光伏系統(tǒng)工具書

SolarPhotovoltaic(PV)Systems

weshapeasafe,highqualitysustainableandfriendlybuiltenvironment.

Contents

1SolarPhotovoltaic(“PV”)Systems–AnOverview4

1.1Introduction4

1.2TypesofSolarPVSystem5

1.3SolarPVTechnology6

●crystallinesiliconandThinFilmTechnologies8

●conversionEf?ciency8

●EffectsofTemperature9

1.4TechnicalInformation10

2SolarPVSystemsonaBuilding12

2.1Introduction12

2.2InstallationAngle12

2°3AvoidshadingPvModules13

2°4AestheticandcreativeApproachesinMountingPvModules14

2°5solarPvoutputPro?le14

2.6SolarPVYield15

2°7costofasolarPvsystem15

3AppointingaSolarPVSystemContractor16

3.1Introduction16

3.2GettingStarted17

●GetanExperiencedandLicensedcontractor17

●choosingBetweenBids17

●solarPvsystemwarranty17

●RegularMaintenance19

●otherRelevantMatters19

4SolarPVSystemInstallationRequirements20

4°1ElectricallnstallationLicence20

4°2ElectricalsafetystandardsandRequirements20

4°3ApplicationofElectricallnstallationLicence21

4°4conservationandDevelopmentcontrolRequirements21

4°5GuidelinesonconservationandDevelopmentcontrol21

4°6structuralsafetyandLightningProtection22

●structuralsafety22

●LightningProtection22

4°7connectiontothePowerGrid22

4°8GetconnectedtothePowerGrid23

4°9saleofsolarPvElectricity23

4°10Designandlnstallationchecklist27

5OperationsandMaintenance28

5°1operationsofsolarPvsystems28

5°2RecommendedPreventiveMaintenanceworks29

Appendices

APPENDIXA–EXAMPLESOFSOLARPVSYSTEMONBUILDINGSIN

SINGAPORE

A°1ZEROENERGYBulLDlNG@BCAACADEMY32

A.2POHERNSHlH(TEMPLEOFTHANKSGlvlNG)34

A.3313SOMERSETCENTRAL36

A.4SENTOSACOvE38

A.5MARlNABARRAGE40

A.6LONZABlOLOGlCS42

A.7ZEROENERGYHOuSE44

A°8TAMPlNESGRANDE46

A°9HDBAPARTMENTBLOCKSATSERANGOONNORTHPREClNCT48

A.10HDBAPARTMENTBLOCKSATWELLlNGTONClRCLEPREClNCT50

APPENDIXB

B°1ENGAGlNGALlCENSEDELECTRlCALWORKER52

APPENDIXC

C°1CONTACTlNFORMATlON54

APPENDIXD–INCENTIVESFORSOLARPVSYSTEM

D°1SOLARCAPABlLlTYSCHEME(SCS)55

D°2MARKETDEvELOPMENTFuND(MDF)56

D°3GREENMARKSCHEME57

D°4GREENMARKGROSSFLOORAREA(GM-GFA)lNCENTlvESCHEME58

D°5$100MlLLlONGREENMARKlNCENTlvESCHEME59

FORExlSTlNGBulLDlNGS(GMlS-EB)

D°6ENHANCED$20MlLLlONGREENMARKlNCENTlvESCHEMEFOR60

NEWBulLDlNGS(GMlS-NB)

1

Foreword

cognizantofthegrowingpopularityofsolarphotovoltaic(pv)installationsamongstresidentialdwellersaswellasbuildingdevelopers,andthecorrespondingdemandforacomprehensivesetoftechnicalandregulatoryinformation,theEnergyMarketAuthority(EMA)andtheBuildingconstructionAuthority(BcA)gottogetherearlierthisyeartoworkonintegratingtheirrespectivesolarmanualsintoanall-in-onereferenceguideforthosewhoarekeenoninstallingsolarpvsystemsinSingapore.

