Current status and challenges in silver recovery from End-of-Life crystalline silicon solar photovoltaic panels

The significant expansion of the solar energy industry over the past few decades has led to the deployment of large number of solar photovoltaic (PV) panels. As these panels approach their end of life (EoL), the cumulative waste is expected to grow exponentially. PV recycling has thus become an appealing prospect and many research studies have been carried out to reclaim valuable materials from waste solar panels. Despite these efforts, the recovery of silver (Ag), a crucial and valuable element in the PV modules, is often overlooked, due to its low concentration. Nonetheless, it is a fast depleting resource with limited natural ore deposits. The aim of this review is to present various methods developed for extracting Ag from EoL solar modules. We have compared various approaches used for Ag recovery from EoL solar panels in terms of their environmental and economic impact. Our evaluation indicates that it is impractical to consider Ag recovery procedure in isolation since it would affect module recycling as a whole. Optimising the complete module recycling operation with appropriate Ag recovery process will provide the necessary economic incentive and promote circular economy.