【牛津能源研究所】2024正確測量低碳氫的碳強度對降低監(jiān)管風險的作用研究報告414mb

June

2024IESPaper:

ET37Howpropermeasurementoflo carbon ydogen’scarbon

intensity

can

re ucere lat ry

riskAlexBarnes,VisitingResearchFellow,

OIESThecontentsofthispaperaretheauthor’ssoleresponsibility.TheydonotnecessarilyrepresenttheviewsoftheOxfordInstituteforEnergyStudiesoranyofitsmembers.1Thecontentsofthispaerretheuthor’solresposibility.yotecessarilrepresenttheviewsit

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yCopyright?2024OxfordInstituteforEnergy

Studies(RegisteredCharity,No.

286084)Thispublicationmaybereproducedinpartforeducationalornon-profitpurposeswithoutspecialpermissionfromthecopyrightholder,providedacknowledgementofthesourceismade.NouseofthispublicationmaybemadeforresaleorforanyothercommercialpurposewhatsoeverwithoutpriorpermissioninwritingfromtheOxfordInstituteforEnergy

Studies.ISBN978-1-

8467-247-8ummaryHy

rogen

wi a

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endenttheconmywhicarenotesilyelectfied.Hydrgeoftharonrolmth

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hydrog orfosfuels.

ItInthispaperlowcarbonhydrogenisdefinedashydrogenwithasignificantlylowercarbonintensitythanhydrogenbasedonfossilfuelswithoutCCS.SimilarlylowcarbonelectricityisdefinedaselectricitysignificantlylowercarbonintensitythanelectricitybasedonfossilfuelswithoutCCS.Lowcarbonelectricitythereforeincludesrenewables(e.g.wind,solar,hydro,geothermal,biomass),nuclearandfossilfuelgenerationwith

CCS.2Thecontentsofthispaerretheuthor’solresposibility.yotecessarilrepresenttheviewsit

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ygri

a hydr encarbo

int

nsitie meet

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missionsoem

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eission

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intensitL

O andsletrol

serictt

mporalenabere ctiwill

havecor

elatiules

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sitof

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nhydroe,nabl

a

si lifi

atio fthe le h

hr cesrgutor

uncintyforroctsboth

intermsof

u

derst ing

the

curre rle andheri offutu rulecha

ges.Propercomarionoflowcarbonh

drog

n oduc

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in iffeet

countrs

requirescom

onmetho

ology

fo

s

r

g

missi

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om

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ed

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ewith

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ofHydrgnThiswldstillbleoiestoseteirwncarbointensitytresold,thelevelofsupporttorovieandhotoproide

it.Theeasond’etroraronhydroesattwillassistormetsnhireffortsecarnietheeconoies.Thisntuependsonthcotffectenesoflwcarbonhrogenioings.Iflowarbodgfidontrteiriskslosigtgvemntpponees

fco

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nies

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c

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rkets

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ingbltcanesextraties

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ork

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costs, oj t

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ple tio btr

lesss

GHG

e s

ion G

vern nts

ca nable

mar

e o

b gow

theesproeraccountingflowarbonhdrogen’scrniteny,alonsicmmonccountigsndardsandnmnclatur.Onlyriorsaccuntigstads,bkeupyflxiblgvernmetsuportbasdcarbiteny,illeableestentinlocaonyonsly,infrastrucureanddemadhereitakesthmtsens-bothfinacllyndenronmenta

y.Ricks,Xu,Jenkins(2023)‘Minimizingemissionsfromgrid-basedhydrogenproductionintheUnitedStates.’EnvironmentalResearchLetters.WilsonRicksetal2023Environ.Res.Lett.18

0140253Ruhnau,Schiele(2023)‘Flexiblegreenhydrogen:Theeffectofrelaxingsimultaneityrequirementsonprojectdesign,economics,andpowersectoremissions.’Energy

Policy.4Sorrenti,Zheng,Singlitico,You(2023)‘Low-carbonandcost-efficienthydrogenoptimisationthroughagridconnectedelectrolyser:ThecaseofGreenLabSkive.’RenewableandSustainableEnergy

Reviews.3Thecontentsofthispaerretheuthor’solresposibility.yotecessarilrepresenttheviewsit

Members.ofthOorInstitutfornergyStudieora

yontentsSummary

iiContents

vFigures

vTables

v1. Introduction

12. Challengesforstakeholders

12.1Policymakers

2.2Hydrogenproducers

2.3Hydrogenusers

3. Clarifyingthenomenclature83.1Thecolourof

hydrogen3.2Clean,renewableorlowcarbonhydrogen

4. Measuringhydrogen’scarbonintensity

114.1SystemBoundaryandScopeEmissions.

