chapter 11 ocean energy - geoscience australia · 2020. 6. 18. · current ocean energy use is...
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Chapter 11Ocean Energy
11.1Summary
K E y m E s s a g E s
• Oceanenergy–wave,tideandoceanthermalenergysources–isanunderdevelopedbutpotentiallysubstantialrenewableenergysource.
• Australiahasworld-classwaveenergyresourcesalongitswesternandsoutherncoastline,especiallyinTasmania.
• Australia’sbesttidalenergyresourcesarelocatedalongthenorthernmargin,especiallythenorth-westcoastofWesternAustralia.
• Worldwide,oceanenergyaccountsforanegligibleproportionoftotalelectricitygeneration.Theshareofoceanenergyinworldelectricitygenerationisprojectedtoincreaseby2030,albeitonlymodestly.
• Currentoceanenergyuseismainlybasedontidalpowerstations.Waveenergytechnologiesareatearlystagesofcommercialisationandoceanthermaltechnologiesarestillatdevelopmentstage.
• AdoptionofoceanenergyinAustraliadependsontechnologiesfortidalorwaveenergyprovingcommerciallyviable.Thecostofaccesstothetransmissiongridmayalsobeanimpedimentformanysites.
11.1.1 World ocean energy resources and market • Therearesubstantialocean(tidal,waveandocean
thermal)energyresourcesthathavepotentialforzeroorlowemissionelectricitygeneration.
• Oceanenergyindustriesareatanearlystageofdevelopment,andtheyarecurrentlythesmallestcontributorstoworldelectricitygeneration.CommercialapplicationsofoceanenergyhavebeenlimitedtotidalbarragepowerplantsintwoOECDcountries,France(240MW)andCanada(20MW),butmajornewtidalbarrageplantsareunderconstructionintheRepublicofKorea.
• Governmentpoliciesandfallinginvestmentcostsareprojectedtobethemainfactorsunderpinningfuturegrowthinworldoceanenergyuse.WorldelectricitygenerationfromoceanenergyisprojectedbytheIEAinthereferencecasetoincreaseatanaverageannualrateof14.6percentbetween2007and2030.
11.1.2Australia’soceanenergyresources• ThenorthernhalfoftheAustraliancontinental
shelfhaslimitedwaveenergyresources,buthassufficienttidalenergyresourcesforlocalelectricityproductioninmanyareas,particularlytheNorthwestShelf,Darwin,TorresStraitandthesouthernGreatBarrierReef(figure11.1).
• ThesouthernhalfoftheAustraliancontinentalshelfhasworld-classwaveenergyresourcesalongmostofthewesternandsoutherncoastlines,particularlythewestandsoutherncoastsofTasmania(figure11.2).Incontrast, tidalenergyresourcesarelimitedinthisregion.
• AreasinthePacificOceanareprospectiveforoceanthermalenergy.
11.1.3KeyfactorsinutilisingAustralia’socean energy resources• Productioncostsforoceanenergysystems
arecurrentlyhigh,butareexpectedtofallastechnologiesmature.TheproductioncostsofoceanenergytechnologiesareestimatedbytheIEAtorangefromUS$60perkWtoUS$300perkW(in2005dollars),withtidalbarragesystems atthelowerendofthisrangeandtidalcurrent andwavesystemsatthehigherend.
• Giventhelargelypre-commercialstatusofthecurrentoceanenergysystems,theoutlookishighlydependentonresearch,developmentanddemonstration(RD&D)activitiesandtheoutcomesoftheseactivities,bothinassessingenergypotentialanddevelopinglow-costenergyconversiontechnologies.
• GovernmentpoliciesthatencourageRD&DwillbeanimportantdriverofthefuturedevelopmentofoceanenergytechnologiesinAustralia.
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• ManyofAustralia’sbesttidalandwaveenergyresourcesareinareasdistantfromtheelectricitygrid.Theproximityoftheresourcetomajorpopulationcentresandtheelectricitygridappearstobesomewhatbetterforwaveenergythantidaloroceanthermalenergy.
• SomeofAustralia’sbesttidalenergyresourcesarealsolocatedinenvironmentallysensitiveareasandtherearesignificantenvironmentalimpactsassociatedwithtidalenergysystems.
• Newtidaltechnologiesbasedontheuseoftidalcurrentshaveenvironmentaladvantagesovertidalbarragesystems,but,likewaveandoceanthermalenergysystems,arestillatanearlystageofdevelopment.
11.1.4Australia’soceanenergymarket• Oceanenergytechnologiesarestillatanearly
stageofdevelopmentandhaveonlybeenusedatapilotscaleinAustralia.Fourtidalorwaveenergyplants,withacombinedcapacityoflessthan1MW,havebeendevelopedinrecentyears.
• Therearealsoplanstodevelopseveralcommercialscaletidalandwaveenergy
projectsinAustralia.Ifsuccessful,these
projectscouldleadtocommercialscaleplants
generatingelectricityforthegrid,foroff-gridlocal
domesticandindustrialuse,ortopowerwater
desalinationplants.
11.2Backgroundinformationandworldmarket
11.2.1DefinitionsTherearetwobroadtypesofoceanenergy:
mechanicalenergyfromthetidesandwaves,and
thermalenergyfromthesun’sheat.Inthisreport,
oceanenergyisclassifiedastidalenergy,wave
energyandoceanthermalenergy.Potentialenergy
resourcesassociatedwithmajoroceancurrents,
suchastheEastAustraliaCurrentortheLeeuwin
Current,arenotconsideredhere.
Tidal energy Tidesresultfromthegravitationalattractionofthe
Earth-Moon-SunsystemactingontheEarth’soceans.
Tidesarelongperiodwavesthatresultinthecyclical
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0 750 km
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10°
20°
30°
130° 140° 150°
Tidal energy (GJ/m2)2
40°
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Figure 11.1 Totalannualtidekineticenergy(ingigajoulespersquaremetre,GJ/m2)ontheAustraliancontinentalshelf(lessthan300mwaterdepth)
Note: Thelowrangeofthecolourscaleisaccentuatedtoshowdetail.Thecolourscalesaturatesat2GJ/m2butthemaximumvaluepresent is195GJ/m2
source: GeoscienceAustralia
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CHAPTER 11: OCEAN ENERGY
riseandfalloftheocean’ssurfacetogetherwithhorizontalcurrents.Therotatingtidewavesresultindifferentsealevelsfromoneplaceonthecontinentalshelftothenextatanyonetime,andthiscausesthewatercolumntoflowhorizontallybackandforth(tidalcurrents)overtheshelfwiththetidaloscillationsinsealevel.
Tidal energyisenergygeneratedfromtidalmovements.Tidescontainbothpotentialenergy,relatedtotheverticalfluctuationsinsealevel,andkineticenergy,relatedtothehorizontalmotionof thewatercolumn.Itcanbeharnessedusingtwomaintechnologies:
• Tidal barrages (or lagoons) are based on the rise and fall of the tides–thesegenerallyconsistofabarragethatenclosesalargetidalbasin.Waterentersthebasinthroughsluicegatesin thebarrageandisreleasedthroughlow-headturbinestogenerateelectricity.
• Tidal stream generators are based on tidal or marine currents–thesearefree-standingstructuresbuiltinchannels,straitsoronthe shelfandaredesignedtoharnessthekineticenergyofthetide.Theyareessentiallyturbines
thatgenerateelectricityfromhorizontallyflowingtidalcurrents(analogoustowindturbines).
Wave energy Waves (swell)areformedbythetransferofenergyfromatmosphericmotion(wind)totheoceansurface.Waveheightisdeterminedbywindspeed,thelengthoftimethewindhasbeenblowing,thefetch(distanceoverwhichthewindhasbeenblowing),andthedepthandtopographyoftheseafloor.Largestormsgeneratelocalstormwavesandmoredistantregularwaves(swell)thatcantravellongdistancesbeforereachingshore.
Wave energyisgeneratedbyconvertingtheenergyofoceanwaves(swells)intootherformsofenergy(currentlyonlyelectricity).Itcanbeharnessedusingavarietyofdifferenttechnologies,severalofwhicharecurrentlybeingtrialledtofindthemostefficientwaytogenerateelectricityfromwaveenergy.
Ocean thermal energy Oceanscovermorethan70percentoftheEarth’ssurface.Thesun’sheatresultsinatemperaturedifferencebetweenthesurfacewateroftheoceananddeepoceanwater,andthistemperaturedifferencecreatesoceanthermalenergy.
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0 750 km
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20°
30°
130° 140°
40°
150°120°
Wave energy (TJ/m)1.5
0
Figure 11.2 Totalannualwaveenergy(inTerrajoulespermetre,TJ/m)ontheAustraliancontinentalshelf(lessthan300mwaterdepth)
source: GeoscienceAustralia
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Ocean thermal energy conversion (OTEC)isameansofconvertingintousefulenergythetemperaturedifferencebetweensurfacewaterandwateratdepth.OTECplantsmaybeusedforarangeofapplications,includingelectricitygeneration.Theymaybeland-based,floatingorgrazing.
Moredetailedinformationontidal,waveandoceanthermalenergytechnologiesisprovidedinBox11.2insection11.4.
11.2.2OceanenergysupplychainFigure11.3providesaschematicrepresentationofthepotentialtidal,waveandoceanthermalenergyindustryinAustralia.Oceanenergyresourceshavethepotentialtogenerateelectricityusingvarioustypesofturbinesandotherenergyconverters.Theelectricitygeneratedcouldbeusedeitherlocally,orfedintotheelectricitygrid.Aswellaselectricitygeneration,someoceanenergyresourcescanbeusedforotherpurposessuchaspumpingseawaterthroughdesalinationplantstogeneratepotablewater.
