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SustainabilityofPVSystemDuration:9/1/2014–8/30/2017

Total:~$250,000PrincipalInvestigator:JiquanChen,Email:jqchen@msu.edu

Graduatestudents:AngelaFan,SusieWuOBJECTIVESResearchersfromMichiganStateUniversitywillcontinueworkingwithallotherresearchersontheSEPteamwhileleadingtheresearchcomponentofThrust2(SustainabilityAssessmentoftheNewPVTechnologyandProduction).FundsarerequestedtosupporttwodoctoralstudentsattheDepartmentofGeography.Theobjectiveistoexplorethesustainabilityofthematerials,cellcomponents,andmanufacturingprocessesproposedandstudiedinThrust1throughLCSAoftheenvironmental,economic,andsociopoliticalmeasuresofalternativePVoptions.Wehypothesizethattrade-offsamongtheoptionsofsustainabilityaspectsmaybeoff-balanceorappeartocompeteovershorttimelinesbutmaypositivelycorrelateoverlongtimescales.Thesustainabilityassessmentwillprovideametricofindex,whichcanprovideimportantfeedbackforThrust1.Twospecifictasksare:Task1:DevelopmentofdynamicscenariosToassessthesustainabilityofPVtechnology,wewillmodelalternativefuturestates,suggestingthatmultiplescenariosneedtobedevelopedtorepresentpossibleandconsistentalternativestotheproposedPVtechnologysystem.Inourapproach,wetreatscenariodevelopmentasamajorresearchtask(vs.asetofpre-definedscenarios)thatwillbereiterativelymodifiedbasedontheLCSAoutput(Task2).

Task2.IntegratedassessmentmodelsviaSEMThedatabasedevelopedaboveisintricate.Amongthepromisingmethodsthathavebeenappliedtowardthiskindofcomplexsystemareneuralnetworks,pathanalysis,regressiontrees,SEM,andtraditionalmultivariateanalysis.124,125Forthistask,multiplevariantsoftheSEMwillbeusedtoassessthevulnerabilityanduncertaintiesofdifferentoptions.Asaframeworkfordevelopingandevaluatingcomplexhypothesesaboutsystems,theSEMusestwoormorestructuralequationstomodelmultivariatecausalrelationships.Causalmodelsinvolvingeithermanifestvariables,latentvariables,orbotharetypicallydevelopedbasedontheoreticalknowledgeanddesignedtorepresentcompetinghypothesesabouttheprocessesresponsiblefordatastructure.Anothermajorchallengeformodelingthecomplexityofoursystemsistheuncertaintyduetodataquality,measuringerrors,orotherunpredictableunderlyingmechanisms.TheBayesiananalysishasbeenwidelyusedforthis.TheBayesiananalysisregardsparametersasrandomvariablesdrawnfrompriordistributionsthatrepresentourpreviousknowledgeaboutthatvariable.Parametersarethenestimatedasacombinationoflikelihood,theirpriordistributions,andtheirposteriordistribution(i.e.,uncertaintyanalysis).Allstatisticalinferences(pointandintervalestimates,hypothesistests)thenfollowfromposteriorsummaries.Whenexactanalyticalsolutionsarenotpossible,commonincomplexanalyses,theBayesiananalysisestimatesparametervalues(andlatent

