太阳能热利用 热发电 光伏发电 论文

1SolarThermalPowerPlantspreparedfortheEUREC-AgencydraftedversionwithstatusofMay03,2000preparedbyM.Becker*,W.Meinecke*,M.Geyer*,F.Trieb*,M.Blanco**,M.Romero**,Ferrière,A.***1Introduction,PotentialandStrategicSummaryInsolarthermalpowerplantstheincomingradiationistrackedbylargemirrorfieldswhichconcentratetheenergytowardsabsorbers.They,inturn,receivetheconcentratedradiationandtransferitthermallytotheworkingmedium.Theheatedfluidoperatesasinconventionalpowerstationsdirectly(ifsteamorairisusedasmedium)orindirectlythroughaheatexchangingsteamgeneratorontheturbineunitwhichthendrivesthegenerator.Tomakesolarhighflux,withhighenergeticvalueoriginatingfromprocessesoccurringatthesun'ssurfaceatblack-body-equivalenttemperaturesofapproximately5800Kusablefortechnicalprocessesandcommercialapplications,differentconcentratingtechnologieshavebeendevelopedorarecurrentlyunderdevelopmentforvariouscommercialapplications.Suchsolarthermalconcentratingsystemswillundoubtedlyprovidewithinthenextdecadeasignificantcontributiontoefficientandeconomical,renewableandcleanenergysupply.Thispaperdealswiththreedifferenttechnologiesforsolarthermalpowerplantsmakinguseofconcentratingsolarenergysystems(Figure1),namelyby•parabolictroughs,•centralreceivers(towers)and•parabolicdishes.TheWhitePaperoftheEuropeanCommissionforacommunitystrategyandactionplanonrenewableenergiesof1997foreseesatleast1GWeofthosesystemsimplementedinEuropebytheyear2010.Thisobjectivecanbeachievedbyascenarioofanumberof25to30commercialsolarthermalpowerplantswith30to50MWeunitsizeeachanddistributedalongtheSouthofEurope.Thesesolarthermaltechnologiescomplywiththeprimeobjectivesandkeyresearch,technology,anddemonstrationactionsoftheFifthFrameworkProgrammeoftheEuropeanCommission,because•theirdevelopmentswillenhancethedeploymentofsolarenergysystemsforbulkelectricityproductionandtheconservationoffossilenergy,consequentlypreservingtheenvironmentinparticularwithrespecttotheirhighpotentialtocontributetothereductionoftheCO2emissions,•theyreducethegeneratingcostsofsolarpowerplants,andthuscontributetoensuredurableandreliableenergyservicesataffordablecostsinthemedium-tolong-termrange,___________________________*DLR;Köln,StuttgartandAlmería**CIEMAT;MadridandAlmería***CNRS;Odeillo2•theywillprovidetheEuropeanindustrywithaprivilegedtechnologicalposition,thusopeningindustrialgrowthpossibilitiesnotonlytotheinternalmarketofsouthernEuropeancountriesbutalsototheexportofequipmentandservicesinthefieldofsolarplantinstallations;insomerespect,thesolarspecifictechnologyrequiredinmostcasesisalsoaccessibletothelocalindustries;theopportunitytocreatelinkswithdevelopingcountriesandtheirmarketsisself-evident,•theyhavethepotentialtocontributetothesocialobjectivesoftheEuropeanUnionastothequalityoflife,health,safety(includingworkingconditions)andjobcreation;theerectionofsuchplantsatundevelopedareasinsouthernEuropecancreatenewopportunitiesofindustrialfabrication,ofassemblingandofoperationandmaintenance.So,solarthermalpowerplanttechnologiesareimportantcandidatesforprovidingamajorshareofthecleanandrenewableenergyneededinthefuture,because•solarthermalpowerstationsareamongthemostcost-effectiverenewablepowertechnologies;theypromisetobecomecompetitivewithfossil-fuelplantswithinthenextdecade,•solarthermalpowerstationsarealreadytodayofwell-provenanddemonstratedtechnology;since1985nineparabolictrough-typesolarthermalpowerplantsinCaliforniahavefedmorethan8billionkWhofsolar-basedelectricityintotheSouthernCaliforniangrid,demonstratingthesoundnessoftheconcept,•solarthermalpowerstationsarenowreadyformoreintensifiedmarketpenetration;acceleratedgrid-connectedapplicationswillleadtofurtherinnovationandcostreduction.However,nonewcommercialsolarthermalpowerplantshavebeenbuiltsincethelasttwo80MWeparabolictroughplants(SEGSVIIIandIX)wereconnectedtotheSouthernCaliforniagridin1991and1992respectively,duetothefollowingmainreasons:•financialuncertaintiescausedbydelayedrenewaloffavourabletaxprovisionsforsolarsystemsinCalifornia•financialproblemsandsubsequentbankruptcyoftheU.S./IsraeliLUZgroup,thefirstcommercialdeveloperofprivatesolarpowerprojects•rapiddropoffossilenergypricesandfollowingstableenergypricesatlowlevelssinceyearsworld-wide•requiredlargeunitcapacitiesofsolarthermalpowerstationstomeetcompetitiveconditionsforthegenerationofbulkelectricity,resultinginfinancingconstraintsduetotheinherentlylargeshareofcapitalcostsforsolarinstallations•rapidlydecreasingdepreciationtimesofcapitalinvestmentsforpowerplantsduetothederegulationoftheelectricitymarketandtheshifttoprivateinvestorownershipofnewplantprojectsworld-wide•droppingspecificpricesandenhancedefficienciesofinstalledconventionalpowerplantinstallations,particularlyofcombinedcyclepowerplants•missingfavourablefinancialandpoliticalenvironmentsfornewinitiativesforthedevelopmentofsolarthermalpowerplantprojectsinsunbeltcountries.Fortunately,thechancesforsolarthermalprojectsinthenextdecadehaveincreasedinthemeantimesignificantly,because•interestratesandcapitalcostshavefallendrasticallyinEuropewiththeintroductio