Aluminum saving and CO₂ emission reduction from waste recycling of China's rooftop photovoltaics under carbon neutrality strategy

Rooftop photovoltaics (RPVs) are crucial for decarbonizing the power sector and achieving carbon neutrality, with expected future capacity increases. The growth of RPVs necessitates substantial aluminum (Al) resources, contributing significantly to carbon dioxide (CO₂) emissions from Al production. Given China's bauxite shortage, recycling Al from waste RPV panels presents an effective solution to enhance resource security and mitigate CO₂ emissions. We developed a framework to project waste RPV quantities and assess the recycling potential of Al and its impact on CO₂ emissions from 2020 to 2060. Our findings indicate potential waste flows of 95–221 million tonnes (Mt) and recycled Al ranging from 5 to 28 Mt, with a primary Al supply gap of 25–43 Mt. Recycling could reduce CO₂ emissions by 35–207 Mt over the period. This research underscores the importance of Al resource security and sustainable RPV industry development in China's pursuit of carbon neutrality.