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PowerfromcoalwithresponsibilityThetechnologytocaptureandstorecarbonpollutionsafelyandeffectivelyisdevelopingfast.Butwithouteffectivepreparationsnow,vitalopportunitieswillbelost,saysJonGibbins.Theworldfacesanenormouschallengetoproducetheenergyweneedwithoutdamagingthelivesofourchildrenandgrandchildren.Capturingthecarbondioxideproducedfromcombustionoffossilfuelssuchascoal,oilandgasbeforeitgetsintotheatmosphereandplacingitinsteadinsecurestoragedeepundergroundisakeytomeetingourresponsibilities.WelcometotheworldofCarbonCaptureandStorage,orCCS.Carbondioxidecanbecapturedfromalltypesofmodernpowerplants,conventionalsteamboilersandintegratedgasifiercombinedcycleplantsthatareplannedforfutureconstruction.'Post-combustion'systemswashcarbondioxideoutofwastecombustiongasesbeforetheygototheplant'schimneywithacontinuously-recycledsolvent.State-of-the-artdesignsareasignificantimprovementoverthesmallcaptureunitsthathavebeenusedforhalfacenturytoproducecarbondioxideforcarbonateddrinks,dryice,fireextinguishersandotherindustrialuses.Ingasification-basedpowerplantswith'pre-combustion'capturethecoalgasisreactedwithsteamtomakehydrogen,whichcanbeburntinagasturbinetoraiseelectricitywithoutproducingcarbondioxide.Newpowerplantsofeithertypeareexpectedtohavesimilarcostsandperformancewithcapture.Inthelongertermothertypesofcapturesystemmaybetriedouttoseeiftheycangivebetterperformance.Perhapsthebestknowoftheseisoxyfuelcombustion;pureoxygenisproducedandusedtoburnthecoal,givingnearlypureCO2withlittleadditionalprocessing.Buttherearealsoalotofwaysinwhichthecurrentpost-combustionandpre-combustionsystemscanbeimproved.So,aswithallothernewtechnologies,thereareplentyofopportunitiesforindustriestocompetetoproducebetterproductsandforuserstotakeadvantageofacompetitivemarketwithmultiplesuppliers.Thereisacatch:capturingcarbondioxidecostsmoney.Withcurrentdesignsabout25%extrafuelhastobeburntandadditionalequipmentmustbepurchased.Thisaddsbetween30and40%tothecostofelectricity.Thismayseemlikealot,butdividingtheextracostbytheamountofcarbondioxidethatisnotemittedtoatmospherehasbeenestimatedtogive'abatementcosts'of25-30€pertonneofCO2(250-300yuanorUS$30-38),apricealreadyreachedlastwinterintheEUEmissionsTradingScheme(ETS).Althoughcarbonpricesarenowlower,intheETSandtheinternationalCleanDevelopmentMechanism(CDM),itdoesshowthatfinancingCCSinChinacouldbequiteaneffectivewaytooffsetemissionselsewhereintheworld,especiallyastechnologyimprovesandcapturecostsgodown.Thekeyisreachinginternationalagreementtopursuesustainedandsignificantemissionreductions.AnotherwaytofinanceCCS,atleastatfirst,isthrough'enhancedoilrecovery'(EOR).Carbondioxide,compressedtoaliquid,canbeplacedundergroundinoldoilandgaswells.Inoilwells,thecarbondioxidecanhelptowashoutoilthatisstuckintheporesoftherockandcannotbereleasedbyothermeans.CurrentpricesintheUSAforcarbondioxideforEORarearound$20/tonneCO2.PetrochinaandCNOOCarecurrentlyexaminingsimilarEORschemesinChina.But,whileoldoilandgasreservoirsofferprovenleak-tightstorageandEORcangiveanextrasourceofrevenue,mostofthepotentialstoragecapacityforcarbondioxideinChina(andglobally)isindeeplayersofporousrockakilometreormoreundergroundthatcontainonlysaltywater,knownassalineaquifers.Oneofthese,undertheNorthSea,hasalreadybeenusedsuccessfullytostoreamilliontonnesofCO2ayearfromtheNorwegianSleipnergasplatform,andrequiresonlyasingleinjectionpipe.WhilewearewaitingforthenecessarypoliticalprogressonclimatechangemitigationtomakeCCSamarketableservice,WesterngovernmentshaveofferedtoworkwithChinatofindouthowmuchcarbondioxidecanbestoredundergroundinChinaandwherethebeststoragesitesmightbeandalsotobuildthefirstCO2captureplantsinChina.PreliminaryresultsfromanAustralianstoragecapacityprojectareshowninFigure1;thisworkwillbecontinuingwithateamofChineseandinternationalgeologists.WhileitheldtheEUPresidencyin2005theUKsetuptheUK-EU-ChinaNear-ZeroEmissionsCoal(NZEC)project,whichisplannedtoleadtoajointly-designedandconstructedpowerplantwithcarboncaptureandstoragestartingoperationby2014.TherearealsootherCCS-relatedresearchandcapacity-buildingprojectswiththeEUand,underbilateralagreements,withindividualcountriesandthenumberoftheseissettoincreasesignificantly.Figure1:LargesourcesofcarbondioxideinChinaandregionsforprospectivedeepgeologicalstorageinChinaChinacanalsofollowWesterndevelopmentsbyseeingthatnewpowerplantsarebuilttobe'capture-ready'.Thismeansthatafewsimpleandinexpensivechanges(principallyspaceintherightplacesandaccesstocarbondioxidestoragesites)areincludedatthedesignstagesothatcaptureequipmentcanbeaddedwithoutprohibitivecostsinthefuture.UtilitycompaniesbuildingpowerplantsinEuropeandtheUSAarealreadydoingthisintheirdomesticmarketstomakesuretheycanuseCCStoavoidlargecostpenaltiesforCO2emissionsinthefuture.Anotherenergy-relateddevelopmentthatpreparesforCCSisintroducingnewwaystouse'decarbonised'energy,electricityandhydrogen.Evenwhenthecarbondioxideproducedintheproductionprocessiscaptured,makingsyntheticgasolineordieselfuelfromcoalstillresultsinhalfofthecoalcarbonbeingemittedtoatmosphere.Incontra