114.2Emissionscalculationmethodology

134.3Measuringupstreamemissions

134.4Measuringhydrogenproductionemissions

14Measuringthecarbonintensityofelectricityusedinelectrolysis.

14Temporalcorrelation,additionalityandgeographiccorrelation175.2Comparinghourlyandmonthlytemporalcorrelation175.3Comparinghourlycorrelationwithaveragesystem

matching19Interactionofelectrolyserefficiencywithtemporalcorrelation

20Impactofloosertemporalcorrelationrulesonfuturerenewableenergyneeds235.6Comparinghourly,weeklyandannualtemporalcorrelation245.7Interactionwiththegrid

286.Reducingregulatoryriskforlowcarbonhydrogen317.Conclusions

35FiguresFigure1:Wrngtemp

ratures

f selectedrenewableheattechnologiesand

temperaturerequirmntofsectedindustris

3Figure2:Esti

ation

of newableelectricitygenerationneededfor1MWhbyenergyservicesandbtransf ationpatha

..

...

...Figure3:Illutrationoftrade-offsbetweenusinglowcarbonhydrogenorothertechnologies

todecarose

..

...

..

5Figure4:IllustrationofsystemboundaryandScopeEmissionsforhydrogen

1Figure5:EU27andUKGridElectricityCarbonFootprint2021

5Figure6:ComparisonofEU27andUKgenerationmixandelectricitygridcarbonintensity

5Figur

7: omparon

of

EU andUK2021gridelectricityandelectrolytichydrogencarbonintensibased monthlycor

el

tion

Figure

8: omarisoofU27ad

UK

2 1electrolytichydrogencarbonintensitybasedon

monthcorrelFigurecarboi and

fossil carbninenty..

...

9:Comprisonofcaronelectrlyserrunnghoursundersystemmatchingand

hydrogeniensityusinhurlyteporalcorretion...

...

04Thecontentsofthispaerretheuthor’solresposibility.yotecessarilrepresenttheviewsit

Members.ofthOorInstitutfornergyStudieora

yigure10:Impactofelectrolyserefficiencyonhydrogencarbonintensitybyselectedcountry

1Figure11:Additionalcarbonintensitybycountryandelectrolyserefficiency

2Figure12:ZerocarbonelectricityrequiredtoensurecarbonneutralhydrogenusingDAC

4Figure13:GridbasedhydrogenemissionsunderdifferentscenariosinWesternUS

6Figure14:LCOHofgridbasedhydrogenunderdifferentscenariosinWesternUS

7Figure16:GreenLabSkiveCO2abatementcostsscenarios

15Thecontentsofthispaerretheuthor’solresposibility.yotecessarilrepresenttheviewsit

Members.ofthOorInstitutfornergyStudieora

yTablesTable1:Carbonintensityofdifferenthydrogenproductionpathways

2Table2:Comparisonofdifferenthydrogendefinitions

9Table3:Electrolyserefficiencyratesandelectricityconsumptionperunitofhydrogenproduced

1Table4:LCOHandimpactonpowersectoremissionsunderdifferentscenariosinGermany

9Table5:ComparisonofLCOHandemissionsreductionsunderdifferentscenariosinGermany9Table6:ComparingHydrogenCarbonIntensityandLCOHscenariosforGreenLabSkive

01.

IntroductionInrecentyearstherehasbeenanincreasingfocusontheuseofhydrogenwithalowcarbonintensity(‘low

carbon

hydrogen’)

as

a

means

of

decarbonising

sectors

of

the

economy

which

are

not

easilyelectrifie Hydrogepoducdviaectrysis

islr,andthr

boringvaablereneableroblmsssciatd

withelectricity neratedintermittetenea

ehydrogn

iwindolct

cil fininenratiprces

,lsoseenaecomi

g.

