (Forecast energy and losses<br />

determined by Eskom)<br />

Higher Growth and cold weather<br />

(Forecast energy and losses<br />

determined by ERC)<br />

Year<br />

NIRP1 MW<br />

Moderate Increase<br />

per<br />

Year<br />

(MW)<br />

Sales<br />

GWh<br />

Losses<br />

%<br />

Annual<br />

Energy<br />

(GWh)<br />

NIRP2<br />

Moderate<br />

Demand<br />

(MW)<br />

MW<br />

Increase<br />

per<br />

Year<br />

(MW)<br />

Sales<br />

GWh<br />

Losses<br />

%<br />

Annual<br />

Energy<br />

(GWh)<br />

NIRP2 MW<br />

High Increase<br />

Demand per<br />

(MW) Year<br />

(MW)<br />

Sales<br />

GWh<br />

Losses<br />

%<br />

Annual<br />

Energy<br />

(GWh)<br />

46<br />

1999 177689<br />

2000 181908<br />

2001 32316 185171 9.88 205476<br />

2002 33283 967 188747 10.83 211665<br />

2003 34499 1216 194240 11.63 219794 33645 197189 9.15 217044 34624 197401 9.21 217426<br />

2004 35684 1185 202858 10.81 227439 34914 1269 205159 9.15 225824 36817 1274 209722 9.33 231303<br />

2005 36784 1100 212559 9.19 234066 36146 1232 212415 9.15 233805 38394 1238 218274 9.45 241054<br />

2006 37867 1083 220649 8.24 240457 37632 1486 221593 9.27 244242 39931 1466 227001 9.57 251024<br />

2007 38811 944 225444 8.22 245623 38528 896 226305 9.27 249423 41098 902 232602 9.69 257560<br />

2008 39798 987 230669 8.15 251128 39440 912 231064 9.26 254657 42166 919 237671 9.81 263523<br />

2009 40784 986 235125 8.51 256984 40377 937 236245 9.33 260559 43387 930 243686 9.93 270552<br />

2010 41835 1051 239711 8.84 262952 41389 1012 241799 9.33 266681 44574 1018 249547 10.05 277429<br />

2011 42864 1029 244139 9.26 269068 42342 953 247295 9.34 272762 45777 961 255450 10.17 284370<br />

2012 43894 1030 248886 9.53 275118 43389 1047 253220 9.41 279513 47091 1039 262064 10.29 292123<br />

2013 44893 999 253810 9.64 280896 44343 954 258581 9.41 285448 48275 962 267718 10.42 298859<br />

2014 45922 1029 258683 9.83 286883 45271 928 263829 9.42 291258 49423 936 273173 10.54 305358<br />

2015 46971 1049 263584 10.04 292993 46198 927 268355 9.55 296678 50520 903 278263 10.66 311465<br />

2016 47980 1009 268586 10.22 299148 47034 836 273055 9.56 301910 51597 844 283176 10.78 317391<br />

2017 49068 1088 273812 10.37 305500 47939 905 277825 9.56 307194 52692 913 288139 10.90 323388<br />

2018 50199 1131 278976 10.64 312198 48901 962 282731 9.63 312847 53839 954 293445 11.02 329788<br />

2019 51350 1151 284268 10.88 318978 49841 940 287716 9.63 318375 54976 948 298636 11.14 336075<br />

2020 52507 1157 289652 11.10 325802 50790 949 292725 9.63 323929 56118 958 303850 11.26 342405<br />

2021 53739 1232 295143 11.32 332817 52249 1459 297965 10.64 333445 57101 1072 308905 11.38 348572<br />

2022 54936 1197 300639 11.55 339879 53256 1007 303304 10.64 339407 58334 1013 314602 11.50 355483<br />

2023 56182 1246 306176 11.74 346911<br />

2024 57400 1218 311731 11.96 354066<br />

2025 58673 1273 317332 12.16 361269<br />

Average 1098 1032 1013<br />

Table 1: Forecasting Data<br />

3.1.4.1 Changes in higher forecast from reference case<br />

The difference between the NIRP2 Reference case forecast and this high growth forecast is due mostly to an<br />

increase in industrial demand. This is illustrated in a breakdown of differences in consumption for the year<br />

2013 as shown in Figure 4.


Risk & Sensitivity Analysis<br />

Transport<br />

Residential<br />

Mining<br />

Agriculture<br />

Commerce<br />

Industry<br />

Figure 4: The proportion of consumption increases over the reference case.<br />

A detailed breakdown in GWh of demand consumption for the high growth case is given in Table 2 below.<br />

Table 2: Electricity demand in the high growth scenario (GWh)<br />

Sector/Year 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013<br />

Transport 3432 3569 3656 3752 3782 3807 3847 3886 3930 3987 4029<br />

Mining 31923 33204 34079 34987 35228 35326 35528 35678 35966 36398 36694<br />

Total Industry 91658 97999 101415 105855 108896 111698 115107 118308 121313 124531 127563<br />

Commerce 18360 19537 20450 21449 22058 22633 23317 23968 24660 25457 26161<br />

Agriculture 6310 6728 7055 7408 7621 7819 8052 8267 8493 8755 8985<br />

Residential 32884 34866 36325 37431 38882 40202 41596 42944 44296 45650 46982<br />

Total domestic<br />

ex own<br />

generation 184568 195903 202981 210881 216468 221484 227446 233052 238659 244779 250414<br />

47<br />

3.2 Availability of plant<br />

The plant availabilities of new plants for the NIRP2 Reference <strong>Plan</strong> are based on the World Energy Council<br />

(WEC) best quartile results for 2002. For existing plants the NIRP2 Reference <strong>Plan</strong> uses the current targets in<br />

Eskom adjusted independently for each individual station to give a weighted average for base-load capacity of<br />

88% EAF; (7% PCLF: 3% UCLF with a provision of 2% for OCLF to cater for risk).<br />

The above availability levels were considered too optimistic by the ARC. It was decided to use average results<br />

rather than best quartile taken from the WEC Report 2001 as being reflective of a lower level of plant<br />

availability. (Note: Later editions of WEC Reports do not accurately reflect global plant availability levels<br />

because fewer and fewer utilities are providing input to the WEC database as competition in the Electricity<br />

Supply Industry increases. Figures are now biased towards a few remaining large utility players still<br />

contributing). For existing plants this study uses lower Eskom targets adjusted independently for each<br />

individual station to give a weighted average for base-load capacity of 85% EAF; (7% PCLF: 6% UCLF with a<br />

provision of 2% for OCLF).<br />

A comparison of plant availability levels for this analysis as compared to the NIRP2 Reference <strong>Plan</strong> is given in<br />

Table 3 below for all new plant options.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Table 3: Availabilities of new plant.<br />

48<br />

Option Expected Low Option Expected Low<br />

New Coal with FGD<br />

New Gt Open Cycle (LNG)<br />

PORg 7.20% 7.20% PORg 7.08% 7.08%<br />

FORg 5.17% 7.97% FORg 7.31% 13.90%<br />

Availability 88.00% 85.40% Availability 86.13% 80.00%<br />

New Coal without FGD<br />

New Gt Open Cycle (Kerosene)<br />

PORg 7.20% 7.20% PORg 7.08% 7.08%<br />

FORg 5.17% 7.97% FORg 7.31% 13.90%<br />

Availability 88.00% 85.40% Availability 86.13% 80.00%<br />

New Pumped Storage<br />

Renewables (CSP)<br />

PORg 1.66% 1.66% PORg 3.85%<br />

FORg 1.26% 4.82% FORg 1.98%<br />

Availability 97.10% 93.60% Availability 94.25%<br />

New Fluidised Bed<br />

Renewables (Wind)<br />

PORg 10.20% 7.69% PORg 2.00% 2.00%<br />

FORg 4.57% 8.89% FORg 1.02% 8.16%<br />

Availability 85.70% 84.10% Availability 97.00% 90.00%<br />

CCGT Pipeline Excl Trans<br />

Public <strong>PBMR</strong> (1st MM) Excl Tran<br />

PORg 8.73% 8.73% PORg 4.04% 4.04%<br />

FORg 6.46% 9.61% FORg 4.13% 8.29%<br />

Availability 85.37% 82.50% Availability 92.00% 88.00%<br />

CCGT LNG Exc Trans<br />

Public <strong>PBMR</strong> (1st MM) Inc Tran<br />

PORg 8.73% 8.73% PORg 4.04% 4.04%<br />

FORg 6.46% 9.61% FORg 4.13% 8.29%<br />

Availability 85.37% 82.50% Availability 92.00% 88.00%<br />

CCGT LNG Inc Trans<br />

Public <strong>PBMR</strong> Series No Trans<br />

PORg 8.73% 8.73% PORg 4.04% 4.04%<br />

FORg 6.46% 9.61% FORg 2.04% 6.21%<br />

Availability 85.37% 82.50% Availability 94.00% 90.00%<br />

New Gt Open Cycle (Local Syngas) Nuclear<br />

PORg 7.08% 7.08% PORg 15.00%<br />

FORg 7.31% 13.90% FORg 7.65%<br />

Availability 86.13% 80.00% Availability 78.50%<br />

3.3 Sustainability of existing interruptible loads<br />

The current contracts entered between customers and Eskom concerning interruptible supply are severely<br />

constrained in terms of their usage requirements. Studies carried out in Eskom comparing these options with<br />

equivalent OCGT capacity showed that they should be de-rated to obtain equivalence. In anticipation of future<br />

Demand Market Participation or other Demand Response mechanisms becoming available, it was considered<br />

prudent by the ARC to consider the possibility that current interruptible supply contracts may be re-negotiated<br />

in the future. As such some plans should be developed on the basis of excluding them from the planning base<br />

in the risk analysis.<br />

3.4 Sustainability of existing capacity<br />

As stated previously, some risk events are aggregated into independent risk portfolios. The aggregated<br />

options in each portfolio are assigned the same probability of occurrence for purposes of this Report.<br />

The following capacity reductions are included as aggregated options in this analysis. The levels of capacity<br />

reductions are based on either ARC recommendations or expert opinion:


Risk & Sensitivity Analysis<br />

& Cahora Bassa capacity is reduced by 250MW (from 1281MW) in 2004 and by 500MW thereafter. This is a<br />

base-load capacity reduction;<br />

& Non-Eskom OCGT capacity is reduced by 180MW (from 270MW) and assumed unavailable over the<br />

planning horizon. This is a Peaking capacity reduction;<br />

& Non-Eskom coal-fired capacity is reduced by 600MW (from 1920MW) and assumed unavailable over the<br />

planning horizon. This is a base-load capacity reduction. In addition, this latter option targets Municipal<br />

capacity destined for decommissioning from 2011.<br />

4.Scenario Development<br />

It was agreed by the ARC to carry out the risk and uncertainty analysis to develop an appropriate net reserve<br />

margin using a <strong>Resource</strong>s <strong>Plan</strong>ning approach. The focus of this approach is to provide a best (robust and<br />

flexible) plan developed from an analysis of the risk portfolios and then compare the capacity of the selected<br />

plan with the expected demand to establish an appropriate net reserve margin.<br />

(Note: A plan that is 100% robust is one, which lies in the decision set for all futures and would lead to no regret<br />

whereas flexibility is the ability to modify a resource plan without significantly degrading system reliability and<br />

economics, in response to actual data that have deviated from the forecast data).<br />

There are four risk portfolios defined each consisting two alternatives. This results in sixteen scenarios<br />

incorporating the alternative risk events from each risk portfolio. Optimal plans are then developed for each of<br />

the sixteen scenarios where the basis for the optimisation is the least cost of electricity for the supply life cycle.<br />

This considers the least cost of each plan in terms of the cost of supply and the cost of non-supply (CUE) to the<br />

consumer. For this NIRP2 as explained in the NIRP2 Reference <strong>Plan</strong>, the CUE is assumed to be<br />

R20 666/MWh.<br />

Probabilities were assigned to each of the risk portfolios using a Delphi approach in consultation with the<br />

various experts in the field associated with developing the portfolios.<br />

49<br />

Table 4 below details the probabilities assigned to each of the risk portfolios.<br />