Thesupplyoftidal,waveandoceanthermalenergyrequiresfirstlyidentifyingthesiteswiththebestenergyresourcesmatchedtotheenergyconvertertechnologybeingconsidered,sothattheirpotentialforgeneratingelectricitycanbedetermined.Whetherornotapotentialprojectthenproceedstodevelopmentwillrequiredetailedeconomicassessment,includingfactorssuchasthecapitalandoperatingcosts,accesstofinance,thecostofgridconnection,ifrelevant,includingtransmissiondistancesandassociatedlosses,environmentalandcommunityissuesandthepricereceivedfortheenergy generated.
11.2.3WorldoceanenergymarketThereisonlyasmallmarketatpresentfortidal,waveandoceanthermalenergy.In2009,commercialapplicationswerelimitedtoelectricitygenerationbasedontidalenergyresourcesinFranceandCanadabutsignificantinvestmentinnewtidalenergyprojectswastakingplaceintheRepublicofKorea.FeasibilityassessmentsandRD&Dinvestmentsinoceanenergytechnologiesaretakingplaceinseveralcountries.
Resources
Tidal energy Thetidalenergyresourceisvastandsustainable.However,theeconomicallyexploitableresourceiscurrentlysmallbecauseoftheconsiderablecostsassociatedwithenergyextractionandtheenvironmentalimpactsofsometidalenergytechnologies,notablybarragesandlagoons(tidalpools).Therearefewestimatesoftheworldtidalenergyresourcepotential.
Wave energy Theglobalwavepowerresourceindeepwater(100mormore)hasbeenestimatedat1–10TW andtheeconomicallyexploitableresourcecould beashighas2000TWhperyear(WEC2007). Theaverageannualwavepoweracrosstheworld isshowninfigure11.4.Someofthecoastlines withthegreatestwaveenergypotentialarethewesternandsoutherncoastsofSouthAmerica,SouthAfricaandAustralia.Thesecoastsexperiencethewavesgeneratedbythewesterlywindbeltbetweenlatitudes40°and50°south,whichare
Processing, Transport,Resources Exploration End Use Market
Storage
Industry
Commercial
Residential
ElectricityGeneration
AERA 11.3
Development andProduction
Developmentdecision
Project
Domesticmarket
(proposed)Resource definitionand site location forspecific technology
Figure 11.3 Australia’soceanenergysupplychainsource: ABAREandGeoscienceAustralia
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CHAPTER 11: OCEAN ENERGY
blowingoveraneffectivelyinfinitefetch.Thisproducessomeofthelargestandmostpersistentwaveenergylevelsglobally.
Ocean thermal energy Atpresent,itisnotpossibletoquantifyoceanthermalenergyresourcepotential(WEC2007).Figure11.5showsthetemperaturedifferencebetweenthesurfacewateroftheoceansintropicalandsubtropicaareas,andwateratadepthofaround1000metreswhichissourcedfromthepolarregions(WEC2007).
l
OTECmaybeusedincircumstanceswheretherearetemperaturedifferencesofatleast20°C.
Primary energy consumptionOceanenergyiscurrentlyonlyusedtogenerateelectricityandhenceprimaryenergyconsumptionofoceanenergyisthesameasfuelinputstoelectricitygeneration.Worldoceanenergyusedecreasedatanaverageannualrateof1.4percentbetween2000and2008,andaccountedforonlyaverysmallproportionoftotalprimaryenergyconsumption
2724
2950
89 7040 2849 9268 102 41
22 49 651231 48 18100 38 33 38 3013 26 12 4219 5 5030 1217 15 19 8
12 10 17 2013 18
11 13 11 3412 149 1015 1716 21 1245 402320 15 26 2934 1024
33 23 38 43 3740 25 3866 50 78 7550 82 63 7233 818474 4372
4297 97
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120°W 60°W 0° 60°E 120°E
60°N
30°N
0°
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Figure 11.4 Averageannualwavepowerlevels(inkW/m)source: WorldEnergyCouncil2007
2422
20
1618
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0°
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0 5000 kmTemperature difference (°C)
16
18
20
22
24
120°E60°E0° 30°N
0°
120°W 60°W
30°S
Figure 11.5 Theareasavailableforoceanthermalenergyconversion(OTEC)andthetemperaturedifference(measuredin°C)
source: WorldEnergyCouncil2007
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(table11.1).Tidalenergyhasbeenutilisedon acommercialscaletodateonlyinOECDcountries.
Electricity generationIn2008,544GWh(0.5TWh)ofelectricitywasgeneratedfromocean(tidal)energy,representingonly0.003percentofworldelectricitygeneration(figure11.6).OceanenergyhasbeengeneratedfromtidalenergyplantsinFranceandCanada;
• France,themainoceanenergyproducingcountry,
produced1.8PJ(512GWh)commerciallyin2007
and2008.A240MWtidalbarragepowerplanthas
beenoperatingatLaRanceinFrancesince1966
andiscurrentlythelargesttidalpowerstationin
theworld.Itwillbeovertakenwhenthe260GW
tidalenergypowerplantatLakeSihwa,nearSeoul,
RepublicofKoreaiscommissionedin2010.
• Canadaproduced0.1PJ(35GWh)in2007and
2008.Canadahasa20MWtidalbarragepower
plantinAnnapolisRoyal,NovaScotia,whichhas
beenoperatingsince1984.
Globally,thereissignificantRD&Dactivitythatwill
contributetothefuturecommercialisationofother
oceanenergytechnologies.Informationonglobal
RD&Dactivityisprovidedinsection11.4.
World ocean energy market outlookTheIEAprojectssomegrowthinoceanenergyproductionovertheoutlookperiodto2030,although
Table 11.1 Keyoceanenergystatistics
a
unit australia 2007–08
OECD 2008
World 2008
Primary energy consumption PJ - 2.0 2.0
Shareoftotalb % - 0.0009 0.0004
Averageannualgrowth,2000–2008 % - -1.3 -1.4
Electricity generation
Electricityoutput TWh - 0.5 0.5
Shareoftotalb % - 0.005 0.003
Electricitycapacity GW 0.0008 0.261 0.261
a EnergyproductionandprimaryenergyconsumptionareidenticalbTotalworldprimaryenergyconsumptionandelectricitygenerationdata arefor2007 source:IEA2009a
0
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0.002
0.004
0.006
0.008
0.010
0.012
%
1971 197719751973 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007
France Canada
hTW
Year
Share of total electricity generation (%)AERA 11.6
Figure 11.6 Worldwaveandtidalelectricitygenerationandshareoftotalelectricitygenerationsource: IEA2009a
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itisprojectedtoremainthesmallestsupplierofelectricity.In2030,oceanenergyisprojectedtoaccountfor0.1percentofOECDelectricitygenerationand0.04percentoftotalworldelectricitygeneration(table11.2).
MostofthegrowthisprojectedtooccurintheEuropeanUnion,whichisprojectedtoaccountforalmost70percentoftotaloceanenergyusein2030.Afurther3TWhisprojectedtobegeneratedinsmallquantitiesintheUnitedStates,CanadaandthePacific.TidalprojectscurrentlyunderdevelopmentintheRepublicofKoreaareplannedtobeproducing550GWhin2010withpotentialtoincreasesignificantlybeyondthattowardtheKoreangovernment’sgoalofproducing5TWhusingtidalpowerby2020(IEA2009b).
Table 11.2 IEAreferencecaseprojectionsforworldoceanenergyelectricitygeneration
unit 2007 2030
OECD TWh 1 12
Shareoftotal % 0.009 0.091
Averageannualgrowth % - 14.3
Non-OECD TWh 0.0 1
Shareoftotal % 0.000 0.005
Averageannualgrowth % - -
World TWh 1 13
Shareoftotal % 0.005 0.038
Averageannualgrowth % - 14.6
source: IEA2009b
11.3Australia’soceanenergyresources and market
11.3.1OceanenergyresourcesThefollowingdiscussionfocusesonAustralia’stidalenergyandwaveenergyresources.TherehasbeenlimitedprogressinassessingAustralia’soceanthermalenergyresources,notleastbecauseofthegreaterprospectivityofotherrenewableenergyresources(WEC2007).
Tidal energyAssessmentofAustralia’stidalenergyresourcesisrestrictedtothetidekineticenergypresentonAustralia’scontinentalshelf.Tidalcurrentsofftheshelfareminimal.Moreover,significanttransmissionlosseswouldbeexpectedfortidalenergyconverterslocatedfarfromshore.Thecontinentalshelfforthisassessmentisdefinedaswaterdepthslessthan300m.Detailsofthedataandmethodsusedin thisassessmentanditslimitationsaredescribed inBox11.1.
IndicativevaluesforthemeanspringtiderangearoundAustraliaareshowninfigure11.7.Avarietyoftideenergyconvertersarepresentlyavailabletogenerate
electricity.Barrage-typesystemsrequirespecificcoastalgeomorphicsettings–typicallybaysorestuaries–astheyaredesignedtoharvestthepotentialenergyofthetide,whichdependsonboththetiderangeandthesurfaceareaofthebasin(i.e.thetidalprism).Becauseoftheirsite-specificrequirementsandthecomplexresponseofthetideinveryshallowwater,itisnotpracticaltoundertakeadetailednationalscaleassessmentofthetidalpotentialenergy.Nevertheless,figure11.1identifiesinbroadtermstheregionsthatmaysupporttideenergyconvertersofthebarragetype,andthereforehighlightswheremoresite-specificstudiescouldbedirected.
Barrage-typetideenergysystemsgenerallyrequiremacro-tideranges(greaterthan4m),whicharerestrictedtothebroadnorthernshelfofAustralia;fromPortHedlandnorthwardstoDarwinandthesouthernendoftheGreatBarrierReef.Othertypesoftidalenergyconverters(tidalturbines)harnessthekineticcomponentoftideenergy.Theyaresuitableforinstallationonthecontinentalshelf,andwhiletheydonotnecessarilyrequirehighly-specificcoastalconfigurationstheycanbedeployedinlocationswherelocalcoastalconfigurationsresultinincreasedtidalflows.
