Review on recycling of valuable elements in end-of-life photovoltaic modules

In 2022, the global photovoltaic (PV) industry entered the terawatt (TW) era, with China maintaining its position as the world’s leading PV module producer for 18 consecutive years. Driven by technological upgrades and the end-of-life of early-generation installations, a wave of PV module retirements is imminent in China. These end-of-life modules contain valuable resources—including glass, silicon, aluminum, silver, and copper—with non-ferrous metal grades often exceeding those of primary ores, presenting significant recovery potential. However, they also harbor hazardous elements, such as fluorine and heavy metals. Traditional disposal methods like landfilling and incineration are not only resource-inefficient but also environmentally detrimental. Consequently, PV module recycling has emerged as a critical pathway for achieving green and sustainable development within the PV industry, gaining broad consensus under supportive national policies. This study comprehensively analyzes the current status and retirement trends of the global and Chinese PV industries. It investigates the resource attributes of various retired PV module types, encompassing the weight distribution and economic value of key components, their potential contribution to future solar material demand, and implications for critical mineral supply security. Concurrently, the environmental risk attributes are evaluated. The research further reviews domestic and international policies and regulations governing valuable element recovery, alongside mainstream recycling technologies (physical, chemical, and thermal processes), critically assessing their latest advancements, technical advantages, and persistent challenges. Finally, potential pathways and technological development directions for achieving green, high-value-added recycling of retired PV modules are explored. This work aims to provide theoretical support and novel insights for the efficient resource recovery and circular utilization of PV waste, thereby promoting the development of a closed-loop green supply chain for the photovoltaic industry.