Table 4: Probabilities associated with primary assumptions.<br />

Uncertainties: Probability Probability<br />

Load Forecast Expected (Moderate) (ED) 0.6 High (HD) 0.4<br />

<strong>Plan</strong>t outage Expected (EF) 0.4 High (HF) 0.6<br />

Capacity availability Expected (EC) 0.3 Low (LC) 0.7<br />

DSM Interruptible Load Expected (EI) 0.4 Low (LI) 0.6<br />

Table 5 below details the sixteen scenarios incorporating the alternative risk events from each risk portfolio<br />

with the resultant probabilities assigned to each scenario.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Table 5: Scenarios and their probabilities.<br />

Futures <strong>Plan</strong> A-1 / Scenario 1 <strong>Plan</strong> A-2 / Scenario 2<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage Expected (EF) High (HF)<br />

Capacity availability Expected (EC) Low (LC)<br />

DSM Interruptible Supply Expected (EI) Low (LI)<br />

Probability 0.0288 0.1008<br />

Futures <strong>Plan</strong> A-3 / Scenario 3 <strong>Plan</strong> A-4 / Scenario 4<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage High (HF) Expected (EF)<br />

Capacity availability Low (LC) Expected (EC)<br />

DSM Interruptible Supply Low (LI) Expected (EI)<br />

Probability 0.1512 0.0192<br />

Futures <strong>Plan</strong> A-5 / Scenario 5 <strong>Plan</strong> A-6 / Scenario 6<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage High (HF) High (HF)<br />

Capacity availability Expected (EC) Low (LC)<br />

DSM Interruptible Supply Low (LI) Expected (EI)<br />

Probability 0.0648 0.0672<br />

50<br />

Futures <strong>Plan</strong> A-7 / Scenario 7 <strong>Plan</strong> A-8 / Scenario 8<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage Expected (EF) High (HF)<br />

Capacity availability Low (LC) Expected (EC)<br />

DSM Interruptible Supply Low (LI) Expected (EI)<br />

Probability 0.1008 0.0288<br />

Futures <strong>Plan</strong> A-9 / Scenario 9 <strong>Plan</strong> A-10 / Scenario 10<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage Expected (EF) Expected (EF)<br />

Capacity availability Expected (EC) Expected (EC)<br />

DSM Interruptible Supply Low (LI) Low (LI)<br />

Probability 0.0432 0.0288<br />

Futures <strong>Plan</strong> A-11 / Scenario 11 <strong>Plan</strong> A-12 / Scenario 12<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage High (HF) Expected (EF)<br />

Capacity availability Expected (EC) Low (LC)<br />

DSM Interruptible Supply Expected (EI) Expected (EI)<br />

Probability 0.0432 0.0448<br />

Futures <strong>Plan</strong> A-13 / Scenario 13 <strong>Plan</strong> A-14/ Scenario 14<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage High (HF) Expected (EF)<br />

Capacity availability Low (LC) Low (LC)<br />

DSM Interruptible Supply Expected (EI) Low (LI)<br />

Probability 0.1008 0.0672<br />

Futures <strong>Plan</strong> A-15 / Scenario 15 <strong>Plan</strong> A-16/ Scenario 16<br />

Load Forecast Expected (ED) High (HD)<br />

<strong>Plan</strong>t outage Expected (EF) High (HF)<br />

Capacity availability Low (LC) Expected (EC)<br />

DSM Interruptible Supply Expected (EI) Low (LI)<br />

Probability 0.0672 0.0432


Risk & Sensitivity Analysis<br />

It is necessary to state that after consultation with the various experts in their fields, that some of the expected<br />

events (used as basis for developing the NIRP2 Reference <strong>Plan</strong>) were in fact less realistic than originally<br />

thought. This resulted in some cases, higher probabilities being assigned to the alternative case than the<br />

expected case.<br />

5.Ranking of <strong>Plan</strong>s/Candidate <strong>Plan</strong>s<br />

The assessment of the plans/scenarios includes the following steps:<br />

& Development of optimal resource plan for each of the 16 scenarios;<br />

& Testing each of the plans under the assumptions of the remaining scenarios;<br />

& Calculation of the total probability weighted cost (PWC) of each plan;<br />

& Ranking of the plans in terms of the attributes<br />

& Selection of the most robust plan<br />

The output of the trade-off analyses would be the most robust optimum plan/strategy for capacity development<br />

over the planning period.<br />

The selected attributes (measures of goodness) for evaluation of the plans are:<br />

& Total probability weighted cost<br />

& Reliability<br />

& Emissions;<br />

& Diversity of fuel sources.<br />

5.1 Methodology<br />

51<br />

The main criteria for measuring the performance of the plans is the total probability-weighted cost (PWC). The<br />

probability-weighted cost is calculated as the sum of the total cost of the plan for each of the 16 scenarios<br />

multiplied by the probability of occurrence of the corresponding scenario.<br />

The 16 plans are ranked in ascending order (minimum cost) in terms of total probability-weighted cost (PWC).<br />

The first three plans with the lowest probability-weighted total cost are then selected as candidates for the<br />

preferred plan.<br />

In order to test the sensitivity of the probability-weighted cost to the length of planning period, these analyses<br />

were conducted for planning horizon of 8, 12, 16 and 20 years.<br />

To test the sensitivity of the probability weighted cost to the probability assigned to each of the primary<br />

uncertainties, i.e. the analyses were conducted for equal probability of each of the primary uncertainties (50%<br />

probability of occurrence of each of the primary uncertainties), as well as for 60% probability of occurrence of<br />

the expected uncertainties.<br />

The second attribute considered is the reliability of the plans measured as the level of the reserve margin<br />

provided by the plan over the planning horizon. Higher reserve margin will provide higher system adequacy<br />

and reliability. The candidate plans are ranked in descending order according to the RM they provide.<br />

The evaluation of the plans in terms of the emissions is conducted by comparing the total emission level (CO2,<br />

SO2, NO2 and particulate emissions) of the three candidate plans over the planning horizon.<br />

The fourth attribute for comparison is the diversity of the plans. The diversity of the plans is measured as the<br />

ratio of non-coal and coal based generation resources.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

5.2 Total Probability-Weighted Cost<br />

The ranking of the plans is conducted in terms of the attribute total probability weighted cost. The first three<br />

plans are selected as candidates for the most robust plan/strategy for implementation.<br />

The ranking of the 16 plans and their associated expectation cost over the whole planning period (20 years), 16<br />

years, 12 years and 8 years is illustrated in Table 6 below. While under the assumed probabilities of the<br />

primary uncertainties <strong>Plan</strong> 14 enjoys the least cost or most robust position, <strong>Plan</strong> 8 and <strong>Plan</strong> 16 follow closely its<br />

performance. The ranking of these three plans remains unchanged within a range of planning period from 12 to<br />

20 years.<br />

The ranking of the plans for the first 8 years indicates that the <strong>Plan</strong> 14 and <strong>Plan</strong> 08 maintain their position as the<br />

best performers while <strong>Plan</strong> 3 emerges as the second most robust plan for the first 8 years of the resource plan<br />

study period.<br />

Table 6: PWC Ranking of the <strong>Plan</strong>s<br />

Ranking of Expectation over<br />

<strong>Plan</strong>s over 8 8 years, mR<br />

years<br />

Ranking of <strong>Plan</strong>s<br />

over 12 years<br />

Expectation over<br />

12 years, mR<br />

Ranking of<br />

<strong>Plan</strong>s over 16<br />

years<br />

Expectation<br />

over 16 years,<br />

mR<br />

Ranking of<br />

<strong>Plan</strong>s over<br />

20 years<br />

Expectation<br />

over 20 years,<br />

mR<br />

52<br />

Assumed probabilities<br />

<strong>Plan</strong>14 102 651 <strong>Plan</strong>14 145 335 <strong>Plan</strong>14 181 830 <strong>Plan</strong>14 212 601<br />

<strong>Plan</strong>03 102 790 <strong>Plan</strong>08 145 712 <strong>Plan</strong>08 182 547 <strong>Plan</strong>08 214 053<br />

<strong>Plan</strong>08 102 872 <strong>Plan</strong>16 146 098 <strong>Plan</strong>16 183 084 <strong>Plan</strong>16 214 546<br />

50% Probabilities of primary uncertainties (Each plan has an equal probabilty of 6.25%)<br />

<strong>Plan</strong>14 102 267 <strong>Plan</strong>14 144 854 <strong>Plan</strong>14 181 364 <strong>Plan</strong>14 212 175<br />

<strong>Plan</strong>03 102 361 <strong>Plan</strong>08 145 250 <strong>Plan</strong>08 182 154 <strong>Plan</strong>08 213 722<br />

<strong>Plan</strong>08 102 379 <strong>Plan</strong>16 146 046 <strong>Plan</strong>12 183 077 <strong>Plan</strong>12 213 968<br />

60% Probablities of expected primary uncertainties (<strong>Plan</strong> A1 has the highest probability of 12.96%)<br />

<strong>Plan</strong>10 100 341 <strong>Plan</strong>10 141 587 <strong>Plan</strong>12 177 074 <strong>Plan</strong>12 207 187<br />

<strong>Plan</strong>12 100 341 <strong>Plan</strong>12 141 633 <strong>Plan</strong>10 177 122 <strong>Plan</strong>10 207 203<br />

<strong>Plan</strong>05 100 456 <strong>Plan</strong>14 141 780 <strong>Plan</strong>14 177 241 <strong>Plan</strong>14 207 444<br />

The above results show that the ranking of <strong>Plan</strong> 14 is not sensitive to small changes in the assigned<br />

probabilities and the length of the planning period.<br />

The difference in the PWC of the first three plans is marginal and less than 1%.<br />

The actual variability of the plans PV cost under the modeled future conditions is illustrated in Figure 5 below.<br />

For a comparison the graph also includes plan A2 which is developed for the most pessimistic conditions<br />

(highest capacity requirements) and therefore carries the least variability of the costs under the remaining 15<br />

more favorable futures.<br />

The performance of the first three plans, <strong>Plan</strong> 14, 08 and 16 is further evaluated in terms of the attributes<br />

reliability, emissions and diversity.


Risk & Sensitivity Analysis<br />

310 000<br />

290 000<br />

<strong>Plan</strong> 2 NPV 20<br />

<strong>Plan</strong> 3 NPV 20<br />

<strong>Plan</strong> 8 NPV 20<br />

<strong>Plan</strong> 14 NPV 20<br />

<strong>Plan</strong> 16 NPV 20<br />

Total cost, mR<br />

270 000<br />

250 000<br />

230 000<br />

210 000<br />

190 000<br />

S01 S02 S03 S04 S05 S06 S07 S08 S09 S10 S11 S12 S13 S14 S15 S16<br />

Scenario<br />

Figure 5: Variability of total cost.<br />

5.3 Reliability Assessment<br />

The reliability assessment is conducted in terms of the reserve margin carried by the plans under the future<br />

scenario they were developed for and the reserve margin that the plans would carry had the expected<br />

conditions (business as usual) prevailed over the planning period. The reserve margin under own future and<br />

under the expected (A1) future are shown in Figure 6 and Figure 7, respectively.<br />

25.00%<br />

53<br />

RM, %<br />

20.00%<br />

15.00%<br />

A3<br />

A14<br />

A16<br />

A8<br />

10.00%<br />

5.00%<br />

0.00%<br />

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

Year<br />

Figure 6: Reserve Margin under own future.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

25.00%<br />

20.00%<br />

A3<br />

A14<br />

A16<br />

A8<br />

RM, %<br />

15.00%<br />

10.00%<br />

5.00%<br />

0.00%<br />

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

Year<br />

Figure 7: Reserve Margin under A1 future.<br />

<strong>Plan</strong> 14 carries a higher than 10% reserve margin (RM) under its own future from 2008 to 2022 and 12% % RM<br />

under expected future (A1). In comparison <strong>Plan</strong> 16 carries a better RM under A1 future but under its own future<br />

scenario its RM is relatively low.<br />

5.4 Emissions and Diversification Assessment<br />

54<br />

A summary of the comparison of the plans in terms of diversity of resources, emissions as well as costs and<br />

reliability parameters is provided in Table 7 overleaf.<br />

In terms of emissions the least-cost candidate plans have quite similar performance. This is a result of the large<br />

share of the coal-fired generation in all 16 plans. For the same reason the diversification of the plans is also low<br />

and varies between 9 and 12%. However, regardless of the close performance of the plans in terms of<br />

emissions, <strong>Plan</strong> 3 ranks marginally as the plan with the lowest emissions level, followed by the remaining three<br />

plans with almost equal pollution level.<br />

Higher diversification of resource is achieved in the alternative of the <strong>Plan</strong> 14, presented hereafter, which<br />

factors the Government renewable energy (RE) target of 10 000 GWh by 2012 in the capacity mix.