ThetotaltidalkineticenergyontheentireAustraliancontinentalshelfatanyonetime,onaverage,isabout2.4PJ.ThetotalamountoftidekineticenergyontheshelfadjacenttoeachstateislistedinTable11.3.Sincethetidalmovementofshelfwatersoccupiestheentirewatercolumn,thetideenergyadjacenttoeachstateatanyonetimereflectsboththevolumeofshelfwatersandthecurrentspeedofthosewaters.Table11.3providessomeinterestingcomparisons,butitisskewedbytheNorthWest
Table 11.3 Totaltidalkineticenergy(onaverageatanyonetimeonthecontinentalshelfadjacenttoeachjurisdiction
state/Territory Total energy (TJ)
NorthernTerritory 311.63
Queensland 454.19
NewSouthWales 1.21
VictoriaandTasmania 151.41
SouthAustralia 27.15
WesternAustralia 1496.33
National Total 2441.92
Note: Thesedatawereobtainedbytakingthetime-averageofthe1-yeartimeseriesoftidekineticenergydensityavailableateachgridpoint,multiplyingbythewaterdepthandmultiplyingbytheareaofa0.1degreeby0.1degreequadrantateachgridpoint,andsummingtheresultsforallgridpointsacrosstheshelf source:GeoscienceAustralia
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Shelfregion,wherethereisalargeenergydensityduetothetiderangeandalargevolumeofwatermobilisedbythetide.Therearenumerousotherlocationsonshallowerornarrowerregionsofshelfwherethetotaltidekineticenergyisconsiderablyless,butstillmorethanenoughforthepurposeofelectricitygeneration(e.g.Darwin,TorresStraitandBassStrait).
Thespatialdistributionoftime-averagedtidalkineticenergydensityontheAustraliancontinentalshelfisshowninfigure11.8.Consistentwiththetiderangesshowninfigure11.7,theregionsofshelfthathavethelargestkineticenergydensitiesaretheNorthWestShelfandthesouthernshelfoftheGreatBarrierReef,withlargeareashavingdensitiesofmorethan100Joulespercubicmetre(J/m3).Darwin,BassStraitandTorresStraithavelocalisedareaswithsimilarenergydensities,despitemoremodesttideranges(figure11.8).Thisisduetotheconvergenceandaccelerationoftidalstreamsontheshelfbetweentheislandsandmainland.
Therateofdeliveryoftidalkineticenergy,orenergyflux,isalsoreferredtoastidal (kinetic) power.Thespatialdistributionoftime-averagedtidal(kinetic)
powerontheAustraliancontinentalshelfisshowninfigure11.9.Tidal(kinetic)powerisalsogreatestonthenorthernhalfoftheAustraliancontinentalshelf,withmanyareashavingmorethan100Wattspersquaremetre(W/m2).ThesouthernhalfoftheAustralianshelf(withtheexceptionofBassStrait)hasrelativelylittletidalkineticenergyorpower(figures11.8and11.9).Thetidalkineticenergydeliveredinagiventimeperiod,forexample,inoneyear(totalannualtidalkineticenergy),canbeobtainedbyintegratingthetidal(kinetic)powertimeseriesoveroneyear.
Thespatialdistributionoftotalannualtidekineticenergyisshowninfigure11.10.ThisannualresourceisexpressedinGJ/m2oftidalflow.Inprinciple,thetotalannualtidalkineticenergyadjacenttoeachstatecouldbeestimatedbyintegratingwithrespecttothecross-sectionalarea,butinpracticetheresultdependsonwherethecross-sectionisdrawn.
Theestimatedmaximumtime-averagetidal(kinetic)poweroccurringontheshelfadjacenttoeachstate islistedintable11.4.Themeanaswellasthe 10th,50th,and90thpercentilepoweratthatlocationislistedtogetherwiththetotaltidalkinetic
3.22.9 2.85.5 2.5
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1.79.2 1.5
1.8
8.22.4
3.6 4.9
8.21.8
3.3
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SYDNEY 1.20.7 2.0 ADELAIDE
0.4 1.31.7MELBOURNE 1.1
0.6 0.6 2.01.1
2.6 3.2
HOBART0.8
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130° 140° 150°
40°
Figure 11.7 Tideranges(inmetres)forthemainstandardportsaroundAustraliasource: AustralianNationalTideTables;AustralianHydrographicService
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energydeliveredannually.Inallcasesthemaximumtidalpoweroccursinwaterdepthslessthanorequalto50m,whichinalllikelihoodisthedepthrangeinwhichthepresentgenerationoftidalenergyconverterscouldbeinstalled.
ThebestresourcedjurisdictionsareWesternAustralia,QueenslandandtheNorthernTerritory.WesternAustraliahaslocationsoffitscoastwheretheaveragetidal(kinetic)powerinwaterdepthslessthanorequalto50mexceed6.1kWpersquaremetre(KW/m2),deliveringatotaltidalkineticenergyofover195GJ/m2 annually.
Wave energyPreviousstudiesofAustralia’swaveclimatehavefocusedmainlyontheenergeticsouth-western,southernandsouth-easternmarginsofthecontinent,buttherehasbeennopreviouspubliclyavailablecomprehensivenationalassessmentofAustralia’swaveenergyresources.ThewaveenergyresourceassessmentpresentedhereisbasedonwavedatahindcastbytheBureauofMeteorologyat6-hourlyintervalsoveranelevenyearperiodfrom24090locationsevenlydistributedoverAustralia’sentire
continentalshelf(Hasselmannetal.1988).TheassessmentmethodologyisdescribedinmoredetailinBox11.1.
Severaltypesofwaveenergyconvertersarepresentlyavailabletogenerateelectricity.Thechoiceofconvertertechnologyplaceslimitsonthelocationsfromwhichwaveenergycanbeharvested.Forexample,thePelamisdeviceiscapableofgeneratingelectricityinwaterdepthsof60to80metres,whereasCETOissuitedtoshallowerwaterdepths(15to50metres).Giventheseconsiderations,andthetransmissionlossesexpectedifawaveenergyconverteristoofarfromshore,thisresourceassessmentisrestrictedtothewaveenergypresentonAustralia’scontinentalshelf.Theshelfisdefinedhereaswaterdepthslessthan300metres.Thespatialdistributionoftime-averagedwaveenergydensityontheAustraliancontinentalshelfisshowninfigure11.11.ThenorthernAustralianshelf(i.e.abovelatitude23degreessouth)ischaracterised byrelativelylowwaveenergydensitiesofgenerallylessthan2.5kJ/m2.ThesouthernAustralianshelf,ontheotherhand,ischaracterisedbyenergy
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0 750 km
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130° 140° 150°
Tidal energy density (J/m3)100
40°
0
Figure 11.8 SpatialdistributionoftimeaveragedtidalkineticenergydensityontheAustraliancontinentalshelf (notdepthintegrated).TheenergydensityateachlocationrepresentstheaverageoveranyoneyearinJ/m3. Notethatthecolourscalesaturatesat100J/m3toshowdetail;themaximumvaluepresentis2696J/m3
source: GeoscienceAustralia
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BOx 11.1 DETAILSOFASSESSMENTMETHODS,DATAANDANALySIS:TIDALANDWAVEENERGy
Tidal energyTherearenopreviousnationalassessmentsofAustralia’stidalenergyresourcepubliclyavailable(althoughCSIRO’sMarineandAtmosphericResearchunithasworkinprogress).ThisassessmentofAustralia’stideenergyresourceisbasedonthemeanspringtidalrangescalculatedusingtheAustralianNationalTideTablesproducedbytheAustralianHydrographicService(2006)togetherwiththedepth-averagedtidalcurrentspeedpredictedusingahydrodynamicmodel.TidalcurrentsareonecomponentofGeoscienceAustralia’sGEOMACSModel(GeologicalandOceanographicModelofAustralia’sContinentalShelf).AfulldescriptionofthetidecomponentofthemodelispresentedinPorter-Smithetal.(2004).
Tidalwaterlevelsatagivensitearehighlypredictable,providedmorethanayearofmeasurementsisavailable.Thetidalrangespresentedinfigure11.7areallfromstandardportswithlong-termtidegaugesinstalled,andarethereforeconsideredsufficientlyreliableforuseintheresourceassessment.Thepredictionoftidalwaterlevelsatsiteswherenotidegaugemeasurementsexistislessstraightforward.Theaccuracythendependsonthenatureofthehydrodynamicmodelusedandthecomplexityoftheshelfandcoastalbathymetry.Predictionsoftidalcurrentsareevenmoresensitivetothesenaturalcomplexities.Thehydrodynamicmodelusedinthisassessmenttopredicttidalcurrentspeeds,andultimatelytidalkineticenergyandpower,providesreasonable,butatbestapproximateandasyetunsubstantiated,estimatesofcurrentspeedontheshelf.However,itproducessomewhatlessadequateresultsinareassuchaselongatedcoastalbaysandinnarrowseawaysbetweenislandsandbetweenislandsandthemainland.ThepredictionsfortidalkineticenergyandpowerinKingSound,WesternAustralia,forexample,aresmall,yetthisiswherethelargesttidesinAustraliaoccur(figure11.11).
Overall,thetidalenergyresourceassessmentpresentedhereisacceptableasafirst-estimateatthenationalscale.Itindicatestherelativeimportanceofregions,butitcannotbeconsideredaccurateataregionalorlocalscaleanditcannotbereliedupontoanydegreeotherthanontheopenshelf.Thereisaneedtodevelopanew,nationalscalehydrodynamicmodel,basedonthelatestavailablenationalbathymetricgridandverifiedbysatellitealtimetry,oceanographicmoorings,andtidalstreamdata.Regionalscalehydrodynamicmodelssuitableforelongatecoastalbaysandconvolutedcoastlinesneedtobedevelopedfordetailedsiteassessment.
