2026未来全球硅基光伏系统部署的原生与再生材料流研究报告

Task12PVSustainability

PVPS

PrimaryandSecondaryMaterialFlowsforthe

FutureGlobal

DeploymentofSilicon-basedPhotovoltaic

Systems

2026

ReportIEA-PVPST12-34:2026

Task12PVSustainabilityActivities一PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems

WhatisIEAPVPSTCP?

TheInternationalEnergyAgency(IEA),foundedin1974,isanautonomousbodywithintheframeworkoftheOrganizationforEconomicCooperationandDevelopment(OECD).TheTechnologyCollaborationProgramme(TCP)wascreatedwithabeliefthatthefutureofenergysecurityandsustainabilitystartswithglobalcollaboration.Theprogrammeismadeupof6000expertsacrossgovernment,academia,andindustrydedicatedtoadvancingcommonresearchandtheapplicationofspecificenergytechnologies.

TheIEAPhotovoItaicPowerSystemsProgramme(IEAPVPS)isoneoftheTCP’swithintheIEAandwasestabIishedin1993.Themissionoftheprogrammeisto“enhancetheinternationaIcoIIaborativeeffortswhichfaciIitatetheroIeofphotovoltaicsolarenergyasacornerstoneinthetransitiontosustainabIeenergysystems.”Inordertoachievethis,theProgramme’sparticipantshaveundertakenavarietyofjointresearchprojectsinPVpowersystemsappIications.TheoverallprogrammeisheadedbyanExecutiveCommittee,comprisedofonedelegatefromeachcountryororganisationmember,whichdesignatesdistinct6Tasks,’thatmayberesearchprojectsoractivityareas.

The28IEAPVPSparticipatingcountriesareAustralia,Austria,Belgium,Canada,China,Denmark,Finland,France,Germany,India,Israel,Italy,Japan,Korea,Lithuania,Malaysia,Morocco,theNetherlands,Norway,Portugal,SouthAfrica,Spain,Sweden,Switzerland,Thailand,Turkiye,theUnitedKingdomandtheUnitedStatesofAmerica.TheEuropeanCommission,SolarPowerEuropeandtheSolarEnergyResearchInstituteofSingaporearealsomembers.

Visitusat:

WhatisIEAPVPSTask12?

ThegoalofTask12istofosterinternationalcooperationandknowledgesharingonthesustainableaspectsofPVtechnology,emphasizingenvironmentalandsocialfactors.Itsmissionistoprovideessentialinformationtostakeholders,enhancingconsumerandpolicy-makerconfidenceinPVsystems,andtherebyacceleratingtheshifttowardssustainableenergy.TheobjectivesofTask12areto:(1)QuantifyPVeIectricity’senvironmentaIprofiIetoenhancesuppIychainsustainabilityandenablecomparisonswithotherenergytechnologies.(2)EnhancePVtechnologyandmaterialscircularitythroughnovelanalysis,legislativetracking,andtechnicalstandardsdevelopment.(3)InvestigatesynergiesbetweenPVsystemdeploymentanditsenvironmentalandecosystemimpacts.(4)Identifyandtacklebothrealandperceivedsocialandsocio-economicchallengestoPVmarketgrowth.(5)Shareanalyticalfindingswithtechnicalexperts,policymakers,andthepublic.

Task12isoperatedjointlybytheNationalLaboratoryoftheRockies(NLR)andTotalEnergies.SupportfromtheU.S.DepartmentofEnergyandTotalEnergiesisgratefullyacknowledged.

DISCLAIMER

TheIEAPVPSTCPisorganisedundertheauspicesoftheInternationalEnergyAgency(IEA)butisfunctionallyandlegallyautonomous.Views,findingsandpublicationsoftheIEAPVPSTCPdonotnecessarilyrepresenttheviewsorpoliciesoftheIEASecretariatoritsindividualmembercountries

COPYRIGHTSTATEMENT

Thiscontentmaybefreelyused,copiedandredistributed,providedappropriatecreditisgiven(pIeaserefertothe6SuggestedCitation’).