Risk & Sensitivity Analysis<br />

Table 7: Comparison of Candidate <strong>Plan</strong>s<br />

NIRP 2 STAGE 2 COMPARISON OF CANDIDATE PLANS<br />

<strong>Plan</strong> A14 A8 A16 A3<br />

Probability 0.0672 0.0288 0.0432 0.1512<br />

Demand High High High E<br />

FOR E High High high<br />

Capacity Avail Low E E Low<br />

DSM IL Low E Low Low<br />

RM(weighted average 2006-2022) 10.61% 6.85% 6.23% 8.90%<br />

RM(weighted average 2006-2022) under Ref<br />

case A1 14.53% 16.57% 17.70% 12.80%<br />

LOLP (average over 20 yrs) 0.00514 0.0054066 0.007379 0.00568<br />

USE (over 20yrs), GWh 919 940 1307 888<br />

Probability weighted PV cost over 20yrs, mR 212 601 214 053 214 546 216 969<br />

Probability weighted PV cost over 20yrs, % 100.00% 100.68% 100.91% 102.05%<br />

PV System Cost, mR 209 169 221 189 230 200 202 638<br />

PV of Capex, mR 61 009 69 261 70 534 58553<br />

PV of Energy Prod (20 yrs) GWh 2 455 643 2 545 521 2 545 268 2 455 613<br />

Constant cost, R/KWh 0.0852 0.0869 0.0904 0.0825<br />

Constant pobability weighted cost, R/KWh 0.0866 0.0841 0.0843 0.0884<br />

New capacity, MW<br />

Mothballed plants, MW 3559 3559 3559 3559<br />

First unit year 2005 2005 2005 2005<br />

OCGT(peak), MW 2880 2880 3360 1920<br />

First unit year 2 006 2 006 2 006 2006<br />

Pump Storage (peak), MW 3330 3330 3330 3330<br />

First unit year 2 012 2 012 2 012 2012<br />

CCGT (base load), MW - - - -<br />

First unit year - - - -<br />

PF(base load), MW 9630 10914 11556 10272<br />

First unit year 2016 2015 2015 2015<br />

FBC (base load), MW 2330 2796 2330 1398<br />

First unit year 2012 2010 2010 2010<br />

Total capacity MW 21 729 23 479 24 135 20 479<br />

PV of Capex, mR 61 009 69 261 70 534 58553<br />

Coal based, % 86.75% 87.73% 86.08% 90.62%<br />

Diversity (non-coal), % 13.25% 12.27% 13.92% 9.38%<br />

55<br />

CO2 Emissions (Mt) 5397 5340 5336 5180<br />

SO2 Emissions (Mt) 47 47 46 44<br />

NO2 Emissions (Mt) 20 20 20 19<br />

Particulate Emissions (Mt) 1 1 1 1<br />

Water Usage (Mcub m) 7232 7028 7034 6951<br />

Total emissions, Mt 5464 5407 5402 5243


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

6.Preferred <strong>Resource</strong> <strong>Plan</strong><br />

The overall ranking of the plans is conducted in terms of the attributes PWC, RM own, diversity and emissions<br />

with a weighting of 40, 40, 10 and 10% respectively. Sensitivity analyses are performed with weightings of<br />

30/30/20/20 and 50/30/10/10. The results of the ranking of the plans are illustrated in Figure 8 below.<br />

1.100<br />

1.000<br />

0.900<br />

Best plan =1<br />

A14<br />

A3<br />

A8<br />

A16<br />

0.800<br />

0.700<br />

0.600<br />

0.500<br />

0.400<br />

RM own Prob Weighted PV Emmissions Diversity Weight 40/40/10/10 Weight 30/30/20/20 Weight 50/30/10/10<br />

Figure 8: Ranking of <strong>Plan</strong>s<br />

56<br />

<strong>Plan</strong> 14 remains the most robust plan, followed by <strong>Plan</strong> 3, plan 8 and <strong>Plan</strong> 16. Therefore in terms of the<br />

attributes <strong>Plan</strong> 14 should be selected as the optimum most robust plan/strategy for implementation. It has to be<br />

highlighted that the four candidate plans are very similar regarding the capacity mix and timing. All plans,<br />

except <strong>Plan</strong> 3 are developed for high growth scenario which is the planning uncertainty with the highest impact<br />

on the future capacity requirements, timing and capacity mix.<br />

The preferred <strong>Plan</strong> 14 is developed under high growth demand forecast, expected plant outage rate, low<br />

import and municipal capacity availability and no interruptible loads.<br />

6.1 Preferred <strong>Plan</strong> 14<br />

The capacity mix and timing of <strong>Plan</strong> 14 are shown in Table 8. Details about <strong>Plan</strong> 14 attributes are illustrated in<br />

Table 5.2.<br />

Similarly to the remaining 15 plans, <strong>Plan</strong> 14 is also based on RTS of all mothballed plants by the year 2011.<br />

In terms of peaking plants, the plan requires construction of 2880 MW of OCGTs starting from the year 2006 to<br />

meet the medium term requirements for peaking capacity. The peaking requirements in the second half of the<br />

planning period are satisfied by the commissioning of 3330 MW of pump-storage plants starting from the year<br />

2012.<br />

The first FBC base-load capacity is required in 2012 while the first PF coal-fired unit must be commissioned in<br />

2016.<br />

The plan provides certain degree of flexibility regarding modification of the timing of the required capacity.<br />

Depending on deviations of the actual demand from the forecasted, the decisions for resource commissioning<br />

could be accelerated or delayed.


Risk & Sensitivity Analysis<br />

Table 8: Preferred <strong>Plan</strong> 14.<br />

Mothballed Coal-Fired FBC Gas Pumped Storage DSM<br />

YR Cam (PF) Gr'tvlei<br />

(PF)<br />

Kom (PF) PF (1) PF (2) PF (3) Green-field<br />

FBC<br />

OCGT PS (A) PS (B) PS (C) CEE IMEE<br />

IMLM REE<br />

RLM<br />

Reserve on<br />

moderate<br />

forecast<br />

Committed Committed Committed<br />

2003 Committed Committed Decide 152 24%<br />

2004 Decide Decide 152 21%<br />

2005 380 Decide 152 18%<br />

2006 380 720 152 17%<br />

2007 570 188 152 16%<br />

2008 190 377 101 Decide 480 152 16%<br />

2009 565 202 Decide 720 Decide 152 17%<br />

2010 303 720 152 17%<br />

2011 303 152 13%<br />

2012 932 333 13%<br />

2013 466 999 13%<br />

2014 932 999 15%<br />

2015 13%<br />

2016 1284 13%<br />

2017 1284 14%<br />

2018 1284 14%<br />

2019 999 14%<br />

2020 1284 15%<br />

2021 1284 642 14%<br />

2022 1284 1284 240 13%<br />

TOTAL 1520 1130 909 3852 3852 1926 2330 2880 1332 999 999 1370<br />

7.Sensitivity Analysis<br />

The ARC requested the following sensitivities be investigated:<br />

& The impact of the net discount rate on the optimum choice of technology;<br />

& The impact of Renewable Energy Technologies on the preferred (robust) plan;<br />

57<br />

These sensitivity studies were considered necessary to test the robustness of the conclusions and<br />

recommendations emanating from the NIRP2 Reference <strong>Plan</strong>, and their impact on important energy policy<br />

issues.<br />

Before discussing the sensitivity analysis it is necessary to highlight data changes made to the demand- and<br />

supply-side data base of the NIRP2 Reference <strong>Plan</strong> in this study.<br />

A summary of the complete data base of new plant capital, O&M, Fuel costs and performance parameters is<br />

given in Appendix C of this Report<br />

7.1 Comparison of Data changes to NIRP2 Reference <strong>Plan</strong><br />

No data changes were made to any existing plant options or new demand-side initiatives from the NIRP2<br />

Reference <strong>Plan</strong>. Marginal changes were made to some specific new supply-side options. To highlight these<br />

changes more effectively, the candidate plants are separated into Peaking and Base Load options.<br />

These options are compared in terms of their levelised costs at their maximum production levels and<br />

separated into O&M, Fuel and Capex components. It is important to note that the CCGT option in the Cape<br />

using natural gas was excluded from the analysis in this Report. However this was replaced with a CCGT plant<br />

(located in Namibia) using natural gas from the Kudu field.<br />

The results in Figure 9, Figure 10 and Figure 11 below, show that the most significant changes were made to<br />

the cost of coal. There is an increase in coal costs in the case of the PF plants and an increase in O&M cost for<br />

new FBC options to account for an increased requirement for sorbent.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Comparison of Change in Cost at 10% NDR between the Reference NIRP2 <strong>Plan</strong> and the<br />

Risk & Sensitivity <strong>Plan</strong><br />

400.00<br />

Reference <strong>Plan</strong> <strong>Plan</strong>t Capex<br />

Risk & Sensitivity <strong>Plan</strong>t Capex<br />

360.00<br />

320.00<br />

CAPEX R /MWh<br />

280.00<br />

240.00<br />

200.00<br />

160.00<br />

120.00<br />

80.00<br />

40.00<br />

0.00<br />

CF with FGD<br />

Greenfield FBC<br />

with FGD<br />

CCGT Incl Trans<br />

(LNG)<br />

CCGT Kudu<br />

(Offshore nat gas)<br />

CCGT Incl Trans<br />

(pipe)<br />

Mepanda Uncua<br />

<strong>PBMR</strong> (1st MM<br />

Incl trans)<br />

PWR (Incl trans<br />

benefits)<br />

Figure 9: Capex Costs for Base Options<br />

58<br />

Comparison of Change in Cost at 10% NDR between the Reference NIRP2 <strong>Plan</strong> and the<br />

Risk & Sensitivity <strong>Plan</strong><br />

Reference O & M Cost<br />

60.00<br />

Risk & Sensitivity O & M Cost<br />

CAPEX R /MWh<br />

40.00<br />

20.00<br />

0.00<br />

CF with FGD<br />

Greenfield FBC<br />

with FGD<br />

CCGT Incl Trans<br />

(LNG)<br />

CCGT Kudu<br />

(Offshore nat gas)<br />

CCGT Incl Trans<br />

(pipe)<br />

Mepanda Uncua<br />

<strong>PBMR</strong> (1st MM<br />

Incl trans)<br />

PWR (Incl trans<br />

benefits)<br />

Figure 10: O&M Costs for NIRP 2 Reference <strong>Plan</strong> and NIRP 2 Risk & Sensitivity <strong>Plan</strong>


Risk & Sensitivity Analysis<br />

Comparison of Change in Cost at 10% NDR between the Reference NIRP2 <strong>Plan</strong> and the<br />

Risk & Sensitivity <strong>Plan</strong><br />

Reference Fuel Working Cost<br />

Risk & Sensitivity Fuel Working Cost<br />

200.00<br />

CAPEX R /MWh<br />

150.00<br />

100.00<br />

50.00<br />

0.00<br />

CF with FGD<br />

Greenfield FBC<br />

with FGD<br />

CCGT Incl Trans<br />

(LNG)<br />

CCGT Kudu<br />

(Offshore nat gas)<br />

CCGT Incl Trans<br />

(pipe)<br />

Mepanda Uncua<br />

<strong>PBMR</strong> (1st MM<br />

Incl trans)<br />

PWR (Incl trans<br />

benefits)<br />

Figure 11: Fuel Costs for NIRP 2 Reference <strong>Plan</strong> and NIRP 2 Risk & Sensitivity <strong>Plan</strong><br />

