summary technical issues associated with pv systemshbelc.org/pdf/standards/photovoltaics.pdf ·...

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6.07.16, PV Position Paper_v12.2.docx 1/5 * 501 (c)(3) nonprofit education organization International Institute for Building-Biology ® & Ecology* www.building-biology.org Photovoltaic Electrical Systems Electromagnetic Exposure Issues & Overview of Configurations Summary Photovoltaic (PV) power generation systems as well as other alternative energy producing systems (e.g. wind generators and gas power, on-site generators) are not recommended for people who are experiencing electromagnetic sensitivity and especially for people displaying the symptoms of Electromagnetic Hyper-Sensitivity (EHS). Asymptomatic people are cautioned to evaluate all the pros and cons before moving ahead, especially as pertains to the generation of unwanted EMF radiations and effectiveness of filtration options offered by various system purveyors for dealing with these unwanted radiations. Technical Issues Associated with PV Systems Alternative energy producing systems create ElectroMagnetic Interference (EMI), popularly termed Dirty Electricity (DE) which is broadcast in the air in the vicinity of the inverter and charge controller (if battery backup is part of the system) and is also carried to the living space by the electrical wiring of the building. With multiple power source systems (e.g. power grid, a PV system, on-site generator), this noise can be amplified by system configuration. Resolution by installing after-market controls is difficult. There are after-market DE filters (known as Resistance-Capacitance Filters) which can diminish this noise. These filters are installed in parallel by plugging them into electrical outlets. However, the efficiency of noise reduction varies depending on PV equipment brand and model and on the electrical system characteristics in the building served by the system. Since EHS symptoms can be frequency specific, what works for one individual may not work for another. Testing of Resistance-Capacitance filters has shown that while these filters do eliminate some DE frequencies, this is accompanied by generation of new DE frequencies. In-Line or Pi filters (also known as Capacitance-Inductance filters) appear to be the most effective filter. However, they are placed in series with the problematic PV source supplying electricity to the house, so they must be able to handle the full amperage of the source. This makes the filter more expensive and requires an electrician for installation. Be aware that add-on filters that were not part of the original equipment are at risk of being removed by PV service personnel who do not understand their function and may be suspicious that they are responsible for the service problem they are trouble-shooting. You will need to be vigilant during service calls to make sure your add-on filters are not disconnected. Filtration of DE is a very technical and complex topic. PV equipment manufacturers’ filters are designed for their specific system and would be the most efficient filtration for the noise that system creates. The two manufacturers we talked to were not filtering for biological benefit, but rather against interference with other electronics. They were totally unaware of the need for advanced DE filtration to protect people. The awareness of these manufacturers is probably representative of the industry as a whole. The complexity of this issue is discussed in the following research paper available at http://www.hbelc.org/pdf/standards/dirty-electricity.pdf

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Page 1: Summary Technical Issues Associated with PV Systemshbelc.org/pdf/standards/photovoltaics.pdf ·  · 2016-06-09Residential Alternative Energy Systems 06.07.16, PV Position Paper_v12.2.docx

6.07.16,PVPositionPaper_v12.2.docx 1/5 *501(c)(3)nonprofiteducationorganization

InternationalInstituteforBuilding-Biology®&Ecology*www.building-biology.org

Photovoltaic Electrical Systems Electromagnetic Exposure Issues & Overview of Configurations

SummaryPhotovoltaic (PV)powergeneration systemsaswell asotheralternativeenergy producing systems (e.g. wind generators and gas power, on-sitegenerators) are not recommended for people who are experiencingelectromagnetic sensitivity and especially for people displaying thesymptoms of Electromagnetic Hyper-Sensitivity (EHS). Asymptomaticpeople are cautioned to evaluate all the pros and cons before movingahead, especially as pertains to the generation of unwanted EMFradiationsandeffectivenessoffiltrationoptionsofferedbyvarioussystempurveyorsfordealingwiththeseunwantedradiations.

