先进可再生能源技术创新议程

■TIrINFORMATIONTECHNOLOGY

II&INNOVATIONFOUNDATION

AnInnovationAgendaforAdvanced

RenewableEnergyTechnologies

ROBERTROZANSKY|DECEMBER2020

Innovationinrenewableenergytechnologies,tappingsolar,wind,geothermalandwater

resources,couldunlockmassivedecarbonizationopportunities.Butitwillnothappenwithout

increased,sustained,andwell-targetedfederalinvestments.

KEYTAKEAWAYS

■Recentrapidprogressinwindandsolarpowermarksonlythebeginningofthe

renewablesrevolution.Ifcleanenergyistosupplantunabatedfossilfuels,especiallyin

thedevelopingworld,renewablesmustbecomeevenmoreaffordableandreliable.

■Therearemanyexcitingopportunitiestoaccelerateinnovationinsolarphotovoltaics,

wind,geothermal,concentratingsolar,hydro,andmarinepowertechnologies.

■Advancedrenewablesthatcanprovidefirmpowertoalleviatethevariabilityplaguing

today*ssolarPVandwindsystemsareparticularlyimportanttopursueinlightofthe

challengesthatfacealternativeslikenuclearpowerandcafboncapture.

■Federalresearch,developmentanddemonstrationprogramsineachofthesixadvanced

renewablestechnologyareasshouldfocusonadistinctsetofchallengestobring

innovationstomaturityandjumpstartdeployment.

■Federalinvestmentmustincreasesignificantlyifthesechallengesaretobesurmounted

rapidlyenoughforadvancedrenewablestocontributeatscaletothetransitiontolow-

carbonenergyinthecomingdecades.

INTRODUCTION

Thecleanenergysuccessstoryofthe21stcenturyistheastonishingrateatwhichsolar

photovoltaic(PV)andwindpowerhavegottencheaperandexpandedaroundtheglobe,becoming

mainstreamsourcesofcarbon-freeelectricity.IntheUnitedStates,solarPVandwindhavegrown

fromanegligibleshareofelectric计ygenerationtwodecadesagoto2percentand7percent,

respectively,ofelectricitygenerationtoday.1

Yet,thisprogressmarksthebeginningratherthantheendoftherenewablesrevolution.The

InternationalEnergyAgency*s(IEA)SustainableDevelopmentScenario(SDS),inwhichglobal

warmingislimitedto2degreesCelsius,envisionsrenewables-agroupingthatstretcheswell

beyondsolarPVandwind-asthebedrockofthelow-carboneconomy,providingcleanpower,

heattransportation,andothervitalservices.By2030inlEA'sscenario,ameredecadeaway,

theshareoftheworld'selectricitydrawnfromrenewableresourceswillhavedoubled.By2040,

itwillbe72percent.2

Thereisnodoubtthatachievingsuchambitiousobjectiveswillrequireaggressiveandimmediate

deploymentofmaturerenewableenergytechnologies.Butastrategylimitedtodeploymentwould

beshortsighted.3Despiteimpressiveimprovements,renewablesfaceconstraintsaround

affordability,availability,andreliability.Ifcleanenergyistofullysupplantunabatedfossilfuels,

especiallyinthedevelopingworld,theseconstraintsmustbeovercome.

Innovationinadvancedrenewableenergytechnologiescancatalyzeamassivecleanenergybuildout

andhelpdrawdownglobalemissions.

Thepossibilitiesareexciting.Thinzflexiblesolarpanelscouldbemanufacturedatlowcostand

integratedintothearchitectureofdense,urbanenvironments.Floatingplatformscouldsupport

massivewindturbinesindeepwatersfaroffthecoasts.Geothermalreservoirsthatarebuilt

ratherthandiscovered,coulddrawalways-onpowerfromthehotrockdeepbeneaththeEarth's

surface.Thesearejustafewexamples.Innovationcanturnmanyofthesepossibilitiesinto

realitieSzunlockingmassivedecarbonizationopportunitiesandcomplementingdeploymentof

today'sstate-of-the-arttechnologies.

