chapter 8 hydro energy · 2020. 9. 30. · chapter 8 hydro energy 8.1 summary key messages •...

AUSTRALIAN ENERGY RESOURCE ASSESSMENT

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Chapter 8Hydro Energy

8.1Summary

K E y m E s s a g E s

• Hydroelectricityisamatureelectricitygenerationtechnologyandanimportantsourceofrenewableenergy.

• Hydroelectricityisasignificantenergysourceinalargenumberofcountries,althoughitscurrentshareintotalprimaryenergyconsumptionisonly2.2percentgloballyand0.8percentinAustralia.

• HydroelectricityiscurrentlyAustralia’smajorsourceofrenewableelectricitybutthereislimitedpotentialforfuturefurtherdevelopment.

• WateravailabilityisakeyconstraintonfuturegrowthinhydroelectricitygenerationinAustralia.

• FuturegrowthinAustralia’shydroelectricitygenerationwillbeunderpinnedbythedevelopmentofsmallscalehydroelectricityfacilitiesandefficiencygainsfromtherefurbishmentoflargescalehydroplants.

• TheshareofhydroinAustralia’stotalelectricitygenerationisprojectedtofalltoaround3.5percentin2029–30.

8.1.1Worldhydroenergyresourcesandmarket• Globaltechnicallyfeasiblehydroenergypotential

isestimatedtobearound16500TWhperyear.

• Worldhydroelectricitygenerationwas3078TWhin2007,andhasgrownatanaverageannualrateof2.3percentsince2000.

• Hydroenergyisthelargestsourceofrenewableenergy,andcurrentlycontributesnearly16percentofworldelectricityproduction.

• IntheOECDregion,hydroelectricitygenerationisprojectedbytheIEAtoincreaseatanaverageannualrateofonly0.7percentbetween2007and2030,mainlyreflectinglimitedundevelopedhydroenergypotential.

• Innon-OECDcountries,hydroelectricitygenerationisprojectedbytheIEAtoincreaseatanaverageannualrateof2.5percentbetween2007and2030,reflectinglarge,undevelopedpotentialhydroenergyresourcesinmanyofthesecountries.

8.1.2Australia’shydroenergyresources• Australia’stechnicallyfeasiblehydroenergy

potentialisestimatedtobearound60TWhperyear.

• Australiaisthedriestinhabitedcontinentonearth,withover80percentofitslandmassreceivinganannualaveragerainfalloflessthan600mmperyearand50percentlessthan300mmperyear.

• Highvariabilityinrainfall,evaporationratesandtemperaturesoccursbetweenyears,resultinginAustraliahavingverylimitedandvariablesurfacewaterresources.

• Australiacurrentlyhas108operatinghydroelectricpowerstationswithtotalinstalledcapacityof7.8GW(figure8.1).

8.1.3KeyfactorsinutilisingAustralia’shydroenergyresources• Potentialforthedevelopmentofnewlargescale

hydroelectricityfacilitiesinAustraliaislimited.However,theupgradeandrefurbishmentofexistinghydroelectricityinfrastructurewillincreaseefficiencyandextendthelifeoffacilities.

• ThereispotentialforsmallscalehydroelectricitydevelopmentsinAustralia,andthisislikelytobeanimportantsourceoffuturegrowthincapacity.

• Wateravailability,competitionforscarcewaterresources,andbroaderenvironmentalfactorsarekeyconstraintsonfuturegrowthinAustralianhydroelectricitygeneration.

8.1.4Australia’shydroelectricitymarket• In2007–08,Australia’shydroelectricityuse

represented0.8percentoftotalprimaryenergyconsumptionand4.5percentoftotalelectricitygeneration.Hydroelectricityusehasdeclinedonaverageby4.2percentperyearbetween1999–00and2007–08,largelyasaresultofanextendedperiodofdrought.


226

Figure 8.1 MajorAustralianoperatinghydroelectricfacilitieswithcapacityofgreaterthan10MWsource: GeoscienceAustralia

• In2007–08,hydroelectricitywasmainlygeneratedintheeasternstates,includingTasmania(57percentoftotalelectricitygeneration),NewSouthWales(21percent),Victoria(13percent)andQueensland(8percent).

%

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1999-00 2001-02 2003-04 2005-06 2007-08 2029-30

Electricity generation(TWh)

AERA 8.2

Share of total electricitygeneration (%)

Figure 8.2 Australia’shydroelectricitygenerationto2029–30source: ABARE2009a,2010

• InABARE’slatestlong-termenergyprojectionsthatincludetheRenewableEnergyTarget,a5percentemissionsreductiontargetandothergovernmentpolicies,hydroelectricitygenerationisprojectedtoincreasefrom12TWhin2007–08to13TWhin2029–30,representinganaverageannualgrowthrateof0.2percent(figure8.2).

• Theshareofhydrointotalelectricitygenerationisprojectedtofallto3.5percentin2029–30.

• Hydroenergyisexpectedtobeovertakenbywindastheleadingrenewablesourceofelectricitygenerationduringtheoutlookperiod.

8.2Backgroundinformationandworldmarket8.2.1DefinitionsHydroelectricityiselectricalenergygeneratedwhenfallingwaterfromreservoirsorflowingwaterfromrivers,streamsorwaterfalls(runofriver)ischannelledthroughwaterturbines.Thepressureoftheflowingwaterontheturbinebladescausestheshafttorotateandtherotatingshaftdrivesanelectricalgeneratorwhichconvertsthemotionoftheshaftintoelectricalenergy.Mostcommonly,waterisdammedandthe


227

CHAPTER 8: HYDRO ENERGY

flowofwateroutofthedamtodrivetheturbinesiscontrolledbytheopeningorclosingofsluices,gatesorpipes.Thisiscommonlycalledpenstock.

Hydropoweristhemostadvancedandmaturerenewableenergytechnologyandprovidessomelevelofelectricitygenerationinmorethan160countriesworldwide.Hydroisarenewableenergysourceandhastheadvantagesoflowgreenhousegasemissions,lowoperatingcosts,andahighramprate(quickresponsetoelectricitydemand).