Wave energyThedatausedtoundertakethewaveenergyresourceassessmentarewaveconditionshindcastusingtheWAMModel–athirdgenerationoceanwavepredictionmodel(Hasselmannetal.1988)–implementedbytheAustralianBureauof
Meteorology.ThehindcastwavedatafromtheWAMmodelwereconvertedtowaveenergyandpower(energyflux)usinglinearwavetheoryforarbitrarydepth.DetailsofthemethodsusedarediscussedinfullinHughesandHeap(2010).TheAustralianWAMmodelgridhasaresolutionof0.1degreeandtheresolutionforsignificantwaveheightinthehindcastwavedatais0.1metre.Theaccuracyvarieswithconditions,butisnominally0.25metreforwaveheightsintherangeusedforelectricitygeneration.Theresolutionofthewaveperiodis0.1secondandtheaccuracyisnominally1second.Thisequatestoapercentagerangeofuncertaintyinthecalculatedwaveenergydensityandpowerof100percentormoreforsmallwaveheights(lessthan1metre),butdecreasingrapidlyto17percentorlessforlargerwaveheights(greaterthan6m).Inessence,thepercentageuncertaintyisleastforthesouthernhalfofAustralia’scontinentalshelfwheretheresourceisofmostpromise.
TheresultsofthisassessmentappearbroadlyconsistentwiththoseofastudyofAustralia’swaveenergyresourcebyRPSMetOceanfortheCarnegieCorporation(nowCarnegieWaveEnergyLimited),anextractofwhichwaspublishedintheCorporation’s2008AnnualReport.TheMetOceanwaveenergyresourceassessmentconcludedthat,onthesouthernhalfofAustralia’sshelf,thereisanestimatedresourceof525000MWindeepwaterand171000MWinshallowwater(adepthoflessthan25metres)(CarnegieCorporation2008).TheMetOceanrankingsofeachjurisdiction’sresourcearealsoconsistentwiththerelativemagnitudesofvaluesintables11.5to11.6,butcannotbedirectlycomparedbecausetheirdataarepresentedindifferentunitsofmeasurement.
Overall,thewaveenergyresourceassessmentpresentedhereisconsideredtobesufficientlyreliableasanationalscaleassessment.Itisbestsuitedtowaterdepthsgreaterthan25m.Inwaterdepthslessthan25mtheWAMmodeldoesnotsufficientlyaccountforshallowwaterprocesses(e.g.frictioneffectsandrefraction)thatdissipateorredistributethewaveenergy.Giventhatmanyofthecurrenttechnologiesaredesignedfordeploymentinwaterdepthsof25morless,andsomeontheshoreline,amorerefinedassessmentiswarranted.Thiswouldinvolve:
1. usingthespatiallylimitedwaveriderbuoydatatoverify/calibratetheWAMModeldata,providingamoreaccuratedatasetwithcompletecoverage oftheshelf.
2. Integratinggeographicinformationlayerssuchasbathymetry,seabedtype(gravel,sand,mud,reef),andcoastalgeomorphologyintoaGIStogetherwiththewaveclimatologytoidentifytheaccessibleresource.Thisintegratedapproach willhaveastronginfluenceondeterminingwhetherasiteissuitableforawavefarm,irrespectiveofthewaveclimate.
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densitiesofmorethan2.5kJ/m2,withlargeareasoftheshelfexperiencingtwicethisvalue(e.g.westernandsouthernTasmania).MuchofthesouthernAustraliancoastlineexperiencessignificantwaveheights(inexcessof1m)virtuallyallofthetime.
ThetotalwaveenergyontheentireAustraliancontinentalshelfatanyonetime,onaverage, isabout3.47PJ.Thetotalamountofwaveenergy ontheshelfadjacenttoeachstateislistedin
table11.5.Thewaveenergyadjacenttoeachjurisdictionatanyonetimereflectsboththearea ofshelfwatersandtheenergydensityinthosewaters.Forexample,VictoriaandTasmaniahave, onaverage,aboutthesametotalwaveenergyas theNorthernTerritory;however,itisconcentrated inasmallershelfarea.
TheshelfwatersoffVictoriaandTasmaniaaresuitablesitesforharvestingwaveenergy,whereastheshelf
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130° 140° 150°
Tidal power (W/m2)100
40°
0
Figure 11.9 Spatialdistributionoftime-averagedtide(kinetic)power(W/m2)ontheAustraliancontinentalshelf (notdepthintegrated).The(kinetic)powerateachlocationrepresentsatime-averageoveranyoneyear.Notethat thecolourscalesaturatesat100W/m2toshowdetail;themaximumvaluepresentis6179W/m2
source: GeoscienceAustralia
Table 11.4 Meanandpercentilesoftide(kinetic)power(W/m2)andtotaltidekineticenergydeliveredannually(GJ/m2)onthecontinentalshelfadjacenttoeachstate
Jurisdictionmean
Power (W/m2)
10th percentile 50th percentile 90th percentileEnergy (gJ/m2)
NorthernTerritory 2069.50 18.07 1029.68 5979.38 65.45
Queensland 4153.19 33.97 2316.85 10679.20 131.35
NewSouthWales 0.36 0.024 0.19 0.96 0.0011
VictoriaandTasmania 488.93 6.03 378.06 1193.56 15.46
SouthAustralia 317.16 0.43 78.86 1014.65 10.03
WesternAustralia 6179.39 249.42 7529.65 10679.20 195.43
source: GeoscienceAustralia
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watersofftheNorthernTerritoryarenotsuitable, atleastwithexistingtechnology.Considerationmustalsobegiven,however,totherateatwhichusefulenergycanbedelivered.Inthecaseoftidalandwaveenergyresources,thelackofcontroloverthetiming,rateorlevelofdeliverycanimpactsignificantlyontheirpotentialasanelectricitysource.
Table 11.5 Totalwaveenergy(onaverageatanyonetime)onthecontinentalshelfadjacenttoeachstate
Jurisdiction Total energy (TJ)
NorthernTerritory 458.20
Queensland 805.04
NewSouthWales 69.53
VictoriaandTasmania 485.49
SouthAustralia 631.62
WesternAustralia 1018.10
National Total 3467.98
Note: Thesedatawereobtainedbytakingthetime-averageofthe11-yeartimeseriesofwaveenergydensityavailableateachgridpoint,multiplyingbytheareaofa0.1by0.1degreequadrantateachgridpoint,andsummingtheresultsforallgridpointsacrosstheshelf source:GeoscienceAustralia
Therateofdeliveryofwaveenergy,orenergyflux,
isalsoreferredtoaswavepower.Thespatial
distributionoftime-averagedwavepoweronthe
Australiancontinentalshelfisshowninfigure11.12.
Wavepowerisalsogreatestonthesouthernhalf
oftheAustralianshelf,with25–35kW/mbeing
commonontheoutershelf.Despitethefactthat
thereisaconsiderableamountofenergyonthe
northernhalfoftheAustralianshelfatanyonetime
duetothelargeshelfarea(table11.6),theenergy
densityandpowerorratethattheenergyisdelivered
issmall(figures11.11and11.12).Forexample,
wavepowerofftheNorthernTerritoryshelfistypically
lessthan10kW/mandunsuitableforharvesting
withcurrenttechnologies.
Thespatialdistributionoftotalannualwaveenergy
(thetotalwaveenergydeliveredinayear)isshown
infigure11.13.Thisannualresource(expressedin
joulespermetre),isthetheoreticaltotalannualwave
energyavailablealongalineorthogonaltothewave
direction.Inpractice,theresultdependsonwhere
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20°
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130° 140° 150°
40°
Tidal energy (GJ/m2)2
Work in progress
Transmission linesExisting and proposed tidal project
0
Figure 11.10 SpatialdistributionoftotalannualtidekineticenergyontheAustraliancontinentalshelf(lessthan 300mwaterdepth),withexistingandproposedprojects
Note: Thekineticenergyateachlocationrepresentsthetotaldeliveredinayear.Dataobtainedfromalinearised,shallowtidemodel. Thecolourscalesaturatesat2GJ/m2toshowdetail;themaximumvaluepresentis195GJ/m2
source: GeoscienceAustralia
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thelineisdrawn.Generally,thefurtheroffshorethelineisdrawnthegreaterthetotalenergyresourceavailable,becausewavesloseenergyandpowerastheyapproachthecoast.
Theenergyandpoweravailableforwaterdepthslessthanorequalto50m(atwhichcurrentgenerationenergyconverterspredominate)arelistedintable11.6.Boththepowerandthetotalannualenergyavailableinthelessthanorequalto50mdepthrangearegenerallyslightlysmallerthanthetotalenergyandpoweravailableindeeperwater.The
differencesbetweenthetwoaremorepronouncedinNewSouthWales,VictoriaandTasmania.
Onthebasisoftheassessmentsummarisedintable11.6,thestateswiththebestwaveenergyresourceareWesternAustralia,SouthAustralia,VictoriaandTasmania.Tasmaniaisparticularlywellendowedwithwaveenergyresources.Therearelocationsoffitscoastwheretheaveragewavepowerinwaterdepthslessthanorequalto50mreachalmost35kW/m,deliveringatotalwaveenergyof1100GJ/mannually.
