Technologies for resource-efficient recycling of end-of-life crystalline silicon photovoltaic panels

Abstract

Global PV installations recently crossed the terawatt scale. The growth of photovoltaic (PV) installations is an important and desirable element in generating clean electricity and combating climate change. However, with increased use of PV panels for energy production enormous volumes of PV waste would be generated that would need to be dealt with in an environmentally responsible manner. In this work we present early-stage research results based on experiments conducted with recycling end-of-life (EOL) crystalline silicon (c-Si) PV panels promoting resource efficiency and circularity. We explore experimental pathways for both close-loop and open-loop recycling of EOL PV panels. For closed-loop recycling we present experimental results using the recently developed electrohydraulic shock wave-based fragmentation (EHF) of PV panels. The EHF process allows for the recovery of almost all valuable materials used in the manufacturing of PV panels. We further provide a succinct literature review for further downstream treatment of the end products obtained after EHF processing of EOL PV panels to recover precious metals such as Silver. For open-loop recycling, we propose using the panels in the production of ferrosilicon compounds, thereby reducing the emissions of greenhouse gases accompanied with their production. Through experiments it was onbserved that the size of the recycled Si does not impact the microstructure of the FeSi produced, which means that the technology could be easily used to handle different sizes of Si source. Through careful experiments and analysis we provide recycling methods to improve the circularity and resource efficiency in the management of end-of-life c-Si PV panels. Both experimental recycling pathways discussed in this work could potentially provide sustainable technical pathways to recycle EOL PV modules, which does not involve producing harmful greenhouse gases.