Hydroelectricityhasbeenusedinsomeformsincethe19thcentury.Themaintechnologicaladvantageofhydroelectricityisitsabilitytobeusedforeitherbaseorpeakloadelectricitygeneration,orboth.Inmanycountries,hydroisusedforpeakloadgeneration,takingadvantageofitsquickstart-upanditsreliability.Hydroelectricityisarelativelysimplebuthighlyefficientprocesscomparedwithothermeansofgeneratingelectricity,asitdoesnotrequirecombustion.

Box 8.1 HyDROElECTRICITyTECHNOlOGIES

Hydroelectricity generationTheenergycreateddependsontheforceorstrengthofthewaterflowandthevolumeofwater.Asaresult,thegreaterthedifferencebetweentheheightofthewatersource(head)andtheheightoftheturbineoroutflow,thegreaterthepotentialenergyofthewater.Hydropowerplantsrangefromverysmall(10MWorless)toverylargeindividualplantswithacapacityofmorethan2000MWandvastintegratedschemesinvolvingmultiplelargehydropowerplants.Hydropowerisasignificantsourceofbaseloadand,increasingly,peakloadelectricityinpartsofAustraliaandoverseas.

Riverspotentiallysuitableforhydropowergenerationrequirebothadequatewatervolumethroughriverflows,whichisusuallydeterminedbymonitoringusingstreamgauges,andasuitablesitefordamconstruction.InAustraliavirtuallyallhydropowerisproducedbystationsatwaterstoragescreatedbydamsinmajorrivervalleys.Manyhavefacilitiestopumpwaterbackintohigherstoragelocationsduringoff-peaktimesforre-useinpeaktimes.Insomecases,thehydroplantcanbebuiltonanexistingdam.Thedevelopmentofahydroresourceinvolvessignificanttimeandcostbecauseofthelargeinfrastructurerequirements.Thereisalsoarequirementforextensiveinvestigationoftheenvironmentalimpactofdammingtheriver.Thisgenerallyinvolvesconsiderationoftheentirecatchmentsystem.

Pumped storage hydroelectricitystoreselectricityintimesoflowdemandforuseintimesofhighdemandbymovingwaterbetweenreservoirs.Itiscurrentlytheonlycommercialmeansofstoringelectricityoncegenerated.Byusingexcesselectricitygeneratedintimesoflowdemandtopumpwaterintohigherstorages,theenergycanbestoredandreleasedbackintothelowerstorageintimesofpeakdemand.Pumped-storagesystemscanvarysignificantlyincapacitybutcommonlyconsistoftworeservoirssituatedtomaximisethedifferenceintheirlevelsandconnectedbyasystemofwaterwayswithapumping-generatingstation.Theturbinesmaybereversibleandusedforbothpumpingandgeneratingelectricity.

Pumpedstoragehydroelectricityisthelargest-

capacityformofgridenergystoragewhereitcanbeusedtocovertransientpeaksindemandandtoprovideback-uptointermittentrenewableenergysourcessuchaswind.Newconceptsinpumped-storageinvolvewindorsolarenergytopumpwatertodamsasheadstorage.

mini hydro schemesaresmall-scale(typicallylessthan10MW)hydroelectricpowerprojectsthattypicallyservesmallcommunitiesoradedicatedindustrialplantbutcanbeconnectedtoanelectricitygrid.SomesmallhydroschemesinNorthAmericaareupto30MW.Thesmallesthydroplantsoflessthan100kWaregenerallytermedmicrohydro.Minihydroschemescanbe‘run-of-river’,withnodamorwaterstorage(seebelow),ordevelopedusingexistingornewdamswhoseprimarypurposeislocalwatersupply,riverandlakewater-levelcontrol,orirrigation.Minihydroschemestypicallyhavelimitedinfrastructurerequiringonlysmallscalecapitalworks,andhencehavelowconstructioncostsandasmallerenvironmentalimpactthanlargerschemes.Smallscalehydrohashadhighrelativecosts($perMW)butisbeingconsideredbothforruralelectrificationinlessdevelopedcountriesandfurtherhydrodevelopmentsinOECDcountries,oftensupportedbyenvironmentalpoliciesandfavourabletariffsforrenewableenergy(Paish2002).MostrecenthydropowerinstallationsinAustralia,especiallyinVictoria,havebeensmall(mini)hydrosystems,commencingwiththeThompsonprojectin1989.

Run-of-river systemsrelyonthenaturalfall(head)andflowoftherivertogenerateelectricitythroughpowerstationsbuiltontheriver.largerun-of-riversystemsaretypicallybuiltonriverswithconsistentandsteadyflow.Theyaresignificantinsomeoverseaslocations,notablyCanadaandtheUnitedStates.Minirun-of-riverhydrosystemscanbebuiltonsmallstreamsorusepipedwaterfromriversandstreamsforlocalpowergeneration.Run-of-riverhydroplantscommonlyhaveasmallerenvironmental‘footprint’thanlargescalestoragereservoirs.ThelowerDerwentandMerseyForthhydrodevelopmentsinTasmania,forexample,eachcomprisingsixpowerstationsupto85MWcapacity,usetributaryinflowsandsmallstoragesinastep-likeseries.


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Processing, Transport,End Use Market

StorageResources Exploration

AERA 8.3

Industry

Commercial

Residential

Domesticmarket

Development andProduction

Developmentdecision

ElectricityGeneration

Project

Resourcedefinition andsite selection

Storage

Figure 8.3 Australia’shydroenergysupplychainsource: ABAREandGeoscienceAustralia

Hydroelectricitygenerationisoftenconsideredamaturetechnologywithlimitedscopeforfurtherdevelopment.Plantscanbebuiltonalargeorsmallscale,eachwithitsowncharacteristics:

• Large scale hydroelectricity plantsgenerallyinvolvethedammingofriverstoformareservoir.Turbinesarethenusedtocapturethepotentialenergyofthewaterasitflowsbetweenreservoirs.Thisisthemosttechnologicallyadvancedformofhydroelectricitygeneration.

• small scale hydroelectricity plants,includingmini(lessthan5MW),micro(lessthan500kW)andpicofacilities,arestillatarelativelyearlystageofdevelopmentinAustralia,andareexpectedtobethemainsourceoffuturegrowthinhydroelectricitygeneration.Whilethereisnouniversallyaccepteddefinitionofsmallscalehydroelectricprojects,smallprojectsaregenerallyconsideredasthosewithlessthan10MWcapacity.