Thatstateoftheartowesagreatdebttofederalinvestmentsininnovationgoingbackdecades.

Alladvancednations,includingtheUnitedStatesthroughitsCongressandDepartmentof

Energy(DOE),shouldnowbuildonthatlegacyanddriveforwardanambitiousrenewables

innovationagenda.DOEhasalreadylaidthegroundworkinstudiessuchasWindVision,

HydropowerVision,andGeoVision.4Thisbodyofworkprovidesamplereasontobelievethat

innovationinadvancedrenewableenergytechnologiescancatalyzeamassivecleanenergy

buildoutandhelpdrawdownglobalemissions.

Thisreportputsforwardaninnovationagendaforsolar,wind,geothermalandwaterpower.It

organizesthekeytechnologiesintotwocategories:thosethatsupplyvariableenergyfwhichis

onlyproducedasaresourceisavailable,andthosethatsupplyfirmenergy,whichisavailableas

needed.Thetechnologiesineachcategoryhavecommonroles,challenges,andopportunities.

Theyalsocomplementoneanother:Firmrenewablesenableverycheapvariablerenewablesto

providemoreenergythantheyotherwisewould.Withinthetwocategories,eachsubsection

summarizesthecurrentstatusofatechnology,describesitspotentialtocontributeto

decarbonization,andidentifiesopportunitiesforthefederalgovernmenttoaccelerateinnovation.

Thereportoffersseveraloverarchingrecommendations:

CongressshouldsignificantlyincreaseDOE'sfundingforrenewableenergyresearch,

development,anddemonstration(RD&D)ZconsistentwithInformationTechnologyand

InformationFoundation(ITIF)proposalsfortheentirefederalportfolio.5

2.CongressandDOEshouldensurewindandsolarPVZthetwomajorvariablerenewable

technologieszcanfulfilltheirpromisetoprovidethebulkofnewlow-carbonenergy

capacitybydrivingRD&Dtoimprovetheefficiencyofgeneratingdevicesandpromoting

theirintegrationintotheelectricgrid.

3.CongressandDOEshouldsupporttheimprovementoffirmrenewablepower

technologies-suchasgeothermalenergy,concentratingsolarpower(CSP),hydropower

andmarinepower-thatwouldofferreliabilityandotherbenefitsforagriddominatedby

variablerenewables,byensuringtheycanbedeployedindiverselocationsatlowcost.

Advancedrenewableenergytechnologiesarenotmagicbulletsforclimateandcleanenergy.

Gettingtozeroemissionswillrequireadvancesingridtechnologies,solutionsforhard-to-

decarbonizesectorssuchasshippingandchemicalmanufacturing,andlikelynegativeemissions

technologiesaswell.6Otherelectricitygenerationtechnologies,suchasnuclearpowerandfossil

fuelswithcarboncaptureandstorage(CCS),mightalsoplayvaluablerolesandshouldcontinue

tobepursued.

Advancedrenewablesare,however,indispensable.Theywillbetheconduitslinkingtheplanet's

inexhaustiblenaturalresourcestocleanenergyathrivingglobalsocietycandependon.

RENEWABLES:THEFOUNDATIONOFACLEANELECTRICGRID

Toavoidtheworsteffectsofclimatechange,theworld'snationsmusttransformaglobal

economybuiltonfossilfuelsintoonethatemitslittletonocarbon,whilesupportingthe

livelihoodsandaspirationsofagrowingpopulationofalmosteightbillion.Theelectricitysector

isanaturalfocusforthistransformation.Alargechunkofemissionswillbeeliminatedif

electricitygenerationisdecarbonizedandadditionalendusessuchastransportation

areelectrified.