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variables)fromtheposteriordistributionusingtheMonteCarloMarkovChain(MCMC)approach,generatingcloseapproximationstotherealparameters.Thisanalyticalframeworkprovidesgreatflexibilityintheestimationoftheparametersandallowstheanalysisoffairlycomplexproblems,asinourcase.VulnerabilityAnalysiswillbeperformedunderalternativescenarios.WewillconveneinourfirstyeartodevelopdifferentoptionsforEES.Modeltrialswillbeusedtotrainusinrevisingthescenarios.MAJORRESULTSWecomparedlifecycleenvironmentalimpactsfromalternativePV-CdTe(cadmiumtelluride),CIGS(copperindiumgalliumdiselenide),Zn3P2(zincphosphide),andCZTS(copperzinctinsulfide).Acradletogatelifecycleassessmentwasconductedtounderstandtheenvironmentalimpactsfromthesetechnologies.TheimpactsfromZn3P2andCdTeweresimilarandlowerthantheimpactsfromCZTSandCIGS.WhileCdTehasthetoxicCdelement,theecotoxicityimpactfrommaterialacquisitionandprocessingwashigherforZnandPthanforCdTe.InCIGS,theecotoxicityimpactcamemainlyfromGaandwouldbesignificantlyreducedifCZTSweretoreplaceCIGSinthecommercialmarket.Forallfourthinfilmsstudied,thecontributionofrawmaterialstototalimpactwasmuchlowerthantheimpactcomingfromelectricityconsumptionduringthemanufacturingstage.Therefore,toreduceenvironmentalimpact,futurePVtechnologydevelopmentshouldfocusmoreontheprocessimprovement.ThemanufacturingstagesthatcontributedmosttotheimpactweretheabsorberlayerforCIGSandCZTSandthesubstratecleaningforCdTeandZn3P2.WehaveextendedtheassessmentofsinglePVcells/modulestoinvestigateitsbroadersocialimpactswhileconsideringthetechnologyfromthewholebuildingperspective.WestudiedhowthePVtechnology–asanovelgreenbuildingtechnology–mightinterferewiththebuildinguser’spro-environmentalattitudesandbehaviors.TheInstitutefortheBuiltEnvironmentatColoradoStateUniversityliststhefirstandforemostimportantaspectofagreenbuildingas“buildingsthatteach”.Toempiricallyinvestigatewhetherandhowagreenbuildingaffordseffectivecommunicationofsustainabilitytoitsusers,weusedacampusLeadershipinEnergyandEnvironmentalDesign(LEED)-certifiedbuildingtosurveythebuildingusersontheirperceptionsaboutgreendesignsimplementedinthebuildingatdifferentspatialscales(Wuetal.2017b).Theresultssuggestedthatusers’perceptionsaboutgreendesignsareexperiencedatdifferentspatialscales.Whenoneprefersadesignattheproduct-scale,suchastheeducationalsigns,(s)hetendstoneglectthelargerspace-scaledesign,suchasthetallwindowsandaccesstooutsideviews.Thisfindingofdichotomousspatialperspectivesofapersonmightbefurthermanipulatedwhendesigningagreenbuildingandimplementinggreendesignsatmultiplespatialscales.Forexample,otherthanconsideringthetechnologicaldetails,oneneedstoconsiderwhereandhowtolocateanon-siterenewableenergytechnologysuchasPVtomosteffectivelycommunicatesustainability.TopromotethedevelopmentofSocialLifeCycleAssessment(SLCA),weconductedacomprehensivereviewofrecentlydevelopedframeworks,methods,andcharacterizationmodelsforimpactassessmentforfuturemethoddevelopersandSLCApractitioners(Wuetal.,2014).

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Wealsoarguethatsociallifecycleimpactassessments(SLCIA)needtoincorporateeitheratypeIortypeIIcharacterizationmodel.Weimprovedbothmodelsbyintroducingexplicitcausalitybyusingstatisticmodelingthroughdevelopmentof(1)aquantitativeapproachtosimultaneouslyidentifyimpactpathwaysoftypeIImodelswithmultipleimpactcategories,targetingSLCIAmethoddevelopers,and(2)anewhybridmodeltoestablishcausalitybetweeninventoryindicatorsandsubcategories,targetingsociallifecycleassessmentpractitioners.MethodsCausalityestablishmentsfortypeIIimpactpathwaysandthenewhybridmodelarethecorerequirementsforthisstudy.Weusedstructuralequationmodeling(SEM)toidentifytheimpactpathwaysfortypeIIcharacterizationmodels,thereforeresolvingtheissuesofunobservabilityandunvalidatibilityintypeIImodels.Usingcountry-leveldatafromtheWorldBank,themethodwasappliedtoanexample(Fig.1).ThisstudywasthefirstattemptinusingstatisticcausalmodelstoquantitativelyidentifyunobservableimpactpathwaysofthetypeIImodelandtodevelopahybridmodelforSLCIA.ASEMthatincorporatestemporalprecedenceenablesidentificationofimpactpathwayswithmultipleunobservableimpactcategories.ThehybridmodelusingBayesiannetworksrepresentsthesubcategoriesinposteriorprobabilitiesinsteadofabsolutescores,helpingcompaniestobetterdevelopinstructionsforfuturemanagementpractices(Wu,etal.,2015).Furthermore,wearguedthatwhiletechnology-orientedsustainabilityassessmentframeworks(i.e.focusingandmeasuringimpactsfromalternativetechnologies)arenecessary.Whilehuman–environmentinteractionhasbeenstudiedextensively,itisrarelyaddressedinthesustainabilityassessmentframework.Wehavestudiedhuman-builtenvironmentinteractioninthecontextofgreenbuildingsboththeoretically(Wuetal.2017a)andempirically(Wuetal.2017b).Thisinteraction,combinedwiththeprogressaddressingthecontinuousimprovementeffortsmadebyanentity,thetemporal,spatial,andbehavioraldynamicscanbesimultaneouslyaddressedinalifecyclesustainabilityassessmentusingagreenbuildingdevelopmentexample(Wuetal.2017c).

