Overview of global status and challenges for end-of-life crystalline silicon photovoltaic panels: A focus on environmental impacts.

Recent developments in photovoltaic (PV) technology have enabled a reduction of fossil fuel usage and subsequent carbon dioxide (CO) release from energy production. However, end-of-life (EoL) crystalline silicon (c-Si) PV panels have become an emerging waste issue. This overview attempts to update and forecast the global status of renewable energy capacity and c-Si PV waste generation under different scenarios and to present a summary of the recent literature on recycling technologies and life cycle assessment (LCA) of EoL c-Si PV panels with a focus on reclaimable resources. For most LCA studies in the 1980s and the 2000s, the EoL phase of PV systems has often neglected or oversimplified (e.g., disposal after low-rate recovery) the fact that various recycling procedures and reclaimable resources from each stage cannot be appropriately considered. A limited number of studies have been available since the 2010s that highlight the high-rate recovery from EoL PV panels. However, the differences in functional unit, system boundary and impact analysis methodology make it difficult to compare the results directly, and spatio-temporal uncertainties are yet to be thoroughly quantified due to the lack of workable localized data. More efforts are needed to identify complementary environmental impacts (i.e., burden and credit) from the individual recycling processes. Correspondingly impacts from transport need to be fully incorporated for the optimization of the recycling process which has been neglected in most of the previous studies.