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MACHINERYANDENERGYSYSTEMS FORTHEHYDROGENECONOMY MACHINERY ANDENERGY SYSTEMSFORTHE HYDROGEN ECONOMY Editedby KLAUS BRUN
ElliottGroup,Jeannette,PA,UnitedStates
TIMOTHY ALLISON
MachineryDepartment,SouthwestResearchInstitute,SanAntonio,TX,UnitedStates
Elsevier
Radarweg29,POBox211,1000AEAmsterdam,Netherlands
TheBoulevard,LangfordLane,Kidlington,OxfordOX51GB,UnitedKingdom 50HampshireStreet,5thFloor,Cambridge,MA02139,UnitedStates
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ThisbookandtheindividualcontributionscontainedinitareprotectedundercopyrightbythePublisher(other thanasmaybenotedherein).
Notices
Knowledgeandbestpracticeinthisfieldareconstantlychanging.Asnewresearchandexperiencebroadenour understanding,changesinresearchmethods,professionalpractices,ormedicaltreatmentmaybecome necessary.
Practitionersandresearchersmustalwaysrelyontheirownexperienceandknowledgeinevaluatingandusing anyinformation,methods,compounds,orexperimentsdescribedherein.Inusingsuchinformationormethods theyshouldbemindfuloftheirownsafetyandthesafetyofothers,includingpartiesforwhomtheyhavea professionalresponsibility.
Tothefullestextentofthelaw,neitherthePublishernortheauthors,contributors,oreditors,assumeanyliability foranyinjuryand/ordamagetopersonsorpropertyasamatterofproductsliability,negligenceorotherwise,or fromanyuseoroperationofanymethods,products,instructions,orideascontainedinthematerialherein.
ISBN:978-0-323-90394-3
ForinformationonallElsevierpublications visitourwebsiteat https://www.elsevier.com/books-and-journals
CoverImageCredit: ElliottGroupandSouthwestResearchInstitute
Publisher: CharlotteCockle
AcquisitionsEditor: PeterAdamson
EditorialProjectManager: JudithClarissePunzalan
ProductionProjectManager: PoulouseJoseph
CoverDesigner: MilesHitchen
TypesetbySTRAIVE,India
Contents Contributorsix
Abouttheeditorsxi Prefacexiii Acknowledgmentsxvii
1.Machineryintheenergyfuture
RobertB.Laughlin
1.1Thehydrogeneconomy1
1.2Energysources2
1.3Theroleofmachinery3
1.4Competitionwithelectrochemistry4 1.5Ongoingissues5
1.6Machineryintheenergyfuture6 References6
A Hydrogenbackground
2.Fundamentals WentingSun,SubithVasu,andMatthewS.Blais
2.1Physicalandchemicalpropertiesof hydrogen11
2.2Fundamentalhydrogenreaction kinetics14
2.3Hydrogencombustionproperties22 References28
3.Machinerybasics BrianPettinato,RainerKurz,LeonidMoroz,ZahroofMohamed, SebastianFreund,BernhardWinkelmann,andEnverKarakas
3.1Introduction31 3.2Machinery36
References92 Furtherreading94
4.Heatengines JoshuaSchmitt,ThomasBriggs,TimothyCallahan, SebastianFreund,RainerKurz,AdamNeil,GuillermoPaniagua, andDavidSa ´ nchez
4.1Thermodynamicprinciples95
4.2Conventionalenginecycles113
4.3Emergingcycleinnovations143 References184
B Hydrogenapplicationsandmarkets
5.Supplyprocessesandmachinery
ThomasI.Valdez,JasonMunster,EricMiller,andSebastianFreund
5.1Introduction191
5.2Thecolorofhydrogen192
5.3Coalgasification192
5.4Hydrogenreformationprocesses194
5.5Emergingtechnologies209
5.6Hydrogennaturalgasmixturecompatibilityand separationoptions212 References213
6.Transportandstorage RainerKurz,BernhardWinkelmann,SebastianFreund, MarybethMcBain,MarkKeith,DonghuiZhang,StefanCich, PeterRenzi,andJoshuaSchmitt
6.1Introduction215
6.2Pipelinetransport218
6.3Transportconsiderationsforblue,turquoise,and greenhydrogen230
6.4Shippingliquidhydrogen231
6.5Transportbytrucks232
6.6Hydrogentransportandstoragewithother chemicals238
6.7Hydrogenstorage241 References247
Furtherreading249
7.Usage ToddOmatick,DonghuiZhang,MatthewS.Blais,MounirMossolly, PeterRenzi,RainerKurz,SebastianFreund,andShaneHarvey
7.1Introduction252
7.2Hydrogenusedtoproduceelectricity—Power generationplants252
7.3Automotivetransportation274
7.4Othertransportation278
7.5Refineryandchemicalindustry(includingbio refineryandLNG)288
7.6Distribution293
References302
Furtherreading304
8.Economicsofhydrogenfuel RobertB.LaughlinandSebastianFreund
8.1Introduction305
8.2Hydrogenenergycontent306
8.3Presenthydrogenprice309
8.4Presenthydrogenproduction310
8.5Arbitrageissues312
8.6Theoreticalprices:Gray,blue,andgreen313
8.7Fuelcellsvs.mechanicalengines315
8.8Electrochemistrycostissues317
8.9Carbonsequestrationcostissues321 References327