Withinthesetwobroadclassesofhydroelectricfacilities,therearedifferenttypesoftechnologies,includingpumpedstorageandrun-of-river(box8.1).Thetypeofsystemchosenwillbedeterminedbytheintendeduseoftheplant(baseorpeakloadgeneration),aswellasgeographicalandtopographicalfactors.Eachsystemhasdifferentsocialandenvironmentalimpactswhichmustbeconsidered.

Inthisreport,electricitygeneratedfromwaveandtidalmovements(coastalandoffshoresources)istreatedseparatelytothatgeneratedbyharnessingthepotentialenergyofwaterinriversanddams(onshoresources).Waveandtidalenergyisdiscussedinchapter11.

8.2.2HydroelectricitysupplychainFigure8.3isarepresentationofhydroelectricitygenerationinAustralia.InAustraliavirtuallyallhydroelectricityisproducedbystationsatwaterstoragescreatedbydamsinmajorrivervalleys.Anumberhavefacilitiestopumpwaterbackintohigherstoragelocationsduringoff-peaktimesforre-useinpeaktimes.Electricitygeneratedbythewaterturbinesisfedintotheelectricitygridasbaseloadandpeakloadelectricityandtransmittedtoitsendusemarket.

8.2.3WorldhydroelectricitymarketHydroenergyisasignificantsourceoflowcostelectricitygenerationinawiderangeofcountries.Atpresent,productionislargelyconcentratedinChina,NorthAmerica,OECDEuropeandSouthAmerica.However,manyAfricancountriesareplanningtodeveloptheirconsiderablehydroenergypotentialtofacilitateeconomicgrowth.Worldhydroelectricitygenerationisprojectedtogrowatanaverageannualrateofaround2percentto2030,largelyreflectingtheincreaseduseofhydroelectricityindevelopingeconomies.

ResourcesMostcountrieshavesomepotentialtodevelophydroelectricity.Therearethreemeasurescommonlyusedtodefinehydroenergyresources:

• gross theoretical potential–hydroenergypotentialthatisdefinedbyhypothesisortheory,withnopracticalbasis.Thismaybebasedonrainfallorgeographyratherthanactualmeasurementofwaterflows.

• Technically feasible–hydroenergypotentialthatcanbeexploitedwithcurrenttechnologies.Thisissmallerthangrosstheoreticalpotential.


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• Economically feasible–technicallyfeasiblehydroenergypotentialwhichcanbeexploitedwithoutincurringafinancialloss.Thisisthenarrowestdefinitionofpotentialandthereforethesmallest.

Theworld’stotaltechnicallyexploitablehydroenergypotentialisestimatedtobearound16500TWhperyear(WEC2007).Regionswithhighprecipitation(rainfallormeltingsnow)andsignificanttopographicreliefenablinggoodwaterflowsfromhighertoloweraltitudestendtohavehigherpotential,whileregionsthataredrier,thatareflatordonothavestrongwaterflowshavelowerpotential.Asia,AfricaandtheAmericashavethehighestfeasiblepotentialforhydroelectricity(figure8.4).

China’shydroenergyresourcesarethelargestofanycountry.Chinaisestimatedtohaveatheoreticalpotentialofmorethan6000TWhperyear,approximatelydoublecurrentworldhydroelectricitygeneration,andeconomicallyfeasiblepotentialofmorethan1750TWhperyear(HydropowerandDams2009).Chinaisalsohometothelargestsinglehydroelectricityprojectintheworld,ThreeGorges.

Whencompleted,thissitewillhaveacapacityof22500megawatts.Itgeneratedalmost50TWhofelectricityin2006(representingonlyaround31percentcapacityutilisation),morethanthreetimesAustralia’stotalhydroelectricitygeneration.

InAfrica,theDemocraticRepublicoftheCongohasthehighesthydroenergypotential,whileNorway’spotentialresourcesarethehighestinWesternEurope.InSouthAmerica,thehighesthydroenergypotentialisinBrazil,whereitexceeds2200TWhperyear.OthercountrieswithsubstantialpotentialincludeCanada,Chile,Colombia,Ethiopia,India,Mexico,Paraguay,TajikistanandtheUnitedStates.Nevertheless,almostallcountrieshavesomehydroenergypotential.

Australia’stheoreticalhydroenergypotential(265TWhperyear)isconsideredtoberelativelysmall,ranking27thintheworld(figure8.5).Highrainfallvariability,lowaverageannualrainfallovermostofthecontinent,andhightemperaturesandevaporationrateslimittheavailabilityofsurfacewaterresources(WEC2007).

0

Total

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South America

Europe

Africa

Oceania

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TWh/year

North America

AERA 8.4

Gross theoreticalpotential

Technicallyfeasible

Economicallyfeasible

4

Figure 8.4 Worldhydroelectricitypotential,byregionsource: HydropowerandDams2009

0 1000 2000 4000 70003000 5000

TWh/year

China

United States

India

Brazil

Russian Federation

Canada

Indonesia

Peru

Congo

Columbia

Australia AERA 8.5

6000

Figure 8.5 Grosstheoreticalhydroelectricitypotential,majorcountries

source: HydropowerandDams2009

Table 8.1 Keyhydrostatistics

a

unit australia 2007–08

oECD 2008

World 2007

Primary energy consumption PJ 43.4 4654 11084

Shareoftotal % 0.8 2.0 2.2

Averageannualgrowth,from2000 % -4.2 -0.3 2.0

Electricity generation

Electricityoutput TWh 12 1293 3078

Shareoftotal % 4.5 12.2 15.6

Electricitycapacity GW 7.8 366.9 848.5

a Energyproductionandprimaryenergyconsumptionareidenticalsource: IEA2009a;ABARE2009a;HydropowerandDams2009


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Primary energy consumptionHydroelectricitygenerationhasbeengrowingglobally,reflectingitsincreasingpopularityindevelopingeconomiesasarelativelycheap,simpleandreliablesourceofenergy(figure8.6).

Hydroelectricitygenerationaccountedfor2.2percentoftotalprimaryenergyconsumptionin2007(table8.1).Worldhydroelectricityconsumptionhasgrownatanaverageannualrateof2percentbetween2000and2007.However,intheOECD,hydroelectricityconsumptionhasbeendecliningatanaverageannualrateof0.3percent.

