世界银行 -中低收入国家的屋顶太阳能潜力 Rooftop Solar Energy Potential in Low- and Middle-Income Countries

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GAPFUNDTECHNICALNOTES

ROOFTOPSOLARENERGYPOTENTIAL

INLOW-ANDMIDDLE-INCOMECOUNTRIES

March2026

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RooftopSolarEnergyPotential

inLow-andMiddle-IncomeCountries

1

Overview

Thisnoteservesasafoundationalresourcetoexplorethedynamicsandpotentialofaddressingurbanchallengesinlow-andmiddle-incomecountries(L&MICs)throughtheadoptionofrooftopsolarPV.Itoutlinesthecriticaldecision-makingfactorsnecessaryforunderstandingthecontextsinwhichrooftopsolarismosteffective,includingvarioususecases,businessmodels,fundingmechanisms,andpolicyconsiderations.Additionally,itprovidesacompilationoftoolsthatcanassistinassessingrooftoppotentialandguideimplementationstrategies.Thisnotedoesnotaimtobeastep-by-steptechnicalguidetosolarprojectimplementation

.2

Rather,itsprimaryobjectiveistoassistgovernments,utilities,policymakers,andurbanplannersincomprehensivelyconsideringthepotentialandincreasingdemandforrooftopsolarPV,therebyfacilitatinginformeddecision-makinginthetransitiontosustainableurbanenergysolutions.

Thenoteisstructuredintofivesections:

1.Introduction:Solarenergyasalow-costresource

2.Rooftopsolarenergy:Benefitsandlimitations

3.Specificusecasesforlowandmiddle-incomecountries

4.Policyincentivesandbusinessmodels

5.Toolstohelpevaluaterooftopsolarpotential

1.Introduction

Withthegrowingmigrationtourbanareas,thedemandforenergyisalsoincreasing.Globally,citiesaccountforaround75percentofglobalenergyconsumptionand70percentofglobalgreenhousegasemissions–figuresthataresettorise(InternationalEnergyAgency,2024).Buildingsareresponsiblefor60percentofemissionsonaverage,andupto80percentinsomecities(C40Cities,2024),andtheyaccountfornearly40percentofglobalenergy-relatedemissions(OECD,2022).

1AuthoredbyNikitaSanjayKulkarniundertheguidanceofChandanDeuskarfortheCityClimateFinanceGapFund.ChristophedeGouvelloandAugustinMariaprovidedvaluablefeedbackondraftsofthisnote.

2RefertoADB’s

HandbookForRooftopSolarDevelopment

InAsiaforadetailedguideforallstagesofsolarprojectdevelopmentfromprojectpreparation,systemdesign,procurement,implementationand

operation&Maintenance

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Hencedecarbonizingbuildingenergyuseisamongthehighestimpactactionsthatcitiescantakeindecarbonizingtheirenergysector.Thishighlightsthesignificantopportunitytoequipbuildingswithrenewableenergygenerationsystemssuchassolarphotovoltaics(PV).

SolarradiationisanaturallyabundantresourceavailableeverywhereonEarth,withitsintensityvaryingbylocationandtimeofyear.Utilizingsolarenergyforpowergenerationpresentsanopportunityforcitiestotransformordeveloptheirenergyinfrastructureandadvancetheirlow-carbonenergytransition.Rooftopsolarphotovoltaictechnologyoffersasustainablealternativetofossilfuels;deployingunderutilizedrooftopspacetogenerateelectricitycanreduceenergycostsandgeneratefinancialreturnstogovernments,individualhomeownersorlargeindustrialandcommercialbusinesseswhilehelpingtoreducegreenhousegasemissionsandimproveairqualityinacost-efficientway.

BOX1.1:Potentialelectricityproductionofasinglesolarpanel

Toestimatethepotentialelectricityproductionofasinglesolarpanel,let'sconsidera300-wattpanelthatreceivesanaverageof5hoursofdirectsunlighteachday.Wecancalculateitsdailyoutputwiththeformula:DailyOutput(kWh)=PanelWattage(W)×SunlightHoursperDay×PanelEfficiency.Forexample,300(W)×5(HoursperDay)×0.2=0.3kWh/day.Thismeansthepanelgenerates0.3kWhofelectricityeachday,totaling9kWhmonthly.Giventhis,tomeettheaveragemonthlyenergyconsumptionof40kWhperpersoninlow-incomeareasofsub-SaharanAfrica(accordingto2014WorldBankdata),atleast5solarpanelswouldbeneededtoproducetherequiredelectricity.