9.Compressorsandexpanders JeffreyMoore,JonDurham,AndreEijk,EnverKarakas,RainerKurz, JosephLesak,MarybethMcBain,PatrickMcCalley,LeonidMoroz, ZahroofMohamed,BrianPettinato,GregPhillippi, HideharuWatanabe,andBenWilliams
9.1Centrifugalcompressors334
9.2Reciprocatingcompressors347
9.3Diaphragmcompressors397
9.4Screwcompressors399
9.5Compressorstationandpipelineconsiderations forhydrogenmixtures406
9.6Featuresofhydrogenturboexpanders408
9.7Hydrogenliquefaction414
References423
Furtherreading424
10.Powergenerationandmechanical drivers
JasonWilkes,MarybethMcBain,RainerKurz,JeffreyGoldmeer, TimothyCallahan,KarlWygant,JaswinderSingh,BrennaGeswein, andSebastianFreund
10.1Gasturbines(Rainer,Mounir,Goldmeer, Freund)426
10.2Gasengines447
10.3Risksassociatedwithhydrogenpowergeneration equipment461
References466
Furtherreading470
D Materialsandsafetyconsiderations
11.Materialsforthehydrogeneconomy
MichaelA.Miller,DerrickBauer,JohnMacha,EugeneBroerman,III, ElizabethTrillo,andFassettHickey
11.1Introduction477
11.2Hydrogeninteractionsandeffectsonmaterial performance481
11.3Characterizationofhydrogensolubility, trapping,andtransportinmetals485
11.4LTDMSanalysis492
11.5Materialsforhigh-pressure hydrogencompressionandtransportation502
11.6Magneticmaterialsandbondingagentsfor hydrogenmachinery513
References518
12.Safety EugeneBroerman,III,MatthewS.Blais,NathanWeyandt,and PeterRenzi
12.1Introduction521
12.2Operationalissues521
12.3Safetyeventsandlessonslearned526
12.4Codesandstandards529
References542
E Researchandtesting 13.Majortestfacilities,pilotplants,and R&Dprojects
MichaelMarshall,GriffinBeck,EugeneBroerman,III, EugenioTrilloLeo ´ n,andToshiichiMatsumoto
13.1Introduction546
13.2HydrogentestfacilitiesandR&Dprogramsin theUnitedStates546
13.3HydrogentestfacilitiesandR&Dprogramsin SpainandotherEuropeancountries(Eugenio TrilloLeo ´ n)553
13.4HydrogentestfacilitiesandR&Dprojectsin Japan560
References575
14.Novelandleading-edgetechnology development
SubithVasu,RaghuKancherla,PeterdeBock,ZahroofMohamed, EugeneBroerman,III,andMichaelOhadi
14.1Hydrogenfromsolarthermalenergy577
14.2Hydrogenfromwindenergy583
14.3Hydrogenfromnuclearenergy584
14.4Hydrogenfromhydropower586
14.5Hydrogenfromtidalpower586
14.6Hydrogenfromoceanicthermalenergy conversion587
14.7Alternativehydrogencarriers588
14.8Advancedcompressorsandvalves590
14.9Advancesinheatexchangers:High-temperature andhigh-pressureheatexchangersforhigh efficiencyandlightenergyconversion systems597
References601
15.Greenhydrogenmarketandgrowth SebastianFreundandDavidSanchez
15.1Thehydrogenmarket605
15.2Greenandlow-carbonhydrogen609
15.3TheEUhydrogenstrategy—Aphased approach614
15.4Fundamentalsofhydrogenproductionthrough waterelectrolysis615
15.5TechnicalfeasibilityoftheEUtargetsfor2024 and2030:Hydrogengenerationcapacity619
15.6Requirementsforadditionalrenewablepower generationcapacityandstressonmarket deployment622
15.7Discussion625
15.8Economicconsiderationsabouttheimpactof renewableenergydeploymentonthepriceof electricity(andhydrogen)626
15.9Conclusion633
References634
Nomenclature637 Index643
Contributors DerrickBauer ElliottGroup,Jeannette,PA, UnitedStates
GriffinBeck SouthwestResearchInstitute,San Antonio,TX,UnitedStates
MatthewS.Blais SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
PeterdeBock DepartmentofEnergy,Advanced ResearchProjectsAgency-Energy,Washington, DC,UnitedStates
ThomasBriggs SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
EugeneBroerman,III SouthwestResearch Institute,SanAntonio,TX,UnitedStates
TimothyCallahan SouthwestResearch Institute,SanAntonio,TX,UnitedStates
StefanCich SouthwestResearchInstitute,San Antonio,TX,UnitedStates
JonDurham Aerzen,Katy,TX,UnitedStates
AndreEijk Consultant,Delft,TheNetherlands
SebastianFreund EnergyfreundConsulting, Unterfohring,Munich,Germany
BrennaGeswein CaterpillarO&G,Peoria,IL, UnitedStates
JeffreyGoldmeer GEGasPower,Schenectady, NY,UnitedStates
ShaneHarvey ElliottGroup,Jeannette,PA, UnitedStates
FassettHickey SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
RaghuKancherla PowerSystemsMfg.,LLC, Jupiter,FL,UnitedStates
EnverKarakas ElliottGroup,Jeannette,PA, UnitedStates
MarkKeith NikolaMotorCompany,Phoenix, AZ,UnitedStates
RainerKurz SolarTurbines,SanDiego,CA, UnitedStates
