SolarPanels

“New”ChallengefortheFireService

InternationalFireSafetyAssociation's"FirefightersSafety"VatrogasniCommunityofPrimorsko-goranskaCounty,Rijeka.

ShanRaffelAFSMEngTechCFIFireEChurchillFellow

Objectives• Backgroundongrowthofsolarenergy

• KeydifferencesbetweenACandDCcurrents

• OverviewofcommonPVsystems

• Thehazards

• Theneedforawarenessandeducation

• Optionsfordealingwiththehazard

• Thechallengeoffuturedevelopments(BatteryStorage)

The Growth of Solar Energy

The Growth of Solar Energy

• GlobalpressuretoreducecarbonemissionstomeettheParisClimateAgreementTargets

The Growth of Solar Energy

• GlobalpressuretoreducecarbonemissionstomeettheParisClimateAgreementTargets

• Incentivesandsubsidieshelptoincreasedemand

The Growth of Solar Energy

• GlobalpressuretoreducecarbonemissionstomeettheParisClimateAgreementTargets

• Incentivesandsubsidieshelptoincreasedemand• Costofinstallationdropsduetomassproductionandinnovation

The Growth of Solar Energy

The Growth of Solar Energy• Newinstallationsin2015were50GW

The Growth of Solar Energy• Newinstallationsin2015were50GW• Newinstallationsin2016were76GW(50%in1year)

The Growth of Solar Energy• Newinstallationsin2015were50GW• Newinstallationsin2016were76GW(50%in1year)• Globalcapacity:• 2000insignificant• 201050GW

• 2016305GW

Projected to triple by 2020

Key Differences Between AC and DC

Question:

WheredidAC/DCoriginate?

Australia!

Australia!

Australia!

Nikola Tesla

Tesla vs Edison• ACElectronflowvibratesbackwardsandforwards,at50to60cyclesper

second(Hertz)

• Contactwithaconductorwillcausepowerfulmusclecontraction

• 50to60zeropointswhichcouldallowyoutopotentiallydisconnect

• Easyandinexpensivetoincreaseordecreasevoltagethrougha“Transformer”

• HighVoltageandLowCurrentisveryefficientwaytotransferelectricalenergyoverlongdistances

• LessArcingonswitching

Direct Current - DC• Unidirectionalflowofelectronsfromthe+vetothe–veterminals

• Mechanical

• Dynamo

• Alternatorthrougharectifierorcommutator

• Chemical(Batteries)

• PVSolarPanels

• KEYPOINT–ithasnofrequency!=YOUCANNOTLETGO!

Solar Cell• PV=PhotoVoltaic=LightElectricity• IndividualCells=0.6Vdc

Solar Panel• Cellsconnectedinseries=SolarPanelrangingfrom1Wto315W• Typically45–50Vols• 250W

PV Array - Strings• PanelsconnectedinseriestoformaString• Oftenmorethanonestringconnectedinparallel

3 Most Common Solar (PV) Systems

• Gridinteractive–mostcommonlyseenondomestichomes,factoriesandmostSolarFarms.

• OffGridSystems–locatedtraditionallyinremoteareas

• GridConnectedBatterybackup–akaHybridSystem

Grid Interactive

Off Grid System

Hybrid /Grid storage systems

Lithium-ion battery storage system

Powerwall2wall-mounted,14kWhlithium-ionbatterystoragesystem

The Hazards• Installationsmaynotbeeasilyidentifiableandmaybehidden(flatroof)

• Restrictedaccesstoisolationswitches

• PVarrayswhichstandofffromtheroofmaycauseachannellingeffect

• AdditionalloadonfireaffectedroofstructuresfromweightofthePVarray,and/oradditionalwind-loading

• Poorlyinstalledsystemsmayobstructorrestrictuseofroofwindowsasmeansofescapeorhinderfirefightingoperations.

FireandSolarPVSystems–RecommendationsfortheFireandRescueServices,,ScienceandInnovation,BEIS,15thMay2017

The Hazards• GlassfromthePVmodules,maybreakandfallontopersonnelbelow

• GeneralelectricshockriskfromPVsystemsandtheproductionofpotentiallyveryhighvoltageDCelectricity

• PartsofthesystemarealwayslivewhilethePVmodulesareexposedtolightenergy

• RiskofelectricshockifcablesarecutorbecomedamagedbyfireFireandSolarPVSystems–RecommendationsfortheFireandRescueServices,,ScienceandInnovation,BEIS,15thMay2017

Reasons for failure for PV Systems• Underreported–Limiteddata

Reasons for failure for PV Systems

•DCIsolators•DCConnectors• Inverters•DCCables•PVModules

Reasons for failure for PV Systems

•36%Poorinstallation•12%Faultyproducts•5%SystemDesignerrors•50%undetermined

The DC Danger Zone

• IsolationoftheInverterstillleavesthepanelsandwiringlive• Metalroofing,guttersorotherstructuralelementsmaybecomelive• Highpotentialforelectricshock,severearcingandburns

• PanelsexposedtolightwillcontinuetogenerateDCpower

The DC Danger Zone Thresholds

• Safe=<2mA(milliamps)• Perception=<40mA• 40mA=Lock-on• 240mA=ventricularfibrillation• Over240mA………..itjustgetsworse!