Theoutcomeofthisjointproject,whichalsosawtheinvolvementofindustrypartnersandstakeholderssuchasphoenixsolarpteLtd,GrenzonepteLtd,solarEnergyResearchlnstituteofsingapore(sERls)andsingaporepolytechnic,isthis“Handbookforsolarphotovoltaic(pv)systems”°Throughthisintegratedandrevisedhandbook,wehopetobeabletoprovideacomprehensiveguidetotherelevantparties,includingowners,developers,engineers,architects,LicensedElectricalworkersandelectriciansonthekeyissues,requirementsandprocessespertainingtotheinstallationofsolarPVsystems.

Aswiththepreviouseditionofthehandbooks,thissinglevolumecoversandprovidesinformationonlicensing,marketandtechnicalrequirements,andbuildingandstructuralissuesthatarerelatedtotheimplementationofsolarpvsystemsinabuildingenvironment°lnaddition,itprovidesnewinformationontheinstallationrequirementsforsolarpvsystems,operationsandrecommendedpreventivemaintenanceworks,andvariousincentivestopromotesolarpvsystemsinsingapore°wehavealsorefreshedthepresentationofthehandbooktomakeitmoreaccessibleandreader-friendly,aswellastoincorporateexamplesofcompletedsolarpvinstallationsinsingapore°

wehopeyouwill?ndthistobeausefulguide°

DavidTan

DeputyChiefExecutive

EnergyplanningandDevelopmentDivisionEnergyMarketAuthority

AngKianSeng

Director

centreofsustainableBuilding&constructionBuildingandconstructionAuthority

2

Acknowledgements

wewouldliketothankthefollowingorganisationsfortheirsupportandcontributionsinthedevelopmentofthishandbook:

1)GrenzonepteLtd

2)phoenixsolarpteLtd

3)singaporepolytechnic

4)solarEnergyResearchlnstituteofsingapore(sERls)

5)sppowerGrid

6)urbanRedevelopmentAuthority

Note

PleasenotethatsomeoftheinformationinthesolarPVhandbookmaybesuperseded.YoumaywishtorefertothesolarPVportal.sg/solarpvforupdatedinformation.

3

1

SolarPhotovoltaic(“PV”)Systems–AnOverview

1.1Introduction

Thesundeliversitsenergytousintwomainforms:heatandlight°Therearetwomaintypesofsolarpowersystems,namely,solarthermalsystemsthattrapheattowarmupwater,andsolarPvsystemsthatconvertsunlightdirectlyintoelectricityasshowninFigure1°

Figure1.ThedifferencebetweensolarthermalandsolarPVsystems

whenthePvmodulesareexposedtosunlight,theygeneratedirectcurrent(“DC”)electricity°AninverterthenconvertstheDCintoalternatingcurrent(“AC”)electricity,sothatitcanfeedintooneofthebuilding,sACdistributionboards(“ACDB”)withoutaffectingthequalityofpowersupply°

4

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

1.2TypesofSolarPVSystem

solarPvsystemscanbeclassi?edbasedontheend-useapplicationofthetechnology°TherearetwomaintypesofsolarPvsystems:grid-connected(orgrid-tied)andoff-grid(orstandalone)solarPvsystems°

Grid-connectedsolarPvsystems

ThemainapplicationofsolarPvinsingaporeisgrid-connected,assingapore,smainislandiswellcoveredbythenationalpowergrid°MostsolarPvsystemsareinstalledonbuildingsormountedonthegroundiflandisnotaconstraint°Forbuildings,theyareeithermountedontherooforintegratedintothebuilding°ThelatterisalsoknownasBuildinglntegratedPhotovoltaics(“BlPv”)°withBlPv,thePvmoduleusuallydisplacesanotherbuildingcomponent,e°g°windowglassorroof/wallcladding,therebyservingadualpurposeandoffsettingsomecosts.