RobertB.Laughlin DepartmentofPhysics, StanfordUniversity,Stanford,CA,United States
EugenioTrilloLeo ´ n LeanHydrogen,Mairena delAljarafe,Seville,Spain
JosephLesak NeumanandEsser,Katy,TX, UnitedStates
JohnMacha SouthwestResearchInstitute,San Antonio,TX,UnitedStates
MichaelMarshall SouthwestResearch Institute,SanAntonio,TX,UnitedStates
ToshiichiMatsumoto TheInstituteofApplied Energy,Tokyo,Japan
MarybethMcBain KinderMorgan,Houston, TX,UnitedStates
PatrickMcCalley NeumanandEsser,Katy,TX, UnitedStates
EricMiller DepartmentofEnergy,Washington, DC,UnitedStates
MichaelA.Miller SouthwestResearch Institute,SanAntonio,TX,UnitedStates
ZahroofMohamed ZahroofCorp.,Houston, TX,UnitedStates
JeffreyMoore SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
LeonidMoroz SoftInWay,Inc.,Burlington,MA, UnitedStates
MounirMossolly TechnipEnergies,laDefense, NanterreCEDEX,France
JasonMunster CleanEpicAdvising,Long Beach,CA,UnitedStates
AdamNeil ElliottGroup,Jeannette,PA,United States
MichaelOhadi UniversityofMaryland,College Park,MD,UnitedStates
ToddOmatick ElliottGroup,Jeannette,PA, UnitedStates
GuillermoPaniagua PurdueUniversity,West Lafayette,IN,UnitedStates
BrianPettinato ElliottGroup,Jeannette,PA, UnitedStates
GregPhillippi ArielCorp.,Mt.Vernon,OH, UnitedStates
PeterRenzi PrafisEnergySolution,Richmond, TX,UnitedStates
DavidSa ´ nchez UniversityofSeville,Seville, Spain
JoshuaSchmitt SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
JaswinderSingh CaterpillarO&G,Peoria,IL, UnitedStates
WentingSun GeorgiaInstituteofTechnology, Atlanta,GA,UnitedStates
ElizabethTrillo SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
ThomasI.Valdez TeledyneEnergySystems Incorporated,Baltimore,MD,UnitedStates
SubithVasu UniversityofCentralFlorida, Orlando,FL,UnitedStates
HideharuWatanabe ElliottGroup,Jeannette, PA,UnitedStates
NathanWeyandt SouthwestResearchInstitute, SanAntonio,TX,UnitedStates
JasonWilkes SouthwestResearchInstitute,San Antonio,TX,UnitedStates
BenWilliams ArielCorp.,Mt.Vernon,OH, UnitedStates
BernhardWinkelmann NikolaMotor Company,Phoenix,AZ,UnitedStates
KarlWygant HanwhaPowerSystems, Houston,TX,UnitedStates
DonghuiZhang NikolaMotorCompany, Phoenix,AZ,UnitedStates
Abouttheeditors KlausBrun istheDirectorofResearchandDevelopmentatElliottGroup,Pennsylvania, UnitedStates.Hispastexperienceincludespositionsinproductdevelopment,applications engineering,projectmanagement,andexecutivemanagementatSouthwestResearchInstitute,SolarTurbines,GeneralElectric,andAlstom.Heholds10patents,hasauthoredmore than350papers,andpublishedfivetextbooksonenergysystemsandturbomachinery.He isafellowoftheAmericanSocietyofMechanicalEngineersandwonanR&D100award in2007.HealsowontheASMEIndustrialGasTurbineAwardin2016and12individual ASMETurboExpoBestPaperawards.Hehaschairedseverallargeconferencesincluding theASMETurboExpoandtheSupercriticalCO2 PowerCyclesSymposium.Heisamember oftheGlobalPowerPropulsionSocietyBoardofDirectorsandthepastchairoftheASME InternationalGasTurbineInstituteBoardofDirectors.Dr.BruniscurrentlytheExecutive Correspondentof TurbomachineryInternationalMagazine andanassociateeditorofseveral journaltransactions.
TimothyAllison istheDirectorofMachineryDepartmentatSouthwestResearchInstitute,Texas,UnitedStates,whereheleadsanorganizationthatfocusesonR&Dfortheoil andgas,propulsion,andenergyindustries.Hisresearchexperienceincludesanalysis,fabrication,andtestingofturbomachineryandsystemsforadvancedpoweroroilandgasapplicationsincludinghigh-pressureturbomachinery,centrifugalcompressors,expanders,gas turbines,reciprocatingcompressors,andtestrigsforbearings,seals,bladedynamics,and aerodynamicperformance.Dr.Allisonholdstwopatents,hasauthoredfourbookchapters, editedonebook,andhaspublishedmorethan70articlesonvariousturbomachinerytopics. Hereceivedthebesttutorial/paperawardsfromtheASMETurboExpoOilandGasand SupercriticalCO2 PowerCycleCommitteesin2010,2014,2015,and2018.Hehaschaired orco-chairedthosetwoASMETurboExpocommitteesandorganizingcommitteesfor theSupercriticalCO2 PowerCyclesSymposium,theIndustrialProcessEmissionsReduction Workshop,andtheThermal-Chemical-MechanicalEnergyStorageWorkshop.Heisan advisorycommitteememberforthe2022ASMEAdvancedCleanEnergySummitandan associateeditorfortheASMEJournalofEngineeringforGasTurbinesandPower.