ConsumptionofhydroelectricityhasalsodeclinedinAustraliaduetotheprolongedperiodofdrought,particularlyinNewSouthWalesandVictoria,thathasaffectedhydroelectricitygeneration.

Electricity generationHydroelectricityaccountedfor16percentofworldelectricitygenerationin2007.Hydroelectricity’sshareintotalelectricitygenerationhasdeclinedfrom22percentin1971to16percent(figure8.6),becauseofthehigherrelativegrowthofelectricitygenerationfromothersources.latinAmericancountriesaccountforthelargestproportionofhydroelectricitygeneration,followedbyOECDNorthAmerica.ThemostrapidgrowthinhydroelectricitygenerationhasbeeninChina,whichisnowthefourthlargestgenerator.ManyAfricaneconomiesarealso

developingtheirhydroenergypotential,andhave

becomeasourceofgrowth.

Totalinstalledhydroelectricitygenerationcapacityis

currentlyaround849GW,witharound158GWofnew

capacityunderconstructioninlate2008(Hydropower

andDams2009).Some25–30GWofnewlarge

scalehydroenergycapacitywereaddedin2008,

mostlyinChinaandIndia(Ren212009).Chinahas

theworld’slargestinstalledhydroelectricitycapacity

witharound147GW(17percentofworldcapacity),

followedbytheUnitedStates,Brazil,Canadaandthe

RussianFederation.Theseeconomiesaccountfor

halfoftheworld’sinstalledhydroelectricitygeneration

capacity.In2008therewerearound200large

(greaterthan60mhigh)damswithhydroelectricity

facilitiesunderconstruction.

Thetotalinstalledcapacityofsmallhydroenergyisestimatedtobeabout85GWworldwide(Ren212009).MostofthisisinChinawheresome4–6GWperyearhavebeenaddedforthepastseveralyears,butdevelopmentofsmallhydroplantshasalsooccurredinotherAsiancountries.

In2007,worldproductionofhydroelectricitywas3078TWh(around11000PJ).ThelargestproducerswereChina,Brazil,CanadaandtheUnitedStates(figure8.7a).Australiaranked31stintheworld.Hydroelectricityaccountedforalargeshareoftotal

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Share of totalelectricity generation (%)

AERA 8.6

Figure 8.6 Worldhydrogenerationandshareoftotalelectricitygenerationsource: IEA2009a


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6

electricitygenerationinsomeofthesecountriesincluding,mostnotably,Norway(98percent),Brazil(84percent),Venezuela(72percent),Canada(58percent)andSweden(44percent)(figure8.7b).

0 400 00

TWh300 500

a) Electricity output

China

Brazil

Canada

United States

Russian Federation

Norway

India

Venezuela

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Australia

100 200

0

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China

Brazil

Canada

United States

Russian Federation

Norway

India

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Japan

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Australia AERA 8.7

20 40 60 80 100

%Figure 8.7 Worldelectricitygenerationfromhydro,majorcountries,2007

source: IEA2009a

Hydroelectricitymeetsover90percentofdomesticelectricityrequirementsinanumberofothercountriesincluding:theDemocraticRepublicoftheCongo,Ethiopia,lesotho,Malawi,Mozambique,NamibiaandZambiainAfrica;Bhutan,Kyrgyzstan,laos,Nepal

andTajikistaninAsia;AlbaniaandNorwayinEurope;andParaguayinSouthAmerica(HydropowerandDams2009).

outlook for the world hydroelectricity marketIntheIEAreferencecaseprojections,worldhydroelectricitygenerationisprojectedtoincreaseto4680TWhin2030,atanaverageannualrateof1.8percent(table8.2).HydroelectricitygenerationisprojectedtogrowintheOECDatanaverageannualrateof0.7percentandinnon-OECDcountriesbyanaverageannualrateof2.5percent.

ThegrowthinhydroelectricitygenerationintheOECDisexpectedtocomefromutilisationofremainingundevelopedhydroenergyresources.Growthisalsoexpectedtooccurinsmall(includingminiandmicro)andmediumscalehydroelectricityplants.Improvementsintechnologymayalsoimprovethereliabilityandefficiencyand,hence,outputofexistinghydroelectricityplants,aswouldrefurbishmentofageinginfrastructure.

Innon-OECDcountries,growthisexpectedtobeunderpinnedbythecostcompetitivenessofhydroelectricitycomparedwithothermeansofelectricitygeneration.Muchofthegrowthisexpectedtobeinsmallscalehydroelectricity,althoughthereareplansinmanyAfricancountriestobuildlargescalehydroelectricitygenerationcapacity.GrowthisalsoexpectedtooccurinAsia,particularlyChina.

Theimplementationofglobalclimatechangepoliciesislikelytoencouragethedevelopmentofhydroelectricityasarenewable,lowemissionsenergysource.IntheIEA’s450climatechangepolicyscenario,theshareofhydroinworldelectricitygenerationisprojectedtoincreaseto18.9percentin2030,comparedwith13.6percentinitsreferencecase.FortheOECDregions,underthisscenario,theshareofhydrointotalelectricitygenerationisprojectedtoincreaseto13.5percentin2030comparedwith11.2percentinthereferencecase.

Table 8.2 IEAreferencecaseprojectionsforworldhydroelectricitygeneration

unit 2007 2030

oECD TWh 1258 1478

Shareoftotal % 12.2 11.2

Averageannualgrowth,2007–2030 % - 0.7

Non-oECD TWh 1820 3202



World TWh 3078 4680



source: IEA2009b


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8.3Australia’shydroenergyresourcesandmarket

8.3.1HydroenergyresourcesAustraliaisthedriestinhabitedcontinentonearth,withover80percentofitslandmassreceivinganannualaveragerainfalloflessthan600mmperyearand50percentlessthan300mmperyear(figure8.8).Thereisalsohighvariabilityinrainfall,evaporationratesandtemperaturesbetweenyears,resultinginAustraliahavingverylimitedandvariablesurfacewaterresources.OfAustralia’sgrosstheoreticalhydroenergyresourceof265TWhperyear,onlyaround60TWhisconsideredtobetechnicallyfeasible(HydropowerandDams2009).Australia’seconomicallyfeasiblecapacityisestimatedat30TWhperyearofwhichmorethan60percenthasalreadybeenharnessed(HydropowerandDams2009).