7.2 The impact of net discount rate on optimum choice of technology<br />

59<br />

The timing of building new plant options will not be impacted to any great extent by small changes to the net<br />

discount rate. However changes to the net discount rate will impact on which base-load and peaking<br />

technologies are selected in the plant mix.<br />

Due to time constraints required to prepare sets of plans for different net discount rates, it was agreed by the<br />

ARC to carry out this analysis, external to the computer modelling process, by studying the impact of different<br />

net discount rates on the life-cycle levelised costs of building and operating the specific plant options.<br />

The analysis is carried out on both the data as detailed in the NIRP2 Reference <strong>Plan</strong> database as well as for the<br />

updated costs as applied in the database for this study. Where applicable, differences between the two sets of<br />

data are highlighted.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

Table 9 below shows the impact of changes in the net discount rate on the life-cycle levelised costs of all the<br />

options available to the NIRP2 Reference <strong>Plan</strong> at their maximum operating levels.<br />

Table 9: Levelised costs of candidates for selection in the NIRP2 Reference <strong>Plan</strong><br />

NIRP 2 Reference <strong>Plan</strong> Options Load Factor<br />

Net Discount Rate<br />

4.0% 6.0% 8.0% 10.0% 12.0% 14.0% 16.0%<br />

PF with FGD 88% 137.4 160.1 185.6 214.0 244.7 277.7 312.7<br />

PF without FGD 88% 127.5 148.3 171.7 197.6 225.8 256.0 288.1<br />

Greenfield FBC without FGD 86% 131.7 153.0 176.9 202.9 230.8 260.5 291.5<br />

Greenfield FBC with FGD 86% 134.2 155.3 179.0 205.0 232.9 262.5 293.5<br />

CCGT Incl Trans (LNG) 85% 310.7 318.7 327.6 337.1 347.2 357.8 368.7<br />

CCGT Excl Trans (LNG) 85% 328.1 337.4 347.6 358.6 370.3 382.5 395.0<br />

Single cycle GT (kerosine) 13% 1158.3 1199.8 1244.3 1291.3 1340.0 1389.8 1440.2<br />

Single cycle GT (LNG) 13% 706.9 749.5 795.1 843.0 892.5 943.0 994.2<br />

Single cycle GT (local syngas) 13% 663.3 706.3 752.3 800.6 850.5 901.4 952.9<br />

Single cycle GT (LPG) 13% 1005.8 1047.7 1092.6 1139.9 1188.8 1238.9 1289.5<br />

CCGT Incl Trans (pipe) 85% 219.5 227.7 236.7 246.4 256.5 267.2 278.1<br />

CCGT Excl Trans (pipe) 85% 234.8 244.3 254.7 265.8 277.5 289.8 302.4<br />

PS (based on Braamhoek public data) 23% 185.2 225.3 275.2 335.4 406.6 489.5 585.4<br />

PS (generic) 20% 269.1 348.9 448.2 568.1 710.0 875.5 1066.8<br />

Mepanda Uncua 58% 242.3 303.9 375.4 456.5 547.4 647.8 758.0<br />

Wind 33% 256.0 292.6 331.9 373.8 417.9 463.9 511.4<br />

Concentrating Solar Power 70% 336.6 409.2 486.3 566.0 646.9 728.0 808.3<br />

<strong>PBMR</strong> (1st MM incl. trans) 86% 187.7 220.6 258.3 299.9 344.9 392.8 443.4<br />

<strong>PBMR</strong> (1st MM excl. trans) 86% 206.6 244.0 286.7 334.0 385.0 439.4 496.7<br />

<strong>PBMR</strong> (Series MM excl. trans) 88% 154.7 174.7 197.7 223.1 250.5 279.7 310.4<br />

PWR (inc trans benefits) 79% 236.9 268.4 303.5 341.2 380.8 421.9 464.1<br />

PWR (exc trans benefits) 79% 248.6 280.4 315.7 353.8 393.8 435.3 477.9<br />

60<br />

Table 10 below shows the impact of changes in the net discount rate on the life-cycle levelised costs of all the<br />

options available in this study also at their maximum operating levels.<br />

Table 10: Levelised costs of candidates for selection for the NIRP2 Risk and Sensitivity Analysis<br />

NIRP 2 Risk and Sensitivity <strong>Plan</strong> Options Load Factor<br />

Net Discount Rate<br />

4.0% 6.0% 8.0% 10.0% 12.0% 14.0% 16.0%<br />

PF with FGD 88% 145.6 167.9 193.2 221.1 251.5 284.1 318.7<br />

PF without FGD 88% 136.0 156.4 179.6 205.1 233.0 262.8 294.5<br />

Greenfield FBC without FGD 86% 134.8 156.1 179.9 206.0 233.9 263.6 294.7<br />

Greenfield FBC with FGD 86% 150.2 171.8 195.9 222.1 250.2 279.9 311.1<br />

CCGT Incl Trans (LNG) 85% 308.0 315.9 324.6 334.0 343.9 354.3 365.1<br />

CCGT Excl Trans (LNG) 85% 320.4 329.5 339.5 350.3 361.7 373.6 385.9<br />

Single cycle GT (kerosine) 13% 1158.3 1199.8 1244.3 1291.3 1340.0 1389.8 1440.2<br />

Single cycle GT (LNG) 13% 706.9 749.5 795.1 843.0 892.5 943.0 994.2<br />

Single cycle GT (local syngas) 13% 663.3 706.3 752.3 800.6 850.5 901.4 952.9<br />

Single cycle GT (LPG) 13% 1005.8 1047.7 1092.6 1139.9 1188.8 1238.9 1289.5<br />

CCGT Kudu (Offshore nat gas) 85% 228.8 238.4 249.0 260.4 272.5 285.1 298.2<br />

PS (based on Braamhoek public data) 23% 193.7 233.8 283.7 343.8 415.0 498.0 593.8<br />

PS (generic) 20% 277.6 357.4 456.7 576.6 718.5 884.0 1075.2<br />

Mepanda Uncua 58% 216.0 280.6 355.8 440.8 535.1 638.5 751.1<br />

Wind 33% 251.1 281.9 314.3 347.7 381.9 416.5 451.3<br />

Concentrating Solar Power 70% 492.6 565.2 642.3 722.1 803.1 884.2 964.5<br />

<strong>PBMR</strong> (1st MM incl. trans) 92% 168.6 199.3 233.7 271.0 310.4 351.6 394.2<br />

<strong>PBMR</strong> (1st MM excl. trans) 92% 183.8 218.7 257.7 299.9 344.7 391.4 439.7<br />

<strong>PBMR</strong> (Series MM excl. trans) 94% 124.3 143.0 163.9 186.7 210.8 235.9 261.8<br />

PWR (inc trans benefits) 79% 239.3 270.8 305.8 343.6 383.2 424.3 466.4<br />

PWR (exc trans benefits) 79% 255.4 287.1 322.5 360.6 400.6 442.1 484.6<br />

Due to the levelised cost being sensitive to the load factor applied, the following analyses focus on the<br />

candidate base-load technologies taken at their maximum operating levels.


Risk & Sensitivity Analysis<br />

Selected plots for the various options based on type can be revealing. The base-load options with transmission<br />

credits, referenced against a coal-fired plant are illustrated in Figure 12 and Figure 13 below for both the NIRP2<br />

Reference <strong>Plan</strong> and this study. Options with a high capital component become less attractive with the increase<br />

in net discount rate. The reverse is true at lower discount rates.<br />

Life cycle levelised cost (R/MWh) to build and operate new plant - NIRP2 Reference plan<br />

Cost of Supply (R/MWh)<br />

500.0<br />

450.0<br />

400.0<br />

350.0<br />

300.0<br />

250.0<br />

200.0<br />

150.0<br />

PWR (inc trans benefits)<br />

CCGT Incl Trans (LNG)<br />

<strong>PBMR</strong> (1st MM incl. trans)<br />

CCGT Incl Trans (pipe)<br />

PF with FGD<br />

Greenfield FBC with FGD<br />

100.0<br />

50.0<br />

0.0<br />

4.0% 6.0% 8.0% 10.0% 12.0% 14.0% 16.0%<br />

Real Discount Rate (%)<br />

Figure 12: Levelised costs of base-load plants vs Net Discount Rate for the NIRP 2 Reference <strong>Plan</strong><br />

61<br />

Sensitivity of Levelised Lifecycle costs of <strong>Plan</strong>t to Net Discount Rate - NIRP2 Risk & Sensitivity<br />

Analysis<br />

Cost of Supply (R/MWh)<br />

500.0<br />

450.0<br />

400.0<br />

350.0<br />

300.0<br />

250.0<br />

200.0<br />

150.0<br />

PWR (inc trans benefits)<br />

CCGT Incl Trans (LNG)<br />

<strong>PBMR</strong> (1st MM incl. trans)<br />

CCGT Kudu (Offshore nat gas)<br />

PF with FGD<br />

Greenfield FBC with FGD<br />

100.0<br />

50.0<br />

0.0<br />

4.0% 6.0% 8.0% 10.0% 12.0% 14.0% 16.0%<br />

Real Discount Rate (%)<br />

Figure 13: Levelised costs of base-load plants vs Net Discount Rate for the NIRP 2 Risk &<br />

Sensitivity Analysis


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

7.3 Renewable Energy Technologies<br />

The levelised costs of renewable technologies (wind and concentrating solar power) are relatively high when<br />

compared to other equivalent supply options operating at similar levels of production. Because of this high cost<br />

in building renewable energy technologies, the computed economic least cost optimisation process excludes<br />

these options from the planning base.<br />

However, it is difficult to assess the externality benefits of these options in a purely economic comparison and it<br />

is stated Government policy to introduce some amount of renewable technologies in the Electricity Supply<br />

planning base.<br />

For purposes of this study, and to try and meet the aspirations of Government policy (10000GWh cumulative<br />

energy supplied by renewable energy sources (RES) wind, solar, biomass, small-scale hydro by 2013), two of<br />

the technologies; wind and concentrating solar power (CSP), are considered in this analysis only due to the<br />

lack of reliable data for other RES. It has to be underlined that the selected RES mix is not the least cost mix. A<br />

number of lower cost RES options have been identified by the White Paper on Renewable Energy (WPRE)<br />

and currently under investigation for implementation.<br />

The lead-time required to engineer, design and build these options is stated as 2 years for wind, and 3 years for<br />

CSP. This excludes EIA's, licensing, financing and other issues. For the purpose of this study and to be able to<br />

meet Government aspirations, wind turbines (20MW total) are brought into commercial service in 2007,<br />

expected to achieve a maximum load factor of at least 30% annually. CSP (300MW total), is anticipated to<br />

operate at a load factor of at least 70% (with battery assistance) are introduced from 2008.<br />

62<br />

The additional cost of imposing renewable technologies on the system and the cumulative energy contribution<br />

can be seen in Table 11 below.<br />

Table 11: Additional Cost of Renewable Technologies<br />

Capex (Rm)<br />

O & M Costs<br />

Total<br />

PV Cost (Rm)<br />

Total Energy SO<br />

(Rm)<br />

cost of<br />

of<br />

(GWh)<br />

Wind &<br />

Renewables<br />

Solar<br />

Year Wind Solar Wind Solar (Rm) Total Cum. Annual Cum.<br />

2003<br />

2004<br />

2005<br />

2006<br />

2007 155 4 159 109 109 57 57<br />

2008 10377 4 337 10717 6655 6763 1935 1992<br />

2009 4 337 341 192 6955 1935 3927<br />

2010 4 337 341 175 7130 1935 5862<br />

2011 4 337 341 159 7289 1935 7797<br />

2012 4 337 341 144 7434 1935 9732<br />

2013 4 337 341 131 7565 1935 11667<br />

2014 4 337 341 119 7684 1935 13602<br />

2015 4 337 341 109 7793 1935 15537<br />

2016 4 337 341 99 7892 1935 17472<br />

2017 4 337 341 90 7981 1935 19407<br />

2018 4 337 341 82 8063 1935 21342<br />

2019 4 337 341 74 8137 1935 23277<br />

2020 4 337 341 67 8204 1935 25212<br />

2021 4 337 341 61 8266 1935 27147<br />

2022 4 337 341 56 8321 1935 29082<br />

These results show the high cost of the solar contribution to the total additional cost of these two renewable<br />

technologies. The overall increase in cost to the system from implementing these options is estimated by<br />

carrying out a detailed computational analysis on the preferred plan 14.


