A comparative life cycle assessment of end-of-life treatment pathways for photovoltaic backsheets

In light of growing photovoltaic (PV) installation capacities around the world, and with it the increasing number of decommissioned modules, it is vital that PV waste is duly treated to recover valuable materials as well as to comply with legislative requirements. The European Union (EU) directive on Waste Electrical and Electronic Equipment and the Restriction of Hazardous Substances mandates manufacturers, retailers, and importers to collectively organise and finance the end-of-life (EoL) stage of electronic products in the EU. Using life cycle assessment, this study makes a comparative analysis of the environmental impacts stemming from the EoL treatment of fluorine-free and fluorinated backsheet material present in PV modules. The 2 potential EoL treatment scenarios explored in this study are incineration and pyrolysis. In general, the life cycle assessment of fluorine-free backsheet material shows better environmental performance than fluorinated backsheet material for both EoL scenarios. For incineration scenario, the environmental impact of fluorine-free backsheet is evidently better than fluorinated backsheet across 11 out of 12 investigated impact categories. Similarly for pyrolysis scenario, fluorine-free backsheets have better environmental performance than fluorinated backsheets in 8 out of 12 impact categories. Furthermore, because of the release of high amounts of hydrogen fluoride, as well as the presence of halogenated hydrocarbons and halogenated aromatics in pyrolysis products, it can be concluded that pyrolysis is not an environmentally feasible pathway for fluorinated backsheet.