Preface Thehydrogeneconomyanditstechnologyneedsareofsignificanteconomic,political,andacademicinterestinthemovement towardthedecarbonizationofmultipleenergysectors.Hydrogenisthemostcommon elementintheuniverseandthethirdmost commonelementonEarth;however,itis highlyreactivewithotherelements,soitis nearlyalwaysfoundinmolecularformcombinedwithoxygenaswaterorwithcarbonas anorganiccompound.Purehydrogenisattractiveasazero-carbonfuelbecauseitcan bestoredinlargevolumesoverlongdurationsandisalreadycompatibleinlowto moderateconcentrationswithexisting energyequipmentincludingsteamboilers, gasengines,gasturbines,industrial heaters/burners,andresidentialappliances. Thepetrochemicalindustryanditssupplier basehaveoperatedhydrogenpipelines, compressors,andgeologicstorageformany years,providingamaturetechnologybasis formanyhydrogeneconomyneeds.However,significantinfrastructurechangesare stillrequiredtomeettheproduction,transportation,storage,andusageneedsfora properlyfunctioninghydrogeneconomy. Thisincludesmachinerysuchascompressors,turbines,andpumpsaswellasheatenginesthatareverydifferentfromthose currentlyinstalledonpipelines,trucks, barges,andpowerplants.Forhydrogento beaviableenergycarrierinthefutureeconomy,machineryandpowercyclesmustoperatesafely,efficiently,andreliably;most importantly,theymustbeeconomically viable.
Asaresultofincreasingclimatestewardshipandcostreductionsforrenewablesolar andwindtechnologiesinthepastdecade, therehavebeensignificantchangestothe powergenerationmixonglobalandlocal scales.In2018,fossil-basedsystems accountedfor64.2%ofglobalpowergeneration,supplementedby10.2%nuclearpower. Theremaining 25%wasproducedbyrenewablesourcesincludinghydroelectric (15.8%),wind(4.8%),solar(2.2%),andgeothermal/biomass(2.4%combined).Althoughwindandsolarsourcesremaina relativelylowpercentageoftheoverallenergymix,theyarethefastest-growingcategoriesglobally,particularlyfordeveloped countries.From2017to2018,thesecountries saw19.8%and7.0%growthinsolarand windproduction,respectively.Inlocalregions,moredramaticchangescanbeseen; forexample,California’selectricityproductionprofileshowsthatcoal-basedelectricity hasdeclinedtonegligibleamounts.Renewableshavegrownrapidlyinthepastdecade, combiningfor21%growth.In2018,renewablesourcesincludingsolar,wind,hydro, geothermal,andbiofuelswereaclosesecond tonaturalgas,providing44%ofCalifornia’s electricityproduction.
Numerousgovernmentinitiativesacross theworldaretargetingadrasticreduction incarbonemissionsfromenergysectorsincludingelectricpower,transportation,and manufacturing.TheParisAgreement establishedin2016setagoaloflimiting globaltemperaturerisetolessthan2°C,to beachievedinpartbyloweringgreenhouse
gasemissionsandincreasingenergyproductionfromrenewablesources.Thisagreement hasbeensignedby186statesandtheEuropeanUnion,representingnearly97%of globalgreenhousegasemissions.Insupport ofthis,manycountrieshaveannouncedaggressivetargetsforcuttingCO2 andother greenhousegasemissionssignificantly (e.g.,50%and55%reductionsfortheUnited StatesandtheEuropeanUnion,respectively) by2030,andinmanycases,tonet-zero by2050.Toencouragethedevelopmentof enablingtechnologiesforachievingthese targets,government-fundedresearchprogramsarebeingorganizedincludingthe UnitedStates.DepartmentofEnergy’sEnergyStorageGrandChallenge,Energy “Earthshots”initiativesincludinga“HydrogenShot”targetinglow-costhydrogen,and the“H2@Scale”initiativetargetinglargescalehydrogeninfrastructure.
Twosignificantchallengesresultfromthe rapidintroductionofrenewableresources intotheenergymix.First,muchofthecapacitygrowthwillbeprovidedfromsolarphotovoltaicandwindgeneratorsthathavehigh variability.Windandsolarpoweroutputcan varysignificantlybyminute,hour,andseasonduetodiurnaleffects,weatherpatterns, andinstantaneoussolaravailability.The minute-to-minuteandseasonalvariations ofpowerproducedfromphotovoltaicand windplantsareonthesameorderofmagnitudeastheaverageoutput.Second,theavailabilityofwindandsolarresourcesisalso poorlymatchedwiththelocationswhere theenergyisneeded.Forexample,while thereissignificantwindandsolarpowerpotentialinwestTexas,therearenomajorelectricityusersorurbancentersinthisarea. Thesetwochallengesimplythatforalternativeenergysourcestobecomecompetitive, additionalenergystorageandtransport mustbeintegratedwiththem.Ina decarbonizedenergyeconomy,theprincipal
energycarrierswilllikelyincludeelectricity andhydrogen.Hydrogenhastheadvantage thatitcanbeeasilystored,whileelectricity hastheadvantagethatitdoesnothaveto bereconvertedtobeusefulformost applications.
Hydrogenisacolorless,odorlessgasthat burnswithanear-invisibleflame.However, hydrogenisoftenreferredtobycolor.These “colors”colloquiallyrefertothewaythehydrogenisgeneratedresultinginarainbowof colors.Forthemostpart,turbomachinery thateitherutilizesortransportshydrogen doesn’tcarewhereandhowthehydrogen originated,butitisstillimportanttounderstandthebasicnomenclature.