Risk & Sensitivity Analysis<br />

The power supply profiles of these options will not always be consistent with the system demand profile. These<br />

options are therefore modelled as non-dispatchable technologies. A power demand profile for the wind option<br />

was supplied by ERC in consultation and assistance from the Darling Wind Farm IPP in the Western Cape, to<br />

yield a load factor of 33%.<br />

The profile for the CSP was assumed to be similar to that of the commercial and industrial energy efficiency<br />

programmes yielding a load factor of 71%. These profiles were used to simulate the required load factor<br />

expectations of these renewable options.<br />

The results of the computational analysis show an increase in PV cost of R4773 Million cumulative over the<br />

planning horizon compared to the preferred <strong>Plan</strong> 14 without renewables, as illustrated in Figure 14 below.<br />

Mothballed Coal-Fired FBC Gas Pumped Storage Renewables DSM<br />

YR Cam (PF) Gr'tvlei<br />

(PF)<br />

Kom (PF) PF (1) PF (2) PF (3) Green-field<br />

FBC<br />

OCGT PS (A) PS (B) PS (C) Conc.<br />

Solar<br />

Panels<br />

(CSP)<br />

Wind<br />

Turbines<br />

CEE IMEE<br />

IMLM REE<br />

RLM<br />

Committed Committed Committed<br />

2003 Committed Committed Decide 152<br />

2004 Decide Decide Decide Decide 152<br />

2005 380 Decide 152<br />

2006 380 720 152<br />

2007 570 188 20 152<br />

2008 190 377 101 Decide 240 300 152<br />

2009 565 202 720 152<br />

2010 303 Decide 720 152<br />

2011 303 240 Decide 152<br />

2012 932 333<br />

2013 999<br />

2014 932 999<br />

2015 466<br />

2016 1284<br />

2017 1284<br />

2018 1284<br />

2019<br />

2020 1284<br />

2021 1284 466 999<br />

2022 1284 1284<br />

TOTAL 1520 1130 909 3852 3852 1284 2796 2640 1332 999 999 300 20 1370<br />

63<br />

Figure 14: Preferred <strong>Plan</strong> 14 with Renewables<br />

The renewable options will reduce environmental emissions and water consumption of the preferred <strong>Plan</strong>14.<br />

The extent to which the renewables reduce the environmental emissions is illustrated in Figure 15 below.<br />

CO 2 MTons<br />

30<br />

25<br />

20<br />

Cum CO2 Reduced Emissions<br />

Cum SO2 Reduced Emissions<br />

Cum Reduced NO2 Emissions<br />

Cum Reduced Part Emissions<br />

MTons { SO 2 , Particulates<br />

& NO 2 Emmisions}<br />

0.3<br />

0.25<br />

0.2<br />

15<br />

0.15<br />

10<br />

0.1<br />

5<br />

0.05<br />

0<br />

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022<br />

Years<br />

Figure 15: Reduction in environment emissions in preferred <strong>Plan</strong> 14 with renewables.<br />

0


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2<br />

The cumulative total emission reduction of CO2 over the planning horizon is 28.2 Million Tons whereas the<br />

cumulative constant rand increase in the cost of the plan is R13547 Million. This represents a cost of R481/Ton<br />

of CO2 saved at 1 January 2003 prices.<br />

8.Conclusions<br />

The main conclusions of these studies in comparison with the NIRP2 reference are summarised as follows:<br />

64<br />

1) The preferred plan has been developed on the basis of an evaluation of risk profiles and the reserve<br />

margin is an outcome of the optimisation process.<br />

2) The reserve margin of the preferred plan is higher than the 10% reserve margin used as a deterministic<br />

reliability criteria in the reference plan;<br />

3) The studies show that immediate decisions are required for peaking and base load plants from 2006 and<br />

2012 respectively;<br />

4) The base load plants competing for commercial operation from 2012 competing, include; Pulverised Fuel<br />

Coal-fired (PF); Fluidised Bed Combustion (FBC); Combined Cycle Gas Turbine (CCGT)<br />

5) In order to meet Government RES targets by 2013 immediate decisions are also required for renewable<br />

energy options;<br />

6) Options for diversification are still insufficient to meet all of the forecast demand for electricity over the next<br />

20-year planning horizon. Coal-fired options are still predominating the capacity during the 20-year<br />

planning horizon. For environmental benefit it is imperative to continue with efforts to reduce the costs of<br />

implementing clean coal technologies and improve the efficiency of coal-fired plants;<br />

7) At the current assumed cost of capital (10% net discount rate before tax) and after returning the Eskom<br />

mothballed plant to service, fluidised bed combustion technologies are South Africa's most economic<br />

option, followed by investment in coal-fired plant. This in turn is followed by importing gas / LNG for CCGT<br />

plant in the Cape;<br />

8) It will be difficult to justify diversification on an economic basis, unless penalties for not doing so are<br />

included in future analyses. As the cost for diversification is becoming increasingly more expensive these<br />

penalties (or opportunities for emissions trading) will need to be substantial to offset the economic benefits<br />

of remaining with coal;<br />

9) The NIRP2 Stage 2 plans are based on the accepted RTS program of the mothballed plants;<br />

10) The preferred plan indicates that 2880 MW OCGT peaking plants are required in the planning horizon in<br />

service from 2006;<br />

11) There are supply options that have not been considered such as co-generation in industry, converting<br />

OCGT to CCGT, adding units onto existing power stations and new imports resulting from the<br />

development of Electricity Supply in the Southern African region;<br />

12) The RES scenario is not fully reflective of the least cost RES mix currently investigated for implementation<br />

of the WPRE. This will be included in the next round of the NIRP update.<br />

13) Should interruptible supply and / or OCGT capacity not be implemented this will significantly advance new<br />

base-load capacity;<br />

9.Appendices<br />

Appendix A: Summary of comments on reference case report<br />

Appendix B: Detailed <strong>Plan</strong>s<br />

Appendix C: Data Base


ARC and Public Comments on NIRP2 Reference Case<br />

Appendix A<br />

ARC AND PUBLIC COMMENTS ON THE NIRP2 REFERENCE CASE<br />

I. ESKOM SYSTEM OPERATION COMMENTS 66<br />

II. ESKOM KSACS COMMENT 67<br />

III. EIUG COMMENT ON NIRP 2003/4 REFERENCE CASE VERSION 18 DECEMBER 2003 70<br />

IV. ESKOM GENERATION COMMENTS ON NIRP 2003/4 REFERENCE CASE<br />

VERSION 18 DECEMBER 2003 72<br />

V. COMMENTS FROM DARLING IPP 74<br />

VI. COMMENTS FROM KELVIN IPP 75<br />

65


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix A<br />

I<br />

I. ESKOM SYSTEM OPERATION COMMENTS<br />

Provided by Mr. Michael Barry<br />

1. The method to use pre-defined reserve margins and then derive the generation expansion plan is not<br />

ideal. As mentioned in the ARC meetings, I believe a set of data assumptions should be defined and used<br />

in the modeling. The reserve margin is then an outcome of the modeling process. Using this approach,<br />

one can relate each generation expansion plan to a set of assumptions, for example with x% reduction in<br />

generation performance, the expansion plan is advanced by y years. This set of assumptions is changed<br />

for the various sensitivity studies/scenarios.<br />

2. The NIRP Reference <strong>Plan</strong> is for the forecast moderate load growth. (The documentation makes mention of<br />

robust plans, no regret and flexibility, but from my understanding these are not specifically considered in<br />

deriving the reference plan). The Reference <strong>Plan</strong> then gives a conservative picture (building too late)<br />

when one considers the load growth uncertainty and the cost of supplied vs unsupplied electricty. The<br />

Reference <strong>Plan</strong> should, as part of the set of assumptions, include an additional plant margin for load<br />

growth uncertainty.<br />

3. The NIRP Reference <strong>Plan</strong> does not make provision for the inherent inertia in changing the "direction" of a<br />

"ship" the size of the electricity industry in South Africa. The country is used to many years of no significant<br />

generation capacity expansion. The Reference <strong>Plan</strong> should, as part of the set of assumptions, include an<br />

additional plant margin for this inertia.<br />

66<br />

4. The Conclusions contain a number of "immediately implement" statements when referring to specific<br />

capacity additions. Is the NIRP saying a period of capacity shortages is forthcoming (and even more so<br />

considering the comments above)? If this is the case, should the NIRP not make some clear statement<br />

about the desirability of any capacity expansion or demand management in the next few years.<br />

5. From a strategic perspective, I believe a NIRP resulting in a reserve margin of anything less than 12% will<br />

harm the economy of South Africa. Potential international investors in the industrial arena might think<br />

"electricity interruptions" when seeing future reserve margins of less than 12%. Should the strategy not<br />

rather be to establish the capacity thereby stimulating highe growth?<br />

6. The reserve margin is calculated after the peak demand is reduced by the interruptible load. This implies a<br />

NIRP planning to interrupt customers. Is this the correct message?


ARC and Public Comments on NIRP2 Reference Case<br />

II<br />

II.ESKOM KSACS COMMENT<br />

Provided by Dr. Jean Pabot<br />

With respect to SAPP, I did not find this word in your report, though you mention briefly an option for imported<br />

hydro (Table 6). This option is not even discussed in the text (e.g. in Section 5). I assume you included the<br />

transmission costs from the foreign plant to the Eskom network into your capital cost. However this option<br />

appears not to have been considered in your simulations? If true, why?<br />

I accept that there are no good recent reliable data for SAPP hydro plants, except maybe for Mepanda Uncua,<br />

which may be the option mentioned inTable 6. If this is the case, it should be stated.<br />

You might consider a scenario where both Mepanda Uncua and Inga 3 are built, e.g. in 2014, irrespective of<br />

their costs, and study the impact thereof on your NIERP.<br />

There is some confusing wording and apparently an inconsistency about imports-exports in Section 3.6 and<br />

Section 5.1 (last 3 lines). Were exports included in the load forecast or not?<br />

It would be useful to include a table showing the MW exports included in the load forecast. It might already be in<br />

the appendices, but I did not see it.<br />

With respect to the reserve margins used in the SAPP studies, these are:<br />

We use:<br />

& 7,6 % for hydro units,<br />

& 10,6 % for thermal units,<br />

67<br />

There is a problem, even in Eskom, to justify a 10 % capacity reserve criterion to auditors, when many<br />

utilities have reserve criteria ranging from 15 % to 25 %.<br />

The minimum (or optimal) reserve margin is utility dependent. It depends on:<br />

& The risks which the utiity wants to mitigate by adding reserve capacity, e.g risks associated with uncertainties<br />

on plant availability, load forecast, fuel availability, etc.<br />

& The characteristics of the existing and future plants, e.g. unit size, plant availability, etc.<br />

& The costs involved, e.g. plant cost, cost of un-served energy, etc.<br />

Eskom is a SAPP member. A few years ago, the SAPP reduced its minimum installed capacity reserve<br />

requirements (not the operating reserve requirements) to about 10 %, based on the results of a simple<br />

optimization study. The methodology and assumptions are auditable, though auditors might disagree with all.<br />

With hindsight, I now believe that one of the drought related assumptions is not valid, but this would have little<br />

impact on thermal plant based utilities.<br />

Additional minor comments on your report:<br />

1. Interruptible supplies:<br />

& In section 5.2, the report states: there is a total 1510 MW interruptible supply capacity included in the plan.<br />

Does this mean that you have 1510 MW of interruptible load/supplies assumed to be equivalent to 1510 MW


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix A<br />

of supply capacity? or is this 2500 MW or 3000 MW of interruptible load/supplies assumed to be equivalent<br />

to 1510 MW of supply capacity? Table 1 in Appendix 1 mentions it is derated capacity. This should be<br />

explained in the text.<br />

& Table 2 in Appendix 2 shows that the existing interruptible load (IL) decreases from 1510 MW to 500 MW in<br />