Thecon?gurationofagrid-connectedsolarPvsystemisshowninFigure2°

Figure2.Grid-connectedsolarPVsystemcon?guration

Abuildinghastwoparallelpowersupplies,onefromthesolarPvsystemandtheotherfromthepowergrid°ThecombinedpowersupplyfeedsalltheloadsconnectedtothemainACDB°

TheratioofsolarPvsupplytopowergridsupplyvaries,dependingonthesizeofthesolarPvsystem°wheneverthesolarPvsupplyexceedsthebuilding,sdemand,excesselectricitywillbeexportedintothegrid°whenthereisnosunlighttogeneratePvelectricityatnight,thepowergridwillsupplyallofthebuilding,sdemand°

5

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

Agrid-connectedsystemcanbeaneffectivewaytoreduceyourdependenceonutilitypower,increaserenewableenergyproduction,andimprovetheenvironment°

off-gridsolarPvsystems

off-gridsolarPvsystemsareapplicableforareaswithoutpowergrid°currently,suchsolarPvsystemsareusuallyinstalledatisolatedsiteswherethepowergridisfaraway,suchasruralareasoroff-shoreislands°Buttheymayalsobeinstalledwithinthecityinsituationswhereitisinconvenientortoocostlytotapelectricityfromthepowergrid°Forexample,insingapore,severalURAparkingsignlightsarepoweredbyoff-gridsolarPVsystems.

Anoff-gridsolarPvsystemneedsdeepcyclerechargeablebatteriessuchaslead-acid,nickel-cadmiumorlithium-ionbatteriestostoreelectricityforuseunderconditionswherethereislittleornooutputfromthesolarPvsystem,suchasduringthenight,asshowninFigure3below°

Figure3.Off-gridsolarPVsystemcon?guration

1.3SolarPVTechnology

ThissectiongivesabriefdescriptionofthesolarPvtechnologyandthecommontechnicaltermsused.

AsolarPvsystemispoweredbymanycrystallineorthin?lmPvmodules°lndividualPVcellsareinterconnectedtoformaPVmodule.Thistakestheformofapanelforeasyinstallation.

6

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

Mono-CrystallineSiliconPVCellPoly-CrystallineSiliconPVCell

Figure4.Mono-andPoly-CrystallineSiliconPVCell

Pvcellsaremadeoflight-sensitivesemiconductormaterialsthatusephotonstodislodgeelectronstodriveanelectriccurrent°TherearetwobroadcategoriesoftechnologyusedforPvcells,namely,crystallinesilicon,asshowninFigure4whichaccountsforthemajorityofPvcellproduction;andthin?lm,whichisnewerandgrowinginpopularity°The“familytree”inFigure5givesanoverviewofthesetechnologiesavailabletodayandFigure6illustratessomeofthesetechnologies°

Commercially

availableproduct,

suitableforSingapore

R&Dorpilotstage,or

unsuitablefor

Singapore

CrystallineSilicon(waferbased)

Special

Compoundeg

semiconductorGaAs-based

CIGS

(CopperIndiumGallium

Selenide)

CdTe

(CadmiumTelluride)

Dye-sensitised(TiO2)

PVCellTypes

Thin

Film

Poly-crystalline

Amorphous-Si

(a-Si)

Mono-crystalline

Tandem

a-Si/microcrystalline

Figure5.PVtechnologyfamilytree

7

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

Mono-crystallinePoly-crystallineFlexibleamorphousCIGSthin?lm

siliconsiliconthin?lm

Figure6.CommonPVmoduletechnologies

crystallinesiliconandThinFilmTechnologies

crystallinecellsaremadefromultra-puresiliconrawmaterialsuchasthoseusedinsemiconductorchips°Theyusesiliconwafersthataretypically150-200microns(one?fthofamillimetre)thick°

Thin?lmismadebydepositinglayersofsemiconductormaterialbarely0°3to2micrometresthickontoglassorstainlesssteelsubstrates.Asthesemiconductorlayersaresothin,thecostsofrawmaterialaremuchlowerthanthecapitalequipmentandprocessingcosts.

conversionEf?ciency

TechnologyModuleEf?ciency

Mono-crystallinesilicon

12°5-15%

Poly-crystallinesilicon

11-14%

copperlndiumGalliumselenide(clGs)

10-13%

cadmiumTelluride(cdTe)