ThefirsthydroelectricplantinAustraliawasbuiltinlauncestonin1895.Australiacurrentlyhas108operatinghydroelectricpowerstationswithtotalinstalledcapacityof7806MW.ThesecoincidewiththeareasofhighestrainfallandelevationandaremostlyinNewSouthWales(55percent)

andTasmania(29percent)(figure8.9).TheSnowyMountainsHydro-electricScheme,withacapacityof3800MW,accountsforaroundhalfofAustralia’stotalhydroelectricitygenerationcapacitybutconsiderablylessofactualproduction.Therearealsohydroelectricityschemesinnorth-eastVictoria,Queensland,WesternAustralia,andamini-hydroelectricityprojectinSouthAustralia.Pumpedstorageaccountsforabout1490MW.

TheSnowyMountainsHydro-electricSchemeisoneofthemostcomplexintegratedwaterandhydroelectricityschemesintheworld.TheSchemecollectsandstoresthewaterthatwouldnormallyfloweasttothecoastanddivertsitthroughtrans-mountaintunnelsandpowerstations.ThewateristhenreleasedintotheMurrayandMurrumbidgeeRiversforirrigation.TheSnowyMountainsSchemecomprisessixteenmajordams,sevenpowerstations(twoofwhichareunderground),apumpingstation,145kmofinter-connectedtrans-mountaintunnelsand80kmofaqueducts.TheSnowyMountainsHydro-electricSchemeprovidesaround70percentofallrenewableenergythatisavailabletotheeasternmainlandgridofAustralia,aswellasprovidingpeakloadpower(SnowyHydro2007).

Figure 8.8 AverageannualrainfallacrossAustraliasource: BureauofMeteorology


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ThehydroelectricitygenerationsysteminTasmaniacomprisesanintegratedschemeof28powerstations,numerouslakesandover50largedams.HydroTasmania,theownerofthemajorityofthesehydroelectricityplants,suppliesbothbaseloadandpeakpowertotheNationalElectricityMarket(NEM),firstlytoTasmaniaandthentheAustraliannetworkthroughBasslink,theunderseainterconnectorwhichrunsunderBassStrait.

8.3.2HydroelectricitymarketAustraliahasdevelopedmuchofitslargescalehydroenergypotential.ElectricitygenerationfromhydrohasdeclinedinrecentyearsbecauseofanextendedperiodofdroughtineasternAustralia,wheremosthydroelectricitycapacityislocated.HydroenergyisbecominglesssignificantinAustralia’sfuelmixforelectricitygeneration,asgrowthingenerationcapacityisbeingoutpacedbyotherfuels.

Primary energy consumptionAshydroenergyresourcesareusedtoproduceelectricity,whichisusedineithergridoroff-gridapplications,hydroenergyproductionisequivalenttohydroenergyconsumption.Hydroaccountedfor0.8

percentofAustralia’sprimaryenergyconsumptionin2007–08.Hydroelectricitygenerationdeclinedatanaverageannualrateof4.2percentbetween1999–2000and2007–08,theresultofaprolongedperiodofdrought.

Electricity generationIn2007–08,Australia’shydroelectricitygenerationwas12.1TWhor4.5percentoftotalelectricitygeneration(figure8.10).Overtheperiod1977–78to2007–08,hydroelectricitygenerationhastendedtofluctuate,reflectingperiodsofbeloworaboveaveragerainfall.However,theshareofhydrointotalelectricitygenerationhassteadilydeclinedoverthisperiodreflectingthehighergrowthofalternativeformsofelectricitygeneration.

TasmaniahasalwaysbeenthelargestgeneratorofhydroelectricityinAustralia,accountingfor57percentoftotalgenerationin2007–08(figure8.11).NewSouthWalesisthesecondlargest,accountingfor22percentoftotalelectricitygenerationin2007–08(sourcedmostlyfromtheSnowyMountainsHydro-electricScheme).Victoria,QueenslandandWesternAustraliaaccountfortheremainder.

Figure 8.9 MajorAustralianoperatinghydroelectricfacilitieswithcapacityofgreaterthan10MW.Numbersindicatesitesreferredtoinsection8.4.2

source: GeoscienceAustralia


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hTW

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1977-78 1982-83 1987-88 1992-93 1997-98 2002-03 2007-08

Year

Share of total electricity generation (%)AERA 8.10

Figure 8.10 Australia’shydrogenerationandshareoftotalelectricitygeneration

source: ABARE2009a

New South Walesand ACT 21.9%

Tasmania56.9% Victoria

13.1%

Queensland7.7%

WesternAustralia

0.4% AERA 8.11

Figure 8.11 Australia’shydroconsumptionbystate,2007–08

source: ABARE2009a

Western Australia andSouth Australia 0.4%

Victoria8.9%

Tasmania New South Wales28.7% and ACT 53.7%

a) State

Queensland8.3%

>500 MW, 3

50-100MW, 16

<10 MW, 60

10-50MW, 20

AERA 8.12

b) Size

250-500MW, 5

100-250MW, 8

AERA 8.12

>500 MW, 3

50-100MW, 16

10-50MW, 20

<10 MW, 60

b) Size

100-250MW, 8

250-500MW, 5

New South Walesand ACT 53.7%

Tasmania28.7%

Queensland8.3%

Victoria8.9%

Western Australia andSouth Australia 0.4%

a) State

Figure 8.12 Installedhydrocapacitybystateandsize,2009source: GeoscienceAustralia

Installed electricity generation capacityAustraliahasonly3hydroelectricityplantswith

acapacityof500MWormore,allofwhicharelocated

intheSnowyMountainsHydro-electricScheme(figure

8.12).ThelargesthydroelectricityplantinAustralia

hasacapacityof1500MW,whichismid-sizedby

internationalstandards.Morethan75percent

ofAustralia’sinstalledhydroelectricitycapacityis

containedin16hydroelectricityplantswithacapacity

of100MWormore.Attheotherendofthescale,

therearesome60smallandmini-hydroelectricityplants(lessthan10MWcapacity)withacombinedcapacityofjustover150MW.