Potential Exposure to the DC Danger Zone• FiresoriginatingfromPVSystems

• Exposureduringroutinefire/rescuein

damagedstructures

• Hail/storm/flood

Research - UL

1.Impactofartificiallightsources2.ExtinguishingMedia3.Optionsforde-energising

• ULFIREFIGHTERSAFETYRESEARCHINSTITUTE• https://ulfirefightersafety.org/• http://di0zyw94wnben.cloudfront.net/lsver08092017343257432/courses/170/631320/PVandFirefighterSafety/player.html

Artificial Light

Impact of Light from Fire

Extinguishing Media - UL• Water

• ClassA

• SaltWater

Water, Class A - UL• Littledifferencebetween“pondwater”andClassA

• Evenaslightlyopenedpattern(10degrees)significantly

reducedleakagecurrent

• At1000Vdcaminimumdistanceof20‘(6m)isrequiredto

reducetheshockhazardtobelowthe2mAsafetythreshold

Salt Water - UL• SaltWateris50Xmoreconductive

• Don’teventhinkaboutit(myinterpretation)

De-energising with Tarps - UL • Heavy,denselywovenfabricanddarkplasticfilmsreducethe

powerfromPVtonearzero

• iflightcanbeseenthroughatarp,itshouldNOTbeused

• Awettarpmaybecomeenergizedandconducthazardous

currentifitcontactsliveequipment.

• FirefightingfoamshouldNOTbereliedupontoblocklight.

De-energising - UL Tarps• Difficultiesinplacement

Structuraldamagetotherooforpanels

Pitch/limitedspace

Wettarpscanbecomeconductive

Risk Assessment• Extentofdamagetoroofstructure

• Roofingconstructionandmaterial(metal/concrete/tile/

etc)

• Systemsize,configuration,andcondition

• UtiliseDronesorAerialappliances

• Avoiddirectcontactofladdersongutteringorroof

Risk Assessment

Our Experience• IssueswithMetalroofingorguttering

• Theroofisoftenfiredamagedandnotsafetoplacecrewson

• CannotplaceatarponanarcingorburningPVcomponents

Recent Innovations

• Non-flammablerapiddryingliquidthatblocksthelight

• Canbeappliedfromadistance

• Peelsoffeasily

TUV research

• 0%/40%/100%comparisons

TUV research

Mission Critical Summary• ThereisaKNOWLEDGEGAP–Rapidchangesintechnology

• Educatefirefightersofthehazards

• DevelopTacticalSOP’srelevanttoyourcontext/riskprofile

• Investintoolsthatwill

• Keepingfirefighterssafe

• Keepthepublicsafe

• Minimisepropertyloss

• Providepracticaltraining

The Next “New Challenge”• HybridBatteryStorageSystems

• Enormousenergyinsideyourhouse

• Electriccars

The Next “New Challenge”“Theproblemisthatburninglithium-ionbatteriesemitslargeamountsoftheverytoxicsubstancehydrogenfluoride(hydrofluoricacid)whenitburnsorvents.

Hydrogenfluorideistoxicbothbypenetrationthroughtheskinandinhaling.Itrequiresaspecialantidoteforthe

affectedpersonandwateraloneisnotenoughfordecontamination.TestsshowthatregularfirePPEturnoutgeararenotresistanttohydrogenfluorideformorethan

aminute.“UtkikenFireandRescueIntelligenceOctober11,2017

Author:PerOlaMalmquist.FireProtectionEngineer,FireandRescueIntelligenceEngineer,FormerBattalionChiefFromSweden

Stay Safe. Stay Informed

• Hvalati

• Živjeli☺

ResourcesUL:https://ulfirefightersafety.org/resources.html#traininghttps://www.ul.com/global/documents/offerings/industries/buildingmaterials/fireservice/PV-FF_SafetyFinalReport.pdfBRE:https://www.gov.uk/government/publications/fire-incidents-involving-solar-panelsPVStop:http://www.pvstop.com.au/products/ Other:www.ata.org.au/wp-content/projects/FireRisksOfSolarPV_ATA_D16_Final.pdf

www.nfpa.org/~/media/files/news-and-research/.../photovoltaicbrooks.pdf?la=enhttps://www.utkiken.net/http://www.irecusa.org/http://www.iaff.org/pvsafetytraining/