能源储存课件(英文版)

1.Whatshouldwedoabouttheenergycrisis?Whichoneisthemostimportant?ChemicalEnergyStorageMagneticEnergyStorage.ThermalEnergyStorage.MechanicalEnergyStorageEnergyStorageSystem(ESS)canbeclassifiedasMechanicalEnergyStorage•Principle:EnergyisstoredintheformofMechanicalEnergy.•Lightweightfibercompositematerialsareusedtoincreaseefficiency.•Energydensity=0.05MJ/Kg,η=0.8FlyWheelsCompressedAirEnergyStorageOperation:Usesoff-peakelectricitytocompressairandstoreitinairtightundergroundcaverns.Whentheairisreleasedfromstorage,itexpandsthroughacombustionturbinetocreateelectricity.Energydensity=0.2~2MJ/Kg,η=0.5Advantagesanddisadvantages:Faststart-up.Drawback-GeologicalstructurereliancePumpedHydroelectricEnergyStorageOperation:Itconsistsoftwolargereservoirslocatedatdifferentelevations.Duringpeakdemand,waterisreleasedfromtheupperreservoir.IfProductionexceedsDemand,waterispumpedupandstoredintheupperreservoir.PumpusedisaCombinedMotorandDynamo.Advantagesanddisadvantages:Mosteffectivewithlargestcapacityofelectricity(over2000MW).Energydensity=0.001MJ/Kg,η=0.8Geographicaldependence.Thecapitalcostismassive.Soilerosion,landinundation,Siltingofdams.MagneticEnergyStoragePrinciple:Atlow-temperatures,electriccurrentsencounteralmostnoresistance.Storesenergyinthemagneticfield.EnvironmentalfriendlyandHighlyefficient.ReactorSuperCapacitorsPrinciple:Thedistancebetweenthetwochargedlayersisverysmall,resultinginaverylargecapacitanceLongservicelife,quickchargeanddischargeElectrochemicalEnergyStorageLeadacidBatterylithiumbatteryPrinciple:Theyuseachemicalreactiontodoworkonchargeandproduceavoltagebetweentheiroutputterminals.Energydensityis0.6MJ/Kg.ComparisonofdifferentbatteryenergystoragesystemsThermalEnergyStorage.Asalthydrateactsasacoolheatsinkfortheairconditionerworkingfluid.Thestoredheatisrejectedfromthesalthydrateduringnighttoheatthesurroundingair.Energydensity=0.25MJ/Kg,η=0.8E.g.:SodiumSulfateDecahydrate•Advantages:•Nogreenhousegases•Notmuchpoliticaldependence•Moreoperatingtime.Disadvantages:•StorageofHydrogenduetohighlyinflammablenatureofH2.HighcapitalcostduetoPlatinumcatalystusedintheprocess.FuelCellsWhichisbetter???1.Comparingonemethodofenergystoragewithanotherispointless.Thereason-Noneofthemareoptimalforallpurposes2.Flywheelshaveanarrowrangeandarenotananswerforlargescaleoperations.3.Differentstoragemethodsdifferincapacityandmaximumusablestoragetime.4.ForlargescalestorageUndergroundthermal,pumpedhydroandcompressedairenergystoragesystemsarepreferable.5.Superconductorscanstoreenergywithnegligiblelosses.6.Fuelcellsareaviablealternativetopetrolenginesduetotheirhighefficiency.