T

e isalreadinhe nufac

uawy

feo

tifafch

micydr

ge

mar

t

ereand

fe

ti rs.

H ev

rihcarboint

ntyadthrefe

not

sui leas

ausdinthl ish

da

bonisith vd y.5

Issentilodi

eiatbetenxti

gvirtuallmeashig

cni

tensityipdueddoect

fydr ec

rbons re

oregen.

Thcaoi

tnsty

ofl arbonh

drogennprodctionpathayndthenputsue

.can

lso

va considrablydeLowc

rbon

hydr ensa

mandlond

gns(buty

o(G )

emi

io

s.

Lo

c

r

nso

gonment

inerv tnos

men a ansnotte

o

ly ean to

r ueGreenoseGass e

exp iisuired

tmetgdcaronistion

tan

t s

l e t nenddnco

ra o nd tusahs comp

e ith

opae,wayofist

gfosilfu

lsndother e s

ofant

on rehtweri

iss.Locaroydrognherforarbnisao.Governntswill

temsco-effeivde

rnisa

it

e s

of

ydrog ,

blsois

carbolow r

o

h roew

l

r uoldothiif

they

kn ot

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for

ac

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drogen.

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inglowc

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en subject

to

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t)

an ncrtai

tyTherequimetforpottiallyhighle(e.g.confsingor

difrnmentspptornterventmeanofreulatyisk(.gchangesineelsrntrulesidiffrentjurisdictin).

Thiper

exami sthecalleges

facingstakeholders

with

regards

to

understanding

hydrogen’s

carbon

intensity;

the

confusing

nomenclatureappied

tcanharisk

canlo

carbon dro n;ntheim

act

th differen pro

ches

to easuncarbnintensityydrog costs

an

its

act

al

car

on

i

tensity.

t

then

prop

s

s

ways

in hichr

gulatoryr

duced.2.Challengesfor

stakeholdersGovernmhyrogebeeasilyal

ngsidt prducrs

nd

sers lhaveaninterst

nclea

ro

it bility

oointe

siulatoryfraeworkcrbiseseooflowcaron

hrlowarbonwiccnnotogni

keAsecefololtrifdwhoitscostreativ

tocarbydroenestabonlectricitythethothrdecarbo

satnsoluonsanduren

unabatd

fossilf l

se.Policy

makersPolicymakersfacetwokeychallengesconcerninglowcarbon

hydrogen:Ithighcotcomparedtocurrenthydrogenproductionandcomparedtothefossilfuelsitaimsto

epl e.Itscarbonintensityandhenceitsabilitytocontributetodecarbonisation

targets.low

c onhdognde

endingTheIEA

reporranofosfloc on.as

d021

ceAfuels

(nral sor ngcl

guot

s

a neof.0sifi

at )

with.0S

/k1.to

3.6nproductioohydg

n/kgfor

fpathaandas

d

o

ssililful

asedhydrgenwit

C,and3.–2UD/kg

forel trolysiusing

loeisonelecticit

.6Decarbonisingexistinghydrogenuseshouldbearelativelyeasypolicygoalasdemandforthehydrogenalreadyexists,andthereforedoesnotrequirethesamedegreeofchangeascompanieswhichwillneedtoswitchfromfossilfuelsto

hydrogen.6IEA(2023),GlobalHydrogenReview2023,IEA,Paris,Licence:CCBY4.0.Pages88to

89.1Thecontentsofthispaerretheuthors’olresposibility.yotecessarilrepresenttheviewsit

Members.ofthOorInstitutfornergyStudieora

yheresaloawib

low

a

n deofnatralas,

corangeocarbonntrea

issi

sornuclerfuels.