Greenhydrogenisproducedwithoutany greenhousegasemissions.Itismadebyusing electricityfromrenewablesources,likephotovoltaicsorwindpower,toelectrolyzewater. Electrolyzersuseanelectrochemicalreaction tosplitwaterintoitscomponents,hydrogen, andoxygen.Bluehydrogenisproducedfrom naturalgasusingaprocessknownassteam reforming,wherenaturalgasandsteamreact toformhydrogen,butalsocarbondioxide.To makehydrogen“blue”thecarbondioxide mustbecapturedandsequestered.Ifthesame processisusedbutthecarbonisnotcaptured, wecallthegasgrayhydrogen.Blackand brownhydrogenaremadethroughpartialoxidationgasificationfromblackcoal(anthracite orbituminous)orbrowncoal(lignite).Thisis thetypeofhydrogenthatcreatesthelargest amountofenvironmentallydamagingbyproducts.
Red(alsoknownaspinkorpurple)hydrogenisgeneratedusingelectricityfromnuclearenergy.Justlikegreenhydrogen,an electrolysisprocessisused.Thedifference isthatnuclearwasteiscreatedasabyproductoftheseprocesses.Therearealso someideastousethehigh-temperaturereactorsoravailablesteam.Turquoise(orcyan) hydrogenismadebyaprocesscalled
methanepyrolysis.Theby-productissolid carbon.Dependingonthethermalprocess thatisusedforpyrolysis—forexample, whetheritcomesfromrenewablesources— andthecapabilitytostorethesolidcarbon permanently,thiscanbealow-orno-carbon process.Yellowhydrogenisproducedby electrolysisdirectlyfromsolarenergywithouttheintermediatestepofcreatingelectricity.Insomepublications,theterm“yellow” hydrogenisusedwhentheelectricityfor theelectrolysisprocesscomesfrommultiple sources,someofthemrenewable,someof themconventional.Finally,whitehydrogen isnaturallyoccurringgeologicalhydrogen. Thisisaprocessthatinvolvesdrillingahole inthegroundtogettohydrogen,withsome frackinginvolved;however,thereiscurrentlynolarge-scaleexploitationofthisrelativelyrareresource.
Asanenergycarrier,hydrogenoffersboth advantagesandchallengesrelativetoother technologies.Oneadvantageisthathydrogencanbesourcedfromfeedstocksthat areabundantinnature.Thethreemostcommonprocessestoproducehydrogenonan industrialscaleareelectrolysis,steam reforming,andgasificationpartialoxidation. Therearemanyvariantsoftheseprocesses, buttheirfundamentaldifferenceisthatfor steamreformingandpartialoxidation;ahydrocarbonisrequiredasfeedmaterial, whereaselectrolysissimplyrequiresanelectricpowersourceandwater.Assuch,electrolysisnaturallylendsitselftoapplications whereenergystorageistheprimaryobjectiveofhydrogenconversion.Ontheother hand,steamreformingfornaturalgasorpartialoxidationforcoalisacomplexchemical processthatconvertsafossilfuelintohydrogen,carbonmonoxide,andothercompoundsthroughanincompleteoxidation reactionthatallowsthehydrogentobeseparatedfromthemixture.Thistypeofhydrogenisnotnecessarilyenvironmentally
friendlyandrequirescarbonandotheremissionscontrolstominimizecarbondioxide emissionstotheatmosphere(akabluehydrogen).Nonetheless,becauseofthelow costoffossilfuelsandtherelativelylowcost oftheplantprocessequipment,morethan 98%ofallthehydrogenthatiscurrentlyproducedisderivedfromsteamreformingand partialoxidationoffossilfuels.
Hydrogencanalsobetransportedmore efficientlythanelectricityandinmany forms.Althoughhydrogenhasaveryhigh energydensityonapermassbasis,itsenergy densityonavolumetricbasisasacryogenic liquidorasagasattypicalpipelineconditionsisrelativelylow.Thislowvolumetric energydensityusuallyrequireshighpressuresforstorageandtransport,but compressinghydrogenisveryenergyintensiveduetoitslowmolecularweight.The petrochemicalindustryhasdecadesofexperiencewithpurehydrogenpipelinesinvariousgloballocationswithanetlengthofmore than1000kmatpressuresfrom17bar (250psi)to96bar(1400psi),butthepipeline diametersof200–350mm(8–14in.)aremuch smallerthantypicalnaturalgastransmission pipelines,sonotalltechnologiesaredirectly scalableortransferable.
Hydrogencanbeconsideredoneofa varietyofthermochemicaltechnologiesthat storeenergythroughthecreationofchemical bonds.Thesechemicalscanbestoredfor longdurationsandreleasethermalenergy throughareactionwhenpowerisneeded. Inadditiontopurehydrogen,thereare severalhydrogen-basedreactionsthatcan beusedtoconverthydrogenintootherforms forstorageortransport,akathe“Power-toX”approach.Theseadditionalreactionsrequiremoreenergyconversionstepsbutoffer potentialbenefitsintransport,storage,or eventualconversionbacktoheatorelectricity.Therearemanypotentialchemicalsconsideredforhydrogen-basedPower-to-X,
includingsyntheticnaturalgas,ammonia, methanol,andformicacid,amongothers.
