Methodological approaches for resource recovery from end-of-life panels of different generations of photovoltaic technologies – A review

The rise in prominence of solar energy as a green technology demanded economical and sustainable waste management due to the anticipated surge of end-of-life panel waste streams. While there are many advantages to the increase in solar power output, end-of-life solar panels could become a source of hazardous waste. Therefore, the disposal of photovoltaic panels will become a major environmental concern in the next decades. Generations of photovoltaic technologies, namely crystalline silicon, thin-film, and third-generation solar panels, share the goal of achieving waste reduction through useful strategies for recovery of secondary raw materials from obsolete panels. This research reviews the current status and future prospects for valuable constituents, waste projections, and trends in technological advances for recycling and recovery of resource materials from different generations of photovoltaic solar systems. Projections of global photovoltaic waste driven by the expansion of solar system installations illuminate the influx of waste streams that burden the environment if there are no measures in place for sustainable waste management. The crystalline silicon and thin-film PV technologies have demonstrated sufficient advancements in resource recovery technologies for industrial use in circular economy and closed-loop recycling to minimize environmental impacts and prevent leaching of toxic elements. Industrial application of pyrolysis and chemical etching has emerged as a promising approach to recovery of high-purity secondary valuable materials from obsolete c-Si panels. Substantial recoveries of critical from obsolete thin-film panels are notable with the application of mechanical and hydrometallurgical waste treatment techniques. Third-generation waste treatment methods are largely based on laboratory experiments because these solar systems are on the verge of commercialization.