TechnicalIssuesAssociatedwithPVSystemsAlternative energy producing systems create ElectroMagnetic Interference (EMI), popularly termed DirtyElectricity(DE)whichisbroadcastintheairinthevicinityoftheinverterandchargecontroller(ifbatterybackupispartofthesystem)andisalsocarriedtothelivingspacebytheelectricalwiringofthebuilding.Withmultiple power source systems (e.g. power grid, a PV system, on-site generator), this noise can beamplifiedbysystemconfiguration.Resolutionbyinstallingafter-marketcontrolsisdifficult.Thereareafter-marketDEfilters(knownasResistance-CapacitanceFilters)whichcandiminishthisnoise.Thesefiltersareinstalledinparallelbypluggingthemintoelectricaloutlets.However,theefficiencyofnoisereductionvariesdependingonPVequipmentbrandandmodelandontheelectricalsystemcharacteristicsinthe building served by the system. Since EHS symptoms can be frequency specific, what works for oneindividualmaynotworkforanother.TestingofResistance-CapacitancefiltershasshownthatwhilethesefiltersdoeliminatesomeDEfrequencies,thisisaccompaniedbygenerationofnewDEfrequencies.In-Line or Pi filters (also known as Capacitance-Inductance filters) appear to be themost effective filter.However,theyareplacedinserieswiththeproblematicPVsourcesupplyingelectricitytothehouse,sotheymustbeabletohandlethefullamperageofthesource.Thismakesthefiltermoreexpensiveandrequiresanelectricianforinstallation.Beawarethatadd-onfiltersthatwerenotpartoftheoriginalequipmentareatriskofbeingremovedbyPVservicepersonnelwhodonotunderstandtheirfunctionandmaybesuspiciousthattheyareresponsiblefortheserviceproblemtheyaretrouble-shooting.Youwillneedtobevigilantduringservicecallstomakesureyouradd-onfiltersarenotdisconnected.FiltrationofDEisaverytechnicalandcomplextopic.PVequipmentmanufacturers’filtersaredesignedfortheir specific systemandwouldbe themost efficient filtration for thenoise that system creates. The twomanufacturers we talked to were not filtering for biological benefit, but rather against interference withotherelectronics.TheyweretotallyunawareoftheneedforadvancedDEfiltrationtoprotectpeople.Theawarenessofthesemanufacturersisprobablyrepresentativeoftheindustryasawhole.Thecomplexityofthis issue is discussed in the following research paper available athttp://www.hbelc.org/pdf/standards/dirty-electricity.pdf

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Residential Alternative Energy Systems

06.07.16,PVPositionPaper_v12.2.docx 2/5 *501(c)(3)nonprofiteducationorganization

MitigationofSolarInverterDirtyElectricitywithIn-linePifilter,MichaelJ.SchwaebePE,BBEC“Abstract:ThispaperreportsthatonebrandofsolarinvertercreatesDEandthatResistance-CapacitancetypefiltersdonotfullymitigatetheDEandcanmakemattersworse.ThisisillustratedbyoscilloscopemeasurementsofelectricalsystempropertiesandambientEMRfromdirtyelectricitywiththesolarsystemrunningandoffalongwithdifferentfilterconfigurations.ThispaperalsoillustratestheeffectivenessoftheDNAlinefiltersinremovingthedirtyelectricitycausedbysolarinverteroperation.”

In addition to DE, another issue that plagues alternate power systems with more than one generator isunwantedgroundingsystemcurrent flowthat is likely togenerateobjectionableACmagnetic fields in thehome.Thepotentialhealtheffectsofpulsingmagneticfieldsareamplifiedinsuchconditions.UnwantedcurrentflowandtheattendantACfieldsarenotcorrectablebyDEfiltration.Groundingproblemsareoftwotypes:

1. Electricalsystemgroundingerrorsinyourhouseorevenneighboringhouses.CurrentontheelectricalgroundingsystemwillcausebroadlydistributedmagneticfieldsthataccentuatetheeffectofDirtyElectricityalreadyonthewiring(i.e.DEfromthePVsystem,personalelectronicequipmentandDEthatentersyourelectricalsystemfromtheutilitysystem).Groundingerrorsaretimeconsumingtomitigate.Groundcurrentsfromneighborsarenotwithinyourcontrol.