9-12%

Amorphoussilicon(a-si)

5-7%

Table1.Conversionef?cienciesofvariousPVmoduletechnologies

Apartfromaestheticdifferences,themostobviousdifferenceamongstPvcelltechnologiesisinitsconversionef?ciency,assummarisedinTable1°

Forexample,athin?lmamorphoussiliconPvarraywillneedclosetotwicethespaceofacrystallinesiliconPvarraybecauseitsmoduleef?ciencyishalved,forthesamenominalcapacityunderstandardTestconditions1(sTc)rating°

1standardTestconditionsrefertothefollowingtestingconditions:

●1,000w/m2ofsunlight

●250ccelltemperature

●spectrumatairmassof1°5

8

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

ForcrystallinesiliconPvmodules,themoduleef?ciencyislowercomparedtothesumofthecomponentcellef?ciencyduetothepresenceofgapsbetweenthecellsandtheborderaroundthecircuiti°e°,wastedspacethatdoesnotgenerateanypowerhencelowertotalef?ciency°

EffectsofTemperature

AnotherimportantdifferentiatorinsolarPvperformance,especiallyinhotclimates,isthetemperaturecoef?cientofpower°Pvcellperformancedeclinesascelltemperaturerises.

Forexample,inbrightsunlight,celltemperaturesinsingaporecanreachover70QC,whereasPvmodulesareratedatacelltemperatureof25QC°Thelossinpoweroutputat70QCisthereforemeasuredas(70-25)xtemperaturecoef?cient°

Mostthin?lmtechnologieshavealowernegativetemperaturecoef?cientcomparedtocrystallinetechnologies°lnotherwords,theytendtoloselessoftheirratedcapacityastemperaturerises°Hence,undersingapore,sclimaticcondition,thin?lmtechnologieswillgenerate5-10%moreelectricityperyear°

APvmoduledatasheetshouldspecifythetemperaturecoef?cient°seeTable2andchartinFigure7°

TechnologyTemperatureCoef?cient

[%/°C]

Crystallinesilicon

-0°4to-0°5

ClGs

-0°32to-0°36

CdTe

-0°25

a-si

-0°21

Table2.Temperaturecoef?cientofvariousPVcelltechnologes

moduleoutputrelativetosTC

Figure7.Theeffectsofanegativetemperaturecoef?cientofpoweronPVmoduleperformance

9

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

ThePvmodulesarenextconnectedinseriesintoaPvstringasshowninFigure8°APvarrayasshowninFigure9isformedbytheparallelaggregationofPvstrings°

Figure8.PVStringFigure9.PVArray

1.4TechnicalInformation

single-core,doubleisolatedsheathedcablesthatcanwithstandtheenvironmentalconditions,andminimisetheriskofearthfaultsandshortcircuitsareusedtointerconnectthePvstringsandarrays°ThecableconnectionsareprotectedinenclosuresknownasjunctionboxthatprovidesthenecessaryconnectorsasshowninFigure10°

Figure10.JunctionBox

ElectricityproducedbythesolarPvinstallationisintheformofDC°TheoutputofthePvinstallationisconnectedthroughtheDCmaincablestotheDCterminalsofthePvinverterwhereelectricityisconvertedfromDCintoAC°

Afterconversion,theACcurrentofthePvinverterisconnectedthroughPvsupplycabletothebuilding,selectricalinstallation(ACdistributionboard)°

Figure11showsatypicalPvinverterconnectedtotheelectricalinstallationofabuilding°Notethattheactualcon?gurationofthePvinvertermayvaryacrossdifferentsystems.