2012 and 384 MW and that it is not replaced by new IL. This does not make much sense.<br />

& IL is a very cost effective way to provide reserve to a system, and if Eskom's IL contracts come to an end,<br />

Eskom would surely seek new IL contracts.<br />

2. LRMC<br />

Table 12 in Appendix 12 shows that the LRMC does not vary significantly with the reserve margin (i.e. with the<br />

alternative plan) beyond 2015.<br />

With the methodology presented in Section 7, the LRMC should depend on<br />

the amount of plant to be built to meet a 500 MW load increase, which depends on the reserve margin criterion.<br />

3. Wind generator<br />

Section 9, in Appendix 3, should indicate the fuel/wind availability: when is it available during the day and with<br />

what probability?<br />

What capacity credit do you give the wind generator for reserve margin calculations?<br />

68<br />

4. Imported hydro<br />

& The capital cost of imported hydro differs in Table 6 of the main report ( Rm 17044) and in Table 3 of Appendix<br />

1 (Rm 19366).<br />

& The life of the imported hydro plant is given as 30 years, much lower that the life of a pumped storage plant or<br />

a <strong>PBMR</strong> (40 years). This is not realistic. A dam can last 100 years, and a hydro generating unit 40 or 50 years.<br />

NIRP2 Reference Case Handling of Risks<br />

I noticed in your executive summary (Section 6) and in the main report (section 2.3) the way you handle risk:<br />

"The reference plan uses a constraint of 10% on the reserve margin. In addition the un-served energy is<br />

constrained to a maximum of 0.11% of total energy demand in any specific year.<br />

In order to address some risks to some extent and to determine reserve margin exposure to lead time, four<br />

alternative plans to the NIRP Reference plan were developed for increasing levels of constraint on the reserve<br />

margin<br />

As explained previously this Report does not address risk rigorously in this round but rather addresses it<br />

through imposing a minimum reserve margin on the plan of 10%."<br />

& Where did you get the 10% on the reserve margin criterion from and the 0.11 % UE criterion from?<br />

& Why do you need these criteria for planning? Theoretically, your optimization method should yield a plan,<br />

from which you could derive the planned reserve margin and UE.


ARC and Public Comments on NIRP2 Reference Case<br />

& Why do you need to have plans for various reserve margins, from 10 % to 17 %. This is not a random choice.<br />

Which on is the best and why?<br />

& The above points should be explained in the report.<br />

& SAPP uses a reserve margin criterion because this was the only way acceptable to all members to agree on<br />

what capacity each member should provide. However the reserve margin criterion itself was selected with a<br />

specific auditable process (see my previous message and attached paper) and was not arbitrary (though<br />

debatable).<br />

I just have a few additional theoretical comments. You could find the same comments and additional /better<br />

ones in the numerous articles available in the literature on this topic.<br />

& In a generation planning problem, the planner has to handle risk (associated with uncertainties), i.e. he has<br />

to have a base/reference plan (e.g. over 10 years) and to define risk handling strategies to deviate from the<br />

plan if uncertainties are realized in a way or another (e.g. if the load forecast increases or decreases, if<br />

nuclear energy is phased out or encouraged, or if gas becomes very cheap or expensive, or if wind energy<br />

becomes a must have option).<br />

& Long ago (20 or 30 or 50 years ago), the planners identified their planning risks, determined a reserve margin<br />

criterion (e.g peak load + 20 %), planned accordingly, and would revise their plans regularly as uncertainties<br />

become realized, and new ones develop.<br />

The problem is that a reserve margin criterion becomes invalid if the load shape changes, or the<br />

reliability changes, or uncertainties change.<br />

& Later (25-35 years ago) the planners moved to a reliability criterion (e.g. 1 days in 10 years loss of load, or<br />

LOLE = 20 hours per year, or UE = .1 % or any similar one).<br />

69<br />

& This is better than a reserve margin criterion, but how do you select the reliability criterion?<br />

& Later (20-30 years ago) the planners moved to a minimum cost to society approach (using the cost of unserved<br />

energy)<br />

& Eskom generation planners moved from a reserve margin criterion (long ago, before my time) to a reliability<br />

criterion (10 % LOLP at the peak of the year) around 1979, but the reliability criterion was derived from the<br />

minimum cost to society approach (using a 0.5 R/kWh cost of un-served energy).<br />

& Later around 1995 Eskom generation planners moved to a pure minimum cost to society approach, mainly<br />

because of the availability of more modern computing tools.<br />

& I am not involved in Eskom ISEP, and I have not seen the plans ISEP9 and/or 9A. I understand that the<br />

Eskom ISEP planners are now also using a reserve margin criterion in addition to the minimum cost to<br />

society approach.<br />

& I saw various Eskom documents where various people compared the reserve margin in Eskom with the<br />

reserve margin in other utilities. This is not very meaningful, unless you know well what risks each utility is<br />

exposed to (i.e. their associated uncertainties), and which risks are mitigated by a reserve margin (i.e.<br />

building reserve plant) and which risks are mitigated by additional strategies (e.g. plant mix, flexibility, etc),<br />

strategies which might be cheaper than building additional reserve plant.<br />

& The problem with handling risk in planning, is that it changes from year to year in future (uncertainties<br />

increase as you look further in the future), therefore the reserve margin criterion should change every year in


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix A<br />

your planning process (e.g. 8 % in 2004, 9 % in 2005, 10 % in 2006, etc...) but there is a limit in future, where it<br />

is not meaningful to plan to build additional reserve, since there would be time to change the plans (e.g. in<br />

SAPP, the reserve margin criterion is optimized to mitigate risk over 4 years, e.g. if one notices a load<br />

forecast increase in year 1, the utility can do something about it in year 4, e.g. install a GT or contract for<br />

interruptible load).<br />

III. EIUG COMMENT ON NIRP 2003/4 REFERENCE CASE VERSION 18 DECEMBER 2003<br />

Provided by Mr Arnot Hepburn, EIUG Sectretariat<br />

Impressions<br />

1. The Eskom / ERI-UCT / NER team are to be congratulated on developing the NIRP document from what<br />

was previously a high level comparison of planning scenario options to a study report making specific<br />

project recommendations.<br />

70<br />

2. EIUG Members welcome the publication of a significantly more comprehensive NIRP than previously<br />

issued which provides information that is essential to the business planning of energy intensive users.<br />

3. Although the NER was under the impression that they had given 4 weeks for comment the fact that the<br />

document was released just before the Christmas recess meant that most recipients were afforded less<br />

than 2 weeks to review and comment on this critical document. This has negatively impacted on the<br />

review and comments received.<br />

General Comments<br />

4. It is important to note that the optimum choice of technology is very dependent on the selected discount<br />

rate, with higher discount rates favouring less capital-intensive plant with shorter lead times. This mirrors<br />

the international trend towards more flexible technology options and away from traditional coal-fired and<br />

hydro stations.<br />

5. Due to the high regulatory uncertainty, independent power producers may well require rates of return<br />

higher than 10%, thereby affecting the appropriate technology choice. This effect should be taken<br />

into consideration.<br />

6. It is noted that although a range of demand projections are presented, the alternatives are only considered<br />

against a single demand forecast. There needs to be consideration of the course of action under the<br />

high demand scenario at least, or at the very least a qualitative description of the response to that<br />

scenario.<br />

7. A load duration curve and a forecast for its evolution over time should be included, so as to provide the<br />

minimum required information for attracting independent power producers into the ESI in the medium to<br />

long term.<br />

8. The full impact of the appropriate reserve margin should be considered - 10% appears low by


ARC and Public Comments on NIRP2 Reference Case<br />

1<br />

international norms, which are around 20% for long-term planning purposes . While the<br />

appropriate reserve margin differs from market to market, and should be a result of a thorough<br />

LOLP and VOLL analysis, the specific characteristics of the South African system, i.e. a high<br />

degree of uncertainty on demand forecasts and the inflexible and long lead-time technologies<br />

used in SA (coal PF, pump storage) would indicate the need for a higher rather than lower reserve<br />

margin.<br />

9. The EIUG have stated at IRP ARC meetings and would again like to place on record that we do not<br />

agree with interruptible load being considered as 'firm capacity' as this capacity can only be used in<br />

an emergency and is only 'firm' for a contractually limited time period each week.<br />

10. We are surprised to find that media sources, such as the Engineering News, serve as references for cost<br />

estimations (Appendix 3 footnote 64, p25). This creates doubt over the reliability of this information and<br />

should be avoided in future.<br />

11. The report has been enhanced by the addition of the appendices however there is very limited reference to<br />

specific sections in the appendices within the text of the report negating the effective transfer of<br />

information to the reader. This should be addressed in editing the report.<br />

12. The opening paragraph of the report mentions taking into account committed contracts for imports and<br />

exports to South Africa from neighbouring states which is tie-line trading. The NEPAD initiative would<br />

require South Africa to be the anchor customer for bulk import of new hydropower as envisaged from the<br />

so-called Western Corridor (DRCANSA Interconnection). Lack of comment on the impact of such<br />

regional initiates on the NIRP appears to be an omission.<br />

Specific Comments<br />

71<br />

13. In Table 6 of the main report (p18) entitled 'Summary Table of New Supply Side Options Data', the<br />

efficiency ascribed to the CCGT's appears low. A figure of 50% is routinely quoted in international papers.<br />

14. In Table 8 of Appendix 1, no fuel costs have been allocated to the pumped storage units i.e. off-peak<br />

electricity purchases for pumping. It is important to know whether, in the evaluation of the viability of<br />

pumped storage units, the cost of the additional coal that has to be burnt for the pumping cycle was<br />

included as a variable pumped storage cost. Table 8 implies that this has not been done and if so, should<br />

be rectified.<br />

15. Table 2 of Appendix 2 (p3) shows that 2,400 MW of new build SCGT is to be fired on local syngas. The<br />

assumption that as much as 2,400 MW of local syngas will actually be available seems quite optimistic.<br />

The other SCGT fuel source is Kerosene as it is currently cheaper than diesel, although kerosene is a<br />

government subsidised fuel and it is not certain if it would be appropriate to subsidise a peak power<br />

station's fuel source.<br />

16. In paragraph 5 of Appendix 3 the Fluidised Bed Coal Fired <strong>Plan</strong>t is discussed. The lower firing<br />

temperatures in a fluidised bed boiler certainly limits the formations of NOX's. However the SOX's are<br />

dependent on the coal characteristics and presumably limestone will be required. It appears as if<br />

limestone costs are not included in the variable costs of this technology. In addition, the coal<br />

costs appear to be low and should be confirmed with the owners of the reserves.<br />

17. The efficiency range quoted (in note 51) of 35.2 to 42.1 presumably refers to pressurised and other<br />

advanced fluidised bed technologies. We assume that the technology in the NIRP is basic fluidised<br />

combustion. For this technology an efficiency of 37.36% seems to be very optimistic.<br />

1 <strong>National</strong> Grid Company of the UK “Seven Year Statement” www.nationalgrid.com


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix A<br />

18. Points 4 to 7 in the Conclusions of the Executive Summary and the Report are welcomed as they are clear<br />

recommendations to implement specific projects but these should all have the required commissioning<br />

date (or first to last unit commissioning dates) as has been done with point 5 to stress the need.<br />

19. The Conclusions need to make a clear statement regarding why the import of bulk hydropower is<br />

not considered in the report.<br />

20. The Conclusions need to make a clear statement as to whether the studies identified any<br />

inadequacies or constraints in the transmission system that could impact on the quality of supply.<br />

21. Question - are the amounts of dispatched imbedded generation (municipal and industrial)<br />

included in the load forecast (fig 1 page 5) to give the total consumption since imbedded<br />

generation is included in the supply side availability figures.<br />

22. Executive summary text editing:<br />

Page I para 1 line 4 : ensuring not insuring<br />

Page IV section 5 line 2 : as dictated by the ARC of the NER<br />

Page VII fig 5 title : NIRP reference plan and alternatives at<br />

Page VII conclusion 1 last sentence : (including losses) it is not sufficient.<br />