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0 750 km
10°
20°
30°
130° 140°
40°
150°120°
Wave energy density (kJ/m2)7
0
Figure 11.11 Spatialdistributionoftime-averagedwaveenergydensityontheAustraliancontinentalshelf,inkJ/m2. Theenergydensityateachlocationrepresentstheaverageoftheavailable11-yeartimeseriesfromMarch1997toFebruary2008
source: GeoscienceAustralia
Table 11.6 Meanandpercentilesofwavepower(kW/m)andtotalenergy(GJ/m)deliveredannuallyinwaterdepthsequaltoorlessthen50m
Jurisdiction Power Energy
mean 10th percentile 50th percentile 90th percentile mean
NorthernTerritory 5.32 0.33 2.68 13.09 167.90
Queensland 14.72 3.52 9.03 29.82 442.80
NewSouthWales 13.61 2.77 7.31 27.19 391.04
VictoriaandTasmania 34.87 4.88 18.22 70.66 1100.80
SouthAustralia 25.51 4.28 15.35 54.96 885.13
WesternAustralia 26.38 4.65 15.05 56.86 901.44
source: GeoscienceAustralia
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11.3.2OceanenergymarketInAustralia,fourelectricitygenerationunitsbasedoneithertidalorwaveenergyhavebeendevelopedinrecentyears(table11.7).Allfourunitsarepilotordemonstrationplantswithcapacitiesoflessthan0.5MW.Thesefourprojectshavecollectivelyaddedlessthan1MWofgeneratingcapacity,buttheyrepresentanimportantstageinthetechnologyinnovationprocessforoceanenergyinAustralia.
CarnegieWaveEnergyLimited(formerlyCarnegie
Corporation)holdstheintellectualpropertyand
globaldevelopmentrightsfortheCylindricalEnergy
TransformationOscillator(CETO)waveenergy
converter(seeBox11.2foratechnologydescription).
CarnegiecompletedtheCETO2pilottest(proofof
concept)atFremantleandinlate2009announced
plansforademonstrationproject(box11.3).
Oceanlinxhashada500kWprototypeoscillating
watercolumnwavepowerunit(box11.2)atPort
Kembla,NewSouthWalessince2006.Thisunit
iscurrentlybeingreplacedbyathirdgeneration
demonstrationscaledevicedesignedtosuitthe
environmentatPortKemblaandisduetobecommissionedinearly2010.Oceanlinxisalsodevelopingalargescaledemonstrationproject(upto2.5MWperwaveenergyconverter)atPortland,Victoria(www.oceanlinx.com).
Themostrecentoceanenergyprojectbasedontidalenergybeganoperationsin2008.The150kWtidalplantwasinstalledbyAtlantisResourcesCorporationatPhillipIsland(southofMelbourne)(www.atlantisresourcescorporation.com).
11.4Outlookto2030forAustralia’soceanenergyresources and marketOceanenergyresourceshavesignificantpotentialforfutureutilisationbutareatanearlystageofdevelopmentandhaveyettobedemonstratedtobeacommerciallyviableoptionforelectricitygenerationinAustralia.However,giventhelevelofglobalRD&Dactivity,itispossiblethattechnologicalandeconomicadvanceswillincreasethecommercialattractivenessofoceanenergy.
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0 750 km
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20°
30°
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40°
150°120°
Mean wave power (kW/m)50
0
Figure 11.12 Spatialdistributionoftime-averagedwavepowerontheAustraliancontinentalshelf(kW/m). Thewavepowerateachlocationrepresentsatime-averageoftheavailable11-yeartimeseriesfromMarch 1997toFebruary2008
source: GeoscienceAustralia
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11.4.1KeyfactorsinfluencingthefuturedevelopmentofAustralia’soceanresourcesAustraliahasasignificantpotentialoceanenergyresource,especiallyalongitswestern,northernandsoutherncoastlinesifbothwavesandtidesareconsidered.GovernmentpoliciessuchastheexpandedRenewableEnergyTarget(RET)andtheproposedemissionsreductiontargetcouldcontributetoamorefavourableenvironmentforoceanenergyresourcedevelopment.Therehasalsobeendirectgovernmentfundingforoceanenergy:VictorianWavePartnersobtaineda$66milliongrantfromtheAustralianGovernmenttowardsthecostofa19MWcommercial-scalewavepowerdemonstration
projectatPortland.ThegrantwasfundedfromtheRenewableEnergyDemonstrationProgram.
Despiteitspotential,therearesignificantconstraintsonthefuturedevelopmentofoceanenergyinAustralia.Twolimitationsinparticularneedtobeaddressed:technologiesforthecommercialconversionandutilisationofoceanenergyarestillimmature;andcapitalcosts,includinggridconnection,arehighrelativetootherenergysources.Anumberoftechnologieshavepassedproof-of-conceptstagebutmanyareyettodeliverelectricitytoagrid.Someofthemhavereachedthecommercialscaledemonstrationstageandmaybeincommercialoperationbymid-thisdecade,buttheywillstillbein
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20°
30°
130° 140°
40°
Transmission linesExisting and proposedwave energy projects
150°120°
Wave energy (TJ/m)1.5
0
Figure 11.13 Totalannualwaveenergy(TJ/m)ontheAustraliancontinentalshelf(waterdepthslessthan300mandwaveenergyprojects.Thetotalannualwaveenergyateachlocationrepresentsanaverageofthe11years fromMarch1997toFebruary2008
source: GeoscienceAustralia
)
Table 11.7 OceanenergypilotanddemonstrationplantsinAustralia
Project Company state start up Capacity
Portland(waveenergy) OceanPowerTechnologiesandPowercorAust
VIC 2002 0.02MW
Fremantle(waveenergy) CarnegieWavePowerLtd WA 2005 0.1MW
PortKembla(waveenergy) Oceanlinx NSW 2006 0.5MW
SanRemo(tidalenergy) AtlantisResourceCorporation VIC 2008 0.15MW
source: GeoscienceAustralia
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competitionwithother–insomecasesmorematureandlowercost–renewableenergytechnologies.
Ocean energy provides a low emissions source of energy with potential for base load electricity generation Oceanenergyisarelativelypredictable,andthereforeapotentiallyattractivesourceofelectricity,generatedwithlowgreenhousegasemissions.Thereliabilityofsomeformsofoceanenergysuchasoceanthermalmaymakeitpotentiallysuitableforbaseloadelectricitygeneration.Otherformsofoceanenergy,suchastidalenergy,whilenotconsistentinprovidingenergy,canbeaccuratelypredicted,andtherefore,shouldfacilitategridintegration:
• Tidal energyisverypredictable,butcannotbeusedtogenerateelectricityatconsistentlevelsconstantly.Twiceinevery12.42hours(24hoursinsomelocations)thetidalcurrentspeedandhencetheelectricitygenerationcapabilityfallstozero.Iftidalenergyisrequiredtoproduceasustainedbaseloadforthelocalgrid,someformofenergystorageorback-upwillbeneeded.
• Wavesarerarelyofconsistentlengthorstrength.Waveenergylevelsmayvaryconsiderablyfromwavetowave,fromdaytoday,andfromseasontoseason,becauseofvariationsinlocalanddistantwindconditions.Thisinherentvariabilityneedstobeconvertedtoasmoothelectricaloutputtobeareliablesourceofelectricitysupply.Moreover,therearesitesonthewesternandsoutherncoastlineswhereregularstormsintheSouthernOceangenerateconsistentswellswithperiodsofwaveenergyfailurebothoflowfrequencyandshortduration.Higherlevelforecasting,gridmanagementorpossiblyenergystoragesystemsareneededtosmoothoutsuchpeaksandtroughsinsupply.
• Ocean thermal energyispotentiallysuitableforbaseloadelectricitygeneration,astheoceantemperaturesonwhichitreliesshowonlyslightvariationbetweenseasons(WEC2007).
RD&D activity is critical for the future development of ocean energy resourcesDespitethelargepotentialoceanenergyresource,thelowlevelofmarketuptakecanbelargelyattributedtothecurrentlyimmatureextractiontechnologyandthelargenumberofdifferenttechnologiesbeingtrialled.Tidalcurrentsystems areconvergingonafewdifferentconverterdesigns;forotherformsofoceanenergy,therehassofarbeennosuchconvergence:
• Tidal energy technologies–tidalenergyextractiontechnologyisessentiallyanalogoustothatofwindenergy.Bothrequireapassingcurrenttodrivearotatingturbine.Tidal
energyturbinesaresubjecttolessturbulentenvironmentsthanwaveenergy.
• Wave energy technologies–Manydifferentwaveenergyconvertersareattheprototypestageandareundergoingtrialsinanumberofcountries.Thisispartlyexplainedbytheneedtodeveloptechnologiesforarangeofdifferentwaveenergyenvironmentsandclimaticconditions,includingtheabilitytosurvivesignificantstorms,andbythelackofindividualtechnologiesthathavebeenshowntobecommerciallyviable.
• Ocean thermal energy technologies –oceanthermalenergyconversiontechnologiesarerelativelynewandstillneedtobeproveninpilotscaleanddemonstrationscaleplants.Land-based,floatingandgrazingplantsarealloptions.OTECisbestsuitedtotropicalwaterswithwarmsurfacewaters.
Currently,25countriesareparticipatinginthedevelopmentofoceanpower,withtheUnitedKingdomleadingthedevelopmenteffort,followedbytheUnitedStates,Canada,Norway,AustraliaandDenmark.InPortugalthreePelamiswaveenergyconverterswithacombinedcapacityof2.25MWhavebeentrialled,butarecurrentlynotinuse.
Althoughthereispotentialenergyfromother oceansources,currentoceanpowerdevelopmenteffortshavefocussedontidalandwaveenergy (IEA2009c).
Tidal energyAtleastninecountriesoutsideAustraliahaveademonstratedinterestintidalenergyforcommercialelectricitygeneration(table11.8).AllofthesecountriesprovidesupportforR&Dinuniversitiesand/orgovernment-fundedresearchinstitutes;theR&Dcommitmentextendstothecommercialsectorineightofthecountries.Therearefull-scaleplantscurrentlyoperatinginthreecountries.Inaddition,in2009a1MWtidalplantwascommissionedintheRepublicofKoreaandthe260MWtidalplantutilisinganexistingseawallattheentrancetoLakeSihwaisunderconstruction.Theprojectwillcreateenvironmentalflowsforthelake.AmajortidaldevelopmentprojecthasalsobeenadvancedfortheSevernRiverintheUnitedKingdom,basedonaseriesofthreeproposedbarragesandtwolagoons.