Electricityandheatareresponsibletodayforaboutaquarterofallglobalgreenhousegas

emissions.7Asmoreconsumersenterthemiddleclassandalready-wealthyconsumersintens讦y

theiruseofelectricity-consumingdevicessuchascomputersandmobilephones,globaldemand

forelectricityisexpectedtocontinuetogrow.8

Indeed,growthcouldaccelerateifelectricvehiclesandheatpumpsprovidearapidlyrisingshare

oftransportationandheatingenergyservices.Electricitymayalsobeusedtoproducecarbon-

neutralfuelssuchashydrogenforuseinapplicationsasdiverseaslong-haultrucking,process

heatforchemicalproduction,andlong-durationenergystorage.

Renewableenergytechnologiesarethebestcandidatestoprovidethemajorityoffuturelow-

carbonelectricity,especiallygiventhepoliticalandeconomicbarriersfacingotherlow-carbon

powersourcessuchasnuclearpowerandfossilfuelswithCCS.IEAdefinesrenewableenergy

sourcesasthose"derivedfromnaturalprocesses**and**replenishedatafasterratethantheyare

consumed."9IEAincludessolar,wind,marine,geothermal,andhydropower;bioenergy;and

hydrogenandotherfuelsderivedfromrenewablesourcesinthiscategory.lEA'sSDSprojects

thattheseresourceswillsupply67percentofglobalelectricitygenerationby2040,while

unabatedfossilfuelswillfallto21percent10

Thislow-carbonfuturewillbecomemorelikelyifinnovationleadstoimprovementsinthe

followingareas:

Costandperformance：Renewabletechnologiesmustprovideenergythatiscost-

competitivewithfossilfuelstoacceleratethepaceoftheiradoptionzbuildpoliticalwill

fordecarbonization,andincentivizedeploymentinportsoftheworldwhereliftingpeople

outofpovertythroughenergyaccessremainsanurgentpriority.

Resourceaccess：Technologicalimprovementsmustallowrenewableenergytobe

harnessedinabroaderrangeofgeographiclocations,whereresourcesareinaccessibleor

ofinsufficientqualitytobedevelopednow.

Gridintegrationandservices：Renewabletechnologiesmustbecomemorereliableand

flexibleandprovideotheressentialgridservicestofurtherdecreasethecostof

decarbonizationandallowgridoperatorstomakeasmoothtransitionawayfromfossil

resources.

Environmentalimpact：Innovationmustreducethelocalandregionalenvironmental

impactsofrenewableinfrastructureandprojects,whichcouldbeunsustainableifthey

arebuiltoutatamassivescale.

Globalcompetitiveness：Bydrivinginnovationinrenewables,theUnitedStatescan

establishexpertise,supplychains,andmanufacturingcapabilitiesthatsupportdomestic

economicgrowthanddemonstrateleadershiponclimatechange.

ANINNOVATIONAGENDAFORVARIABLERENEWABLEENERGYRESOURCES

SolarPVandwindarevariableelectricitygenerationresources;theyproducepoweronlywhen

thewindisblowing,orthesunisshining.Theresourcestheyarereplacingaretypicallyfirmand

abletoproduceelectricityondemandregardlessoftheweatherortimeofday.Thevariable

natureofwindandsolarPVcomplicatestheirintegrationintotheelectricgrid.Gridoperators

mustbalancesupplyanddemandatalltimes.WhenvariationsinwindorsolarPVoutputoccur,

whetherforafewsecondsorformanydayszoperatorsmustadjustbybringingonadditional

supplyorlimitingdemand.

Despitethisdrawback,solarPVandwindhaveemergedasthemostpromisingcandidatesto

supplylow-carbonelectricitytotheworld'sgrids.SolarPVisthefastest-growingformofnew

energyproduction,andisexpectedtodominatenewelectricitygenerationinthenearfuture.IEA

recentlyproclaimedsolarPV"thenewkingofelectricity/1dethroningcoal.11DOEestimates970

gigawatts(GW)ofdomesticsolarPVcapacitycouldbeinplaceby2050,roughlyequalingthe

currentinstalledcapacityforallpowergeneration.12Windpoweriscurrentlythesecond-most