Theexceptionisthatsomelicensedimagesmaynotbecopied,asspecifiedintheindividualimagecaptions.

SUGGESTEDCITATION

Abdelbaky,M.,Xu,C.,Isabella,O.,Vogt,M.R.(2026).Heath,G.(Ed.),PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems(ReportNo.T12-34:2026).IEAPVPSTask12.DOI:10.69766/WQPE7074

INTERNATIONALENERGYAGENCY

PHOTOVOLTAICPOWERSYSTEMSPROGRAMME

PrimaryandSecondaryMaterialFlowsfor

theFutureGlobalDeploymentofSilicon-

basedPhotovoltaicSystems

IEAPVPS

Task12

PVSustainability

ReportIEA-PVPST12-34:2026

September2026

ISBN:978-1-923734-13-5

DOI:10.69766/WQPE7074

Task12PVSustainabiltiyActivities-PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems

AUTHORS

MainAuthors

MohammadAbdelbaky,DelftUniversityofTechnology,TheNetherlandsChengjianXu,DelftUniversityofTechnology,TheNetherlands

OlindoIsabella,DelftUniversityofTechnology,TheNetherlandsMalteR.Vogt,DelftUniversityofTechnology,TheNetherlands

Editor

GarvinHeath,NationalLaboftheRockies,USA

TaskManagers

GarvinHeath,NationalLaboftheRockies,USA

EtienneDrahi,TotalEnergies,France

Task12PVSustainabiltiyActivities-PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems

5

TABLEOFCONTENTS

ListofFigures 6

Listoftables 7

Acknowledgements 9

Listofabbreviations 10

Executivesummary 12

1Introduction 15

2Materialsandmethods 19

2.1PVDeploymentScenarios 19

2.2PVtechnologydevelopments 20

2.3PVtechnologyfunctionallayerconfigurationsandtheunderlying

materialdemand 23

2.4Materialflowanalysismodel 25

2.5Sensitivityanalysis 26

2.6Resource-useassessment 28

3Resultsanddiscussion 30

3.1FuturedemandtrendsandrecyclingprospectsforPVmaterials 30

3.2Sensitivityanalysis 38

3.3Resource-useimpacts 42

4Conclusion 44

5Limitationsandfutureresearch 45

References 47

A.APPENDIX:StartingPVtechnologymaterialcomposition[2025] 54

B.APPENDIX:Additionalresource-useimpactresults 58

C.APPENDIX:Detailedresultsforthefutureannualend-of-lifePVsystem

outflows 59

D.APPENDIX:Additionalresultsforin-usestockandannualmaterialflows 61

E.APPENDIX:SensitivityanalysisresultsforthecumulativePVrawmaterial

demands 64

Task12PVSustainabiltiyActivities-PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems

6

LISTOFFIGURES

Figure1:Installedcapacityprojectionsforthedeploymentscenariospresentedinthisstudy,

includingtheIEAscenarioof29TWpby2050aslowPVdeployment[25],andtheLUT

scenarioof63TWpby2050ashighPVdeployment[26] 20

Figure2:AssumeddevelopmentsinmoduleefficiencyandmarketshareofthedifferentPV

technologies 21

Figure3:(a,b)materialbreakdownofin-usestockmassofglobalPVinstalledcapacity,(c,d)

breakdownofannualinflowmass,(e,f)breakdownofannualoutflowmass(millionmetrictons).

(a,c,e)correspondtothelowPVdeploymentscenario,(b,d,f)correspondtothehighPV

deploymentscenario 30

Figure4:Cohortsofin-usePVstock(TWp)byinstallationyearandremainingdeployment

years.(a)lowPVdeploymentscenario,(b)highPVdeploymentscenario.Theleftmostcolumn

representsannualnewinstallationsforeachinstallationyear,whilesubsequentvaluesineach

rowtrackthedeclineinremainingcapacityovertimeduetoend-of-lifeoutflows 32

Figure5:ForecastedcumulativeCudemandbyPVsystemcomponent(2025-2050).(a)