Bothgreenhydrogensfromalternativeenergysourcesandbluehydrogenderived fromfossilfuelsplayasignificantrolein thedecarbonizedenergyeconomy.This bookdiscussesthevarioustypesofdynamic machinesthatarerequiredineachstageof thehydrogensupplysystem,theirdesign, operation,andsafetychallengesaswellas theirbasiceconomics.Thetopicscovered inthebookwereselectedtoprovideengineers,scientists,andpractitionersinterested intheequipmentrequiredforthehydrogen economywithacomprehensivetechnology andapplicationoverview.Eachchapter
providessufficientbackgroundmaterialto standaloneandcanbeusedonitsown,althoughanattemptwasmadetoavoidduplicationthroughoutthebook.
We,theeditors,areindebtedtothechapterauthors.Theyareallsubjectmatterexpertswhowereselectedfromthescientific andengineeringcommunitybasedontheir relevantcontributionstothefield.Theyrepresentabroadanddiverserangeofknowledgeandhavevolunteerednumerous hourstoprovidetheircontributions;we thankthemwholeheartedly!
KlausBrunandTimothyAllison ElliottGroup,SouthwestResearchInstitute
Acknowledgments WethankRachelPyle,DorotheaMartinez,andAndreaBarnettfortheirtirelesseffortsand assistancewhileputtingthisbooktogether.
1 Machineryintheenergyfuture RobertB.Laughlin
DepartmentofPhysics,StanfordUniversity,Stanford,CA,UnitedStates
Inthedistantfuture,humanbeingswillnotburncarbonoutofthegroundanymore,either becausetheyhavebannedthepracticeorbecausesupplieshaverunout.Thereissomeuncertaintyaboutthetimescaleforthistohappen,fortheuseoftheenergycontainedinthese fuelsisintertwinedwiththeverynatureofourcivilizationandiscorrespondinglyhardto reduce(Smil,2017).Thus,forexample,Egypt(see Fig.1.1),acountrywithalargepopulation andamplesolarresources,isstillcompletelydependentonfossilfuels(StatisticalReviewof WorldEnergy,2020).However,thelong-termoutcomeonthescaleofcenturiesisnotin doubt.Suppliesoffossilfuelsontheeartharefinite,andtheywilleventuallybeexhausted (AnEstimateofUndiscoveredConventionalOilandGasResourcesoftheWorld,2012; H € o € ok andTang,2013).
1.1Thehydrogeneconomy Thehydrogeneconomyisavisionofhowthingsmightworkinthisfuturetime( Rifkin, 2003 ; TheHydrogenEconomy:Opportunities,Costs,Barriers,andR&DNeeds,2004 ; Ball andWietschel,2009 ; BrandonandKurban,2017 ).Hydrogenmanufacturedfromnon-fossil energysourceswouldsupplantpresent-dayfluidfuelsbutotherwisebeusedsimilarly.As apracticalengineeringmatter,hydrogenthusproducedwouldbeaproxyfornaturalgas.It isthesimplestenergy-carryingsubstancetomanufacture,anditisenvironmentallybenign (TheFutureofHydrogen,2019 ).Thephysicsandchemistryofchemicalfuelsarealsoso elementarythatonecansaywithreasonablecon fidencethattherearenoalternativestohydrogenasaprimaryenergycarrierinthisdistantfuturetime.Thus,thereisgoodreasonto takethevisionseriouslyandanticipateafutureinwhichmanufacturedhydrogenhas displacedhydrocarbonsandcoalascivilization’scentralmassstoragemediumforenergy (HydrogenEnergyStorage:GridandTransportationServices,NREL/TP-5400-62518,2015; OptionsforProducingLow-CarbonHydrogenatScale,2018 ; HydrogeninElectricity’sFuture,R46436,2020).
FIG.1.1 LightsoftheNiledeltaatnight.In2010,whenthispicturewastaken,Egyptobtained96%ofitsenergy fromfossilfuels.In2019,thefractionwas95%(StatisticalReviewofWorldEnergy,2020). ImageCredit:EarthScience andRemoteSensingUnit,NASAJohnsonSpaceCenter,ISS025-E-9858.ThisimageisalsopostedatWikimediaCommons.
However,ahydrogeneconomyinthenearfuture,forexample,afewdecadesfromnow,is adifferentmatter,foritisblockedatthemomentbythelowcostoffossilfuels.Thiscostproblemiswidelydiscussed(PathtoHydrogenCompetitiveness:ACostPerspective,2020; HydrogenStrategy:EnablingaLow-CarbonEconomy,2020; vanRenssen,2020; Petersonetal., 2020; Collodietal.,2017; Christensen,2020; WestlakeandPellow,2019; Hydrogen:ARenewableEnergyPerspective,2019).Itseffectsareshownin Fig.1.2.Thereisaconsiderableand growingpoliticalmovementtooverrideitlegislativelyandforceatransitionawayfromfossil fuelsimmediately—thegroundsbeingthatcivilization’spresentCO2 emissionsarecausing lastingdamagetotheenvironment(ClimateChange2014:MitigationofClimateChange: WorkingGroupIIIContributiontotheIPCCFifthAssessmentReport,2015; Moore,2016; Rockstr € ometal.,2017; Walshetal.,2017; TowardaClimate-NeutralGermany,2020; Roelfsemaetal.,2020; Berners-Lee,2021; Gates,2021).Butthisiseasiersaidthandone.While thedamageinquestionisveryreal,soaretheeconomicforcesthatcauseit.Thesearedue fundamentallyto“us”,asopposedto“them”,sotheyarehardtolegislateaway (Schiermeier,2012; Robertsetal.,2021; Ramachandran,2021).