However,installedhydroelectricitygenerationcapacitydoesnotdirectlyreflectactualelectricitygeneration.ThesmallerinstalledcapacityinTasmaniaproducesmorethandoubletheoutputoftheSnowyMountainsHydro-electricScheme.Tasmaniaistheonlystatethatuseshydroelectricityasthemainmeansofelectricitygeneration.


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8.4Outlookto2030forAustralia’shydroenergyresourcesandmarketAlthoughbenefitingfromtheRenewableEnergyTargetandincreaseddemandforrenewableenergy,growthinAustralia’shydroelectricitygenerationisexpectedtobelimitedandoutpacedbyotherrenewables,especiallywindenergy.Futuregrowthinhydroelectricitygenerationcapacityislikelytocomemainlyfromtheinstallationofsmallscaleplants.WateravailabilitywillbeakeyconstraintonthefutureexpansionofhydroelectricityinAustralia.

8.4.1KeyfactorsinfluencingtheoutlookOpportunitiesforfurtherhydroelectricitygenerationinAustraliaareofferedbyrefurbishmentandefficiencyimprovementsatexistinghydroelectricityplants,andcontinuedgrowthofsmall-scalehydroelectricityplantsconnectedtothegrid.Hydroelectricitygenerationisalow-emissionstechnology,butfuturegrowthwillbeconstrainedbywateravailabilityandcompetitionforscarcewaterresources.

Hydroelectricity is a mature renewable electricity generation technology with limited scope for further large scale development in australiaMostofAustralia’sbestlargescalehydroenergysiteshavealreadybeendevelopedor,insomecases,arenotavailableforfuturedevelopmentbecauseofenvironmentalconsiderations.ThereissomepotentialforadditionalhydroenergygenerationusingthemajorriversofnorthernAustraliabut

thisislimitedbytheregion’sremotenessfrominfrastructureandmarketsandtheseasonalflowsoftherivers.

Upgrading and refurbishing ageing hydro infrastructure in australia will result in capacity and efficiency gainsManyofAustralia’shydroelectricpowerstationsarenowmorethan50yearsoldandwillrequirerefurbishmentinthenearfuture.Thiswillinvolvesignificantexpenditureoninfrastructure,includingthereplacementandrepairofequipment.Therefurbishmentofplantswillincreasetheefficiencyanddecreasetheenvironmentalimpactsofhydroelectricity.Furthertechnologydevelopmentswillbefocusedonefficiencyimprovementsandcostreductionsinbothnewandexistingplants(box8.2).

TheSnowyHydroSchemeiscurrentlyundergoingamaintenanceandrefurbishmentprocess,atacostofapproximatelyA$300million(inrealterms)oversevenyears(SnowyHydro2009).Themodernisationwillincludethereplacementofageingandhighmaintenanceequipment,increasingtheefficiencyandcapacityofturbines,andensuringthecontinuedreliableoperationofthecomponentsystemsofthescheme.

RefurbishmentofthepowerstationatlakeMargaret,Tasmania–oneofAustralia’soldesthydroelectricityfacilities(commissionedin1914)–commencedin2008.Themainobjectiveoftheprojectwastorepairtheoriginalwoodenpipeline,whichhaddeteriorated

Box 8.2HyDROElECTRICITyCOSTS

Hydroelectricity generation costs Themostsignificantcostindevelopingahydroresourceistheconstructionofthenecessaryinfrastructure.Infrastructurecostsincludethedamsaswellasthepowerplantitself.Buildingtheplantonanexistingdamwillsignificantlyreducecapitaloutlays.Costsincurredinthedevelopmentphaseofahydrofacilityinclude(Forouzbakhshet.al.2007):

• Civil costs–constructionofthecomponentsoftheprojectincludingdams,headponds,andaccessroads.

• Electro mechanical equipment costs–themachineryofthefacility,includingturbines,generatorsandcontrolsystems.

• Power transmission line costs –installationofthetransmissionlines.

Indirectcostsincludeengineering,design,supervision,administrationandinflationimpactsoncostsduringtheconstructionperiod.Constructionofsmallandmediumplantscantakebetween1to

6years,whileforlargescaleplantsitcantakeupto30years(forexample,theSnowyHydroSchemetook25yearstobuild).

ThecostsofbuildingAustralianhydroelectricitygenerationplantshavebeenvaried.TheSnowyHydroscheme,Australia’slargesthydroelectricityscheme,wasconstructedoveraperiodof25yearsatacostofA$820million(SnowyHydro2007).Australia’smostrecentmajorhydroelectricdevelopment,theBogongproject(site1,figure8.9),commencedconstructionin2006andwascommissionedinlate2009atacostofaround$234million.Theproject–whichincludesthe140MWBogongpowerstation,a6.9kmtunnel,headworksanda220kVtransmissionline–willprovidefastpeakingpower.Incomparison,theOrdRiverhydroelectricityscheme,whichwasbuiltontheexistingdamwhichcreatedlakeArgyleinWesternAustralia,wasconstructedatacostofA$75million(PacificHydro2009).Whilethisplantisrelativelysmall


236

(30MW),itdemonstratesthepotentialreductioninconstructioncostswhereanexistingdamcanbeused.

Whilehydroelectricityhashighconstructionandinfrastructurecosts,ithasalowcostofoperationcomparedtomostothermeansofelectricitygeneration.IntheOECD,capitalcostsofhydroelectricplantsareestimatedatUS$2400perkW,andoperatingcostsareestimatedatbetweenUS$0.03andUS$0.04perkWh(IEA2008).Fornon-OECD

countries,capitalcostsareoftenbelowUS$1000

perkW.Theoperatingcostsofsmallhydroelectricity

facilitiesareestimatedatbetweenUS$0.02and

US$0.06perkWh.Operatingandcapitalcosts

dependonthesizeandtype(forexample,run-of-river)

ofplant,andwhetheritincludespumpedstorage

capabilities.Mosthydroelectricplantshavealifetime

ofover50years,duringwhichminimalmaintenance

orrefurbishmentisrequired,sotherelativelyhigh

capitalcostsareamortisedoveralongperiod.