Citiesinlowandmiddle-incomecountries,inparticular,standtobenefitsignificantlyfromtheadoptionofrooftopsolarPVsystems,astheyoftenfacechallengessuchasunreliablegridinfrastructure,highenergycosts,andlimitedaccesstoelectricity.Rooftopsolarhasthreeuniqueattributesthatsetitapartfromotherformsofrenewableenergygeneration:lowcostofenergyproduction,rapiddeployment,anddecentralizedcitizen-drivenadoption.Thistechnologyisgrowingrapidlyinthesecountriesduetoitslowdeploymentcosts,whichcanbetracedbacktothedrasticreductioninsolarpanelpricesoverthepast50years,fromoverUSD100/WtoUSD0.23/W(Figure1.1).

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FIGURE1.1:SOLARPVPRICESFROM1975TO2022

MappingGlobalDeploymentandPotential:

Overthepastdecade,reductioninthedeploymentcostcoupledwithpolicy-driveninitiativeshasledtoarapiduptakeofRooftopSolarPV(RTSPV)globally.Between2006and2018,theinstalledcapacityoftheRTSPVhasgrownfrom2.5GWto213GW-an85-foldincreaseglobally(IEAreport2019).TheInternationalEnergyAgencystatesthat25millionrooftopsaroundtheworldalreadyhavesolarPVinstalled.Togettonetzeroemissions,“thenumberneedstoincreaseto100millionrooftopsby2030and240millionby2050.”Australiahastheworld’shighestshareofrooftopsolarpercapita.Withinstallationsinmorethan30percentofthecountry’shomes,capacityexceeded19GWin2022.Deploymentismovingatspeedinotherregions,too.TheEuropeanUnionaddedmorethan23GWofrooftopsolarin2022.Around16GWofdistributedPVisalreadyoperationalinIndia,whichhasatargettoachieve500GWofinstalledcapacityforelectricitygeneratedfromnon-fossilfuel-basedtechnologiesby2030.InBrazil,distributedPVdeploymentiscloseto17GW.

Joshietal.(2020)analyzed130millionkm2ofgloballandsurfaceareatodemarcate0.2millionkm2ofrooftoparea,whichtogetherrepresent27petawatthoursperyearofelectricitygenerationatcostsrangingbetweenUSD40andUSD280perMWh.Thiswouldsurpassthecombinedelectricityconsumptionoftheworldin2019whichwas22petawatthoursasreportedbyIEA.ThestudyshowsthatIndiaandChinahaveasizablepotentialforrooftopsolarPV,withthelowestdeploymentcosts

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ofthesetechnologies(USD66perMWhinIndiaandUSD68perMWhinChina).Italsostatedthatatagloballevel,nearly40percentofthepotentialcanbeachievedwithaninvestmentequivalentto10percentofthe2015globalGDPvalueofapproximatelyUSD77trillion,andwithaninvestmentequivalentto30percentofthe2015GDPvalue,nearly100percentoftheglobalpotentialcanberealized.

Thisassessmentprovidesasenseofthepotentialglobalscaleofrooftopsolarenergyproduction,thoughitistheoreticalanddoesnotaccountforotherfactors.WhileitisnotfeasibleforeveryrooftoponEarthtohaveasolarinstallation,thestudyhighlightsthesignificantpotentialofrooftopsolartocontributetoglobalenergyneeds.

TounderstandthepracticalPVpowerpotentialinspecificregionsanddetermineitsviability,WorldBank’sEnergySectorManagementAssistanceProgram(ESMAP)calculatedPVoutputineverycountryviathe

GlobalSolarAtlas.3

Figure1.2evaluatesthepracticalsolarPVpotential,whichisthepoweroutputachievablebyatypicalPVsystem(PVOUT).Itsimulatestheconversionoftheavailablesolarresourcetoelectricpowerconsideringtheimpactofairtemperature,terrainhorizon,andalbedo,aswellasmoduletilt,configuration,shading,soiling,andotherfactorsaffectingthesystemperformance.

3GlobalSolarAtlas,aweb-basedtoolcommissionedandfundedbytheEnergySectorManagement

AssistanceProgram(ESMAP),amulti-donortrustfundadministeredbytheWorldBankthatprovidesasummaryofsolarpowerpotentialandsolarresourcesglobally.