Wave energyAsignificantnumber(atleast20)ofcountries,includingAustralia,havedemonstratedaninterestinwaveenergyforcommercialelectricitygeneration(table11.9).AllbutSpainareinvolvedinR&Dinuniversitiesand/orgovernment-fundedresearchinstitutes;theR&Dcommitmentextendstothecommercialsectorin14ofthecountries.
CHAPTER 11: OCEAN ENERGY
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Currentlyoperatingfull-scaleprojects,albeitatthedemonstrationstage,existin10countriesoutsideAustralia.Thesizeofthesecurrentprojectsrangefromsmallplantsofhundredsofkilowattsinsize,tothelargestbeingthe2.25MWAguçadouraWaveParknearPóvoadeVarziminPortugal.Thisproject,anditsproposedexpansionto21MW,havebeensuspendedpendingresolutionoftechnicalissuesandobtainingnewfinancing.A4MWwavefarmisplannedforSiadarontheIsleofLewisinScotland.
Amoresubstantialproject,theSouth-westRegionDevelopmentAuthority’sWaveHubinCornwall,iswelladvancedinorganisationofa20MWwaveenergyarray,involvinganumberoftechnologysupplierseachinstalling4–5MWsystems.OPT,whichasamemberofVictorianEnergyPartners,isdevelopingademonstrationprojectatPortlandwiththeAustralianGovernment’sassistance,isthefirsttechnologysupplierengagedtoinstallgeneratorsattheCornwallWaveHub.
Ocean thermal energyAnimportantfocusinRD&Dactivity,particularlyinEurope,isthecombinationofOTECtechnologieswithotherdeepwaterapplications,suchaspotablewaterproduction,thatresultinbenefitsinadditiontoelectricitygeneration(WEC2007).ThreemajorstudiesinEurope(EuropeanCommission,MaritimeIndustriesForumandUKForesight)haveresultedinrecommendationsforbothOTECandotherdeepwaterenergyapplicationsthatemphasisedfundingandconstructionofaplantinthe5–10MWrange.
Ademonstrationplantwithacapacityof1–1.2MWplannedforconstructioninHawaiiisawaitinggovernmentapprovalfollowingcompletionofanenvironmentalimpactassessment.Plansfor10and25MWoceanthermalenergyprojectsarebeingconsidered(WEC2008).
R&DonOTECandotheroceanenergytechnologieshasbeenundertakensince1974byanumberoforganisationsinJapan.SagaUniversityconductedthefirstOTECelectricitygenerationexperimentsinlate1979andmorerecentlyhasbeencollaboratingwiththeNationalInstituteofOceanTechnologyofIndiaona1MWplantofftheIndiancoast(WEC2008).
Ocean energy technologies are expected to be relatively high cost options until technologies matureGiventhelargelypre-commercialstatusofthecurrentoceanenergyindustries,theoutlookishighlydependentontheamountofresourcesdevotedtoRD&D,andthepotentialforcostreductionovertime.ThisincludesRD&Dactivitybothinsurveyingtechniquestoassessenergypotentialandenergyconversiontechnologies.
Table 11.8 CountryinvolvementintidalenergyR&Dand/orwithfullscaleplant
Country govt and academic
R&D
Commercial R&D
Currently Operating Projects
Canada ✓ ✓ ✓
China ✓ ✓ ✓
France ✓ ✓ ✓
India ✓
Republic ofKorea
✓ ✓ Underconstruction
Norway ✓ ✓
RussianFederation
✓ ✓
UnitedKingdom
✓ ✓
UnitedStatesofAmerica
✓ ✓
Note: Tablemaynotincludeallprojects,especiallysmallerR&Dprojects,butincludesthemaincountriesinvolved source:IEA2009c
Table 11.9 Countryinvolvement(otherthanAustralia)inwaveenergyR&Dand/orwithfull-scaleprojects
Country govt and academic
R&D
Commercial R&D
Currently Operating Projects
Canada ✓ ✓
China ✓ ✓ ✓
Denmark ✓ ✓ ✓
Finland ✓ ✓
France ✓
Germany ✓
Greece ✓ ✓
India ✓ ✓
Ireland ✓ ✓ ✓
Japan ✓ ✓ ✓
Mexico ✓
Netherlands ✓ ✓
NewZealand ✓ ✓ ✓
Norway ✓ ✓ ✓
Portugal ✓ ✓ ✓
Spain ✓
SriLanka ✓
Sweden ✓
UnitedKingdom
✓ ✓ ✓
UnitedStatesofAmerica
✓ ✓ ✓
source: IEA2009c
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Investmentcostsarecurrentlylowerfortidalbarrage
systemsthanfortidalcurrentorwavesystems.
Investmentcostsfortidalbarragesystemsare
estimatedtohavebeenUS$2–4millionperMW
in2005,whileinvestmentcostsfortidalcurrent
andwavesystemsareestimatedtohavebeen
US$7–10millionperMWandUS$6–15millionper
MW,respectively(IEA2008).Shorelineinstallations
andtidalbarragesystemstypicallyhavealower
productioncostthandeepwaterdevices,butmost
deepwatertechnologiesarestillattheR&Dstage.
However,waveenergytechnologiestendtohave
highercostsbecauseofunscheduledmaintenance
causedbystormdamage.
Oceanenergytechnologiesareexpectedtoremain
relativelyhighcostoptionsfordevelopmentinthe
mediumterm.
Investmentandproductioncostsforoceanenergy
systemsareprojectedtofallovertime.Theyare
projectedtofallmoresignificantlyforwaveenergy
systemsthanfortidalbarragesystemsaswave
technologiesarecurrentlylessmature.Tidalbarrage
systemscurrentlyhavethelowestproductioncost
ofalloceanenergytechnologies.Tidalbarrage
productioncostswereestimatedtohaveranged
fromUS$60toUS$100perkWin2005,whilethe
productioncostoftidalcurrentsystemsisestimated
tohavebeenUS$150–200andtheproductioncost
ofwaveenergysystemstohavebeenUS$200–300
(IEA2008).Astherelativelynewerwaveandtidal
currenttechnologiesmature,thedifferencebetween
theproductioncostsofthesetechnologiesandtidal
barragesystemsisprojectedtofall.By2030,the
productioncostsofoceanenergytechnologiesare
projectedtorangefromUS$45toUS$100perkW
(in2005dollars)(figure11.14).
0
50
300
250
200
150
100
Tidal barrage Tidal current Wave
2005
US$
/kW
AERA 11.14
2005 2030 2050Year
Figure 11.14 Oceanenergyproductioncostssource: IEA2008
australia’s population is mainly located in coastal areas, but grid access may be a significant issue for more remote future ocean energy projects
Tidal energyThebesttidalenergyresourcestendtobelocatedoffthemoreremotecoastlinesalongthenorthernmarginofAustralia.Withthepresenttechnologyconstraints,themostsuitablesitesforharvestingwithgoodaccesstotheelectricitygridfavouronlyafewregionalcentres,althoughtherearelargeresourceswithinreasonableproximitytothemajorcentresofDarwinandMackay.Thedomesticdemandforelectricityisrelativelysmallintheverywell-resourcedareasoftheKimberleyandPilbara,buttide-generatedelectricitycouldpotentiallycontributetotheenergyrequirementsoftheminingsector.
Theenvironmentalimpactofabarrage-typepowerstationmaynotbeacceptableintheseenvironmentallysensitiveregions.However,thereisthepotentialforconvertersthatharvestkineticenergyfromtidalcurrentswithmuchlowerenvironmentalimpact.The1.2MWtideturbinebeinginstalledatKoolanIsland(WesternAustralia)willmeetupto20percentofthepowerneedsoftheminingoperationstherewhenoperationalin2010(box11.3).Ingeneral,however,theindustrialloadsofremoteminingoperationsarecommonlyservicedbygas-firedgenerators.Newrenewableenergyoptionssuchastidalorwave,intheabsenceofcapitalgrantsorothersubsidiessuchasfeed-intariffs,willneedtocompetewiththeprevailing,long-run,marginalcostofgasgeneration.
Wave energyThebestwaveenergyresourcestendtobelocatedoffthemoreremotecoastlinesalongthesouthernmarginofAustralia.Withthecurrenttechnologyconstraints,themostsuitablesitesforharvestingwithaccesstotheelectricitygridfavouronlyafewregionalcentres.Thismaychangeintimeifthecurrentsmall-scaleprojectsof0.5MWto1MWevolveintosignificantprojectsof100MWormore,andthepossibilityofconnectingoverlongerdistancestothegrid–orexpandingthegrid–totakeadvantageofthisresourceisdemonstratedtobeeconomic.
Ocean energy is a zero or low emissions renewable resource, but other environmental impacts also need to be assessedElectricitygenerationfromwaveortidalenergyproducesnogreenhousegasemissions;however,emissionsassociatedwiththeproductionofthewaveortideenergydeviceandotherenvironmentalissuesmustalsobetakenintoaccount.
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Tidalbarragesdisruptthesurroundingenvironmentmorethanothertidalorwaveenergysystems.Tidalbarragesreducetherangeoftidesthatoccurinsidethebarrage.Thismayhavenegativeimpactsonwaterqualityandbiodiversityinthesurroundingareaandcauselossofhabitatwhereintertidalzonesarereducedinarea(IEA2008).Offshoretidalorwaveenergyprojectstypicallyhavealowerimpactontheenvironment.However,offshoresystemsmayposeanavigationhazard,andthereforemustbelocatedinareasthatarenotheavilynavigated.Theremayalsobepotentialconflictswithotherlocalusesofthemarineareaandapossibleimpactonmigratingmarinemammals.Theextentofthepotentialimpactswilldependonthetypeofwaveenergyconvertertechnology;underseatechnologiestendtohave lessimpacts.