(HydroTasmania2008).Theprojectinvolvedadditionalmaintenanceonthedam,minorupgradeofthemachines,aswellasreplacementofatransformer.Thisupgrade,completedinlate2009,costabout$14.7milliontogain8.4MWofcapacityatacapitalspendrateof$1.75millionperMW,considerablylessthanthecostsofnewplant.WorkhascommencedontheredevelopmentofthelowerMargaretPowerStation(HydroTasmania2009).

small scale hydro developments are likely to be an important source of future growth in australiaWiththeexceptionoftheBogongproject(seeProposeddevelopmentprojectsinsection8.4.2),mosthydroelectricityplantsinstalledinAustraliainrecentyearshavebeenminihydroschemes.Theseplantshavetheadvantageoflowerwaterrequirementsandasmallerenvironmentalimpactthanlargerschemes,especiallythosewithlargestoragedams.

AlthoughmostofAustralia’smostfavourablehydroelectricitysiteshavebeendeveloped,minihydroelectricityplantsarepotentiallyviableonsmallerriversandstreamswherelargedamsarenottechnicallyfeasibleorenvironmentallyacceptable.Theycanalsoberetro-fittedtoexistingwaterstorages.Atpresentminihydroplantsaccountforonlyaround2percentofinstalledhydrocapacity.Research,developmentanddemonstrationactivityislikelytoincreasethecostcompetitivenessofsmallscalehydroschemesinthefuture(box8.3).

surface water availability and competition for scarce water resources will be a key constraint to future hydro developments in australia Australiahasahighvariabilityofrainfallacrossthecontinent(figure8.8).Thismeansthatannualinflowstostoragescanvarybyupto50percentandseasonalvariationscanbeextreme.OngoingdroughtinmuchofsoutheasternAustraliahasseenasubstantialdeclineinwaterlevelsinthemajorstoragesinNewSouthWales(notablytheSnowyMountainsscheme),VictoriaandTasmaniaanddecliningcapacityfactorsforhydroelectricitystations.WaterlevelsinstoragesacrossAustraliahavedeclined

toanaverageofbelow50percentofcapacity(NationalWaterCommission2007).CloudseedinghasbeenusedintheSnowyMountainsandinTasmaniatoaugmentwatersupplies.

ClimatechangemodelssuggesttheoutlookforsoutheasternAustraliaisfordrierconditionswithreducedrainfallandhigherevaporation,andahigherfrequencyoflargestorms(BOM2009;IPPC2007;Batesetal.2008).Reducedprecipitationandincreasedevaporationareprojectedtointensifyby2030,leadingtowatersecurityproblemsinsouthernandeasternAustraliainparticular(Hennessyetal.2007).TheclimatechangeprojectionsfurtherexacerbatetheproblemofAustralia’sdryclimatewithlowandvariablerainfall,lowrunoffandunreliablewaterflowsandmeanthatthereisonlylimitedpotentialforfurthermajorhydrodevelopmentinmainlandAustralia.SomeofthispotentialislocatedintheriversinnorthernAustralia,butthisislimitedbytheinconsistencyofwaterflowsinthisregion(periodsoflowrainfallalongwithperiodsofflooding).

Competitionforwaterresourceswillalsoaffecttheavailabilityofwaterforhydroelectricitygeneration.Demandforwaterforurbanandagriculturalusesisprojectedtoincrease.Itislikelythattheseusesforscarcewaterresourceswilltakeprecedenceoverhydroelectricitygeneration.Generatorsfaceincreasingdemandstobalancetheirneedsagainsttheneedforgreaterwatersecurityforcitiesandmajorinlandtowns.Themaintenanceofenvironmentalflowstoensuretheenvironmentalsustainabilityofriversystemsbelowdamsisalsoanimportantfutureconsiderationwhichmayfurtherconstraingrowthofhydroelectricitygeneration.

WaterpoliciesmayalsoplayaroleinthefuturedevelopmentofhydroelectricityinAustralia.Policiesthatlimittheavailabilityofwatertohydroelectricitygenerators,restricttheflowofwaterintodams,requiregeneratorstoletwateroutofdams,orprioritisetheuseofwaterforagriculturecouldchangetheviabilityofmanyhydroelectricgenerators,andlimitfuturegrowth.TheextendeddroughtinmuchofAustraliahasledtowaterrestrictionsbeingputintoplaceinmostcapitalcities,andregulationoftheMurray-Darlingbasinriversystemshasstrengthened.


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Box 8.3TECHNOlOGyDEVElOPMENTSINHyDROElECTRICITy

Researchisbeingundertakentoimprove

efficiency,reducecosts,andtoimprovethe

reliabilityofhydroelectricitygeneration.There

aredifferentresearchneedsforsmallandlarge

scalehydro(table8.3).Smallhydropowerplants,

includingmicroandpicoplants,areincreasingly

seenasaviablesourceofpowerbecauseoftheir

lowerdevelopmentcostsandwaterrequirements,

andtheirlowerenvironmentalfootprint.Smallscale

hydropowerplantsrequirespecialtechnologies

toincreasetheefficiencyofelectricitygeneration

andtherebyminimiseboththeoperatingcosts

andenvironmentalimpactsofhydroelectricity

generation(ESHA2006).

Theenvironmentalimpactsofhydroelectricity

arealsobeinginvestigated,andwaystomitigate

theseimpactsdeveloped.Thisincludesthe

developmentofnewandimprovedturbines

designedtominimisetheimpactonfishandother

aquaticlifeandtoincreasedissolvedoxygeninthe

water.Theintroductionofgreaselessbearingsintheturbineswouldreducetheriskofpetroleumproductsenteringthewater,andisalsocurrentlybeinginvestigated(EERE2005).

Table 8.3 Technologyimprovementsforhydropower

Large hydro small hydro

Equipment Equipment low-headtechnologies, Turbineswithlessimpactincludingin-streamflow onfishpopulationsCommunicateadvances low-headturbinesinequipment,devicesand In-streamflowtechnologiesmaterials

operation and maintenance operation and maintenance Increasinguseof Developpackageplantsmaintenance-free requiringonlylimitedandremoteoperation operationandmaintenancetechnologies

Hybrid systems Wind-hydrosystemsHydrogen-assistedhydrosystems

source: IEA2008

8.4.2OutlookforhydroelectricitymarketHydroelectricityisprojectedtocontinuetobeanimportantsourceofrenewableenergyinAustraliaovertheoutlookperiod.