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BOX1.2:GLOSSARY

Terrainhorizon:thelineorboundarywheretheEarth'ssurfacemeetsthesky,asseenfromaspecificlocation.Inthecontextofsolarenergy,itisimportantbecausetheterrainhorizoncanobstructthesunatdifferenttimesoftheday,impactingtheamountofsunlightthatreachessolarpanels.

Albedo:theproportionofsunlightthatasurfacereflects,rangingfrom0(noreflection)to1(fullreflection).albedoaffectshowmuchsunlightisreflectedontosolarpanelsfromthegroundornearbysurfaces,whichcaninfluencetheoverallenergyproduction.

Moduletilt:theangleatwhichasolarpanelisinstalledrelativetothehorizontalplane.Thisangleiscrucialbecauseitdeterminestheamountofsunlightthathitsthepaneldirectly.

Kilowatt-hour(kWh):aunitofenergyrepresentingtheproductionof1,000wattsofpoweroveronehour.

Kilowatt-peak(kWp):themaximumoutputpowercapacityofthesolarPVsystemunderstandardtestconditions(STC),whichtypicallyincludeasolarirradianceof1000W/m²,acelltemperatureof25°C,andairmassof1.5.

Megawatt-hour(MWh):aunitofenergythatequalsonemillionwatt-hoursor1,000kilowatt-hours.

Petawatt-hour(pWh):aunitofenergyequivalenttoonebillion(1,000,000,000)kilowatt-hours.PWhisgenerallyusedtodescribeglobalorcontinental-scaleenergyproduction.

PVOUT:theamountofpowergeneratedperunitofinstalledPVcapacityoverthelongterm(thespecificyield),measuredinkilowatthoursperinstalledkilowattpeak(kWh/kWp).

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FIGURE1.2:PRACTICALSOLARPVPOWERPOTENTIAL

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Long-termyearlyaverageofdaily/yearlysummaries(level0)

(source:ESMAP,2020)

Figure1.2displaysPVOUTdistributionregardlessofanylimitationstothedevelopmentandoperationofsolarPVpower.Therefore,thiscanbeconsideredtheLevel0practicalpotential.

Intotal,93percentoftheglobalpopulationlivesincountrieswheretheaveragedailyPVpotentialrangesbetween3.0and5.0kWh/kWp.Thesecountriesincludefiveofthesixmostpopulousnations:China,India,theUnitedStates,Indonesia,andBrazil,alongwith100others,suchasCanada,therestofLatinAmerica,southernEurope,AfricancountriesaroundtheGulfofGuinea,andnationsincentralandsoutheastAsia.

CountrieswithexcellentconditionsforPV,wherelong-termdailyPVOUTaveragesexceed4.5kWh/kWp,areprimarilyintheMiddleEastandNorthAfrica(MENA)regionandSub-SaharanAfrica.Additionally,Afghanistan,Argentina,Australia,Chile,Iran,Mexico,Mongolia,Pakistan,Peru,andmanynationsofthePacificandAtlanticislandsalsoboastsuchfavorableconditions.(ESMAP,2020)

4Theequatorialbelthaslesspotentialduetothefrequentoccurrenceofclouds.Alowerpotentialistypicalforthetemperatezoneduetoalowersunangle,aswellasinIndiaandthepartsofChinawithahigherconcentrationofaerosols.(ESMAP,2020)

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BOX1.3:AVERAGEPVOUTPUTININDIA

InDelhi,India,anelectrifiedhouseholdconsumesabout270kWhofelectricitypermonthonaverage.WithaPVOUTof4kWh/kWp/day,asperWorldBankdata,atypicalresidentialrooftopof30–35squaremeterscanaccommodatea5kWpsolarsystem(asreportedbytheEIAin2015)wouldgenerateapproximately20kWhofelectricityperday.Overamonth,thissystemwouldproducearound600kWh,whichismorethandoubletheaveragehousehold'smonthlyelectricityconsumption.Thisindicatesthatthesystemwouldnotonlymeetthehousehold'senergyneedsbutalsogenerateasignificantsurplusthatcouldpotentiallybefedbackintothegridorstoredforfutureuse.