widelydeployedsourceofrenewablepowerglobally,afterhydropowerandDOEhasestimated

that400GWofdomesticonshoreandoffshorewindareachievableby2050.13

Akeyreasonforthisgrowth,andoptimismaboutthefuture,isbothtechnologieshavebecome

14

inexpensiveinmuchoftheworld,evencomparedwithfossilfuels.Since2009zthelevelized

costsofunsubsidized,utility-scalesolarPVandwindpowerhavedeclinedby90percentand70

percent,respectively.15ArecentreportfromtheInternationalRenewableEnergyAgency(IRENA)

foundthatoverhalfoftherenewablegenerationcapacityaddedin2019willproducepowermore

affordablythanthecheapestnewcoalplants.16

SeveralfactorshavecombinedtodrivedownsolarPVandwindcostsandimprovetheir

performance,includingtechnologicalimprovements,favorablepolicies,rapidlearningbydoing,

andcompetition.17Manyofthesefactorsareexpectedtocontinuetobepresentinthefuture.

Solarandwindresourcesareabundant.Themanufacturingandsupplychaininfrastructure

neededtocontinuetoscaleupdeploymentareinplace.Thesetechnologieshavegained

widespreadpublicacceptanceandentrenchedpolicysupportthroughouttheinternational

community.

YetthedemandsthatwillbeplacedonsolarPVandwindtechnologiesarehigh:Theymust

supplypredictablepowerfromunpredictableresources,whileoutperformingthefossil

technologiesaroundwhichsocietyhasbeenbuilt.Andthereisplentyofroomto

accelerateprogress.

WhyInnovationIsStillNeededinSolarPVandWindPower

VariabilityisthebiggestchallengefacingsolarPVandwindpower,andinnovationcanhelp

addressit.ThehoursofthedaywhensolarPVandwindproducethemostpowerdonotneatly

correspondtothosewhenconsumerswantpower.AcommonloadprofileinCalifornia,knownas

the“duck”curveforitsappearanceonagraphofdailypowerconsumption,isagreatexample.

SolarPVgenerationpeaksatmidday,butifthereisn'tenoughdemandatthattime,grid

operatorsmaybeforcedtocurtailgeneration,effectivelywastingpower.Ontheotherhand,

demandtypicallyrampsuprapidlyintheevening,justasthesunissetting,forcingoperatorsto

findfirmelectricitysourcestomeetit.18Althoughmanysolutionstothechallengeofvariability

liebeyondthegeneratingequipmentitself(suchasincreasedenergystorageandtransmission

capacity,smartgridtechnologies,newpricingmechanisms,andimprovedplanningandtoolsfor

gridoperation),innovationthatenhancesthesetechnologies'abilitytoprovidereliablepowerand

essentialreliabil计yservicesisaworthwhileobjective.

AnotherreasoninnovationinsolarPVandwindremainsimportantisthereareloomingbarriersto

sustainingprogressthrougheconomiesofscaleandlearningbydoing.Physicallimitationssuch

asthetheoreticalmaximumefficienciesofcrystalline-silicon(c-Si)solarcellsandhorizontal-axis

windturbineswillconstraintheircurrenttrajectories.Further,solarPVandwindpowerbecome

lessvaluableastheirpenetrationlevelsonthegridrise,notonlybecauseofphenomenasuchas

theduckcurvebutalsoduetoincreasingcostsofland.19ResearchbySaptarshiDasetal.finds

thatdiminishingmarginalrevenuefromincreasedpenetrationofsolarPVandwindpowermay

outpacedecliningcostsduetotechnologicalprogress.Ifthatprovestrue,thesetechnologieswill

losetheireconomicadvantagesinmanyplaces.20

AstrategicfederalinnovationportfolioforsolarPVandwindpowershouldinvestheavilyto

improveexistingtechnologies,investigatealternativepathways,andlaythegroundworkfor

variablerenewabletechnologiestobedevelopedinwaysthatareenvironmentallysustainable

andsupportiveoftheU.S.economy.InnovationinsolarPVwillhelpimproveperformance,

increasetheutilityofsolarresourcesforthegrid,andcontinuedrivingcostsdownevenathigh

penetrationlevels.Alternativestoc-Simaterialsareworthyofexplorationinpursuitofthesegoals.