Waveandtidalenergysystemslocatedneartheshorelinemaybeobjectedtobynearbycommunitiesonthegroundsofnoiseandpossiblyvisualpollution.Thismayresultinpublicoppositiontoprojects,particularlyiftheyarelocatedinpopulatedareas.
11.4.2OutlookforoceanenergyresourcesWaveandtidalenergyarenon-depletableresources;increaseduseoftheresourcesdoesnotaffectresourceavailability.However,estimatesofresourceavailabilitymaychangeovertimeasnewmeasurementmethodsbecomeavailable.Inaddition,thequantityoftheresourcethatcanbeutilisedwillchangeovertimeasnewtechnologydevelopmentsallowincreasedexploitationofoceanresources.
ThetidalenergyresourceassessmentpresentedinSection11.3.1suggeststhatthereisfuturedevelopmentpotential,largelyonthenorthernhalfofAustralia’scontinentalshelfandparticularly
inKingSoundandtheBonaparteGulf(WesternAustralia),Darwin(NorthernTerritory),theTorresStraitandsouthernpartsoftheGreatBarrierReef(Queensland).Thequalityoftheresourceisspatiallyvariable,butalsohighlypredictableoncefieldmeasurementsofoneyear’sdurationhavebeenobtainedforasite.Thesuitabilityofsiteswillalsobeinfluencedbywaterdepthandseabedtype,whichaffecttheengineeringoftideenergyconvertersandplacementofcablesacrosstheseabed.
ThewaveenergyresourceassessmentdiscussedinSection11.3.1suggeststhatthereisfuturedevelopmentpotentialacrossthesouthernhalfofAustralia’scontinentalshelffromExmoutharoundtoBrisbane.Thequalityoftheresourceisvariable,withthefailurerateofthewavestodeliversufficientenergyandthefrequencyoffailuresgenerallyincreasinginthemorenortherlywaters.Theremayalsobestronglocalvariabilityinboththeresourceanditsaccessibility;thelatterbeingdeterminedbyrequirementsforparticularwaterdepthsandseabedtypesforinstallationofthewaveenergyconvertersandnetworksofpipeorcableacrosstheseabed.
11.4.3OutlookforoceanenergymarketThemajoroceanenergydevelopmentsoccurringinAustraliaarefocussedonprovinguptechnologiesfortidalorwaveenergy.Severalcompanieshaveplansforpilotanddemonstrationplants(box11.3).Importantlyforthefutureoftheoceanenergyindustry,companiesarenowinvestingincommercialscalepowerprojects.Thisisanessentialstepindemonstratingthetechnicalandeconomicviabilityofthesetechnologies.EarlydemonstrationofthecommercialviabilityoftheseorcomparabletechnologiescouldwellacceleratethedevelopmentofwaveandtideenergyinAustralia.
BOx 11.2 CURRENTOCEANENERGyTECHNOLOGIES
Tidal energy technologiesTherotatingtidewavesresultindifferentsealevelsfromoneplaceontheshelftothenextatanyonetime,andthiscausesthewatercolumntoflowhorizontallybackandforth(tidalcurrents)overtheshelfwiththetidaloscillationsinsealevel.Twodifferenttechnologieshavebeendevelopedtoharnessthesetidalmovements.
Thedesignofunderwaterturbineshasadvancedconsiderablyinrecentyears,butthereisstillconsiderableresearchanddevelopmentseekingtomaximiseefficiencyandrobustnesswhileminimisingoverallsize(figure11.15).
Barragesharnesssomeofthepotentialenergyofthetide.Inessence,abarragewithsluicegatesallowswatertoenterthebasinontherisingtide,andat
hightidethesluicegatesareclosed,thustrappinga
largebodyofwater(figure11.15).Asthewaterlevel
ontheoceansideofthebarragefallswiththeebbing
tide,theelevatedwaterfrombehindthebarrageis
releasedthroughthesluicegates,whereturbines
arelocated,togenerateelectricity.Theprincipleis
similartohydro-electricschemesondammedrivers.
Morecomplicatedsystemsofbasinsandbarrages
canbedesignedtogenerateelectricityonboththe
ebbingandfloodingtide.Thepotentialenergythatis
availabletobeharnessedisrelatedtothevertical
tiderangeandthehorizontalareaofthebasin
(thetidalprism).
Tidalstreamgeneratorsfocusonthekinetic
energycomponentofthetide.Aturbineisplaced
withinatidalcurrentandthekineticenergy
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associatedwiththehorizontalmotionofthe waterdrivestheturbinetogenerateelectricity. Thereareturbinesdevelopedforrelativelyshallowwaterinstallationthatrotateinaverticalplane, andothersthatrotateinahorizontalplane.
Thefirst(andstillthelargest)tidalpowerstationwasbuiltontheRanceRiverestuaryinFrance,between1961and1966.Ithasbeenoperatingcontinuouslysincethen.Itisabarrage-typesystemconsistingofan800-metrelongdamenclosingabasinwithasurfaceareaof22.5km2.Thespringtiderangeisupto13m.Theplanthasapowergeneratingcapacityof240MWanditdelivers2.3PJofenergyannuallytothegrid(WorldEnergyCouncil2007).Asmallerbarrage-typestationatAnnapolis,ontheBayofFundy,Canadawascompletedin1984.Thetiderangeinthislocationcanexceed12m(Pugh2004).Thisplanthasapowercapacityof20MWanddelivers108TJannually.TheRepublicofKoreaiscurrentlybuildingthelargestbarrage-typepowerstation(260MW)atSihwaLakewithcompletionduethisyear.Chinahassevensmallbarrage-typepowerstationswithatotalcapacityof11MW,andplansformore.Indiaalsohasplansforabarrage-typepowerstation(WorldEnergyCouncil2007).
Powerstationsseekingtoharnessthekineticenergyoftidalcurrentsarepresentlymuchsmaller,andstillinthedevelopmentalphase.NorwayhasthefirstgridconnectedunderwaterturbinelocatedatKvalsundet,whichhasa300kWpowercapacity(WorldEnergyCouncil2007).TherearesimilarpilotprojectsintheRussianFederation,theUnitedKingdomandtheUnitedStates.
Wave energy technologiesTooperateefficientlyawaveenergyconvertermustbetunedforthemodalwaveenergyconditions,butalsodesignedandengineeredtowithstandextremeenergyconditions.Thisposesasignificantchallenge,
becauseitisthelowerenergylevelsthatproducethenormaloutput,butthecapitalcostisdrivenbythedesignstandardnecessarytowithstandextremewaves(WEC2007).Thereisalargenumberofdesignsforwaveenergyconverters.Forthemostpart,theycanbebroadlygroupedintooneoffourtypes(table11.10).
Oscillating water columns(OWCs)consistofasemi-enclosedairchamberthatispartiallysubmerged(figure11.16).Thepassageofwavespastthechambercausesthewaterlevelinsidethechambertoriseandfall,andtheoscillatingairpressuredrivesairthroughaturbinetogenerateelectricity.OWCshavebeendevelopedforinstallationontheshoreline,inshallowwaterrestingontheseabed,andindeepwatermountedonasurfacebuoy.
Hinged (and similar) devicesaresubmergedunitsthatconsistofapaddleorbuoythatoscillateswiththepassageofwaves(figure11.16).BoththeOysterandCETOusethismotiontopumphighpressurewaterashore.Theintentionisforthiswatertobepushedthroughturbineslocatedonshoreforelectricitygeneration.Thewatercanalsoundergoreverseosmosistoproducepotablewater.Theseexampleshavepassedproofofconcept,deliveringhighpressureseawaterashore.However,theseareyettodeliverelectricitytothegrid.
Overtopping devicesaredesignedtocauseoceanwavestopushwateruptoareservoirsituatedabovesealevel,fromwhichthewaterdrainsbacktosealevelthroughseveralturbines(figure11.16).Thesedeviceshavebeendesignedforbothshorelineandoffshoreinstallation.
Oftheremainingtypes,the Pelamis wave energy converterconsistsoftwoormorecylindricalsectionslinkedtogether(figure11.16).Thepassageofwavescausesthesectionstoundulate,andthemovementatthehingedjointsisresistedbyhydrauliccylinders
Table 11.10 Examplesofdifferenttypesofwaveenergyconverters
Device Example Location of Location of Proof of Electricity installation generator concept to grid
LIMPET Shoreline Onshore ✓ ✓Oscillatingwatercolumns
EnergetechOWC Seabed,shallowwater Offshore ✓ ✓
OPTPowerBuoy Seabed,shallowwater Offshore ✓
Hinged(andsimilar) Oyster Seabed,shallowwater Onshore ✓ ✓
devices CETO Seabed,shallowwater Onshore ✓
WaveDragon Surface,tetheredto Offshore ✓ ✓
OvertoppingdevicesSeawaveslotcone
seabed
Shorelineoroffshore Onshoreor ✓
offshore
Pelamis Surface,tetheredto Offshore ✓ ✓
Other seabed
Archimedesswing Immediate Offshore ✓
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CHAPTER 11: OCEAN ENERGY
thatpumphighpressurefluidthroughhydraulicmotorsandelectricalgenerators.Thearchimedes Waveswingconsistsofasub-surfacevertical cylindertetheredtotheseabed(figure11.16). Anair-filleduppercylindermovesagainstalowerfixedcylinderwiththepassageofeachwave.Theverticaloscillatorymotionisconvertedtoelectricitywithalineargenerator.
Ocean thermal energy conversion (OTEC) technologiesTherearethreetypesofelectricityconversionsystemsforoceanthermalenergy:closedcyclesystems,opencyclesystemsandhybridsystems.
• Closed-cycle systemsusetheocean’swarm
surfacewatertovaporiseaworkingfluidwitha
lowboilingpoint,suchasammonia.Thisvapour
expandsandturnsaturbinewhichactivatesa
generatortoproduceelectricity.