10

Chapter1

SOLARPHOTOVOLTAIC(“PV”)SYSTEMS–ANOVERVIEW

DCSide

ACSide

PV

Inverter

ACDistributionBoard

PVDCMainCable

PVSupplyCable

Figure11.TypicalPVinverterconnectedtoa

building’selectricalinstallation

Justlikeanyelectricalinstallationinabuilding,earthingisanimportantsafetyrequirementforsolarPVsystem.ArrangementmustbemadeforproperconnectionofthesolarPVsystemtotheconsumer’selectricalinstallationearthingsystem.

lnlocationssusceptibletolightningstrikes,alightningprotectionsystemmustbeprovided,andalltheexposedmetallicstructuresofthesolarPvsystemmustbeboundtothelightningearthingsystem.

ltistheresponsibilityoftheconsumerstohavetheirsolarPvsystemsmaintainedregularlytoensuresafeoperationoftheirsolarPVsystemsandelectricalinstallations.seeFigure12foradiagramshowingthesolarPvsystemformingpartofaconsumer,selectricalinstallation.

Figure12.SolarPVsystemformingpartofaconsumer’selectricalinstallation11

2

SolarPVSystemsonaBuilding

2.1Introduction

TherearemanyexamplesoverseaswherePvmodulesaremountedontheroofandintegratedintobuildingfa§ades°TheyworkparticularlywellinEuropeandNorthAmerica,assouth-facingfa§adesintheseregionsarewellexposedtothesun°

lnsingapore,wehavetoconsiderthatthesunpassesalmostdirectlyoverhead°ThisisbecausewearelocatedneartheEquator,andthepathofthesunfollowstheEquator,withseasonalvariationsofupto23°5otothenorthorsouth.ThereforethereareoptimalpositionstolocatethePvmodulesthathavetobetakenintoconsideration°RefertoAppendixAforexamplesofsolarPvsystemsonbuildingsinsingapore°

2.2InstallationAngle

Tomaximiseelectricityproductionforuseinsingapore,thebestlocationforthePvmodulestobeinstalledisrightontopofabuilding,facingthesky°ThepossibleinstallationoptionsareshowninFigure13°

Figure13.WheretoinstallPVmodulesonabuildinginSingapore

12

Chapter2

SOLARPVSYSTEMSONABUILDING

Verticalfa?adesandsteeplyslopedroofstendtosufferabiglossintheabilitytogenerateelectricityinexchangeforhigherpublicvisibility°

withthePvmodulesfacingthesky,itispossibletoimprovetheyieldbyinstallingPvmodulesontrackerstofollowthesunfromeasttowestduringtheday(single-axistrackers),andfromnorthtosouthduringseasonalchanges(dual-axistrackers)°

However,trackerscanonlyimprovesystemperformanceunderdirectsunshine,andtheygivenoadvantageindiffusedsunlightconditions,suchasoncloudyorhazydays°

Thedownsideofhavinglat-mountedPvmodulesisthattheytendtogetdirtyfromrainwateranddust°seeFigure14°ltisthereforebettertomountthePvmodulesatanincline(10-15oforframedmodules,oraslittleas3-5oforunframedmodules),toallowrainwatertoproperlydrainoff

Figure14.PVmoduleframestrapdirtaswaterevaporatesfroma

?at-mountedPVmodule

2.3AvoidShadingPVModules

PVmodulesshouldbefreefromshade.ShadingofanysinglecellofacrystallinesiliconPvmodulewilldrasticallyreducetheoutputoftheentirePvmodule°

Thin?lmPvmodulesaremoretoleranttopartialshadingthancrystallinesiliconPvmodules°Typicalculpritsincludeshadowscastbytalltreesandneighbouringbuildings°

13

Chapter2

SOLARPVSYSTEMSONABUILDING

2.4AestheticandCreativeApproachesinMountingPVModules

BesidesmountingPvmodulesontherooftop,customisedPvmodulescanbeintegratedintothebuildingfa§adeinacreative,aestheticallypleasingmanner°Theycanbemountedonanypartoftherooftoporexternalwallsthatiswellexposedtosunlighte°g°skylights,cladding,windows,andexternalshadingdevices°

Theycanalsobeintegratedintoexternalstructuressuchasfa§adesandcanopies,asshowninFigure15andFigure16,respectively°

Figure15.BIPVmodulesintegrated

intoafa?ade

Figure16.BIPVmodulesintegratedintoa

skylightcanopy

2.5SolarPVOutputPro?le

solarPvonlyproduceselectricitywhensunlightisavailable°TheoutputofasolarPvsystemvarieswithitsratedoutput,temperature,weatherconditions,andtimeoftheday°Thepoweroutputpro?leofthePvinstallationasshowninFigure17,ataselectedtestsiteinsingaporecollectedoveraperiodfrom2002-2004,intermsofitscapacityfactor2,showsahighvariationofsolarPvoutput°

[2]PVOutputcapacityfactor=RatiooftheactualoutputofthePVinstallationattime(t)overitsoutputifithadoperatedatfullratedoutput.