Innovationinwindenergywillallowdevelopersandoperatorstocontinuetoachievecostdeclines

bybuildinglarger,moreefficientturbines,andtoexpandthegrowingmarketinoffshorewind.

Floatingoffshorewind,whichallowswind-projectdevelopmentindeepwaters,suchasonefinds

offtheU.S.westcoastisapproachingcommercialmotur计yandrequiresdemonstration.

ThefollowingtwosectionsexplorethepotentialandinnovationneedsofsolarPVandwindpower

ingreaterdetail.

SolarPhotovoltaics

Solarphotovoltaicpowerusesspecialmaterialstoconvertincidentphotonsfromthesunintoan

electricalcurrent.Ithasmanyattractivefeatures.Itcanbeinstalledalmostanywhere.Itis

modularandcanbebuiltathugelyvariedscalesfromutility-scaleinstallationsthatprovide

hundredsofmegawatts(MW)ofpower(seefigure1)tocommercialandresidentialsystemsthat

supportindividualbuildings.SolarPVisrelativelysimpletoinstallandmaintain,withnomoving

parts.Mostimportantly,PVinoperationemitsnocarbon,anditslifecycleemissionsarelow.

SeveralcountriesaidedthejourneyofsolarPVfromthelabtothemainstreamenergy.The

UnitedStateswasanearlygloballeader,investingheavilyinresearchanddevelopment(R&D)in

the1970sand1980s.Inthe1990sand2000s,JapanandGermanyadvancedthetechnology

bycreatingin计iolmarketswithinnovativepoliciesthatdrovedemand.Overthepastdecadeand

ahalf,Chinahasdramaticallyscaledupproduction,reducingmanufacturingcostsinturn.21

SolarPVdeploymentincreased36-foldfrom2009to2019,anditnowsuppliesalmost3

percentofglobalelectricity.Themost-conservativeIEAscenario(uStatedPolicies”)projectsthat

itwillmeetalmostathirdofglobalelectricitydemandgrowththrough2030.22A2019review

articleinScienceestimatesthat10terawatts(TW)ofsolarcapacitycouldbeinstalledby2030,

and30-70TWcouldbeinstalledby2050,upfromabout630GWasoftheendof2019.23

Figure1:The550MWTopazSolarFarminCaliforniaisamongthelargestsolarPVsystemsintheUnitedStates.

ImagecourtesyoftheU.S.FishandWildlifeService.24

SolarPVinlEA'sSustainableDevelopmentScenario(SDS)

SolarPVisamongthefewtechnologiesIEAlabels"ontrack"withitsSDS.TheSDScallsfor

solarPVgenerationtoincreaseby15percentannuallybetween2019and2030.In2019,solar

PVgenerationincreasedby22percentto131Terawatt-hours(TWh).25

Figure2:SolarPVinlEA'sSustainableDevelopmentScenario.26

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■Historical■RequiredforSDS

TheCaseforInnovationinSolarPV

ThefutureofsolarPVisbright.Technologicalprogressandeconomiesofscalehavecaused

pricestoplummet.Itiscompetitivewith,ifnotcheaperthan,fossil-fuel-poweredgenerationin

manypartsoftheworld.Thereiseveryreasontobelievethatitscostandefficiencywillcontinue

toimproveastheindustrycontinuestogrow.Thequestioniswhetherthepacecanbe

accelerated.

VarunSivaramandhiscolleagueshavearguedthatpowermayneedtoreachapricepointof25

centsperWattifitistofulfillthemassivegrowthcalledforbydeepdecarbonizationscenarios.27

Asofearly2020,thepriceofU.S.solarsystemsrangedfrom$1.50to$4perw。什.28Crystalline

silicon,thematerialusedinmorethan90percentofsolarmodulestoday,maynotbeableto

reachsuchlowcosts.29Softcostsofinstallationandbalance-of-system(BOS)equipmentwhich

areevenmorecostlythanmodulesinmostsystems,mustbecurbedaswell.

