汽車新能源與排放控制（雙語(yǔ)教學(xué)版）Chapter 5

Chapter5:AlternativefuelvehicleExample：Withinthetransportationindustry,includingtrucksanddeliveryvans,transitvehiclesaccountforlessthan2%ofthetotalfuelconsumed.Dieselisthemostcommonlyusedtransitfuel.Useofotherfuels,knownasalternativefuels,islimitedbutgrowing.Table5.1,basedonasurveyof300transitagenciesbytheAmericanPublicTransportationAssociation,showsthedominanceofpetroleumdieselfueluseintransitvehiclesofvarioustypes.Table5.1.SurveyofU.S.TransitVehiclesbyPowerSourceandTypeofVehicleQuestion:Whatarethemainalternativefuels?5.1AlternativeenergyThefollowingfuelsareconsideredalternativefuels:Alternativediesel(includingbiodiesel,Fischer-Tropschanddieselblends);Methanol,ethanol,andotheralcohols;Liquefiedpetroleumgas(propane);Blendsof85percentormoreofalcoholwithgasoline;Coal-derivedliquidfuels;Fuels(otherthanalcohol)derivedfrombiologicalmaterials;Naturalgasandliquidfuelsdomesticallyproducedfromnaturalgas;5.2AlternativefuelvehicleFig5.1ABrazilianfillingstationwithfouralternativefuelsforsale:biodiesel(B3),gasohol(E25),neatethanol(E100),andcompressednaturalgas(CNG).5.2Alternativefuelvehicle5.2.1AirengineFig5.2Airenginevehicle5.2Alternativefuelvehicle5.2.2DimethyletherfuelFig5.3InstallationofBioDMEsynthesistowersatChemrec'spilotfacility5.2Alternativefuelvehicle5.2.3AmmoniafuelledvehiclesFig5.4TheX-15aircraftusedammoniaasonecomponentfuelofitsrocketengine5.2Alternativefuelvehicle5.2.4BioalcoholandethanolFig5.5E85fuelsoldataregulargasolinestationinWashington,D.C.5.2Alternativefuelvehicle5.2.5BiodieselFig5.6Biodiesel(B20)pumpintheU.S.5.2AlternativefuelvehicleFig5.7Busrunningonsoybeanbiodiesel5.2Alternativefuelvehicle5.2.6CompressednaturalgasFig5.8BusespoweredwithCNGarecommonintheUnitedStates.Fig5.9TheBrazilianFiatSienaTetrafuel1.4,thefirstmultifuelcarthatrunsasaflexible-fuelonpuregasoline,orE25,orE100;orrunsasabi-fuelwithnaturalgas(CNG).5.2Alternativefuelvehicle5.2.7Liquefiedpropanegas(LPG)Fig5.10Apropane-fueledschoolbusintheUnitedStates.5.2Alternativefuelvehicle5.2.8FlexiblefuelFig5.11SixtypicalBrazilianfullflex-fuelmodelsfromseveralcarmakers,popularlyknownas"flex"cars,thatrunonanyblendofethanolandgasoline(actuallybetweenE20-E25toE100).5.3EmissionsfromAlternativeFuelsTable5.2:Comparisonofbusengineemissionswithemissionsstandards.(Levelsmeetingorexceedingstandardsshowninitalics).5.4Others5.4.1DieselEmulsionTheCaliforniaAirResourcesBoard(CARB)hascertifiedPuriNOx,ablendofdieselfuelwith20%water,asanalternativefuelaimedatthefleetmarket.However,concernsovercorrosionandemulsionstabilityhavenotyetbeenresolved.PuriNoxachievesa14%reductioninNOxanda63%reductioninPM,butisassociatedwith15%lossinoverallpower.LubrizolandCaterpillararecurrentlyundertakingdevelopmentworkinthisarea.5.4Others5.4.2Carbon‐neutralfuel5.4.3RapeMethylEster(RME)Carbonneutralfuelissyntheticfuel—suchasmethane,gasoline,dieselfuelorjetfuel—producedfromrenewableornuclearenergyusedtohydrogenatewastecarbondioxiderecycledfrompowerplantflueexhaustgasorderivedfromcarbonicacidinseawater.Suchfuelsarepotentiallycarbonneutralbecausetheydonotresultinanetincreaseinatmosphericgreenhousegases.RapeMethylEster(RME)producedfromoilseedrapehasasimilarconsistencytomineraldieselandisoftenreferredtoasbiodiesel.Tailpipeemissionsfromabiodieselvehiclecanbesimilartothatofmineraldieselvehicles.However,duringthefuelsproductionanduselifecycle(well-to-wheel),theremaybeglobalenvironmentaladvatages.5.4Others

5.5BarriersFacingAlternativeFuelsEveryalternativefuelimposessomecombinationofincreasedcapitalcosts,operatingcosts,technicalchallenges,orinstitutionalissuesascomparedtodieselfuel.Barriersthathaveinhibitedgreateruseofalternativefuelsinpublictransportationvehiclesinclude:?Highercapitalcostsofalternativefuelvehiclesandsupportingfacilities,especiallynaturalgasfacilitiesandelectrificationofroutesfortrolleybusesorcommuterraillines;?Higheroperatingcostsforitemslikethealternativefuelsthemselvesandmaintainingvehiclesandequipmentusingthem;?Unprovenreliabilityanddurabilityofearlyproductionmodelsofnewalternativefuelvehiclesthatcouldaffecttransitservicedependability;?Limitedavailabilityofnewalternativefuels;?Riskofinterruptionsinfueldelivery;?Theneedtodevelop,adoptandenforcecodesandstandardsforalternativefuelperformanceandstability,comparabletothoseusedinspecifyingdieselfuelquality;?Higherlogisticscostsofaddingaduplicativeinventoryofcomponentsandsparepartspeculiartothealternativefuelvehicles;and,?Costsofdevelopingnewoperatingandmaintenanceproceduresforhandlingalternativefuelsandconductingspecialtrainingformechanicsandvehicleoperators.Question:1What