EnergysystemanalysisoftheimplicationsofhydrogenfuelcellvehiclesintheSwedishroadtransportsystemMa˚rtenLarssona,*,FarzadMohsenib,CeciliaWallmarkb,StefanGr€onkvista,PerAlvforsaaDepart.ofChemicalEngineeringandTechnology,KTHeRoyalInstituteofTechnology,SwedenbSWECO,SwedenarticleinfoArticlehistory:Received11February2015Receivedinrevisedform29April2015Accepted30April2015Availableonline28May2015Keywords:FuelcellelectricvehiclesHydrogenEnergysystemTransportWell-to-wheelefficiencyabstractThefocusonpathwaystoreducetheuseoffossilfuelsinthetransportsectorisintenseinmanycountriesworldwide.Consideringthatbiofuelshavealimitedtechnicalproductionpotentialandthatbatteryelectricvehiclessufferfromtechnicallimitationsthatputcon-straintsontheirgeneraluseinthetransportsector,hydrogen-fuelledfuelcellvehiclesmaybecomeafeasiblealternative.Introductionofhydrogeninthetransportsectorwillalsotransformtheenergysectorandcreatenewinteractions.TheaimofthispaperistoanalysetheconsequencesandfeasibilityofsuchanintegrationinSweden.Differentpathwaysforhydrogen,electricityandmethanetothetransportsectorarecomparedwithregardtosystemenergyefficiency.Thewell-to-wheelenergyefficienciesforhydrogenandelectricityareusedforestimatingtheenergyresourcesneededforhydrogenproductionandelectricvehiclesforafutureSwedishtransportsectorbasedonrenewablefuels.Theanalysisrevealthatthewell-to-wheelsystemefficienciesforhydrogenfuelcellvehiclesarecomparabletothoseofmethanegasvehicles,evenwhenbiomethaneistheenergysource.TheresultsfurtherindicatethatanincreasedhydrogendemandmayhavealessthanexpectedimpactontheprimaryenergysupplyinSweden.Copyright©2015,HydrogenEnergyPublications,LLC.PublishedbyElsevierLtd.Allrightsreserved.IntroductionTheSwedishroadtransportsectorisheavilydependentonfossilenergysourcesandthetransitiontorenewableorlowcarbonenergyappearstobemoredifficultandcostlythanintheenergyutilitysector.In2012,thetotalenergyend-useintheSwedishroadtransportsectorwas87TWh,and8.1%ofthiswasbiofuels(biodiesel,ethanolandbiogas)[1].Inthesameyear,theelectricitymixconsistedof48%hydropower,4%windpower,38%nuclearpower,andthe10%combustionbasedcombinedheatandpowertowhich73%oftheprimaryenergyinputwasbiomass[1].Thetransitiontovehicletech-nologiesthatuserenewableenergysourcesiscrucialtoreducethetransportsector'simpactontheglobalclimateaswellasonlocalairquality.Electricvehicleswithenergystoredinbatteriesorhigh-pressurehydrogentankscanbeapartof*Correspondingauthor.DivisionofEnergyProcesses,Teknikringen42,SE-10044Stockholm,Sweden.Tel:þ4687906551.E-mailaddress:martel@kth.se(M.Larsson).Availableonlineat(2015)11722e11729©2015,HydrogenEnergyPublications,LLC.PublishedbyElsevierLtd.Allrightsreserved.thesolutionforbothproblems.Electricvehicleswithbatteriesareenergyefficientbut,withthecurrentbatterytechnology,limitedinrange,whilecompressedhydrogeninfuelcellelectricvehicles(FCEV)providesufficientrangebutinfersenergylossesduringtheproductionofhydrogenfollowedbyanenergydemandforcompressionanddistribution.Theadvantagesofboththesetypesofelectricvehiclescantosomeextentbecombinedinplug-inFCEVs,butmanyuncertaintiesremainforthistypeofvehicles,forexamplehowtoachievereasonablecosts[2].Furthermore,toachievehighenergyefficiencyandreducedegradationinthevehiclesystems,asuitabledegreeofhybridizationandenergymanagementstrategymustbedeveloped[2].Vehiclesfuelledbyelectricityorhydrogenwillintegratetheenergyutilitysectorwiththeroadtransportsectorwiththebenefitsofintroducingmorerenewableenergysourcesfromthefirsttothelatterwhilepossiblyprovidingloadbalancingopportunitiesforanincreasinglycomplexpowersystem.Batteryelectricvehicleshavecommonlybeensuggestedforloadbalancingpurposes,andsohaveplug-inFCEVs[2].BothelectricvehicleswithbatteriesandFCEVsareprob-ablynecessarytoachievetargetssetbytheEuropeanUnionandtheSwedishGovernment.Targetsfortheshareofrenewableenergy,greenhousegasemissionreductions,andenergyefficiencyuntil2020areinplaceintheEuropeanUnion,togetherwithaspecifictargetof10%renewableenergyinthetransportsector[3].Asacontinuationofthe2020goals,additionalbindingtargetsuntil2030havebeenproposedbytheEuropeanCommission:27%renewableenergyand40%reductionofgreenhousegasemissionscomparedto1990[4].Anon-bindingtargetforthetransportsectorhasbeensetuntil2050:60%reductionofthegreenhousegasemissionsinthetransportsectorandnoconventionallyfuelledvehiclesinthecities[5].AccordingtoanexpertgroupestablishedbytheEuropeanCommissiontoevaluatefuturetransportfuels,arangeoftechnologiesmaybenecessarytoreplaceconven-tionalfuelsinthetransportsector[6]:-Electricityinbatteryelectricvehicles(BEV)forshortdistances.-Hydrogenandmethaneformediumdistance.-Liquidbiofuels,syntheticfuelsandliquidmethaneforlongertransportsandheaviervehicles.TheEuropeanCommissionhasissuedadirectivewiththegoalofprovidingthemembercountriesaccesstoinfrastruc-tureformethane,electricityandhydrogen(optional)forthetranspo