1.2Energysources Thecostdisparitybetweenhydrogenandhydrocarbonshasitsrootsinthesourcesofenergy thesefuelscontain.Inthecaseofhydrocarbons,thisenergywassuppliedbyancientbiological processes,anditisthereforeessentiallyfreeexceptforthecostsofdiscovery,mining,refining, anddistribution.Theselatterthensetthemarketpricesofthefuels.Theenergyinhydrogen fuels,bycontrast,mustbeobtainedfromothersources,andthesearedecidedlynotfree.Indeed
FIG.1.2 Worldconsumptionofprimaryenergyoverthelast3decadesbrokendownintosectors(StatisticalReviewofWorldEnergy,2020).Thenuclearandhydronumbersreportedarenotthenumberofjoulesactuallydelivered but1/0.405 ¼ 2.47timesthenumberofjoulesactuallydelivered(StatisticalReviewofWorldEnergy,2020).Thismeasuresthenumberofjoulesoffossilfuelthatwouldhavebeenburnedinpowerplantswith40.5%efficiencytogeneratethesameamountofelectricity.Thewindandsolarcontributionstorenewableenergyhavebeensimilarly inflated,butthebiofuelscontributionhasnot.Thenumberofwindandsolarjoulesactuallydeliveredin2019totaled 6.75 1018 J (StatisticalReviewofWorldEnergy,2020; Renewables2020:AnalysisandForecastto2025,2020).The numberofbiofueljoules(includingthosefromcornethanol)deliveredin2019was4.11 1018 J (StatisticalReview ofWorldEnergy,2020).Thedashedlineatthebottomisthetotalenergycontentofallthehydrogenproducedin theworld,asreportedbytheIEA,convertedattheLHVvalueof1.2 108 Jkg 1 (TheFutureofHydrogen,2019). ThisincludesbothpureH2 (about60%ofthetotal)andH2 mixedwithothergases,notablyCO.TheIEAreportsthat 95%ofthishydrogenismadefromfossilfuels,primarilynaturalgasandcoal(TheFutureofHydrogen,2019; HydrogenStrategy:EnablingaLow-CarbonEconomy,2020).ThetoppanelshowstheKeelingcurve,the CO2 concentrationoftheatmospheremeasuredonMaunaLoa,Hawaii(Friedlingsteinetal.,2020; Bruhwiler etal.,2021; Breweretal.,2019; Keeling,2006).ThisatmosphericCO2 accountsforroughlyhalfthecarbonmassof thefossilfuelsconsumedinthelowerpanel,therestpresumablygoingintotheoceans.
themarketpriceoftheenergyusedtomakehydrogennormallylies above thatsuppliedbyfossil fuelsbecauseanyothersituationwouldgeneratearbitrageopportunities(TheFutureofHydrogen,2019).Sinceenergyisconservedabsolutely,thehydrogenfuelcontainsnoenergybeyond whatwasconsumed(fromothersources)initsmanufacture.Theenergysuppliedbyhydrogen thushasapricedisadvantagevis-a ` -visenergysuppliedbyfossilfuelsthatisfundamental.
1.3Theroleofmachinery Theeconomicmilieuinwhichthetransitiontothehydrogeneconomymustoccurdictatesaspecialroleformachinery.Thegener ationofhydrogenischieflyamatterofchemistryand/orelectrochemistry,somechanicalconsiderationsarelargelyirrelevantforthat partoftheenergychain.Thisexcludesthetra nsportandmanagementofreactants,which arestandardpetrochemicalindustryactivities.Butinthere-conversionofhydrogen’s
FIG.1.3 Cutawayillustrationofahydrogen-capablegasturbine.CurrentNOx emissionrestrictionsrequirethese designstoburnamixtureofhydrogenandnaturalgas,withnomorethan30%hydrogenbyvolume(Inoueetal., 2018). ImageSource:MitsubishiPower.
storedenergytomotivepowerorelectricenergy,conventionalheatengineshaveanadvantagestemmingfromtheirlowcostandhighreliability( CostandPerformanceDatafor PowerGenerationTechnologies,2012).Theyalsofacilitatevastlyloweredcostsofpiping andstorageinfrastructureforthehydrogenfu el.Atleastatthebeginningofthetransition, whentheamountsofhydrogenarerelativelysmall,thereisnopracticalwaytotransmit hydrogenenergyoverlongdistancesotherthantoblendthehydrogenwithnaturalgas andsendthemixturethroughexistingpipelinestoexistinggasturbines( Melainaetal., 2013 ; PipelineHydrogen,2018; Isaac,2019; Pellegrinietal.,2020).Thereitisburnedinmachineseitherspeciallydesignedtohandlemixturesorretrofittedwithburnersthatcando so(Inoueetal.,2018; Goldmeer,2019 ; HydrogenGasTurbines,2020).Asshownin Fig.1.3,a hydrogen-capablegasturbineisnotsodifferentfromonethatburnsonlynaturalgas.
