PVRe2 Project Presentation Backsheet Repair and sustainable PV

Sustainablephotovoltaics-PV Re² Yuliya Voronko , Gabriele C. Eder , OFI, Austrian Research Institute for Chemistry and Technology Christian Breitwieser, RembrandtinLack GmbH Nfg. KG Wolfgang Mühleisen, Lukas Neumaier, SAL, Silicon Labs Austria Sonja Feldbacher, Gernot Oreski, PCCL, Polymer Competence Center Leoben Markus Feichtner,KiotoPhotovoltaics Norbert Lenck, VDE Renewables REPAIR OF DEFECTIVE BACKSHEETS Vision of PVRe² Repair of PV defective modules to increase active lifespan of PV modules Improved Recycling strategies Photovoltaics World Magazine 1, 5, 2009 Approach Failure analysis Identification of suitable materials & aplication solutions Repair process (with/without dismounting) §Analyse material compatibility and adhesion of the repair solution with the weathered backshet surface §Identification and optimization of necesary cleaning and pre-treatment steps §Applicability of the repair material in the field §Optimize penetration of the repair coating/adhesive into the cracks §Check sustainability of the repair process (idealy no hazardous or toxic materials) §Investigate long-term stability / reliability of the repaired modules AIM: Repair solution to fil / seal the cracks and restore the (i) protective and (i) electrical insulation function of the backsheet Crackingofco-extrudedPA basedbacksheets §CrackingofPA backsheetsafter 5-8 yearsin operation §Nocrackingduringacceleratingindoor testing Lo n g i t u d i n a l Mi c r o Sq u a r e d G. Eder, Y. Voronko, G. Oreski, W. Mühleisen, M. Knausz, A. Omazic, A. Rainer, C. Hirschl, H. Sonleitner (2019) „Eror analysisofagedmoduleswithcracked polyamidebacksheets“, Solar Energy Materials and Solar Cels 203, https:/doi.org/10.1016/j.solmat.2019.10194 FailureAnalysis Cracksbetwencells üCrackthroughwholebacksheet–Starting fromInnerlayerofbacksheet üStrongmaterialdegradationatEVA interface Cracksalongbusbars üCrackinitiationonmodulebackside Microcracks üWholebacksheetshowscracks Repairable Repairable Not repairable Material selection Re01 Re02 Re03 Re04 Re05 Re06 Re07 Re08 Re09 Re10 Re1 Re12 Re13 Type coatingcoatingcoatingcoatingcoatingcoatingcoatingcoating coating tape tape tape tape Material- type epoxy PUPUacrylatesiliconepoxy epoxy nitrile ruber liquid ruber PU+ acrylate PVC + acrylate TPT + adhesive EVA + PET solvent yes yes Yes nonononoyes yes nononono curing air- drying air- drying air- drying UV, RT air- curing air- curing air- curing air- drying air- drying RTRTRT150°C Repairofbacksheets -multi-stepproces: 1.Cleaning:Wipe with a wet sponge or cloth 2.Pretreatmentofsurface:Primer is only recomended for ruber spray film 3.Fillingofcracks: Low-viscositycoating 4.Barrierlayer(= Weather-resistantcoating): Sealing with a medium-viscosity coating Tape Coating labfieldlabfield local x x x x continuous deck - - x x §Total layer thicknes of the coatings betwen 30 and 50 µm §Application time around 10min per module Characterizationresults Re01 Re02 Re03 Re04 Re05 Re06 Re07 Re08 Re09 Re10 Re1 Re12 Re13 Color trans- parent trans- parent trans- parent trans- parent trans- parent trans- parent black brown black or white trans- parent whitewhitewhite Tapepeel test ü ü ü ü ü ü ü ü ü ü ü - - Scratchtest ü ü ü Chipp- ing ü ü Chipp- ing ü ü ü ü - - Outdor* weathering Yellow- ing ü ü - ü Yellow- ing - Darken- ing ü ü ü - - Crackfiling/ sealing ü ü ü - ü - - ü ü - - - - Film thicknes [µm] 18-2112-1616-61- 30-50- - 3042-100 300+6 0 85+55+300 300+ 300 Favoriteforcontinuousdeck:Re01,Re03,Re05&Re09 üCrackfiling&sealingsucesful üWeatheringstability:nochangeslikedelamination,blistering ormaterialdetachment üEasyhandling Favoriteforlocaldeck:Re10,Re11&Re12: üwiththesematerialscrackfilingisnotposible,butlocal protection/sealingformechanicaldefectscanbeobtained Repair test -intermediate evaluation Code Material Material consumption perModul (1,5 m²) Costs[€] per Modul (1,5 m²) Total costs Dilution 60 g 0,35 € 1,21 € Re 01 Epoxy1-K 72 g 0,86 € Re03 Dilution 66 g 0,38€ 2,34 € PU 2-K 74 g 1,96 € Re 05 Silicon 47 g 8,9 € 8,9 € Re 09 Liquid ruber 100 g1,84 € 4,42 € Primer 60 g 2,58 € Calculated costs depend to material consumption (no wholesale prices) Non-destructivecharacterisationofrepaired modulesin thefieldand in thelab (after coating) vVisual inspection üCoating is intact üNo delamination, bubles or material detachment vTape-peeltest ücoating adheres wel to the surface vSTC Power and EL ünochangesin elctricalpower after coating-proces vColour Change üReference measurementtofolow colourchange withincreasingweatheringtime Outlok vField: Repaired modules wil be monitored in the field (outdor weathering) for 1 year vLab: Repaired modules undergo acelerated reliability testing (DH –TC –DML) §A part of the PV instalations are geting a bit long in the tooth but they most of them are too good to throw away. §However not only older instalation but also medium or likely new plants often show malfunctions. §Gradual power reduction are often only detected after several years. §Others lead imediately to a complete power loss e. g. in the case of earth fault. §In the worst case the electrical safety is no longer guaranted. Motivation 1/5/21 © VDE Renewables GmbH 9 §If you lok in the internet under the search term “Module Repair” you can find a lot of companies and workshops which provide diferent repair options. §According the typical statements, the systems should work after the repair nearly like original conditions. §But it is hard to find a statement how the repaired modules are tested to fulfil the “low voltage directive” which is necessary to declare the CE conformity. §This could be shown if the relevant electrical tests according IEC 61730 are passed. Sustainable PV Modules 1/5/21 © VDE Renewables GmbH 10 §Logistic and handling of the dismantling procedure as wel the transport (without aditional damage) to the “Reuse” partner. §Incoming procedure and control: •Cleaning •Optical Inspection •Electrical inspection (safety and power) §Spliting in groups: •Direct reuse •Repair •Recycling Already running activities 1/5/21 © VDE Renewables GmbH 11 §Legal basis for reuse / reseling? §Which kinds of repair are possible? §Which tests are necessary? §Can the modules be used with the existing certificates? §Which labeling? §… §My idea for the TG 15 is to develop a proposal for a Guideline / TS / Standard to present it later to the IEC WG 2 comission Important open point (only a few, without any claim to completenes) 1/5/21 © VDE Renewables GmbH 12