Multi-FactorPotentialEvaluation

Theabovetwosectionsprovideatheoreticalsenseoftheglobalpotential.However,todeterminetheholisticrooftopPVpotentialforaspecificproject,amulti-factorevaluationisnecessary.Fakhraianetal.(2021)emphasizethat,regardlessofmethodologiesandprojectscales,differentsub-potentialsmustbeidentifiedandanalyzedtofindtheoptimalpointsforthedesiredrooftopphotovoltaicpotential.Figure1.3presentsanoverviewofthesesub-potentials,describedasfollows:

FIGURE1.3ANOVERVIEWOFROOFTOPSOLARPVPOTENTIALESSENTIALFACTORS

Overall

Potential

Sub-

Potentials

Factors

Technical

TransformationalCharacteristics

Costs,

Lifetime&

InterestRates

Solar

RadiationEstimation

ContraintsAnd

Regulations

RooftopSolarPVPotential

GeographicPotential

EconomicPotential

TechnicalPotential

PhysicalPotential

RooftopGeometry

ShadingEffects

Adaptedfrom:E.Fakhraianetal

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a.PhysicalPotential:Thissub-potentialencompassesthemaximumenergylimitoftheresource,whichincludesthetotalsolarenergyreceivedbyurbanareas.Mostfactorsconsideredforsolarradiationestimationarerelatedtometeorologicaldata,suchasmonthlyradiationandmonthlyclearnessindex.

b.GeographicorUrbanPotential:Thissub-potentialevaluatestheimpactofthebuiltenvironmentandlocationconstraints.Itinvolvesidentifyingsuitablerooftopsforinstallingphotovoltaicsbyconsideringfactorslikerooftopgeometry,shadingeffectsfromotherbuildingsandtrees,superstructuresonrooftops,rooftopinclinations,andslopes.

c.TechnicalPotential:Thissub-potentialinvolvestransformingthesolarenergyreceivedbytheavailableroofareaintoelectricalenergybyaccountingfortheefficiencyandperformanceofthesolarphotovoltaictechnologyandlossduetopanelmismatch,dirt,cables,andinverters.Additionally,thespaceneededbetweenphotovoltaicmodulestoavoidshadowingisacrucialaspectofdeterminingthetechnicalpotential.

d.Socio-EconomicandMarketPotential:Foracompleteandrealisticpotentialassessment,thissub-potentialmustbeconsidered.Itincludeseconomicparameterssuchasinstallationcosts,maintenancecosts,installationlifetime,interestrates,operationalcosts,societalconstraints,andgovernmentregulations.Theeconomicattractivenessofrooftopphotovoltaicinstallationsundercurrentmarketconditionsmustbeinvestigatedtodeterminetheprofitabilityofaspecificlocation.Takentogether,thesesub-potentialshighlightthatrooftopsolarisnotaone-size-fits-allsolutionbutratherasizablealternativelow-carbongenerationsourcethatmustundergoamulti-factorevaluationtodetermineitscontextual(oraccurate)rooftopsolarpotential.

2.BenefitsandLimitationsofRooftopSolarEnergy

RooftopsolarPVoffersmultiplebenefitsforlow-andmiddle-incomecountries,especiallybyreducingelectricitycostsandrelianceondieselgenerators.Distributedphotovoltaic(DPV)technologyimprovesaffordabilitywithzerooperatingcostsandminimalmaintenance.Itcanenhanceservicequalitybypoweringmicrogridsthatcanoperateindependently(“islandable”microgrids)whencoupledwithbackupdeviceslikebatterystorage.SinceDPVdoesnotdependonfossilfuels,itenhancesenergysecurityandresiliencetoeconomicshocksfromvolatilefuelprices.

Installedontherooftopsofresidential,commercial,orindustrialbuildings,rooftopPVsystemsnotonlyofferasustainablepowersourcebutalsoyieldsignificantsocio-economicbenefits.Thesesystemsallowforelectricitygeneratedtobeeitherusedforself-consumption,enhancingenergyindependence,orfedbackintothegrid,therebysupportingbroadercommunityenergyneeds.Typically,thepaybackperiodforasolarrooftopprojectcanvary,butmanysystemscanpayforthemselveswithin6to10yearsdependingonsystemcosts,estimatedenergysavings,andavailablesolarincentives(ForbesHome,2024).

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Inthecontextofenergytransitions,DPVcanbenefitbroadersocietythroughjobcreation,inclusiveeconomicgrowth,andincreasedconsumerownershipandchoiceoverenergysupply.Additionally,theyreducetheuseofpollutingfuelsbenefitshumanhealthandthelocalenvironment.

