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HydrogenandFutureEnergySourcesWelearnedthatfossilfuelswereformedbeforeandduringthetimeofthedinosaurs-whenplantsandanimalsdied.Theirdecomposedremainsgraduallychangedovertheyearstoformcoal,oilandnaturalgas.Fossilfuelstookmillionsofyearstomake.Weareusingupthefuelsformedmorethan65millionyearsago.Theycan'tberenewed;theycan'tbemadeagain.Wecansavefossilfuelsbyconservingandfindingwaystoharnessenergyfromseemingly"endlesssources,"likethesunandthewind.Wecan'tusefossilfuelsforeverastheyareanon-renewableandfiniteresource.Somepeoplesuggestthatweshouldstartusinghydrogen.Hydrogenisacolorless,odorlessgasthataccountsfor75percentoftheentireuniverse'smass.HydrogenisfoundonEarthonlyincombinationwithotherelementssuchasoxygen,carbonandnitrogen.Tousehydrogen,itmustbeseparatedfromtheseotherelements.Today,hydrogenisusedprimarilyinammoniamanufacturing,petroleumrefiningandsynthesisofmethanol.It'salsousedinNASA'sspaceprogramasfuelforthespaceshuttles,andinfuelcellsthatprovideheat,electricityanddrinkingwaterforastronauts.Fuelcellsaredevicesthatdirectlyconverthydrogenintoelectricity.Inthefuture,hydrogencouldbeusedtofuelvehicles(suchastheDaimlerChryslerNeCar4showninthepicturetotheright)andaircraft,andprovidepowerforourhomesandoffices.Hydrogencanbemadefrommoleculescalledhydrocarbonsbyapplyingheat,aprocessknownas"reforming"hydrogen.Thisprocessmakeshydrogenfromnaturalgas.Anelectricalcurrentcanalsobeusedtoseparatewaterintoitscomponentsofoxygenandhydrogeninaprocesscalledelectrolysis.Somealgaeandbacteria,usingsunlightastheirenergysource,giveoffhydrogenundercertainconditions.Hydrogenasafuelishighinenergy,yetamachinethatburnspurehydrogenproducesalmostzeropollution.NASAhasusedliquidhydrogensincethe1970stopropelrocketsandnowthespaceshuttleintoorbit.Hydrogenfuelcellspowerthe shuttle'selectricalsystems,producingacleanby-product-purewater,whichthecrewdrinks.Youcanthinkofafuelcellasabatterythatisconstantlyreplenishedbyaddingfueltoit-itneverlosesitscharge.ToviewaFLASHvideoofhowafuelcellworks,gototheBallardPowerSystemswebsite.FuelCellUsesFuelcellsareapromisingtechnologyforuseasasourceofheatandelectricityinbuildings,andasanelectricalpowersourceforvehicles.Autocompaniesareworkingonbuildingcarsandtrucksthatusefuelcells.Inafuelcellvehicle,anelectrochemicaldeviceconvertshydrogen(storedonboard)andoxygenfromtheairintoelectricity,todriveanelectricmotorandpowerthevehicle.Althoughtheseapplicationswouldideallyrunoffpurehydrogen,intheneartermtheyarelikelytobefueledwithnaturalgas,methanolorevengasoline.Reformingthesefuelstocreatehydrogenwillallowtheuseofmuchofourcurrentenergyinfrastructure-gasstations,naturalgaspipelines,etc.-whilefuelcellsarephasedin.Inthefuture,hydrogencouldalsojoinelectricityasanimportantenergycarrier.Anenergycarrierstores,movesanddeliversenergyinausableformtoconsumers.Renewableenergysources,likethesun,can'tproduceenergyallthetime.Thesundoesn'talwaysshine.Buthydrogencanstorethisenergyuntilitisneededandcanbetransportedtowhereitisneeded.Someexpertsthinkthathydrogenwillformthebasicenergyinfrastructurethatwillpowerfuturesocieties,replacingtoday'snaturalgas,oil,coal,andelectricityinfrastructures.Theyseeanew"hydrogeneconomy"toreplaceourcurrent"fossilfuel-basedeconomy,"althoughthatvisionprobablywon'thappenuntilfarinthefuture.SolarPowerSatellites Onesuggestionforenergyinthefutureistoputhugesolarpowersatellitesintoorbitaroundtheearth.Theywouldcollectsolarenergyfromthesun,convertittoelectricityandbeamittoEarthasmicrowavesorsomeotherformoftransmission.Thepowerwouldhavenogreenhousegasemissions,butmicrowavebeamsmightaffecthealthadversely.Andfrequentrocketlaunchesmayharmtheupperatmosphere.Thisideamaynotbepracticalforanothercentury;ifatall.ThepictureontherightisanearlyandsimpledrawingofhowaspacesolarpowersatellitewouldbeamenergytoelectricalpowergridonEarth.OtherIdeasSomepeoplehaveclaimedthey'veinventedamachinethatwill"savetheplanet."Othersareconvincedthatthere'savastconspiracybyfossilfueland/ornuclearpowercompaniestostopsuchdevicesfromgettingtothepublic.Someofthesecontraptionsusetheoriescalled"FreeEnergy,""OverUnity"or"Zero-PointEnergy."Asamatteroffact,youcanfindallsortsofinformationaboutsuchdevicesontheInternet.Justpluginanyofthosewords.Butnoneofthesedeviceshaveeverbeenproven,eithertheoreticallyorphysically.The"freeenergy"areaisfilledwithconartistssellingunintelligibleinformation,oftencloudedwithtechnicalsoundingjargon,andseekingpeoplewithmoneytodeveloptheirinventionsorideas.Astheoldsayinggoes,"afoolandhismoneyaresoonparted."Mostofthesedevicesareperpetualmotionmachines,whichviolateknownlawsofscience.EventheU.S.PatentOfficewillnotissueapatentforsuchdevices.Withenergyandtheuniverse(atleastasweknowittoday),there'snosuchthingasafreelunch;orfreeenergy.Youcan'tgetenergyfromnothingbecauseofthefundamentallawsofphysicsthatenergycannotbecreatedordestroyed.Whataboutmatterandanti-matter?WhataboutenergythattheyuseonStarTrekandinothersciencefictionstories?Theideasareinteresting,buttheyarestill fiction.Thoughsciencefictionhasabasisinsomefact.JulesVernewroteabouttravelingunderthewatermorethanahundredyearsago,andtodaywehavesubmarines.Healsowroteaboutgoingtothemoon,andin1969humansfirstsetfootonourclosestneighborinspace.So,whilesomeideasbeingusedbywritersarefiction...therecouldbesomebasisinfact.Whoknows,someonemightcreateamater-antimatterenergysystemthatcouldrevolutionizethewaywethinkaboutenergyandouruniverse.
