Post on 06-Aug-2020
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/