2. Multiplegeneratingsourcesinabuildingcomplicategrounding,therefore,groundingerrorsaremorelikely.Forexample,utilityelectricitysourceandoneormorealternativepowersourceslikeaPVsystemand/oragenerator.

Movingforward,itisimportantfortheInstituteforBuildingBiology&Ecologyandpeopleitservestoexpectmore frommanufacturers in termsofDE filtration thantheyarecurrentlydeliveringasstandardproduct.This will be accomplished by consumers asking informed questions about DE generation and theeffectivenessofDEreductionbybuilt-infiltrationmethods.Companieswill design solutions based on customer demand; if no one demands safer products then it isunlikelythatmanufacturerResearch&Developmentwilladdressthisissue.Asforgroundingerrors,thatisintherealmofelectricalcodes.Electricalcodestypicallydealonlywithfireandpersonalshockissues,notDirtyElectricityorobjectionablecurrentflowonthegroundingsystem.SomeelectricianshavebeenintroducedtotheseissuesthroughtheBuildingBiologyInstitute,butunlesselectricalcodesandelectricianeducationarechangedtoreflecttheseproblemsweareinanuphillbattle.ItisvaluabletonotethatPVsystemsdonotrequirea"Smart"Meter.Anystyleofutilitymeter,analogordigital,thatmeasureselectricityusagewillwork.ThePVgrid-tieinverterconnectstothepowerpanelandtheutilitymeterconnectsontheotherside.Asmartmetersemitsburstsofpulsedmicrowaveradiationallthetime.TheWorldHealthorganization(WHO)ruledthistypeofradiationapossiblehumancarcinogen(May31,2011).TheAmericanAcademyofEnvironmentalMedicine,anorganizationrepresentingenvironmentalmedicineMDs,releasedaletteronJan25,2012tothePublicUtilitiesCommissionofCaliforniaspeakingtowirelessradiation.Themostimportantpassageisthis:Chronicexposuretowirelessradiofrequencyradiationisapreventableenvironmentalhazardthatissufficientlywelldocumentedtowarrantimmediatepreventativepublichealthaction.”(https://www.aaemonline.org/emf_rf_position.php)

Page 3: Summary Technical Issues Associated with PV Systemshbelc.org/pdf/standards/photovoltaics.pdf ·  · 2016-06-09Residential Alternative Energy Systems 06.07.16, PV Position Paper_v12.2.docx

Residential Alternative Energy Systems

06.07.16,PVPositionPaper_v12.2.docx 3/5 *501(c)(3)nonprofiteducationorganization

HealthIssuesAssociatedwithDEMorethantenyearsagoitwasestimatedthat3%oftheUSpopulationwaselectrosensitiveandupto35%had symptomsofElectromagneticHyper-Sensitivity (EHS).Today these figuresare surelyhigherwith theeverincreasingproliferationofelectronicdeviceswithpower-switchingnon-linearloadsproducingDE,andthealmostuniversaluseofwirelesstechnologies.IsDEahealthhazard?While researchand case studies todatehavenotbeenextensive, there is growingsufficient evidence that high frequency voltage transients canproducenegativebiological effects. Here issomeofthisevidence:• Cancer–AmericanJournalofIndustrialMedicine,51(8):579-586,2008• Diabetes–Bioelectromagnetics,25(3):160-166,2001;ProceedingsfromtheInternationalConferenceofChildhoodLeukemia,London,September6-10,2004;ElectromagneticBiology&Medicine,25:259-268,2006;ElectromagneticBiology&Medicine,27:135-146,2008

• Neurotransmitterlevels–ElectromagneticBiology&Medicine(online),InformaHealthcare,January18,2013

• Asthma–ArchivesofPediatrics&AdolescentMedicine,165(10):945-950,2011 • MultipleSclerosis–ProceedingsfromtheInternationalConferenceofChildhoodLeukemia,London,September6-10,2004;ElectromagneticBiology&Medicine,25:259-268,2006

• Headaches–ProceedingsfromtheInternationalConferenceofChildhoodLeukemia,London,September6-10,2004

• ImprovedTeacherWell-beingandStudentBehavior–ScienceoftheTotalEnvironment,April21,2008;Proceedingsfromthe3rdInternationalWorkshopontheBiologicalEffectsofElectromagneticFields,Kos,Greece,October4-8,2004