AsthesolarPVmanufacturingindustryspendsveryI计tieonR&D,itisunlikelytoaddressmany

oftheseinnovationchallengesonitsown.30Chino'sproductionsurgeinthe2000s,which

ensuredc-Si'sdominance,eliminatedmanyinnovativecompaniesandshiftedthetechnological

trajectoryawayfromalternativematerialsthatmightultimatelybelesscostly.31

Governmentsshouldmoveswiftlytoaddresstheprivatesector'sshortcomingsinsolarPV

innovation.Keyprioritiesincludeloweringmodulecostsbyexploringalternativestoc-Siwith

superiorattributes(suchastheoreticalmaximumefficiencies),improvingtheintegrationofsolar

powerintothegrid,andreducingnon-moduleBOSandsoftcosts.

DOEPortfolioinBrief

DOE'ssolarPVprogramishousedintheSolarEnergyTechnologiesOffice(SETO).Itfocuseson

improvingPVmoduleefficiencyandstabilitythroughR&Donadvancedsiliconprocessesand

othercellmaterialsandarchitectures;enhancingPVsystemsintegrationintothegrid;reducing

BOSandsoftcosts;andenhancingmanufacturingandcompetitiveness.32Recentinitiatives

includea$20millionperovskiteR&Dprogramthattargetsdeviceefficiencyandstability,

manufacturing,andvalidationandbankability,anda$3millionAmerican-MadeSolarPrize,

whichaimstohelpboostU.S.-basedsolarmanufacturing.33

InnovationChallenges

InnovationChallenge#1:Developnewmaterialswiththepotentialtobemoreefficientandlowercost

thanc-Si.

AfederalRD&DstrategyshouldseektoadvancepromisingPVmaterialswithpropertiesthatmay

leadtocheaper,moreefficientsolarcells,andcouldemergeassuperioralternativestoc-Siin

utility-scaleapplicationsorinspecificmarketssuchasbuilding-integratedsolar.Therearea

numberofalternativestoc-Si.OrganicPVmaterialscomposedofcarbon-richpolymerscapture

lightwithhighefficiency.34Quantumdotsgenerateelectricityusingsemiconductorparticlesa

fewnanometerswideandareeasytomanufacture.35Ill-Vsemiconductorscanachieve

exceptionallyhighefficiencies(29.1percentforsingle-junctioncells)andhaveother

advantageousphysicalproperties.Combiningthesematerialsandothers,includingc-Si,in

multi-junctionarchitecturesmultipliestheopportun计ies.

Perovskitesareworthyofspecialattention.Theyareaclassofhybridorganic-inorganicmaterials

thathavedemonstratedhighconversionefficiencies(over25percentasof2020).Theymaybe

tunedtoabsorbdifferentfrequenciesoflight,aremadeofcheapandabundantmaterials,have

thepotentialtobemanufacturedatlowcost,andmaybedevelopedintothinfilms,appliedas

solarpaintorstackedwithothermaterialsintohigh-performancetandemarchitectures.The

majordrawbacksofperovskitesaretheirtendencytodegradeduetomoisture,light,andheat,

andtheenvironmentalimpactsofthelead-basedperovskiteabsorbersthatarecurrentlyused.

Importantly,perovskitesarecloserthanmostothernovelmaterialstocommercialization.36

■Recommendation：DOEshouldexpanditssupportforR&DofnewmaterialsforsolarPV

cellsandmodules,w计hastrongfocusonperovskites.Akeygoalshouldbeimprovingthe

reliabilityofperovskites,whichmaybeadvancedbyimprovingunderstandingoffailure

mechanisms.37Cellpacking,whichmakesupalargecomponentofthecostofflexiblePV

cells,mayalsobeimprovedthroughR&D,DOEinitiativestoadvanceperovskitesshould

collaboratecloselywiththenewlyestablishedU.S.ManufacturingofAdvancedPerovskites

(US-MAP)ConsortiumformedbyNationalRenewableEnergyLaboratory(NREL)and

severalacademiccenters.38

InnovationChallenge#2:ImprovetheefficiencyofPVmanufacturing.