Fig.1.TwotypesofSLCIA,theirlimitations,theproposedapproachesfortheidentificationofimpactpathwaysfortypeIIcharacterizationmodelandthedevelopmentofahybridtypeI/IIcharacterizationmodel.

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Wealsoattemptedtodevelopasocialhandprint/footprint(SH/F)reportingframeworkfortheminingindustrythatcanbeintegratedintoproductsociallifecycleassessment(S-LCA).WetestedtheassessmentframeworkbycomparingthesocialperformanceofaverageresourceextractionfortwomajorPVtechnologiesintheU.S.–thepoly-SiandtheCdTePV.WeselectedPVbecausearecentnationwideGalluppollshowedthatmajorityofAmericansseesolarenergyasthetopchoiceamongdomesticenergysources,withfourfifthsofrespondentssayingtheU.S.shouldplacemoreemphasisonsolardevelopmentthananyotherenergysource.TwoexistingSLCAframeworksareusedasthestartingpoint–theUNEPSLCAguidelinesandthePREhandbook.TwoimportantprinciplesadoptedfromGRIandthePREhandbookareusedforconstructingtheframework:1)Measurebothpositiveandnegativeimpacts;and2)Maintaininclusivenessandcompletenesswhilefocusingonmaterialisticissues,sothatonlystakeholdersaffectedbytheminingindustryareincludedintheassessmentandthosesocialthemes/topicsthataresignificantfortheevaluationareincluded.Weusedthequantitativeapproachindevelopingourframeworkandtheimpactassessmentmethod.Thescale-basedapproachwillalsobebrieflydiscussedanddemonstratedhypothetically.WeusedtheSH/FframeworktocomparethesocialimpactsforthematerialextractionstageoftwoPVtechnologies–thepoly-SiandtheCdTePV.Thecomparisonwouldbebasedona1m2finalPVmodulewithoutfurthernormalizationtoenergyproductionefficiency.Thepoly-Sitechnologyismostwidelydeployed–with90%marketshareinOECDNorthAmericain2010,followedbyCdTewith9%marketshare.Theframeworkcanfurtherincorporateatemporalscaletoobservethechangingperformanceforindividualmines,andtoacknowledgewhethercontinuouseffortsaremadecollectivelytowardsustainabilityatthesocietalscale.Practically,itcanalsoinformpurchasingdecisionsfordownstreamcompaniesfromtheperspectiveofsuppliers’businessresilienceregardingsocialsustainability(Fig.2).

Fig. 2. The structure of our SH/F framework contains following hierarchies: 1) the stakeholder groups, 2) the social themes under each stakeholder group, 3) the social topics under each social theme, and 4) the performance indicator for each social topic (Wu et al., in preparation).

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Finally,currentsustainabilityassessmentframeworksaretechnology-oriented–bothfocusingandmeasuringimpactsfromalternativetechnologies.Nevertheless,technologyalone,withoutconsiderationofhuman-object/-environmentinteractionandbehavioralconsequences,cannotachievesustainability.Ahumandimensionmustbeaddedandaddressedthroughculturalsustainability.Thisisespeciallyapplicableforthebuiltenvironment,whichreflectsthepastandshapesthefutureculture.Whilehuman–environmentinteractionhasbeenstudiedextensively,itisrarelyaddressedinthesustainabilityassessmentframeworks.Wehavestudiedhuman-builtenvironmentinteractioninthecontextofgreenbuildingsboththeoreticallyandempirically.Bycombiningsuchinteractionswiththeprogressaddressingthecontinuousimprovementeffortsmadebyanentity,thetemporal,spatial,andbehavioraldynamicscanbesimultaneouslyaddressedinalifecyclesustainabilityassessmentusingagreenbuildingdevelopmentexample(Fig.3).OUTCOMES

Thesis1. Wu,SusieR.2016.Greenbuildingsandgreenusers:anassessmentofusinggreen

buildingenvironmentstocommunicatesustainabilitytousers.Ph.D.,MichiganStateUniversity.

2. Fan,A.Simulationofsmartelectricitygridsandmarketswithagent-basedmodeling,inprogress.MichiganStateUniversity.

Journalpublications&bookchapters1. Collier,J.,S.Wu,andD.Apul.2014.LifecycleenvironmentalimpactsfromCZTSand

Zn3P2thinfilmphotovoltaiccells.Energy74:314-321.2. Wu,R.,D.Yang,andJ.Chen.2014.Sociallifecycleassessmentrevisited.

Sustainability6(7):4200-4226.3. Wu,S.R.,Chen,J.,Apul,D.,Fan,P.,Yan,Y.,Fan,Y.andZhou,P.,2015.Causalityinsocial

lifecycleimpactassessment(SLCIA).TheInternationalJournalofLifeCycleAssessment,20(9),pp.1312-1323.