• ChildhoodLeukemia–MedicalHypothesis,56(3):290-295,2001• AttentionDeficitDisorder–JournalofDevelopmentalandBehavioralPediatrics,32(8):634,2011• AmyotrophicLateralSclerosis(ALS)–MedicalHypothesis,74(6):1086-1087,2010• SymptomsofElectromagneticHypersensitivity(EHS)–ProceedingsfromWorldHealthOrganizationWorkshoponElectricalHypersensitivity,Prague,CzechRepublic,October25-26,2004;ScienceoftheTotalEnvironment,November1,2011

TheInternationalInstituteforBuildingBiology&Ecologybelievesthatharmfromelectromagneticradiationdoesnotneedtobeconclusivelyprovenforactiontobetaken.Thismeansthatintheabsenceofscientificconsensus the Precautionary Principle needs to be invoked where scientific investigations have found aplausiblerisk.Itisatthispointthatthepublichealthshouldbeprotectedwithbiologically-basedradiationexposurestandards.RememberthatDEoccursinanintermediaterange(2kHz–100kHz)betweenthelowerpowerfrequencies(calledELF)andthehigherradiofrequencies(calledRF).TheInternationalAgencyforResearchonCancer(IARC)hasclassifiedbothofthese—ELFmagneticfields(2001)andRFmicrowavefields(2011)—asGroup2BPossibleHumanCarcinogens.ItisinterestingthatinitsconclusiontheWorldHealthOrganization(WHO)EnvironmentalHealthCriteria238—ExtremelyLowFrequencyFields(2007)stated:“AcutebiologicaleffectshavebeenestablishedforexposuretoELFelectricandmagneticfieldsinthefreq-uencyrangeupto100kHzthatmayhaveadverseconsequencesonhealth.”

(Thisreportcontainsthecollectiveviewsofaninternationalgroupofexpertsanddoesnotnecessarilyrepresentthedecisions or the stated policy of the International Commission of Non-Ionizing Radiation Protection, theInternationalLabourOrganization,ortheWorldHealthOrganization.)

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Residential Alternative Energy Systems

06.07.16,PVPositionPaper_v12.2.docx 4/5 *501(c)(3)nonprofiteducationorganization

Asmoreresearchisforthcoming,theInternationalInstituteforBuildingBiology&Ecologybelievesitwilladdtoandconfirmwithmorecertitudethatdirtyelectricitypresentsahealthhazard,andgovernmentandindustryshouldtakestepstohelpmitigatethistypeofelectromagneticradiation.TypesofSolarElectricityGenerationSystems1[AlsocalledPhotoVoltaic(PV)Systems] 1.GRID-TIE(BATTERYFREE)The simplest and most cost effective PVdesign formostsites is the "Grid-Tie" (sometimesreferredtoasintertied or utility-interactive) system.Thissystemdoes notprovide backup powerduring apoweroutage(evenifthesunisshining).Poweryougenerateinexcessofyourusageatanymomentisfedback intoyourutility’selectricalgridandoffsets thecostofthepoweryouconsumewhenthePVsystemisnotgenerating. The invertershowninthepicture istheprimarysourceofDE.

2.GRID-TIEWITHBATTERYBACKUPThe Grid-Tie WithBattery Backupsystemalsofeeds back unused electricity producedtotheelectric utility grid as with system #1. But thissystemhastheaddedability tostoreenergy inanon site battery bank for use in the dark hours orfor use during a utility service interruption.Duringaserviceinterruptionthebatteriesprovidepowertoafewselectedorcriticalapplicationslikethe refrigerator, freezer, some lights, phones,alarm system.With thisbenefit comesincreasedcomplexity, cost and maintenancerequirements. The battery charge controllershowninthepictureisanothersourceofDE.