cumulativedemandformodule(cellinterconnections),inverters,&cables(b)cumulative

demandforcellmetallization 33

Figure6:ForecastedcumulativeAldemandbyPVsystemcomponent(2025-2050).(a)

cumulativedemandformodule(frame)&mountingstructure(b)cumulativedemandfor

inverter 34

Figure7:ForecastedannualinflowdemandandsecondarysupplyofPVrawmaterialsforthe

fivedeploymentscenarios.(a)annualgoldin-andout-flows,(b)indium,(c)silver,(d)tin,(e)

lead,(f)zinc,and(g)silicon 36

Figure8:SensitivityanalysisresultsofcumulativesilverandindiumdemandfromthePV

sector,2025-2050inktons.(a)X-axisisthe2050installedcapacityforeachofthefive

deploymentscenarios,Y-axisisthefixedvalueassumedforthemarketshareofsilverscreen

printingincellmetallization,remainingshareisallocatedtocopperscreenprintingandcopper

platingasdescribedinsection2.2,Z-axisisthecumulativesilverdemandinktons.(b)X-axis

isthefixedvalueassumedforthemarketshareofITO-basedtechnologies(SHJ,IBC-SHJ,&

Pvk-Si-tandem),remainingshareisallocatedTOPCon&IBC-TOPConasdescribedinsection

2.2,Z-axisisthecumulativeindiumdemandinktons.Thereserveandresourceestimateis

representedbyahorizontalplaneat50ktons,whichintersectswiththecumulativedemand

plane,andvalueslessthan50ktonsareprojectedonthegreenplane 40

Figure9:SensitivityanalysisresultsofcumulativesilicondemandfromthePVsector,2025-

2050inMtons.(a)X-axisisthe2050installedcapacityforeachofthefivedeployment

scenarios,Y-axisisthefixedvalueassumedforthewaferthickness,Z-axisisthecumulative

silicondemandinMtons.(b)X-axisisthe2050installedcapacityforeachofthefive

deploymentscenarios,Y-axisisthefixedvalueassumedforthekerflosses,Z-axisisthe

cumulativesilicondemandinMtons 41

7

FigureC-1:CohortsofAnnualEnd-of-LifeOutflowsinGWpbyInstallationandRetirement

Years-LowDeploymentScenario 59

FigureC-2:CohortsofEnd-of-LifePVsystemoutflows(GWp)byinstallationandretirement

Years-HighDeploymentScenario 60

FigureD-1:PVrawmaterialscontentinthein-usestockforthefivedeploymentscenarios.(a)

gold,(b)indium,(c)silver,(d)tin,(e)lead,(f)zinc,and(g)silicon 61

FigureD-2:ForecastedannualinflowdemandandsecondarysupplyofPVrawmaterialsfor

thefivedeploymentscenarios.(a)copper,(b)aluminum 62

FigureD-3:PVrawmaterialscontentinthein-usestockforthefivedeploymentscenarios.(a)

copper,(b)aluminum 62

FigureD-4:Cumulativedemand(inktons/Mtons)andcumulativesecondarysupply(asa%of

cumulativedemand)ofPVrawmaterialsforthefivedeploymentscenarios.(a)silicon,(b)

