Fire Codes and NFPA 855 for Energy Storage Systems

The ESS project that led to the first edition of NFPA 855, the Standard for the Installation of Stationary Energy Storage Systems (released in ... Home SystemDesign&Engineering ContentStrategy&Production Education&Training ProjectPortfolio AboutUs Team Contact Resources Blog ContactUs Beforedivingintothespecificsofenergystoragesystem(ESS)firecodes,itiscrucialtounderstandwhybuildingandfirecodesaresorelevanttothesuccessofourindustry.Thesolarindustryisexperiencingasteadyandsignificantincreaseininterestinenergystoragesystemsandtheirdeployment.Decreasinglithium-ionbatterycostsandincreasingdemandforcommercialandresidentialbackuppowersystemsaretwokeyfactorsdrivingthisgrowth.Unfortunately,asthesolar-plus-storageindustryhasquicklyrampeduptomeettheincreaseddemand,somenotableeventshaveoccurred,includingfirescausedbybatterycellfailuresandevenahigh-profileexplosion.Inthespringof2019,adefectivebatterycellshort-circuitedandcaughtfireata2MWESSinstalledforArizonaPublicService(APS).Thefirespreadtohundredsofadjacentcells,resultinginanexplosivegasbuild-upintheESSstoragecontainer.Apowerfulexplosionoccurredwhenfirstrespondersarrivedon-siteandopenedthecontainer.Nineofthoseindividualsrequiredhospitalization,fourwithseriousinjuries.SeeNFPAJournalfall2021editionforanin-deptharticlecoveringthisevent. TherehavealsobeenissuesintheU.S.residentialenergystoragesector.Forexample,afterfivereportedfiresstemmingfromitsRESU10batteryunits,LGChemissuedproductrecallsinDecemberof2020andagaininAugust2021.AccordingtotheConsumerProductSafetyCommission,thesefiresresultedinpropertydamageandoneinjury.UnfortunateeventslikethesedrivehometheimportanceofprioritizingsafetyinESSdesign,componentprocurement,andmanufacturingaswellasthedesign,deployment,andO&Moffieldedsystems.NewandupdatedESScodesandstandardsresultfromtheevolvingefforttosafeguardagainstthehazardsposedbymanufacturingdefectsandsystemdesignandinstallationerrors.Theconstantdriveforcostreductionacrosstheindustrycanresultinsubstandardequipmententeringthesupplychainanddesignandinstallationshortcuts.FirecodesandstandardsinformESSdesignandinstallationandserveasabackstoptoprotecthomes,families,commercialfacilities,andpersonnel,includingoursolar-plus-storagebusinesses.Code-makingpanelsdevelopthesecodesandstandardswithtwoprimarygoalsinmind:(1)reducingthelikelihoodoffirestemmingfromenergystorageequipment,and(2)minimizingpropertydamageandpersonalinjuryshouldafireoccur.IFC,IRC,IBC,andNFPA1Buildingandfirecodesprovideminimumrequirementsforthehealthandsafetyoftheoccupants,andthepublic,innewandexistingbuildingsandstructures.Internationalcodes(I-Codes)aredevelopedbytheInternationalCodeCouncilandprovideabasecodestandardforlocalgovernmentstoadoptandmodifyasnecessary.CommercialbuildingsaresubjecttotheInternationalBuildingCode(IBC)andtheInternationalFireCode(IFC),whileone-andtwo-familydwellingsfollowtheInternationalResidentialCode(IRC).Anauthorityhavingjurisdiction(AHJ),suchascityorcountygovernment,oftenadoptsthesecodesintheirentirety.However,itisimportanttonoteAHJsfrequentlyadjustthemtomeettheuniqueneedsoftheirjurisdictions.MostPVsystemdesignersandinstallersareintimatelyfamiliarwithlocalbuildingandfirecodesthataddressthesealingandflashingofrooftopPVarraypenetrations,structuralandseismicloading,windandfireresistance,firefighteraccess,andmarkingandlabelingrequirements.However,manydesignersandinstallers,especiallythosenewtoenergystoragesystems,areunfamiliarwiththefireandbuildingcodespertainingtobatteryinstallations. Anothercode-makingbodyistheNationalFireProtectionAssociation(NFPA).SomestatesadopttheNFPA1FireCoderatherthantheIFC.BecausetheNFPAdirectsandoverseestheNationalElectricalCode,NFPA1,andNFPA855,thereisoftenaclosecorrelationinthelanguagebetweenthesedocuments.YoucandownloadI-Codes,publishedbytheInternationalCodeCouncilforspecificlocations.Thesite’sleft-handmenuallowsyoutonavigatecurrentcodesbystate(and,insomeinstances,city).YoucanalsousetheNFPACodefindertoolforNFPA1states.NFPA1andIFCcodecycleadoptionvariesbystate.Forexample,asofApril1,2021,thereareeightstatesonthe2012cycle,23states(plustheDistrictofColumbia)onthe2015cycle,17statesonthe2018cycle,andtwostates(CaliforniaandNewYork)onthemostcurrent2021cycle.Additionally,somestatesmaybeondifferentfirecodeandresidentialcodecyclestofurthercomplicatethings.Finally,keepinmindthattheseonlineresourcesmaynotbeup-to-date.ThebestwaytodeterminethecodesAHJsareenforcinginaspecificlocationistocontactthelocalbuildingorfiredepartment. Viewfullsize