InABARE’slatestlong-termenergyprojectionsthatincludetheRenewableEnergyTarget,a5percentemissionsreductiontargetandothergovernmentpolicies(ABARE2010),hydroelectricitygenerationisprojectedtoincreaseonlyslightlybetween2007–08and2029–30,representinganaverageannualgrowthrateof0.2percent.In2029–30,hydroisprojectedtoaccountfor3.5percentofAustralia’stotalelectricitygeneration,and0.6percentofprimary

energyconsumption(figure8.13).Thepotentialforreturnofhydroelectricityoutputtopre-2006levelswillbestronglyinfluencedbyclimateandbywateravailability.

Proposed development projectsBasedonHydropowerandDams(2009),thereareseveralcurrenthydroprojectdevelopmentsinAustralia:

• A20MWhydroplantiscurrentlyunderconstructionattheDartmouthregulatingdaminVictoria(Site2,figure8.9).

• Thenextstageofredevelopmentofthe8.4MWlakeMargaretpowerstationinTasmaniahasbeenapprovedbytheboardofHydroTasmania(Site3,figure8.9).

• HydroTasmaniaConsultinghasbeenawardedacontracttosupplyandconstructsixminihydroplantsforMelbourneWaterwithatotalcapacityof7MW,producingupto40GWhperyear.

8.5ReferencesABARE(AustralianBureauofAgriculturalandResourceEconomics),2009a,AustralianEnergyStatistics,Canberra,August

ABARE,2009b,Majorelectricitydevelopmentprojects–Octoberlisting,Canberra,November

ABARE,2010,Australianenergyprojectionsto2029–30,ABAREresearchreport10.02,preparedfortheDepartmentofResources,EnergyandTourism,Canberra

GeoscienceAustralia,2009,mapofoperatingrenewableenergygeneratorsinAustralia,Canberra

%

4

3

2

1

0

5

6

7

Year

8

9

hTW

0

14

12

10

8

6

4

2

16

18

1999-00 2001-02 2003-04 2005-06 2007-08 2029-30

Electricity generation(TWh)

AERA 8.2

Share of total electricitygeneration (%)

Figure 8.13 Australia’shydroelectricitygenerationto2029–30source: ABARE2009a,2010


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BatesBC,KundzewiczZW,WuS&PalutikofJP(eds),2008,Climatechangeandwater,IPCCTechnicalPaperVI,IPCCSecretariat,Geneva,<http://www.ipcc.ch/publications_and_data/publications_and_data_technical_papers_climate_change_and_water.htm>

BureauofMeteorology(BOM),2009,TheGreenhouseEffectandClimateChange,BOM,Melbourne,<http://www.bom.gov.au/info/GreenhouseEffectAndClimateChange.pdf>

EERE,2005,Hydropowerresearchanddevelopment,EnergyEfficiencyandRenewableEnergy,USDepartmentofEnergy,Washington,August

EgreD&MilewskiJ,2002,Thediversityofhydropowerprojects,EnergyPolicy,vol.30,pp.1225–1230

ESHA,2006,StateoftheArtofSmallHydropowerinEU-25,EuropeanSmallHydropowerAssociation,Belgium

ForouzbakhshF,HosseiniSMH&VakilianM,2007,Anapproachtotheinvestmentanalysisofsmallandmediumhydro-powerplants,EnergyPolicy,vol.35,pp.1013–1024,Elsevier,Amsterdam

HennessyK,FitzharrisB,BatesBC,HarveyN,HowdenSM,Hughesl,SalingerJ&Warrick,R,2007,AustraliaandNewZealand.ClimateChange2007:Impacts,AdaptationandVulnerability.ContributionofWorkingGroupIItotheFourthAssessmentReportoftheIntergovernmentalPanelonClimateChange,MlParry,OFCanziani,JPPalutikof,PJvanderlindenandCEHansoneds.,CambridgeUniversityPress,Cambridge,UK,507-540

HydropowerandDams,2009,WorldAtlas2008,TheInternationalJournalonHydropower&Dams,Aqua~MediaInternational,Surrey

HydroTasmania,2008,lakeMargaretPowerScheme,Hobart,<http://www.hydro.com.au/documents/Energy/lake_Margaret_FAQ_200811.pdf>

HydroTasmania,2009,AnnualandSustainabilityReport,2009,<http://www.hydro.com.au/documents/Corporate/Annual%20Reports/2009/Hydro_AR.html>

IEA(InternationalEnergyAgency),2008,Energytechnologyperspectives:scenariosandstrategiesto2050,OECD,Paris

IEA,2009a,WorldEnergyBalances,2009,OECD,Paris

IEA,2009b,WorldEnergyOutlook2009,OECD,Paris

IEA,2009,WorldEnergyOutlook,OECD,Paris

IntergovernmentalPanelonClimateChange(IPCC),2007,IPCCFourthAssessmentReport:ClimateChange2007(AR4),Geneva,<http://www.ipcc.ch/publications_and_data/publications_and_data_reports.htm>

NationalWaterCommission,2007,AbaselineassessmentofwaterresourcesfortheNationalWaterInitiative–level2Assessment,Canberra,May

PacificHydro,2009,OrdRiverHydrofactsheet,Melbourne,<http://www.pacifichydro.com.au/en-us/our-projects/australia--pacific/ord-river-hydro-project.aspx>

PaishO,2002,Smallhydropower:technologyandcurrentstatus.RenewableandSustainableEnergyReviews,vol.6,pp.537–556,Elsevier,Amsterdam

Ren21,2009,Renewablesglobalstatusreport,2009update,RenewableEnergyPolicyNetworkforthe21stCentury,Paris

SnowyHydro,2007,SnowyMountainsScheme,Sydney,<http://www.snowyhydro.com.au/levelTwo.asp?pageID=66&parentID=4>

SnowyHydro,2009,SchemeModernisationProject,Sydney,<http://www.snowyhydro.com.au/levelTwo.asp?pageID=340&parentID=4>

WEC(WorldEnergyCouncil),2007,SurveyofEnergyResources2007,london,September

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