Water for people.pdf - WHO Thailand Digital Repository

2 6 4 / C H A L L E N G E S T O L I F E A N D W E L L - B E I N GDeveloping Energy to Meet Development NeedsTable 10.5: continuedSystem Technical advantages/disadvantages Ecological advantages/disadvantagesGeothermal Advantages Advantagesheat pumps• A slim hole of only 100–150 metres is necessary, • This technology can offer up to 40% reductions in carbonwith the heat being extracted from the borehole dioxide emissions against competing technologies.by means of a closed loop heat exchanger. • If all of the electricity is supplied from non-fossil sources, there• This is an electrically-based technology that allows high are no carbon dioxide emissions associated with heating andefficiency, reversible, water source heat pumps to be cooling a building.installed in buildings in most geographical and geologicallocations (worldwide).• Reduced need of fuel import.• Simple reliable technology.DisadvantagesDisadvantages• Technology needs electricity. • Negative effects on groundwater (in case of incorrect installation).• Geothermal heat pumps generate thermal energy andnot electricity.Tidal energy Advantages Advantages• Improved transportation due to the development • Reduced greenhouse gas emissions by utilizingof traffic or rail bridges across estuaries.non-polluting tidal power in place of fossil fuels.• Reduction of fuel imports.DisadvantagesDisadvantages• High construction costs. • The construction of a tidal barrage in an estuary will change thetidal level in the basin. This change is difficult to predict, and canresult in a lowering or raising of the tidal level.• This change will also have an effect on the sedimentation andturbidity of the water within the basin.• Navigation and recreation can be affected.• A raising of the tidal level could result in the flooding of theshoreline.• Effect of a tidal station on the plants and animals that live withinthe estuary.Wave energy Advantages Advantages• Large theoretical potential. • reduced greenhouse gas emissions by utilizing non-polluting tidalpower in place of fossil fuels.Disadvantages• High construction costs in relation to energy generation.ConclusionsThe world is facing a situation in which 2 billion people have noelectricity at all, and 2.5 billion people in developing countries,mainly in rural areas, have little access to commercial energyservices. For many inhabitants of cities, losses of power supplyduring the day are a regular feature of life.National energy plans need to focus more on rural and periurbanelectrification and to be better coordinated with other policiesand women’s development needs. From the perspective of technicalmanagement, river flows need to be managed according to needs ofboth upstream and downstream populations, to maintain andupgrade existing facilities, and to integrate ecological and technicalknowledge into the project management. All of these differentperspectives need to be taken together in order to enable and toensure Integrated Water Resources Management (IWRM) in the areaof hydropower. For many countries, implementing such sustainableenergy development practices will be demanding and costly in termsof both project assessment and mitigation measures; it is thereforeessential that improvement in public/private policies should includeother energy options.