3.STAND-ALONEorOFF-GRIDAbuildingwiththissystemisnotconnectedtotheutilityelectricalgrid.TheOff-GridorStand-AlonePVSystemincorporatesamuchlargeamountofbatterystoragethansystem#2sothereisenoughcapacitytoprovidepowerforacertainnumberofdays(andnights)inarowwhensunisnotavailable.Thearrayofsolarpanelsmustbelargeenoughtopowerallenergyneedsatthesiteandrechargethebatteriesatthesametime.MostOff-GridsystemsalsohavemorethanjustPVgenerationandcouldincludeWindand/orHydropower.Ahydrocarbonpoweredgenerator(naturalgas,propane,gasolineordiesel)isoftenusedforemergencybackuppowerandtorechargethebatterieswhenneeded.

1AllimagescourtesyofAladdinSolar,LLCservingareasofMinnesota

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Residential Alternative Energy Systems

06.07.16,PVPositionPaper_v12.2.docx 5/5 *501(c)(3)nonprofiteducationorganization

TypesofInvertersUsedinPhotovoltaicSystemsThetypeofinverterisdeterminedbythegenerationobjectivesofthePVsystem.Inverterscanbedividedintothreebroadtypeslistedbelow.Invertersaretypicallyasingleboxcontainingtherequiredcomponentstomeettheobjectiveandlocatednearthemainelectricalpanelinhomeoralternativelynearthesolarpanelstypicallyontheroofinmosthomeinstallations.StandAloneInverterThisinverterisusedinisolatedsystems(notconnectedtotheutilitygrid)wheretheinverterdrawsDCenergyfrombatterieschargedbyphotovoltaicarrays.Manystand-aloneinvertersalsoincorporateintegralbatterychargerstoreplenishthebatteryfromanACsourcesuchasafossilfuelpoweredgenerator.Grid-tieInverterThisisthemostprevalentPVsystemonresidentialhomes.Thisinverterisspecificallydesignedtomatchphaseandfrequencywithutility-suppliedgridpower.Additionally,grid-tieinvertersaredesignedtoshutdownautomaticallyuponlossofutilitysupplyprimarilyforreasonsofsafetyforutilityworkers.ThisPVsystemwillnotprovidebackuppowerduringutilityoutages.InverterLocationTraditionally,theinvertershasbeenlocatedatonepointinthesystem,usuallynearthecircuitbreakerpanel.Amorerecentdevelopmentisthemicro-inverterwhichislocatedbeloweachsolarpanel.LowvoltageDCfromthepanelgoesintothemicro-inverterandisconvertedto120/240voltAC.Thisarrangementreducethemagnitudeofcurrenttobetransmittedandallowsthepanelstobefurtherawayfromthehouse.The120/240voltsisthensenttothecircuitbreakerpanelwhereitistiedintotheutilitygrid.Ofinterestwiththerooflocatedmicro-inverterapproachistheabilitytoavoidhavingasinglepointinverterinalocationthatexposessomeareaofthehousetotheunwantedradiationsemanatingfromtheinverter.However,newersolarpanelsproducehighervoltage,sothePVpanelscannowbelocatedawayfromthehousewithoutusingmicro-inverters.BecauseofthisPVpanelscanbegroundmountedawayfromthebuildingwherethereisthebestsunexposureindependentofbuildinglocation.WiththeabilitytohaveremotelocationofthePVPanels,alltheelectronics(includingtheinverter)canbemovedawayfromthehousetolessontheinherentEMFs.Additionally,intheeventofahousefire,roofmountedPVpanelsareashockhazardandmaypreventthefiremenfromchoppingholesintheroof.WithPVpanelsontheroofthefiremenmayletthehouseburnuntiltherooffallsinthenpourwaterthroughtheroofhole.BatteryBackupSystemsNeedAnotherInverterThisinverterisdesignedtodrawenergyfromabankofon-siteelectricitystoragebatteries,converttheDCtoACwhichisexactlymatchedtothephaseandfrequencyoftheutilitygridsothatexcessenergycanbeexportedtotheutilitygrid.TheseinverterproducetheirownDE.ThisisinadditiontoDEproducedbytheinvertersusedtoconvertthesolarpanelDCtoAC.–––––––––––Reportresearched,writtenandreviewedby:LawrenceGust,EE,BBEC,MichaelSchwaebePE,BBEC,SparkBurmasterEE,BBEC,SoniaHoglanderEE,BBEC,ChristopherBell,BBEC,JeanneMcLaughlin,BBEC."