4. Fan,Y.,Wu,R.,Chen,J.andApul,D.,2015.AReviewofSocialLifeCycleAssessmentMethodologies.InSocialLifeCycleAssessment(pp.1-23).SpringerSingapore.

Fig. 3. The role of culture and technology in sustainability development.

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5. Wu,S.R.,M.Greaves,J.Chen.,andS.Grady.2017.Greenbuildingsneedgreenoccupants:AresearchframeworkthroughthelensoftheTheoryofPlannedBehavior.ArchitecturalScienceReview60(1):5-14.

6. Wu,R.,P.Fan,andJ.Chen.2016.Incorporatingcultureintosustainabledevelopment:Aculturalsustainabilityindexframeworkforgreenbuildings.SustainableDevelopment24(1):64-76.

7. Fan,Y,J.Chen,G.Shirkey,R.John,R.Wu,H.Park,C.Shao.2016.Applicationsofstructuralequationmodeling(SEM)inecologicalresearch:Anupdatedreview.EcologicalProcesses5:19DOI:10.1186/s13717-016-0063-3

8. Wu,S.R.,X.Li,D.Apul,V.Breeze,Y.Tang,Y.Fan,andJ.Chen*.2017.Agent-basedmodelingoftemporalandspatialdynamicsinlifecyclesustainabilityassessment.JournalofIndustrialEcologyDOI:10.1111/jiec.12666

9. Wu,S.R,S.K.Kim,H.Park,P.Fan,A.Ligmann-Zielinska,andJ.Chen*.2017.Howgreenbuildingscommunicategreendesigntothebuildingusers?AsurveystudyonaLEED-certifiedbuilding.JournalofGreenBuilding12(3):85-100.

10. Fan,Y.,Beyza,G.,Chen,J.,Wu,S.R.,Zhou,P.,2016.Pro-environmentalbehaviorsandknowledge:AcasestudyofparkvisitorsinToledo,Ohio.EnvironmentalProtectionandEcology(revisionsubmitted)

11. Wu,S.R.,I.Celik,andD.Apul.Asocialhandprint/footprintcalculationframeworkforresourceextractionindustry:acasestudyoncomparingtwomajorPVtechnologiesintheU.S.JournalofCleanProductions(inpreparation).

12. Wu,S.R.,J.Chen,andothers.Human-environmentinteractionandthebehavioralconsequencesinsustainability.Nature-Sustainability(inpreparation)

Models&CodesTheoriginalsourcecodesforLCA(WuSR(2015)Softwaremodelsforcausalityinsociallifecycleimpact)isopenlypostedat:http://lees.geo.msu.edu/resources/lca.html

LCATrainingWorkshopToexpandourlessononLCAapplicationsinbroadly-definedenvironmentalscience,a2-daytrainingworkshopwasorganizedattheLEESLabduringMay12-13,2017.NineresearchassistantattheMSUreceivedthetrainingbyDr.forthelabbyBillKungofEcovaneEnvironmental.Nineresearchassistantsreceivedthetraining,withasoftwareprovidedbyDr.Kungfor30days:SusieWu(Postdoc),GabrielaShirkey(M.S.student),FeiLei(Postdoc),CheyenneLei(Doctoralstudent),MaoweiLiang(doctoralstudent),VincenzoGiannico(visitingdoctoralstudent,Italy),PeiroSciusco(visitingMSstudent,Italy),RanjeetJohn(postdoc),HogeunPark(doctoralstudent).Duringtheworkshop,wediscussedLCA,eco-designandgreensupplychainissues,aswellaspolicy

Open access of LCA Modeling codes through the LEES Lab at the Michigan State University

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andstandarddevelopmentaroundLCAandapplications.Wealsoexploredchancesforcollaborationforthefuture.

Presentations1. Fan,Y.DemandforsolarelectricityfromtheBRICScountriesinthefuture.American

GeographyUnionFallMeeting,SanFrancisco,2015.2. Wu,S.R.,M.Green,J.Chen,A.Yang,andY.Tang.Greenbuildingdesignandvisual

persuasiononoccupants’pro-environmentalbehaviors.Inproceedingsofthe49thInternationalconferenceoftheArchitecturalScienceAssociation,,Melbourne,pp.133-142,December2-4,2015.

3. Chen,J.Harmonizingpeopleandnature.InvitedSeminarSeries,HuadongNormalUniversity,August2,2015

4. Chen,J.Harmonizingnatureandpeople.HanoverSeminarSeries(invited),Dept.ofForestry,MSU.March17,2015.

5. Chen,J.RenewedChallenges:PeoplevsEnvironment.WenzhouUniversity,November4,2016