• Open-cycle systemsboiltheseawaterby
operatingatlowpressures,producingsteam
thatpassesthroughaturbinetogenerate
electricity.
• Hybrid systemscombinebothclosed-cycleand
open-cyclesystems.
Ocean
Estuary
Estuary
Ocean
Tide going in
Turbine andgenerator
Tide going out
AERA 11.15b
a b
c d
e f
Figure 11.15 Examplesofdifferenttypesoftidalenergyconverters.(a)LaRanceRiverestuarytidalbarrage (b) Schematicshowingthewaterlevelseithersideofabarrageduringpowergeneration(c)SeaGenerationLtd’sSeaGenturbinewithbladeselevatedforservicing(d)BioPowerSystem’sbioStreamturbine(e) and (f)AtlantisResourcesCorporation’sNereusandSolonturbines,respectively
source: WikimediaCommons;www.seageneration.co.uk;www.biopowersystems.com;AtlantisResourcesCorporation
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306 Overtopping
Reservoir
Turbine outlet
Reservoir
AERA 11.16f
OFF-THE-SHELF TECHNOLOGY
LOW PRESSURE SEAWATER RETURN PELTON TURBINE
WITH ELECTRICAL GENERATOR
20-50 METRES HIGH PRESSURE WATER DEPTH SEAWATER
POWER TO THE USER
CETO TECHNOLOGY
ZERO EMISSION DESALINATED WATER
ZERO EMISSION ELECTRICITY INTO GRID
a b
c d
e f
g
h
COPYRIGHT © / NOT TO SCALE
Figure 11.16 Examplesofdifferenttypesofwaveenergyconverters.(a)SchematicofOceanlinxMK3PC(oscillatingwatercolumn)plannedforinstallationatPortKembla(b)OceanPowerTechnologies’PowerBuoy®,AtlanticCity, NewJersey(c)CETOwaveenergyconverter(d)SchematicofCETOwavefarm(e)WaveDragonovertoppingdevice(f)SchematicshowingtheoperationofWaveDragon(g)Pelamiswaveenergyconverter(h)SchematicofArchimedeswaveswing
source: www.oceanlinx.com;www.oceanpowertechnologies.com;www.carnegiecorp.com.au;www.wavedragon.co.uk;www.pelamiswave.com;OregonStateUniversity
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CHAPTER 11: OCEAN ENERGY
OTECplantsmaybeland-based,floatingorgrazing
(WEC2007):
• Land-based plantshavetheadvantageofnotransmissioncabletoshoreandnomooring
costs,butrequireacoldwaterpipetocrossthe
surfzoneandfollowtheseabedtotherequired
depth.Thisresultsinlowerefficiencybecausea
longerpipehasgreaterfrictionlossesandthere
isgreaterwarmingofthecoldwaterbeforeit
reachestheheatexchanger.
• Floating plantsrequireatransmissioncabletoshoreandmooringsindeepwater,buthavethe
advantagethatthecoldwaterpipeisshorter.
TechnologydevelopmentsinhighvoltageDC
transmissionandmooringintheoffshoreoiland
gasindustrymaybeutilisedinfloatingplants.
• grazing plantsareabletodriftinoceanareasthatareprospectiveforoceanthermalenergywhere
theoutput,liquidhydrogen,wouldbeoffloadedinto
shuttletankersfortransporttomarket.
BOx 11.3 PROPOSEDOCEANENERGyDEVELOPMENTPROJECTSINAUSTRALIA
Australiacurrentlyhasnocommercialscaleoceanenergyprojectsatanadvancedstageofdevelopment.
Therearefourcommercialscaleprojectsthatareatalessadvancedstageofdevelopment,threeofwhicharebasedonutilisingtidalenergy(table11.11).TheseprojectsaresignificantlylargerthanthosepreviouslycommissionedinAustralia,withacombinedcapacityof805MW.Twoprojectsaccountforaround93percentofthisadditionalcapacity–theClarenceStraitTidalEnergyproject(450MW)intheNorthernTerritoryandtheBanksStraightTidalEnergyproject(302MW)inTasmania.BothprojectshavebeenproposedbyTenaxEnergyandareexpectedtoenterproductionin2011and2013respectively.
Thereareatpresentnobarrage-typetidalpowerstationsinAustralia.SeveralproposalshavebeenputforwardforastationatDerby,WesternAustralia,includinga2001proposalfora5MWplanttodeliver68.4TJperyear(HydroTasmania2001).Ithasbeensetasidebecauseoftheenvironmentalimpactsofaconstructionof thisscaleonsensitivewetlandsandhighgridconnectioncosts.
AtlantisResourcesCorporationcurrentlyoperatesa150kW(soontobeupgradedto400kW)NereusturbineatatestsiteatSanRemo,Victoria,thatisconnectedtotheelectricitygrid.Thecompanyisinstallinga1.2MWtidalplantnearCockatooandKoolanIslandsinKingSound,northofDerbyinWesternAustraliathatisexpectedtobeoperationalinearly2010.Theprojectinvolvestheinstallationofa16.5metreNereusturbinethatwillprovideupto20percentofthepowerneedsofMtGibsonIron(www.atlantisresourcescorporation.com).
BioPowerSystemshasaproposalforasmallpilotplant(250kW)atFlindersIsland,Tasmania,
tocommencethisyear.Theprojectinvolvestheinstallationofa20metrebioSTREAMturbine.
Thereareseveralcommercialscalewaveenergydemonstrationprojectseitherproposedorunderway,inWesternAustralia,SouthAustralia,VictoriaandTasmania.CarnegieWaveEnergyLimitedannouncedthatithadcompletedafeasibilityassessmentthatidentifiedGardenIslandasthepreferredsiteforthedevelopmentofa5MWdemonstrationwaveenergyprojectbasedonCETO3waveconverter.ThecompanyhasfiveotherprojectsitesinAustraliaatthelicensingagreementstagespreadacrossWesternAustralia,SouthAustraliaandVictoria(Albany,PortMacDonnell,Portland,WarnamboolandPhillipIsland)andisundertakingafeasibilitystudytoassesstheviabilityofusingwaveenergytosupplypowertotheremotenavalbaseatExmouthinWA(www.carnegiecorp.com.au).
VictorianWavePartners,apartnershipbetweenOceanPowerTechnologiesAustralasia(OPTA) andLeightonContractorsPtyLtd,havebeenawardedagrantundertheAustralianGovernment’sRenewableEnergyDemonstrationProgram(REDP)todevelopa19MWwavepowerdemonstrationprojectnearPortlandinVictoria,Australia.TheprojectwilluseOceanPowerTechnologiesInc’sPowerBuoy®waveenergyconverter(box11.2; www.oceanpowertechnologies.com).
BioPowerSystemshasa250kWpilotprojectplannedforKingIsland,Tasmania,incollaborationwithHydroTasmaniausingitsBioWAVEseabed-mountedhingedwaveenergyconverterThepilotisscheduledtobeoperationalin2010,withtheintentionofconnectingittotheisland’selectricitygrid.
OceanlinxisplanningdemonstrationprojecttrialsofitswaveenergyconvertertechnologyinPortland,Victoria.Theprojectwillinvolvetheinstallation
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ofmultipleunitsintegratedintoasinglewavefarm(www.oceanlinx.com).TheVictorianGovernmentisaninvestmentpartnerinthisproject,throughitsCentreforEnergyandGreenhouseTechnologies.Subject
tothesuccessfulcompletionofthedemonstrationphase,thecompanyisconsideringinstallationofawaveenergyconversionarraywithatotalcapacity of30MW.
Table 11.11 CommercialscaletidalenergyprojectsatalessadvancedstageofdevelopmentinAustralia
Project Company Location status start up Capacity Capital Expenditure
Victorian VictorianWave Portland,Vic Govtgrant na 19MW naWavePower PartnersPtyLtd awardedDemonstrationProject
ClarenceStrait TenaxEnergyPty ClarenceStrait, Govtapproval 2011 450MW naTidalEnergy Ltd NT underwayProject
PortPhillipHeads TenaxEnergyPty PortPhillip Govtapproval 2012 34MW naTidalEnergy Ltd Heads,Vic underwayProject
BanksStraitTidal TenaxEnergyPty BanksStrait,TAS Govtapproval 2013 302MW naEnergyFacility Ltd underway
source: ABARE2009
11.5ReferencesABARE(AustralianBureauofAgriculturalandResourceEconomics),2009,ElectricityGenerationMajorDevelopmentProjects–October2009Listing,Canberra,November2009
AustralianHydrographicService,2006,AustralianNationalTideTables,RoyalAustralianNavy,Canberra
CarnegieCorporation,2008,Carnegie2007AnnualReport,CarnegieCorporationLtd
HasselmannKandtheWAMDIGroup,1988,TheWAMModel–Athirdgenerationoceanwavepredictionmodel.JournalofPhysicalOceanography,18,1775–1810
HydroTasmania,2001,StudyofTidalEnergyTechnologiesforDerby.HydroElectricCorporation,ReportNo.WA-107384-CR-01
HughesMGandHeapAD,2010,National-scalewaveenergyresourceassessmentforAustralia.RenewableEnergy(inpress)
IEA(InternationalEnergyAgency),2008,EnergyTechnologyPerspectives2008–Scenarios&Strategiesto2050,Paris
IEA,2009a,WorldEnergyBalances(2009edition),Paris
IEA,2009b,WorldEnergyOutlook2009,Paris
IEA,2009c,OceanEnergy:Globaltechnologydevelopment
status,Paris
Porter-SmithR,HarrisPT,AndersenOB,ColemanR,
GreensladeDandJenkinsCJ,2004,Classificationofthe
Australiancontinentalshelfbasedonpredictedsediment
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WeatherandClimate,CambridgeUniversityPress
WEC(WorldEnergyCouncil),2007,SurveyofEnergy
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