SolarPVdeploymentcouldbeacceleratedifthecostofmanufacturingdeclinedfurther.However,

factory-leveldemonstrationofnewmanufacturingconceptswillcosttensofmillionsof

dollars,whichisbeyondthemeansofmanycompaniesthatseektopioneernewsolarproducts.

Newmanufacturingprocessesalsohavethepotentialtorevitalizedomesticmanufacturingof

solarPVcells.AstudybyMathewsandcolleagues,forexample,suggeststhatperovskitescould

bemanufacturedeconomicallyinamarketwithhighlaborrates,suchasthatoftheUnited

States.(ItshouldbenotedthatRD&Dinitiativesalonecannotspawnnewsolarmanufacturing

industries,andsuchinitiativesoughttobepairedwithdemand-pullpoliciesthattargetsolar

innovations.)

Recommendation：DOEshouldestablishanext-generationsolarenergymanufacturing

initiative,asproposedintheSolarEnergyResearchandDevelopmentActof2019(H.R.

3597).Suchaprogramwouldawardgrantsorcost-shareawardstosupportadvanced

solarenergymanufacturingtechnologiesandtechniquesinsolarcells,hardware,and

enablingtechnologies.39

InnovationChallenge#3:ReduceBOScostsofsolarPV,includinghardwareandnon-hardwarecosts.

Some40to60percentofthecostofsolarPVsystemscomesfromsomethingotherthanthe

electricity-generatingmodules.BOShardwareincludestheinverterandpowercontrolsystems,

whichconnectthesystemtothegridandensureitismanagedintelligently.40Suchhardware

alsoenablessolarPVtoprovidemorerobustvoltage,reactivepower,andotheressential

reliabilityservices.Non-hardware“soft”costsincludeinstallation,permitting,andfinancing.

Recommendation：CongressshouldincreasefundingforSETO'ssoftcoststeamand

programsthatsupportBOShardware,suchasitsworkinpowerelectronics.Giventhe

outsizedimpactoftheseexpensesontotalsolarenergycost,theyoughttobea

significantfocusoffederalinvestmentespeciallyconsideringcostreductionshereare

easiertoachievethantechnologicalbreakthroughsinsolarPVmaterialsorenhanced

manufacturingtechniques.Technicalsolutionstolowerhardwarecostsincludesolar

smartinvertersandcommunicationprotocolstomanagepowerfromsolarPVfleets.41

Solutionstoreduceso什costsincludeR&Donmarketandregulatoryanalysis,new

techno-economictools,andmethodologiesfordistributedresources.

InnovationChallenge#4:ImprovetheintegrationofsolarPVathighpenetrationinthegrid.

GridintegrationwillbecomeagreaterbarriertothedeploymentofsolarPVasitspenetrationin

thegridincreases.Theavailabilityofsolarpowervariesonsecond-by-second,dailyzandseasonal

timescales.Thesefluctuationsmustbedealtwith.Inaddition,becausesolaroutputfrom

generatingresourcesinthesameregionpeaksaroundthesametimeofday,itsvaluetendsto

declineaspenetrationrises,whichcouldleadtocurtailmentofproduction.Gridoperatorsmust

alsofindwaysforsolarPVresourcestoprovidegridservices—forinstance,usinggrid-forming

inverters.InvestmentfromDOEcouldhelpaddresssuchintegrationchallenges.

Recommendation：DOEshouldsupportthedemonstrationofmicrogridsandautonomous

energysystemswithhighlevelsofsolarpenetration.Suchprojectscouldenablelocalities

todevelopthetechnicalandregulatorytoolsneededtomanagehighpenetrationsofsolar

PV.Thedisseminationoflessonslearnedcouldhelpgridoperatorsprovidemorereliable

poweraswellasother