aluminum,(c)copper,(d)silver,(e)zinc,(f)gold,(g)indium,(h)tin,and(i)lead 63

FigureE-1:Cumulativesilverdemand(2025-2050)asfunctionofsilverpasteloadingand

futureinstalledcapacity

64

FigureE-1:Cumulativesilverdemand(2025-2050)asfunctionofsilverpasteloadingand

futureinstalledcapacity 64

FigureE-2:Cumulativealuminumdemand(2025-2050)asfunctionofthemarketshareof

aluminummoduleframesandfutureinstalledcapacity 64

FigureE-3:Cumulativecopperdemand(2025-2050)asfunctionofthelearningcurveof

invertersandcablingandfutureinstalledcapacity 65

LISTOFTABLES

Table2-1:Overviewofthefunctionallayersandcorrespondingthicknessassumptionsper

siliconPVcelltechnology 23

Table2-2:Uncertaintiesconsideredinthesensitivityanalysisandthevaluesassumed 27

Table3-1:Resource-useindicatorsforthePVsectorrawmaterialdemandsbetween2025and

2050inMtonsSbeq.,consideringtheentirecumulativedemand(2025-2050) 43

TableA-1:Materialbreakdowninkilogramsfora1kWpmonofacialPVsystem,BOS

componentsaremodeledbasedonthemarketshareofresidentialandutilityinstallations

assumed 54

TableA-2:Materialbreakdowninkilogramsfora1kWpbifacialPVsystem,BOScomponents

aremodeledbasedonthemarketshareofresidentialandutilityinstallationsassumed 56

8

TableB-1:Resource-useindicatorsforthePVsectorrawmaterialdemandsbetween2025

and2050inMtonsSbeq.,consideringthenetprimarydemand(2025-2050)[subtracting

materialcontentinthecumulativeoutflowPVwastestream(2025-2050)]

58

9

ACKNOWLEDGEMENTS

WesincerelythankMárioAliangandPenghuiXiefortheirmaster’sthesiswork,whichprovidedvaluableinputtothisreport,andNithinVakeriPerunthottathilfortheircarefulreviewandconstructivefeedbackthathelpedrefinetheresults.ThisreportalsobenefitedfromvaluablefeedbackfromIEA-PVPSTask12members,whichfurtherstrengthenedthecontentofthisreport.WealsothankfinancialsupportfromtheBURSTproject,thathasreceivedfundingfromtheEuropeanUnion'sHorizonEuropeProgrammeunderGANo.101146684.

Task12PVSustainabiltiyActivities-PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems

10

LISTOFABBREVIATIONS

ADPUR

AbioticDepletionPotential,ultimatereserves

ADPER

AbioticDepletionPotential,economicreserves

Al

Aluminum

Al-BSF

Aluminumbacksurfacefield

BiLSTM

BidirectionalLongShort-TermMemory

BOS

Balance-of-system

CAGR

Compoundannualgrowthrate

Cu

Copper

c-Si

Crystallinesilicon

dMFA

Dynamicmaterialflowanalysis

EoL

End-of-life

EJ

Exajoules

Gtons

Gigatons

GWp

Gigawatt-peak

Au

Gold

In

Indium

ITO

Indiumtinoxide

ESSENZ

IntegratedMethodtoAssessResource-UseEfficiencymethod

IBC

Interdigitatedbackcontact

IEA

InternationalEnergyAgency

IRENA

InternationalRenewableEnergyAgency

ITRPV

InternationalTechnologyRoadmapforPhotovoltaics

ktons

kilotons

kWp

Kilowatt-peak

LUT

Lappeenranta-LahtiUniversityofTechnology

Pb

Lead

MtonsSbeq.

Megatonsantimonyequivalents

Mtons

Millionmetrictons

mg

milligrams

NZE

NetZeroEmissionsby2050Scenario

OAT

One-at-a-time

Task12PVSustainabiltiyActivities-PrimaryandSecondaryMaterialFlowsfortheFutureGlobalDeploymentofSilicon-basedPhotovoltaicSystems