Whilethe2015versionsoftheIFCandNFPA1docontainsomerequirementsforenergystoragesystems,theyarefewcomparedtothe2018and2021versions.TheESSrequirementsinthe2018version,whilecertainlymorerestrictivethanthe2015version,arerelativelymodest.Ontheotherhand,the2021codesbuildoutESSrequirementsconsiderably. Alsoofinterest,therewerenospecificESSrequirementsintheIRCbefore2018.IRC2018requirementsspecifythatESSmustbe:ListedandlabeledinaccordancewithUL9540Installedpermanufacturer’sinstructionsNotinstalledwithinahabitablespaceofadwellingunitProtectedfromimpactfromvehicleswithanapprovedbarrierVentilatedifbatterychemistryproducesflammablegasduringnormaloperationNFPA855and2021IFC,IRC,andNFPA1TheESSprojectthatledtothefirsteditionofNFPA855,theStandardfortheInstallationofStationaryEnergyStorageSystems(releasedin2019),originatedfromarequestsubmittedonbehalfoftheCaliforniaEnergyStorageAlliance.ThefirstversionofNFPA855soughttoaddressgapsinregulationidentifiedbyparticipantsinworkshopspresentedbytheU.S.DepartmentofEnergyandtheFireProtectionResearchFoundation.The2021versionsofIFC,IRC,andNFPA1basetheirESSfirecoderequirementsonthisdocument.Chapter15ofNFPA855providesrequirementsforresidentialsystems.ThefollowinglistisnotcomprehensivebuthighlightsimportantNFPA855requirementsforresidentialenergystoragesystems.Inparticular,ESSspacing,unitcapacitylimitations,andmaximumallowablequantities(MAQ)dependingonlocation.ESSmustbelistedandlabeledinaccordancewithUL9540andinstalledperthemanufacturer’sinstructions.Aminimumspacingof3feetisrequiredbetweenESSunitsunless9540Atestingallowsforcloserspacing.ESSlocationrequirementsaredetailedforareasincludinggarages,accessorystructures,utilityclosets,andoutdoors.ESSinstalledoutdoorsmaynotbewithin3-feetofdoorsandwindows.NotethatESSunitsmaynotbeinstalledinlivingareasorbedrooms.ThemaximumenergyratingperESSunitis20kWh.ThemaximumkWhcapacityperlocationisalsospecified—80kWhwhenlocatedingarages,accessorystructures,andoutdoorsand40kWhinutilityclosetsorstoragespaces.Forstoragecapacitiesthatexceedtheselimits,non-residentialrequirementscomeintoplay(NFPA855Chapters4-9).Firedetection,includingsmokeandheatalarms,vehicleimpactprotectionwithapprovedbarriers,andventilationrequirementsforchemistriesthatproduceflammablegasduringnormaloperationareaddressed.ElectricvehiclesusedtotemporarilypoweradwellingmustcomplywithNECrequirements,thevehiclemanufacturer’sinstructions,andarenotallowedformorethan30days. Viewfullsize ItisimportanttonotethattheUL9540AtestmethoddiffersfromtheUL9540listingprocess.UL9540AisreferencedbyNFPA855inthecontextoflarge-scalefiretesting.The2021IRCalsoutilizesUL9540AandallowsforcloserunitspacingiftheESS’sUL9540Atestinghasproventhatcloserspacingissafe.TheESSmanufacturerwillprovidetherequiredunitspacingbasedonthis9540Atestingintheirinstallationinstructions.WhilecurrentlyonlyCaliforniaandNewYorkhaveadoptedthe2021IRCandIFC,otherstatesandcitiesarelikelytostartutilizingthiscodecycleinthecomingyearsmakingtheseenhancedESSfirecoderequirementsapplicableacrossabroadersectionoftheU.S.CodesandstandardsthatregulateandguidesolarandenergystoragesystemscontinuetoevolveandbeadoptedthroughouttheU.S.assystemsscaleandmanufacturersintroducenewproductsandsolutionsintothemarket.Stayingup-to-dateonthemostconsequentialcodesandstandardsforESSnotonlyhelpsensuresystemsafetyandfunctionalitybutisalsogoodforbusiness.Systemsthatareup-to-codeleadtohappiercustomers,satisfiedinspectors,andsmootherinstallations. Readytolearnmoreaboutfirecodesforenergystoragesystems?Registernowfora3-hourin-persontrainingonJanuary12,2022,duringtheIntersolarNorthAmericaConference. NotattendingIntersolarNorthAmerica?Registerhereforaliveorrecordedversionofthe3-hourtraining.AuthorJustineSanchezisthesolar-plus-storagedirectoratMayfieldRenewablesandanNECCode-MakingPanel13member.Tostartasolar-plus-storagedesignprojectorinquireaboutprojectconsulting,simplyfilloutthisquickform.  NewerPostARenewedCollaborationOlderPostTheComingHomeEnergyManagement(R)Evolution