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EnergyResourcesChapter10EnergyResources•Supplementingfreesolarenergy–99%ofheatcomesfromthesun–Withoutthesun,theearthwouldbe–2400C(-4000F)•Wesupplementtheother1%withprimarilynon-renewableenergysourcesEnergyResources•Renewable(16%)–Solar–Wind–Falling,flowingwater–Biomass•Non-renewable(84%)–Oil–Naturalgas–Coal–NuclearpowerEnergysourcesanduses•Energyusesindevelopedcountries–industrial–domestic–transportation•Note:Electricityisnotanenergysource,convertedfromanothersource(coal,hydro,nuclear,etc.).•1stLawofThermodynamics-Youcan’tgetmoreenergyoutofsomethingthanyouputin•2ondLaw–Inanyconversionofheatenergytousefulwork,someenergyisalwaysdegradedtoalowerqualityenergyEvaluatingEnergyResources•Renewable•Futureavailability•Netenergyyield•Ittakesenergytogetenergy•Habitatdegradation•Cost(initialandongoing)•Communitydisruption•Politicalorinternationalissues•Suitabilityindifferentlocations•Polluting(air,water,noise,visual)EachtypeofpowerprojectneedstobeevaluatedforthebenefitsandcostsTheenvironmentalcostsofhydroelectricityaremuchdifferentthanwindpower,forexampleImportantNonrenewableEnergySourcesNorthAmericanEnergyResourcesAverageAmericanusesinonedaywhatapersoninthepoorestcountriesuseinoneyearUShasonly2.4%ofworld’soilreservesOILandNATURALGAS•Accumulationsofdeadmarineorganismsontheoceanfloorwerecoveredbysediments.•Muddyrockgraduallyformedrock(shale)containingdispersedoil.•Sandstoneformedontopofshale,thusoilpoolsbegantoform.•Naturalgasoftenformsontopofoil.•PrimarycomponentofnaturalgasismethaneOil•Petroleum(crudeoil)•Costs:•Recovery•Refining•Transporting•Environmental•Highestrisksareintransportation•Refiningyieldsmanyproducts•Asphalt•Heatingoil•Diesel•Petrochemicals•Gasoline•…BasedonboilingpointsConventionalOilAdvantages•Relativelylowcost•Highnetenergyyield•EfficientdistributionsystemDisadvantages•Runningout•42-93years•Lowpricesencouragewaste•Airpollutionandgreenhousegases•WaterpollutionArcticNationalWildlifeRefugeControversy:Trade-offs•Wouldcreatejobs•Oilresourcesareuncertain•USsupply7-24months•UncertainenvironmentalimpactsOilShaleandTarSandsTarSand:Mixtureofclay,sandwaterandbitumen-athickandstickyheavyoil.Extractedbylargeelectricshovels,mixedwithhotwaterandsteamtoextractthebitumen.Bitumenheatedtoconverttosyntheticcrudeoil.OilShale:Oilyrocksthatcontainasolidmixofhydro-carbons.Globalsupplies~240timesconventionaloilsupplies.NaturalGas•50-90%methane•Cleanestoffossilfuels•Approximate200yearsupply•AdvantagesanddisadvantagesCoal–Whatisit?•Solidfossilfuelformedinseveralstages•Landplantsthatlived300-400millionyearsago•Subjectedtointenseheatandpressureovermanymillionsofyears•Mostlycarbon,smallamountsofsulfurCoalFormationandTypesCoal–whatdoweuseitfor?•Stagesofcoalformation•300millionyearoldforests•peatlignitebituminousanthracite•Primarilystrip-mined•Usedmostlyforgeneratingelectricity•Usedtogenerate62%oftheworld’selectricity•Usedtogenerate52%oftheU.S.electricity•Enoughcoalforabout200-1000years•U.S.has25%ofworld’sreserves•Highenvironmentalimpact•CoalgasificationandliquefactionCoal:Trade-offsWorld’smostabundantfossilfuelMiningandburningcoalhasasevereenvironmentalimpactAccountsforover1/3oftheworld’sCO2emissionsNuclearEnergy–Whatisit?•Anuclearchangeinwhichnucleiofcertainisotopeswithlargemassnumbersaresplitapartintolighternucleiwhenstruckbyneutrons.–Nuclei–centerofanatom,makingup0mostoftheatom’smass–Isotopes–twoormoreformsofachemicalelementthathavethesamenumberofprotonsbutdifferentmassnumbersbecausetheyhavedifferentnumbersofneutronsintheirnuclei.–Neutron–elementaryparticleinallatoms.–Radioactivity–Unstablenucleiofatomsshootout“chunks”ofmassandenergy.NuclearEnergy•Fissionreactors•Uranium-235•Fission•Resultingheatusedtoproducesteamthatspinsturbinestogenerateelectricity•ProducesradioactivefissionfragmentsLightwatergenerator–usedinallU.S.and85%worldwide.Greatdangeroflosingcoolant!LocationsofU.S.NuclearPowerPlantsTheNuclearFuelCycleProduceshighlyradioactivematerialsthatmustbestoredsafelyfor10,000-240,000years.ConventionalNuclearPower:Trade-offsNonewplantsinU.S.since1978.All120plantsorderedin1973havebeencancelled.Costover-runsHighoperatingcostsThreeMileIslandChernobylThreeMileIsland-Pennsylvania•March28,1979-PartialCoreMelt-Down.•NoDeaths.•VeryLittleRadiationVented.•PublicRelationsDisaster.Chernobyl–Ukraine(FormerUSSR)•April26,1986•Oneoffourreactorsexplodes.•31immediatedeaths.•116,000peopleevacuated.•24,000evacueesreceivedhighdosesofradiation.•Thyroidcancerinchildren.•Damagedreactorentombedinconcrete,otherreactorsreturnedtoservicewithinmonths.•Eventually,remainingreactorsoutofservice.DealingwithNuclearWaste•High-andlow-levelwastes•Terroristthreats–storagecaskshold5-10Xmoreling-livedradioactivitythanthenuclearpowerplant•Disposalproposals•Undergroundburial•Disposalinspace(illegalunderinternationallaw)•Burialinicesheets(““)•Dumpingintosubductionzones(““)•Burialinoceanmud(““)•Conversionintoharmlessmaterials(nowaytodothiswithcurrenttechnology)YuccaMountain•In1982,Congresscalledforahigh-levelradioactivedisposalsitetobeselectedbyMarch1987,andtobecompleted