11

PERC

Passivatedemitterandrearcontact

Pvk-Si-

tandem

Perovskite-silicontandem

Si

Silicon

SHJ

Siliconheterojunctioncells

Ag

Silver

PV

Solarphotovoltaic

SOPURR

SurplusOrePotential,UltimateRecoverableResources

TWp

Terawatt-peak

Sn

Tin

TCO

Transparentconductiveoxide

TOPCon

Tunneloxidepassivatedcontact

Wp

Watt-peak

w%

weightpercent

Zn

Zinc

12

EXECUTIVESUMMARY

TheanticipatedexpansioninPVinstalledcapacitywillincreasedemandforrawmaterialsnecessaryformanufacturinganddeployment.Thisalignswithglobaldecarbonization scenariosandrecentresearchwhichidentifyrapidexpansionofrenewableenergycapacityas“thesinglelargestdriver”ofnear-termemissionsreductionsonpathwaystonet-zeroby2050 [1].Silicon-basedPVdominatesglobalproduction(~98%),consequentlythisreportfocusesonSiliconbasedPV[2],[3],[4].Nevertheless,anumberofsilicon-basedPVmaterialsareclassifiedas“critical”inseveralmajoreconomiesbasedonregion-specificassessmentsofpotentialsupplydisruptionsandeconomicimportance[5].RecentestimatessuggestthatannualPVdemandcouldpeakatapproximately40%ofglobalsiliconproduction,44%ofsilver,25%ofcopper[6],whichposespotentialconstraintstolarge-scalePVdeployment.Despitegrowingattentiontothistopicintheliterature,therearetwocleargapsinunderstanding:(1)evaluatingrawmaterialdemandatthesystemlevelwithrespecttoongoingtechnological shifts,and(2)accountingfordynamicreductionsinmaterialintensitythatarealready reshapingthescaleoffuturedemand.

Thisreportpresentsadynamicmaterialflowanalysis(dMFA)modelforestimatingfuturesilicon-basedPVsystem-relatedrawmaterialdemand,secondarysupply,andin-usestock,withdeploymentscenariosrangingfrom29TWpto75TWpofinstalledglobalsilicon-basedPVcapacityby2050.Inthisreport,6secondarysuppIy’referstothemateriaIcontentofmodeIedEoLPVoutflowsundertheassumedcollectionandrecoveryconditions.Unlessotherwisespecified,theseestimatesrepresenttheoreticalavailabilityinthewastestreamanddonotimplythatthematerialcanbefullyrecovered,purifiedtoPV-gradespecifications,orreintegratedintoPVmanufacturing.ThemodelassumesthatfuturePVdeploymentwillcontinuetobedominatedbysilicon-PV.Withinthat,itaccountsforexpectedshiftsinthefuturemarketshareofincludingaluminumbacksurfacefield(Al-BSF),mainlyforsalespriorto2025,aswellaspassivatedemitterandrearcontact(PERC),tunneloxidepassivatedcontact(TOPCon),siliconheterojunction(SHJ),interdigitatedbackcontact(IBC),andperovskite-silicon-basedtandem(Pvk-Si-tandem)technologies.Moreover,themodelaccountsforreductionsinmaterialintensityasmanufacturingprocessesbecomemoreefficient,performanceparametersimprove,andmaterialsaresubstitutedorphasedout.Theanalysisfocusesonninekeyelements:aluminum,copper,indium,lead,silicon,silver,gold,tin,andzinc.ResultsforotherPVmaterialsareaggregatedatthecomponentlevel.

Thecelllevelismodeledbasedonthesiliconwaferandtheadditionalfunctionallayerscommontocommercialcells,whilethemodulelevelincludesfrontandbackglass,coppercellinterconnections,aswellasanaluminumframe.Atthesystemlevel,asimplifiedbillofmaterialsisappliedforbalance-of-systemcomponentstorepresentaveragematerialrequirementsperinstalledcapacity,withoutdistinguishingbetweendifferentinverterconfigurationsorcablelayouts.Systemcomponentsexcludedfromtheanalysis,includingfoundations,floatingstructures,controlsystems,andbatterystorage,arediscussedfurtherinthelimitationssection.Thisstudyassumedfullcollectionand100%recyclingefficiencyforthefuturewastestreamgeneratedtoprovideatheoreticalupper-boundestimateoftotalrecycledmaterialmassfromretiredPVsystems.Asensitivityanalysisisperformedtodeterminetheimpactofuncertainfuturedeploymentscaleandothertechnologicalfactorsonthesilicon-basedPVsectordemandforkeymaterials.Finally,theprojectedmaterialdemandsoftheglobalsilicon-basedPVsectorarethenevaluatedintermsofresourcedepletionusingtheAbioticDepletionPotential,ultimatereserves(ADPUR)method,economicscarcityusingtheAbioticDepletionPotential,economicreserves(ADPER)method,resourcequalitywiththe

13

SurplusOrePotential,UltimateRecoverableResources(SOPURR)method,andresourcecriticalitywiththeIntegratedMethodtoAssessResource-UseEfficiency(ESSENZ)method.