Installedontherooftopsofresidential,commercial,orindustrialbuildings,rooftopPVsystemsnotonlyofferasustainablepowersourcebutalsoyieldsignificantsocio-economicbenefits,particularlyvaluableinlowandmiddle-incomecountries.Thesesystemsallowforelectricitygeneratedtobeeitherusedforself-consumption,enhancingenergyindependence,orfedbackintothegrid,therebysupportingbroadercommunityenergyneeds.Thissectiondelvesintothearrayofbenefitsthatrooftopsolarsystemsintroduceatvariouslevels,asillustratedinFigure2.1.

FIGURE2.1ROOFTOPPVBENEFITSATVARIOUSLEVELS

ConsumerLevel

•Reductioninelectricitybills

•Energyindependence

•Decarbonizingbuildingfootprint

•Resilienceagainst

blackouts/brownoutsandclimatehazards

•Healthbenefitsduringheatstress

•Increasespropertyvalue

•Taxincentives

City/MunicipalLevel

•ParisAlignment

•CompliancewithSDG7

•Localemploymentgeneration

•NorequirementofadditionalLand

•Reducesneedfor

additionaltransmissionInfrastructure

•Scalableinitiative

UtilityLevel

•Reducespeakdaydemand

•ReducesOperationalCosts

•Reduces

transmissionanddistributionLosses

•4.Opportunitiesfornewrevenue

streams

RooftopSolarPVBenefits

Simultaneously,itisimportanttoconsidertheinherentlimitationsandchallengesthatmustbeacknowledgedindiversegeographicandeconomiccontexts,whichcanhindertheviabilityofrooftopsolarsystems.

Urbanform:Thereisagrowingglobalconsensusthat,whilesolarPVsystemsareincreasinglyeconomicallyviable,theirexpansiondependsontheextenttowhichtheycanbeintegratedintothebuiltenvironment.Mohajerietal.(2016)foundaninverserelationshipbetweenurbancompactnessandsolarenergypotentialinthatsolarpotentialtendstodecreaseasurbancompactnessincreases,duetoovershadowingeffectsfromthegroundandneighboringbuildings.Akrofietal(2023)further

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conductedresearchtostudyrooftoppotentialin3differentclassesofneighborhoodsinGhanaandfoundthatthelow-incomeneighborhoodexhibitedhigherdensitywithclusteredbuildingpatternsand,consequently,lowerrooftopPVpotential.Therefore,itisessentialforcitygovernmentstocarefullyanalyzetheurbancontextbeforedeployingrooftopsolarPVsystemstoensuretheyachievetheirmaximumpotentialandremaineconomicallyviable.Zhangetal.(2019)concludedthaturbandesignsignificantlyaffectssolarenergypotentialandenergyefficiencyinbuildings,notingthatsolarenergypotentialcouldbeincreasedby200percentbyappropriatelydesigningurbanblocktypologies.

Seasonality:TheSeasonalityIndex,developedbytheEnergySectorManagementAssistanceProgram(ESMAP),measuresthevariabilityofsolarenergyproductionthroughouttheyearbycomparingthehighesttothelowestmonthlysolarenergytotals.Alowerindex(below2)indicatesconsistentsolaroutput

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,whileahigherindexpointstogreatervariability,affectingthereliabilityofsolarsystems.InferringfromESMAP’s2020SeasonalityIndexmap,theSiberianregion,Scandinaviancountries,northernpartsoftheU.S.andCanada,aswellaslowandmiddleincomecountrieslikeNepal,Mongolia,Bhutan,Kyrgyzstan,Tajikistan,andArmeniaexperiencesignificantseasonalvariations.Whilesummermonthsshowhighsolarpotential,winterpresentschallengeswithshorterdaysandlowersolarangles,reducingsolarpowereffectiveness.TheSeasonalityIndexiscrucialforpolicymakersandinvestorsinassessingtheviabilityofsolarprojects,guidingdecisionsonimplementingtechnologiesthataccommodatelocalclimateimpacts.

Regulatoryconstraintsandmaintenancecosts:Inmanyurbanareas,thepotentialforrooftopsolarinstallationsislimitedduetovariousfactorssuchasarchitecturalstyles,existinginfrastructurelikeHVACsystems,andregulatoryconstraints,particularlyinhistoricdistricts.Additionally,thelogisticalcomplexitiesandhighcostsassociatedwithinstallingandmaintainingrooftopsolarsystemsindenseurbanenvironmentsposesignificantchallenges.Regulatoryconstraints,especiallyinhistoricdistricts,canlimitorprohibitthemodificationsneededforrooftopsolarinstallations(Webb,A.2017).