14

Chapter2

SOLARPVSYSTEMSONABUILDING

PVoutputcapacityfactor

Figure17.Varyingdailypoweroutputpro?leofPVinstallation

ataselectedtestsiteinSingapore

2.6SolarPVYield

TheamountofelectricityyouareabletogeneratefromasolarPVsystemdependsnotonlyontheavailabilityofsunshinebutalsoonthetechnologyyouchoosetoinstall°Forexample,atypical10-kwrooftopsolarPvsysteminsingaporewouldproduceabout11,000to12,500kwhannuallyusingcrystallinePvmodules,and12,000to14,500kwhannuallywithamorphoussiliconthin?lmPvmodules°

2.7CostofaSolarPVSystem

ThecostofyoursolarPvsystemwilldependonmanyfactors:systemcon?guration,equipmentoptions,labourcostand?nancingcost°Pricesalsovarydependingonfactorssuchaswhetherornotyourhomeisnew,andwhetherthePvmodulesareintegratedintotherooformountedontheroof°Thecostalsodependsonthesystemsizeorrating,andtheamountofelectricityitproduces°

Generally,solarPvsystemsentailhighcapitalcosts°withsolarpower,youcansaveonthepurchaseofelectricityfromthegrid°Butevenwiththesesavings,itwilltakealongtimetorecoverthecapitalcostofthesolarPvinstallation°TheoperatingcostsforsolarPvinstallationsarenegligible,buttheannualmaintenancecostbeyondthewarrantyperiodmayamountto0°5%to1%ofthecapitalcostoftheinstallation°

Thereforeonanoverallbasis,solarPv-derivedelectricityisstillmuchmoreexpensivethanthatfromthepowergrid°However,thecostofsolarPvhashistoricallybeenfallingbyabout4%ayear,andifthiscontinues,solarPvmaybecompetitivewithinthenext10years°ForincentivesonsolarPvsystem,pleaserefertoAppendixD°

15

3

Appointinga

SolarPVSystemContractor

3.1Introduction

YouwillneedtoselectacontractortoinstallyoursolarPvsystem°lfinterested,youmaycheckwiththefollowingorganisationsforsomesolarPvsystemdesignersandcontractors:

●TheListofsolarPvsystemcompaniesinsingapore,availablefromsustainableEnergyAssociationofsingapore,bycalling63388578orbyvisiting

http://www°seas°org°sg/about-seas/our-committees/cleanenergy/54

●ThesingaporesustainableDevelopmentlndustryDirectory2008/2009,availablefromthesingaporeBusinessFederation,bycalling68276838orbyvisiting

http://www°sbf°org°sg/public/publications/industrydirectory°jsp

YourcontractorwillappointaLicensedElectricalWorker(“LEW”)whowillberesponsibleforthedesign,installation,testing,commissioning,andmaintenanceofyoursolarPvsystem.

lnthecaseofnon-residentialelectricalinstallationsthatrequireanelectricalinstallationlicence,theappointedLEWwhosupervisestheelectricalwork(“DesignLEW”)maynotbetheonewhotakeschargeofyourelectricalinstallation(“l(fā)nstallationLEW”)°TheDesignLEWwillthenhavetoworkwiththelnstallationLEWtoworkoutthetechnicalissues.

PleaserefertoAppendixBfordetailsonhowyoucanengageanLEWandthenecessaryconsultationprocess.

16

Chapter3

APPOINTINGASOLARPVSYSTEMCONTRACTOR

3.2GettingStarted

First,compilealistof