Report text editing :<br />

Page 14 last line : time-of use tariff is available.<br />

72<br />

IV<br />

IV. ESKOM GENERATION COMMENTS ON NIRP 2003/4 REFERENCE CASE VERSION 18 DECEMBER<br />

2003<br />

Provided by Mr. Gerhard Loedolff<br />

1) Is this a report by Eskom, ERI and NER, or is it a report by Eskom & ERI for NER, or is it a report by NER,<br />

drafted by Eskom and ERI. Depending on the answer, the text needs to be reflective of the position the<br />

report is written from.<br />

2) In the Introduction, it is referred in par 1 that the study is conducted to provide information on the<br />

economics of new electrical generation. Is this really so, or is objective more fold, and directed at<br />

identifying the appropriate level of new capacity additions to meet future supply; assess the<br />

appropriateness of various solutions and reflect on the economic outcome of such solutions?<br />

3) Also in the Introduction, a number of bullets is listed as steps defined and carried forward from NIRP1.<br />

However, on many of them the objective (to achieve what?) is not specified. Therefore, as an example,<br />

you are 'Selecting a preferred <strong>Plan</strong>' to achieve what?; or you are analyzing financial consequences of<br />

What?<br />

4) At the top of page 2, the report refers to the "NER agreeing to...." . Surely the NER appointed ARC to<br />

develop the planning assumptions.<br />

5) Especially on DSM, the report contains a huge amount of debate and policy and management suggestions<br />

to NER. To my knowledge this is outside of the scope of this report. I would have expected a good review of<br />

assumptions, with possible implications of deviation on the study outcomes. Refer pages 14- 16


ARC and Public Comments on NIRP2 Reference Case<br />

6) Paragraph 3.3: 2% to 3% represents a movement of 50%. can you not<br />

7) close the gap somewhat?<br />

8) Par 3.5: Surely such a statement needs some explanation?<br />

9) Par 3.7: No indication is provided on the relevance of this information<br />

10) Par 3.7.2: No indication as to why sales growth is assumed to be higher in earlier than later years. Also<br />

impact of TOU based WEPS rates not referred to.<br />

11) Who is DOE?<br />

12) Wording around Eskom's plant performance is again confusing. Suggest it reflects that it is based on<br />

90:7:3, with an average long term EAF of 88%, as also discussed at the last ARC meeting, and as used.<br />

(p27)<br />

13) In a number of places in the report, restructuring of the text to bullet format will substantially ease reading.<br />

14) Par 5.4: New Supply Side Options were recognized, BUT not included. Why?<br />

15) R60/ton for coal to the 6-pack appears underestimated by around R20/ton, while overnight capital appears<br />

about R100/kW higher that latest used in ISEP<br />

16) Suggest that the screening curves should focus only on proven technologies, and not on the speculative /<br />

developing ones in the main report. Can include an annex to give relative position to adopted supply side<br />

options<br />

73<br />

17) Section 6 deals with some issues around reliability of supply. Rather than opening a debate here, which<br />

could also be based on invalid assumptions like Cost of non supply, should the current regulatory standard<br />

w.r.t. QoS criteria as applied via licenses not rather serve as the basis?<br />

18) The plan on p29 indicates OCGT's being decided upon ahead of Komati and Grootvlei. From the<br />

discussion at the ARC meeting this appears to be the result of artificially constraining the return of<br />

Grootvlei and Komati. Is this still so; If so, Please correct!


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix A<br />

V<br />

V. COMMENTS FROM DARLING IPP<br />

Provided by Mr. Herman Oelsner<br />

I would like to put on record our disappointment that input given in our E-mail dated 2nd of December (copied<br />

below) has not found its way into the modelling.<br />

The committee could find itself soon in a very embarrassing situation since Renewable Energy Sources and<br />

Technologies have largely been ignored. This despite clear government (RE White Paper) policy and targets<br />

and numerous country-wide spread activities in this sector.<br />

From the Renewable Sector's view it appears to be "business as usual".<br />

In order to enable a more valuable contribution from the Renewable Energy Service sector, I would like to<br />

propose the co-option of two new additional members from RES to the committee which can assist me in<br />

effectively contributing to the process.<br />

Since there was only short time to look at the documentation you distributed, I had no opportunity to query<br />

certain figures in the modelling results.<br />

For example:<br />

74<br />

The lead times for wind are much shorter and should be recorded as:<br />

a Concept Phase<br />

one year<br />

b Feasibility phase<br />

two years (Darling as first-off is a bad example/ see<br />

Klipheuwel EIA took less a year)<br />

c Investment and construction one year maximum for 20 MW<br />

Extremely short lead times and the possibility of small decentralized plants which can integrate into existing<br />

national grid are the outstanding advantages of wind electricity generation.<br />

a.Life (yrs) 25 (not 20)<br />

b.Maximum Capacity factor 35% (not 19.27)<br />

c.Minimum Capacity factor 20 %(not 4,85)<br />

d.Operational Mode is not in base load but generation takes place dominantly during peak and standard times.<br />

e.Energy Limit per station of 20 MW is 54 GWh/a not 33.5<br />

There are several abbreviations in the documentation, which I do not recognize. A key would be of great help.<br />

Renewable Energy generation, solar / wind does not appear at all in the NIRP <strong>Plan</strong>s for Publication projecting<br />

plans until 2022.<br />

At last weeks World Wind Energy Conference Honourable Minister Ms Phumzile Mlambo-Ngcuka announced<br />

that the government will ratify in Cabinet on Wednesday the 3rd of December the Renewable Energy White<br />

Paper.<br />

The White Paper sets a 10-years target of 10 000 GWh renewable energy contribution to final energy<br />

consumption by 2013, from wind, biomass, solar and small hydro. Since wind is arguably at present the most<br />

economic mode of electricity generation and a well developed technology, wind will play a dominant role in new<br />

generation plant in South Africa in the near future. Assuming that wind will contribute at least half for this target,


ARC and Public Comments on NIRP2 Reference Case<br />

would translate into 10 off 20 MW wind farms, which is very realistic and rather conservative.<br />

The implementation progress will be evaluated mid-term in order to find out whether it will be necessary to<br />

revise the White paper.<br />

Based on the White Paper, the first draft renewable energy strategy is expected to be published in February<br />

2004.<br />

I respectfully submit that RE must be included in the NIRP Reference <strong>Plan</strong>.<br />

VI<br />

75<br />

VI. COMMENTS FROM KELVIN IPP<br />

Provided by Mr. Donald Bennett<br />

I have been through the document and do not have any major comments about it in general. The only point<br />

that I would like to make is that the reference to Kelvin Power Station is incorrect (Appendix 1 page 3 table 2).<br />

Kelvin (A & B) is grouped with the “Munics 1 & 2”. Kelvin was in fact privatized in November 2001 and operates<br />

as an IPP (although only serving the City of Johannesburg under a Long Term Agreement at this point in time).<br />

Reference is also made in point 5.2 (Non-Eskom System Existing Capacity) page 15 of the main document to<br />

the fact that Kelvin generation is included in the “Munic 1 & 2” blocks.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix D<br />

Appendix D<br />

NIRP ARC COMMENTS ON THE NIRP2 STAGE 2 REPORT<br />

I. ESKOM KSACS COMMENT 77<br />

Concept of expectation / Definition of the word “expected” 77<br />

Uncertainties considered (Section 4) 77<br />

Range of values for uncertain parameters (Section 4) 77<br />

Definition of scenarios (futures) (Section 4) 78<br />

Simulation of plans , and cost estimates (Sections 4 and 5) 79<br />

Renewable technologies (Section 7.3) 80<br />

Conclusion 80<br />

II. EIUG COMMENT ON NIRP2 STAGE 2 REPORT 80<br />

III. DEPARTMENT OF MINERALS AND ENERGY COMMENTS<br />

ON RENEWABLE ENERGY SCENARIO 81<br />

76


NIRP ARC Comments on NIRP2 Stage 2 Report<br />

I<br />

I. ESKOM KSACS COMMENT 22 August, 2004<br />

COMMENTS ON NIRP 2003/4 STAGE 2 REPORT<br />

Personal comments by JL Pabot<br />

The principle of the methodology used in the report to develop an optimal plan seems reasonable, but I have<br />

serious doubts on the implementation techniques applied with this methodology to derive the recommended<br />

plan, which in my opinion invalidates the results.<br />

Therefore I cannot determine from the report if the recommended plan is truly the best plan.<br />

Concept of expectation / Definition of the word “expected”<br />

The word “expected” is mentioned at many places in the document, but It does not seem to have the usual<br />

meaning, which is confusing for the reader.<br />

For me, when a parameter (e.g. availability of plant) has a statistical distribution of values over a range (low,<br />

median, high), the expected value is the probability weighted average over the range, usually close to the<br />

median value.<br />

In the whole report, the expected value of a parameter seems to always be at one end of the range, always the<br />

least favourable (i.e. the best) end for capacity investment (the side requiring the least capacity installed). All<br />

other values are worse, i.e. lead to higher capacity investment.<br />

77<br />

Uncertainties considered (Section 4)<br />

The report addresses only uncertainties that have a direct impact on the load/capacity balance.<br />

Other uncertainties that might have a significant impact on the plan, are not considered, e.g. fuel cost or fuel<br />

availability (except for imported hydro).<br />

Range of values for uncertain parameters (section 4)<br />

As mentioned in comment 1 above, the range of values selected for the analysis for the uncertain parameters<br />

is systematically biased towards the worst end of the range (i.e. the values requiring the highest capacity<br />

installed). The expected value being the lowest value considered.<br />

This obviously will lead to an optimal plan requiring more capacity than truly required.<br />

Examples of parameters that could have more favourable values than expected, i.e. outside the range<br />

considered in the study:<br />

& Load growth forecast: Surely there is some probability that there might be an economic crisis due to some<br />

international event (high petrol price, financial crisis, war in the middle, crisis in a neighbouring country,<br />

impact of AIDS, etc) which might lead to lower energy consumption growth. Export sales to SAPP might also<br />

decrease if new stations are built in SAPP.


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix D<br />

& Imported energy: Surely there is some probability that Eskom could import more power from SAPP, e.g. from<br />

Inga 1-2 after refurbishment, from ZESCO in Zambia, when they have finished refurbishing their plant, from<br />

Kafue Gorge lower, from Kudu in Namibia, if the plant is built primarily for supplying Nampower, and if Eskom<br />

buys the balance of energy generated, etc…<br />

& Interruptible load (IL) and DSM: it is quite likely that in future Eskom may contract for more IL capacity,<br />

possibly with less usage constraints, and for more demand management programmes (DMP) or DSM<br />

programmes.<br />

The probabilities allocated to the parameters values on the worst (for MW to be built) end of the range seem<br />

excessive, e.g. 70 % for available capacity<br />

Definition of scenarios (futures) (Section 4)<br />

There is an implicit (not discussed in the text) assumption in the scenarios: the 4 uncertain parameters are of a<br />

random nature, and are independent.<br />

At least one parameter, the existing IL MW capacity, is not a random parameter. The IL contracts are to a large<br />

extent under Eskom's control, i.e. their continued existence cannot be used in a probabilistic analysis.<br />

The 4 parameters are not independent in the long term, and a few of them are also not independent in the short<br />

term.<br />

78<br />

& IL MW capacity is not independent of the other parameters. Eskom is unlikely to cancel (or renegotiate)<br />

these contracts if there is a shortage of capacity to replace them (e.g. if there is some indication of a high load<br />

growth, or if imports are curtailed).<br />

& The same can be said of the municipal generation (it will not be retired if its capacity is needed) and of the<br />

plant availability (if low, Eskom will strive to improve it if there is a shortage of capacity, at least within a year or<br />

two).<br />

& The MW capacity of DSM programmes contracted by Eskom is not independent of the other parameters:<br />

Escom will invest more resources in developing these programmes if there is more need for them (e.g. for<br />

high load growth)<br />

& The MW capacity of imports is also not independent of the other parameters: Eskom will not give up part of its<br />

contractual MW allocation form Cahora Bassa at Songo if this capacity is needed in South Africa. Also<br />

Eskom will import more energy form SAPP if there is a need for it, mainly because Eskom can then offer a<br />

higher price.<br />

& The load forecast includes the energy exported to SAPP (about 2100 MW peak power in 2004). Most of<br />