1.4Competitionwithelectrochemistry Hydrogenisuniqueamongmanufacturedfuelsofthefutureinbeingespeciallysuitedfor useinfuelcells(YacobucciandCurtright,2004; Breeze,2017; SørensenandSpazzafumo, 2018).Thereisthusanalternatehydrogeneconomyscenarioinwhichthehydrogenisnot blendedwithnaturalgasforburningingasturbinesbutinsteadpipedinpureformtopower stationsorvehiclesequippedwithfuelcells.Thiswouldhavetheimportanteffectofeliminatingvirtuallyallthermally-generatedairpollution,inparticularNOx
However,economicsgreatlydisadvantagesthissecondscenario,atleastfornow.Theunderlyingreasonisthatfuelcellsarefundamentallymechanicalenginestoo.Theirmoving partsworkatthemolecularlevelandnearertothethermodynamicreversibilitylimit,but theyusethesamephysicalprinciplestogenerateelectricityfromthehydrogenthatconventionalenginesdoandhavethesamepracticalissuesofthermalefficiency,wearandtear,fabricationcost,andmaintenancecost.Thereisatthemomentonlyonefull-size(50MW) hydrogenfuelcellpowerplantintheworld(Larson,2020; Hanwha,Doosanopenby-product
hydrogenfuelcellpowerplant,2020).Itsreportedcostandperformancefiguresaremuch inferiortothoseofacombined-cyclegasturbineplant(Hanwha,Doosanopenby-product hydrogenfuelcellpowerplant,2020; Kanuri,2012; vanRooijen,2006; PureCellModel400, 2018).Therearealsoissuesoflong-termmaintenancecostsoffuelcellplants,butthesewill notbeknownreliablyuntilaftermanyyearsofoperation.
1.5Ongoingissues Whilehydrogenisfunctionallyaproxyfornaturalgas,itisnotthesamethingasnatural gas,andithasspecialpropertiesthathavetobeaccommodatedifitgrowstodisplacefossil fuelsasamajorenergydeliveryvehicle.Themostimmediateofthese,suchasburnermodificationsofgasturbines,havealreadybeenworkedthroughtheengineeringandproduct designstages,andsoarereadytobeimplementednow(Inoueetal.,2018; Goldmeer, 2019; HydrogenGasTurbines,2020).Butothersthatwouldbeneededinlaterstagesaremore difficultandthesubjectofongoingresearchanddevelopment,asdiscussedfurtherinsubsequentchaptersofthisbook.Examplesinclude.
1. Hydrogenhasatendencytoinsinuateitselfintotheatomicstructureofmetalsand embrittlethem(LouthanJr.etal.,1972; SanMarchiandSomerday,2012; Robertsonetal., 2015; Lee,2016; Barreraetal.,2018; Martinetal.,2020).Thisproblemisalreadydealtwith intheworld’sexistinghydrogenpipelineinfrastructurebutnotinitsnaturalgaspiping andstoragesystemandnotgas-handlingcompressorsandpumps(Parfomak,2021).
2. Hydrogenhasanespeciallyhighflametemperaturewhenburningintheair,andthushas atendencytogenerateexcessiveNOx (WeilandandStrakey,2010).Thisproblemcanbe mitigatedbyleanburning,dilution,exhaustgasrecirculation,andothersimilarstrategies, butalloftheseinvolvetradeoffswiththermalefficiencyandflamestability(Ditaranto etal.,2020).NOx emissionlevelswithincurrentregulatorylimitshavebeenachievedin turbinesburningblendsofhydrogenandnaturalgaswithlessthan30%hydrogenby volumebutnotforturbinesburningpurehydrogen(Inoueetal.,2018; Goldmeer,2019; HydrogenGasTurbines,2020).Thisproblemremainsalsoforreciprocatingengines burningpurehydrogen(Hoekstraetal.,1996).
3. Hydrogen’ssmallmolecularweightmakesitdifficulttocompressusingturbocompressors (Schusteretal.,2020; Adametal.,2020; Brunetal.,2020; Wanner,2021).Thehighsoundspeed mandatesrotortipspeedsthatproducestressesbeyondtheabilityofpresent-daymaterialsto handle,andthelowmassputsaceilingonthecompressionratioperstage.Thepresent-day standardforpurehydrogenpipelinecompressorsisreciprocating(Wanner,2021).
4. Hydrogen’slowheatofcombustionmakesitsliquefactionlossesproblematic(Wanner, 2021; Connellyetal.,2019; OhligandDecker,2014).Withcurrentlyavailabletechnology, theenergyrequiredtocoolhydrogeninitiallyatstandardtemperatureandpressuretoits liquidstateisabout3.9 107 Jkg 1 (Wanner,2021; Connellyetal.,2019).Thisis33%ofthe hydrogen’sLHVenergycontentof1.2 108 Jkg 1.Nearlyallofthisliquefactionenergyis discardedaswasteheat.Thetheoreticalmaximumamountofenergyavailablefor extractioninthere-expansionprocessis1.56 107 Jkg 1 (Wanner,2021).
1.6Machineryintheenergyfuture Thehistoricalconsumptionsituationshownin Fig.1.2 tellsusthatthetransitiontoafossilfreeeconomyisacomplexeventthatisunfoldingslowly,notwithstandingeffortsofagreat manypeopletoretardthenegativeeffectsofCO2 buildupontheearth,andthatmayormay notadvancesignificantlyinourlifetimes.Timewilltell.Butwhenthetransitioneventually comes,asthefinitenessofgeologicresourcesrequiresittodo,hydrogenwillverylikelybe oneofitscentralcomponents,withmechanicalmachineryessentialtohydrogen’sfunction. Thisisso,amongotherreasons,becausethelawsofphysicsandeconomicsasweknowthem todaywillstillbeoperatinginthisdistanttime.
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