Bnsitiesfordiffenthdrognssciedith

np

s

u aed

on

IE

figu

es7

th

se

erouctionpatwas.Thefiguresheroduinnrnrtatinumarisedintheable

below:Table1:Carbonintensityofdifferenthydrogenproduction

pathwaysRangeofcarbonintensity

(kgCO2e/kgH2SteamMethaneReformingwithout

CCS10–

13Coalgasificationwithout

CCS22-26SteamMethaneReformingwith

CCS*1.5–

6.2Coalgasificationwith

CCS*2.6–

6.3Electrolysisfromgrid-based

electricity0.5*–

24.0***Nuclear

electricity0.1–

0.3*Assumes93%capture

rate**BasedonSwedishgridcarbonintensityof10g

CO2e/kWh.***Basedonglobalaveragecarbonintensityof460gCO2e/kWh.Ingridswithcarbonintensityabovetheglobalaveragethecarbonintensityofhydrogenwillbe

higher.enti

ns

o

support

low

c

rb

n

hydro

en

nclud andatytrgetssuchasthe

EUGovernmeninterequirementthat(Renewable

Fue2 o droge us

d

i i

dustryof oBiological

Origi

- FNBOs,

t03 s

based rene

abl ectrityUKusidiesfor‘lowcarbon

hydrogen’undertheHydrogenProductionBusinessModel,ortheUS45Vtaxcreditsfor‘cleanhydrogen’undertheInflationReduction

Act.Theividi

glinebetwee

el

ctrificati anlow

arbon

h rogen

as

a eans

of

de rboniatiois

notlogirolvinndhrremscnsirbeunctntyabouthowmchsendyhichectrs.IRNAnotsthata‘rangeofoptionstoproducehighiactcit

(wit

resista e,infrred,iduction,microwve

ancle cut

T hhydrgenwlbetemp

at

e

aexists

a

d y

bdiffer tedu

em

e

ener

efficient

han

he

burning

of

green

hydrogen’.8

Fi

repplictionsandtheirheatrequirementscomparedtodiffernt

soulasmheating)b

o mp

ess

of ergy.Ibid.8IRENA(2022)Greenhydrogenforindustry.Aguidetopolicymaking.Page

12.2Thecontentsofthispaerretheuthors’olresposibility.yotecessarilrepresenttheviewsit

Members.ofthOorInstitutfornergyStudieora

yFigure1:Workingtemperaturesforselectedrenewableheattechnologiesandtemperaturerequirementofselected

industriesSource:IRENA(2022),Greenhydrogenforindustry:Aguidetopolicymaking,InternationalRenewablenergyAgency,AbuDhabi.Figure1.3Workingtemperaturesforselectedrenewableheattechnologiesandtemperaturerequirementofselected

industries.Hydrogenialsnasameansstorinsulusreneableeletricituilitisrequred.Oviouscompetitsortisluumpydro9nbaties,wherutilityorsoldca.OtherpotntialcoptitiludthrmaloragAllhecetgthnolishavtadva

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high.10IRENA(2022)Greenhydrogenforindustry.Aguidetopolicymaking.Page

13.3Thecontentsofthispaerretheuthors’olresposibility.yotecessarilrepresenttheviewsit

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y1“CumulativecarbonemissionsuntilthetimeofreachingnetzeroCO2emissionsandthelevelof

greenhousegasemissionreductionsthisdecadelargelydeterminewhetherwarmingcanbelimitedto1.5°Cor2°C(highconfidence)...IftheannualIftheannualCO2emissionsbetween2020–2030stayed,onaverage,atthesamelevelas2019,theresultingcumulativeemissionswouldalmostexhausttheremainingcarbonbudgetfor1.5°C(50%),anddepletemorethanathirdoftheremainingcarbonbudgetfor2°C(67%)”IPCC,2023:SummaryforPolicymakers.In:ClimateChange2023:SynthesisReport.ContributionofWorkingGroupsI,IIandIIItotheSixthAssessmentReportoftheIntergovernmentalPanelonClimateChange[CoreWritingTeam,H.LeeandJ.Romero(eds.)].IPCC,Geneva,Switzerland,pp.1-34,doi:10.59327/IPCC/AR6-9789291691647.001.ParagraphsB.5andB.5.312Ibid.ParagraphB.7.“Ifwarmingexceedsaspecifiedlevelsuchas1.5°C,itcouldgraduallybereducedagainbyachievingandsustainingnetnegativeglobalCO2emissions.Thiswouldrequireadditionaldeploymentofcarbondioxideremoval,compared

topathwayswithoutovershoot,leadingtogreaterfeasibilityandsustainability

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