Eskom's export contracts are expiring soon, part of the existing contract are non-firm (Eskom can decline to<br />

sell energy at 1 day notice). In future Eskom will reduce exports if there is a prospect of capacity shortage.<br />

Therefore the definition of the scenarios (by combining all the values of the uncertain parameters), and the<br />

derivation of their probabilities (by multiplication of the individual probabilities), is not appropriate for this<br />

expansion planning exercise.<br />

It would be more appropriate to define a set of 3 values for the uncertain parameters (low, medium, high),<br />

assess their interdependence, and derive by judgement a set of 4 or 5 realistic futures.<br />

With reference to my comment 1, it is very odd that the future (scenario 1) with all parameters having their<br />

expected values has a probability of 3 % and that all the other futures (with a combined probability of 97 %) are


NIRP ARC Comments on NIRP2 Stage 2 Report<br />

all worse (in terms of capacity requirements), even much worse for many of them.<br />

This reflects a bias in the study towards the worst cases, requiring higher installed capacity.<br />

Simulation of plans , and cost estimates (sections 4 and 5)<br />

The NIERP planners (the authors of the study) design 16 plans for the 16 futures. They then simulate each plan<br />

for each future, over the study period (8 to 20 years) assuming that the plans remain as designed for the whole<br />

duration of the study period.<br />

This does not make sense: a plan designed for a low load growth forecast would not remain unchanged if a<br />

higher load forecast would occur. Eskom would surely take some action within a year or two, e.g. order OCGTs<br />

(lead time = 1 or 2 years), contract more IL, etc…The simulation should make some provision for the<br />

adaptability of the plans to the future under which they are simulated.<br />

The consequence of this methodology implementation technique is to derive very high costs for the plans<br />

designed for favourable (i.e. good, as defined in Comment 1) futures when run under unfavourable (bad)<br />

futures.<br />

Example: The table below shows the PV cost of plans 1 (designed for future 1, the best) and 2 (designed for<br />

future 2, the worst) when run under futures 1 and 2. It shows also the expected cost (probability weighted cost,<br />

PWC) of the plans over the 16 scenarios. These costs were provided by the NIERP planners in a spreadsheet.<br />

Simulation Scenario Scenario PWC<br />

20 years future 1 future 2 cost<br />

79<br />

<strong>Plan</strong> 1, cost Rm 182427 746958 403520<br />

<strong>Plan</strong> 2, cost Rm 215676 240722 222918<br />

The high cost of plan 1 (low capacity installed) for future 2 is due to the high amount of unserved energy<br />

calculated for that case, and to the high cost of unserved energy (20 R/kWh).<br />

& The cost of unserved energy is unrealistic for that case. This is an outage cost, not a shortage cost. As<br />

mentioned extensively in the literature, outage costs are incurred by consumers when unexpected outages<br />

occur, and shortage costs are incurred when outages are expected (e.g. when there is a shortage of capacity<br />

over long periods, e.g. 6 months). Shortage costs are much lower that the outage costs. Obviously in the<br />

case of plan 1 run under future 2, outages would be expected, and a shortage cost should have been used<br />

for unserved energy, not an outage cost.<br />

& The high amount of unserved energy of plan 1 for future 2 is totally unrealistic. <strong>Plan</strong> 1 would not remained<br />

unchanged over 20 years for future 2, nor for any future worst than future 1 (i.e. for all other futures) over 20<br />

years, nor over 8 years, nor over 4 years.<br />

The impact of this invalid methodology implementation technique is to weigh all plans designed for the most<br />

favourable futures with very high unserved energy costs, which leads to very high probability weighted costs<br />

for these plans, and to their elimination on the basis of high PWC.<br />

In effect the study is seriously biased towards plans designed for bad futres, i.e. with high capacity installed.<br />

The study would be more valid if the plans were simulated as adaptable, i.e. if additional gas turbines could be<br />

installed at short notice when needed, or if plant commissioning could be delayed at short notice (with


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix D<br />

additional costs) to cope with changing futures.<br />

Renewable technologies (Section 7.3)<br />

<strong>Plan</strong> 14 with 320 MW of renewable capacity installed over the nest 20 years only pays lip service to the<br />

government's desire to introduce renewable energy in the generation of electricity. I did not check the white<br />

paper on energy policy, so maybe the study is realistic in this respect.<br />

A more visionary scenario would consider a more commendable goal, e.g. 5 % or 10 % of all new installed<br />

capacity to be based on renewable energy.<br />

If in future South Africa moves to gas fired plants with expensive gas fuel (e.g. LNG) for electricity generation,<br />

wind power plants may become economical because of their associated fuel savings, even if they receive no<br />

capacity credit to meet the peak load:<br />

Conclusion<br />

The principle of the methodology used in the report to develop an optimal plan seems reasonable, but the<br />

planning techniques used in this study for the implementation of this methodology, are in my opinion invalid.<br />

In my opinion, the shortcomings identified in the above comments invalidate the results, i.e. I cannot determine<br />

from the report if the recommended plan 14 is truly the best.<br />

I also cannot determine if the recommendation to build 720 MW of Open cycle gas turbines in 2006 is<br />

reasonable.<br />

80<br />

However since the DME representatives stated at a recent meting at the NER that Eskom and the DME had<br />

already agreed that these 720 MW of OCGT would be built in 2006, this capacity is in effect committed, and my<br />

opinion on this point is irrelevant.<br />

II<br />

II.EIUG COMMENT ON NIRP2 STAGE 2 REPORT<br />

Provided by Mr Arnot Hepburn, EIUG Sectretariat<br />

EIUG members in their review of the NIRP2 Stage 2 report are in agreement that the comments submitted<br />

previously and the EIUG concerns raised again at the last NIRP ARC meeting are all that need be given for the<br />

current report. As stated by the EIUG at the last NIRP ARC meeting it is imperative that the release of the report<br />

should not be delayed in any way as the information is urgently needed by decision makers. It is appreciated<br />

that it will never be possible to achieve 100% projections but what is known must be published.<br />

The EIUG gives it's assurance that it will give what ever support possible to future NIRP studies and reports<br />

and submit to you the following comments for consideration in the preparation of NIRP3:<br />

Demand- and consumption growth forecasting<br />

1. There appears to be uncertainty and a lack of agreement on the actual figures in the baselines as used,<br />

and on the expected demand growth in future. For example, in table 1 in the NIRP HIGH column, the sales


NIRP ARC Comments on NIRP2 Stage 2 Report<br />

in 2003 is shown as 197 401 GWh. From the Eskom annual report the actual Eskom sales was 196 980<br />

GWh. The Eskom figures excludes the energy sent out from non-Eskom generation, and therefore it<br />

appears that we are projecting future demand and consumption figures from a too low base. This may<br />

have a significant effect on the actual reserve situation in future.<br />

Further to the above, the 0,5% increase (on top of the NIRP 2 base case) in the demand growth from the<br />

ERC study to arrive at the high growth scenario, seems modest compared to the actual year on year<br />

growth of 5% over the last few years, even if we know of large new industrial loads that came on line<br />

recently. It the actual rate of growth does not taper off to 3% during the remaining months of 2004, we<br />

should consider another upward adjustment to the forecast next year.<br />

2. In table 4, the probabilities assigned to the different primary assumptions seem debatable. A probability of<br />

0.4 is assigned to the high load forecast, while recent history and the current economic outlook seem to<br />

support a higher probability. Similarly, the 0.6 probability that plant outages will be higher implies that<br />

Eskom will not be able to maintain their equipment availability, against a history that they never dropped<br />

below 88%, even in a bad year like 2003. Given the fact that the impact of higher load growth is more<br />

severe than the rest (figure 1), these assumptions greatly influence the results in the 16 scenarios. If a 0.6<br />

probability is assigned to the high load growth assumption it will result in lower reserve margins and higher<br />

PWC in scenarios 2, 6, 8 and 16. If such a relative modest change in a primary assumption can lead to a<br />

scenario of zero reserve margin, the report should point that out, assign a probability to it and sensitize<br />

government to such a possible eventuality.<br />

3. The report is silent on brown fields CF base load options, while it is common knowledge that these<br />

possibilities have shorter lead times and are cheaper than green fields options.<br />

4. The inclusion of 300 MW CSP, at R10bn capital does not seem to be well researched. It is unclear why<br />

wind power cannot contribute more to the 10 000 GWh target of Government.<br />

81<br />

III<br />

III. DEPARTMENT OF MINERALS AND ENERGY COMMENTS ON RENEWABLE ENERGY SCENARIO<br />

Provided by Mr. Andre Otto<br />

The levelised cost for wind is for all discount rates as indicated in table 9 lower than that for CSP wind, what was<br />

then the decision rationale and calculation used to "choose" the significant 300 MW CSP vs only 20 MW wind?<br />

The GEF South African Wind Energy Programme (GEF council approval of full size project in progress) aimed<br />

at an installed wind farm capacity of up to 50 MW (5 MW Darling + 45 MW through SAWEP) by December<br />

2009. 50 MW is regarded as the minimum installed wind farm capacity to attract investment and to start up a<br />

local manufacturing and exporting capability which should lower further wind farm investment in SA.<br />

The Eskom CSP demo plant (as far as I know) is based on 100 MW which still have to secure the necessary<br />

financing and authorisation.<br />

A macro-economic analysis (see attached) done (in cooperation with <strong>National</strong> Treasury) in motivating for


<strong>National</strong> Integrated <strong>Resource</strong> <strong>Plan</strong> 2 - Appendix D<br />

Cabinet approval of the White Paper on Renewable Energy (RE WP) and forming the basis of the RE Strategy<br />

(in progress), indicates a least cost based approached to be followed in implementing the RE WP target of 10<br />

000 GWh RE contribution to energy consumption by 2013.<br />

The Renewable Energy Market Transformation project (REMT) which is approved and financed by the SA<br />

Government, GEF and PCF via the World Bank, investment will start in 2005, aimed at establishing RE<br />

capacity to produce the 1st 1000 GWh of the 10 000 GWh target by 2008. Pending the success, the project will<br />

be expanded to an additional 3000 GWh to be introduced the following 4 years. The REMT is based on the<br />

macro-economic least cost approached of introducing the RE WP. The following RE technologies and<br />

applications (see table below) have been identified through a DME and World Bank economic and financial<br />

due diligence of the REMT.<br />

Recommendation<br />

The NER NIRP be updated with the RE technologies and applications as identified through the DME and<br />

World Bank economic and financial due diligence of the REMT, including CSP and wind energy as indicated in<br />

the attached table.<br />

Please take note: The REMT envisaged to introduce 744 MW RE capacity over the 1st 8 years of the RE target<br />

period which is already in excess of 320 MW.<br />

Footnote in RE WP published in Government Gazette vol 466, 14 May 2004, No 26169:<br />

82<br />

"It is estimated that if the cumulative renewable energy capacity by end of 2013 is<br />

approximately 1667 MW, then 10 000 GWh renewable energy would have been consumed over<br />

the 10 year period"<br />

Dec 03 Jan 07<br />

to Jan to Dec<br />

07 GWh 11<br />

GWh<br />

REMT Phase 1 Phase 2<br />

Sugar sugar mills spare<br />

capacity<br />

reduced process<br />

MW<br />

Annual<br />

load<br />

factor<br />

%<br />

55 55 12 52<br />

109 109 24 52<br />

steam<br />

full scale cogen 551 157 40<br />

SWH 175 1,000 190 60<br />

Pulp Ngodwana 65 65 8 90<br />

&Paper<br />

Additional projects 20 170 21 90<br />

Hydro Identified projects 210 210 63 38<br />

Additional projects 75 1,000 300 38<br />

LFG Identified projects 240 240 34 80.8<br />

Additional projects 51 600 85 80.8<br />

GEF<br />

SAWEP<br />

Wind 120 50 28<br />

Eskom<br />

CSP 613 100 70<br />

Total 1000 4733 894<br />

Total 5733 GWh (57% of 10 000 GWh target)<br />

Balance 4267 GWh most probably taken up by biofuel


Notes<br />

83

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