Multi-ownershipandtenancybarriers:Multi-ownedbuildingsandrentalpropertiespresentadditionalbarriersduetothecomplexitiesofcoordinatingamongmultipleownersandtenants.Thesecomplexitiesoftenleadtoownershipdisagreementsandsocialdisputes,makingitchallengingtoequitablydistributethebenefitsofrooftopsolarsystems.AccordingtoPoshnathetal.(2023),theadoptionofRenewableEnergySystems(RES)insuchsettingsishinderedbyenergyandbenefitallocationconcerns.Theirstudyhighlightstheneedforpoliciesthataddressenergyownershipandlandadministrationaspectstofacilitatetheefficientandequitableadoptionofrooftopsolarinmulti-ownedbuildings.

5Intotal,86percentoftheglobalpopulationlivesin150countrieswheretheaverageseasonalityindexisbelow2.0,andPVOUTexceeds3.5kWh/kWp.(ESMAP.2020.GlobalPhotovoltaicPowerPotentialby

Country:WorldBank.)

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Inthecasesdiscussedabove,off-siteutility-scalesolarorotherrenewableenergyproductionmethodscouldbeutilizedasviablealternativestomeetthecity'srenewableenergygoalsefficientlyandequitably.

Whilethisnoteprimarilyfocusesonencouragingthedevelopmentofrooftopsolarincitieswhereitsadoptionhasbeenlimited,itisalsoimportanttonotepotentialchallengesthatcouldarisefromrapiddeploymentofsolarPV.Theseincludelossofrevenueforutilities,difficultiesincostrecoveryfornetworkmaintenance,andissuessuchasexcessiveloadorcurtailmentinareaswheresolarrooftopinstallationsinjectmorepowerthanthelocalgridcanabsorb.Literatureonthesechallengesremainslimitedatthisstage.

3.SpecificUseCasesofSolarRooftopforL&MICs

Inlow-andmiddle-incomecountries(L&MICs),thedeploymentofdistributedphotovoltaics(DPV)addressesfrequentgridinterruptionsduetoinadequatepowergeneration,weaktransmissionanddistributionnetworks,andfinancialstrugglesofutilities.TheWorldBankESMAP's“FromSuntoRooftoGrid"series

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identifiesnineDPVdeploymenttypes,or"usecases,"thatprovidedistinctsolutionstothesechallenges,oftenincombinationwithotherdistributedenergyresourceslikebatteriesandmicrogrids.Asshowninthefigure3.1,thenineusecasescovervariousscenarios,fromwell-establishedapplicationstoemergingopportunities,eachdesignedtoreduceemissionsandimproveenergyreliability.Thefigurealsoillustrateshowtheseusecasesimpactutilitiesandinvolvevariousstakeholders,suchasconsumers,distributioncompanies,andgovernmentagencies,focusingonaddressingoperationalinefficienciesandfinancialweaknessesinthepowersector.Eachusecaseisthenbrieflyintroducedwiththedeploymentdriver,feed-inarrangements(referBox3.1),impactonutilities,potentialfinancingstructures,andreal-lifeexamplesofcity-levelprojectsthatillustratetherangeofapplicationsandpotentialofsolarPV.

6The"FromSuntoRooftoGrid"seriesbyESMAPcoversdistributedphotovoltaics(DPV)andincludesthreereports:DPVinEnergySectorStrategies(2021),GridOperationandPlanningwithDPV(2023),andDPV

EconomicsandPolicy(2024).

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FIGURE3.1:DPVUSECASES,THEIRPREVALENCE

7,

DRIVINGAGENTS&ASSOCIATEDIMPACTSONUTILITIES

Source:DPVinEnergySectorStrategies,ESMAP(2021)

7Common:Usecasesthatarewellestablishedintheirdeployment

Emerging:UsecasesthathavebeendeployedinafewcircumstancesOpportunity:Usescasethatareyettobedeployedwidely

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BOX3.1:FEED-INARRANGEMENTS

Feed-all:Inthisarrangement,allsolarPVoutputisfedintothegrid.

Feed-some:Inthismodel,someofthepowerisconsumedon-siteorstoredforlateruse,whiletheexcessisfedintothegrid.Feed-somemodelsmayinvolveasingle(bidirectional)“netmeter”thatmeasuresthenetflowofpowertoorfromthegrid,ortwo(unidirectional)“grossmeters,”oneforeachdirectionofpowerflow.

Feed-none:Here,allthegeneratedpowerisconsumedon-sitebytheuser,withnoexcesssenttothegrid.Metersmaybeused