AccordingtothedMFAmodelresults,theglobalsilicon-basedPVsectorisprojectedtoconsumebetween145and280millionmetrictonsofcoppercumulativelybetween2025to2050,dependingonthescaleoffuturedeployment.Thisdemandisprimarilydrivenbycables(75w%)andinverter(13w%)components.Foraluminum,thecumulativedemandfrom2025to2050isprojectedtorangefrom510to1100millionmetrictons.Mountingstructuresaccountforaround70w%ofdemandonaverage,withtheirshareincreasingfrom66w%in2025to72w%by2050.Theshareofaluminumdemandduetomoduleframesisexpectedtodeclinefrom29%to23%between2025and2050duetothegradualadoptionofframelessmoduledesigns.Forsilicon,cumulative2025-2050demandisprojectedtorangefrom60to120millionmetrictonsofsolar-gradesilicon,withmorethan20%oftheinputsiliconlostduringwaferslicing.Forsilver,thecumulative2025-2050demandisexpectedtorangebetween100000and200000metrictons,stronglydependentonthefuturemarketshareofcoppermetallizationandsilverpasteloading.Thecumulative2025-2050indiumdemandisexpectedtorangebetween60000and160000metrictons,stronglydependentonthefuturemarketshareofITO-basedtechnologies.Tindemandcomesprimarilyfromsolderalloys,withaminorcontributionfromITOlayers,andmayrangefrom1-3millionmetrictons.

TheresultsshowthatcopperisthePVmaterialwithpotentiallythebiggestbottleneckinprimarysupplyforfuturesectordemand.CopperdemandbythePVsectorwillpeakinthemid-2040sat7-15milliontonsperyear,equivalentto30w%-65w%ofthecurrentannualglobalmineproduction[7].Previousstudiesshowthatnotallcountriesprioritizeminecapacityexpansion,anddespitecopperminingcapacitygrowingata3%CAGR,asupplygapof10.5-11.5millionmetrictonsisprojectedby2035[8],[9].Peakannualdemandforsolar-gradesiliconmayrangebetween3and6millionmetrictonsby2040,againstcurrentglobalcapacityofabout3millionmetrictons[10].However,continuedovercapacityinChinaandcapacityadditionsfromprojectpipelinessuggestthatsupplyconstraintsmaybelesssevere[11],[12].Forsilver,2025-2050cumulativedemandrepresentsroughly15w%-30w%ofcurrentglobalreserveestimate[7],whileannualuseinPVcellsisexpectedtopeakat9000metrictons,eveninhigh-deploymentscenarios.Thisisonlyaslightincreaseoverthe8600metrictonsestimatedfor2024shipments[13].Tincumulativedemandbetween2025and2050couldamountto30w%-64w%oftheestimatedglobalSnreservesreportedfor2024[7],dependingonthedeploymentscenario.Foralldeploymentscenarios,cumulative2025-2050indiumdemandisprojectedtosurpassthemostrecentglobalreserveandresourceestimateof50000metrictons(2009data[14],duetolackofamorerecentauthoritativeestimate)bythemid-2040s.Nonetheless,reserveestimatesandmineproductionfiguresevolveovertime,andcomparisonswithfuturedemandshouldbeinterpretedaccordingly.Basedonthelatestfiguresreplacementofindiumintransparentconductiveoxides(TCOs)isnecessaryforPVdeploymentatterawattperyearscale.Furthermore,alternativeTCOmaterialsarebeingtested,buttheyremainatalowtechnologyreadinesslevelduetovaryingstability,performance,andcostprofiles[15],[16],whichmaylimittheirmarketpenetrationandcontributiontoreductionstofutureindiumdemand.Continueddevelopmentofreplacementmaterial(s)forindiuminTCOs,orreductioninquantityusedpermodule,willbeimportantfortheindiumconsumingpartsofthePVindustry.

From2025to2050,themassofmaterialsconsideredhereinfromdecommissionedPVsystemsisexpectedtoequal15-20%ofthetotaldemandforthosesamematerialsoverthatperiod.Thislimitedpotentialforclosed-looprecyclingispartlyattributedtolongproductlifetime,whichdelaystheavailabilityofrecyclablematerial,inadditiontothepurityofrecoveredmaterials[17].However,exceptionsforthistrendareindiumandsilver.Forindium,the

14

relativelylatecommercializationandtheexpectedlargefuturemarketshareofITO-basedtechnologiesindicatethatmorethan90%ofcumulativedemandwillremaininin-usestockby2050,withthewastestreamcontributingonlytheremainder.Totalsilvermassinfuturesilicon-basedPVwastemaysupply30-45w%ofthecumulativedemandbetween2025and2050.

Basedontheprojectedcumulativerawmaterialdemandsduringthetimeframeofthisstudy,theADPURmethodidentifiesgoldusedininvertersasthelargestcontributortoresourcedepletionimpacts(56%),followedbycopper(33%)usedmostlyincables,andsilver(9%)usedincells.Hypothetically,100%closed-looprecyclingcouldreduceADPURimpactsby25%and17%underlowandhighdeploymentscenarios,respectively.TheESSENZmethodidentifiesindiumasthemaindriverofcriticalityimpacts(75%)duetolimitedreservesandconcentrationofglobalrefiningcapacity,followedbytin(9%)andsilver(6%).Hypothetical100%closed-looprecyclingmaypotentiallyreduceoverallcriticalityimpactsby10%atmost,whileincreasingtherelativecontributionofindiumtotheESSENZscoreto79%asitstotalmassinfuturesilicon-basedPVwastedoesnotmatchtherapidlygrowingdemand.

Thematerialconstraintsidentifiedinthisstudyarepresentedatatimeofrapidmarketexpansion.GlobalPVmodulepricesreachedhistoriclowsin2024-2025[18],whichaccelerateddeploymentbeyondearlierInternationalEnergyAgencyandBloombergNEFforecasts[19].Meanwhile,theEUCriticalRawMaterialsAct[20],theUSInflationReductionAct[21],andIndia'sProductionLinkedIncentiveschemeforsolarmanufacturing[22],togetherwithongoingtradetensions,areshapingmanufacturinginvestmentdecisionsandinfluencingwherePVmanufacturingcapacitywillbebuiltoverthecomingdecade[23].Nevertheless,thefindingsofthisstudyindicatethatmaterialefficiencyimprovementsandmaterialsubstitutionstrategiesshouldbeconsideredalongsideincentivesfordomesticproductionandprocessingwhendesigningpoliciestosupportPVdeployment.

15

1INTRODUCTION

Outlooksfromenergytransitionscenariospresentpromisingtrajectoriesforincreaseddeploymentofphotovoltaic(PV)systems.GlobalinstalledPVcapacityforelectricitygenerationmayexceed20terawatt-peak(TWp)by2050,asoutlinedintheNetZeroEmissionsby2050(NZE)fromtheInternationalEnergyAgency(IEA)andthe1.5°CpathwayfromtheInternationalRenewableEnergyAgency(IRENA)[24],[25].TheIEANZEscenariofurtherprojectsapproximately145exajoules(EJ)ofPV-generatedenergyallocatedtoforelectricityservicesandelectrifiedheatsupply(e.g.,heatpumps)by2050,withanadditional123EJusedfortheproductionoflow-emissionhydrogen-basedfuels.Higher2050deploymentprojectionshavebeenreportedintheliterature;forexample,Bogdanovetal.estimate63TWpofinstalledcapacity,assumingelectrificationof89%oftotalprimaryenergydemand(includingforheatingandwaterdesalination)[26],whileHaegeletal.envisionupto75TWpinstalledcapacity[27].ThescaleofPVdeploymentprojectedunderthesescenariosentailssignificantrawmaterialrequirements,whichdifferconsiderablyfromthoseofotherrenewableenergytechnologies.Forexample,whilePVandwindsharecommonbulkmaterialssuchassteel,concrete,aluminum,copper,andglass,theirintensitiesdiffer:windturbinesrequiresignificantlymoreconcreteands