Net benefits change of waste photovoltaic recycling in China: Projection of waste based on multiple factors

Abstract

Previous studies on photovoltaic (PV) waste recycling in China have focused on predicting waste volumes and the technical and economic feasibilities of recycling. However, those studies lack an assessment of balance of system (BOS) waste in a PV system and a macro-level assessment of the variation in the net benefits of waste recovery. This paper establishes a multi-factor gray neural network model, combined with the Weibull distribution model, to predict the total PV waste, including modules and BOS. By considering the learning curve of recycling technology and the future projected share of three mainstream technologies (mechanical, chemical, and thermal treatment), we also analyze the changes in net PV recycling benefits across the industry. The results show that total cumulative PV waste is expected to reach about 100 million tons by 2050; of this, 56.13% may be PV modules and 43.87% may be BOS. Three metals, Fe (26%), Al (21%), and Cu (4%), are expected to account for the largest proportion of total metals. Compared with direct landfill disposal, by 2050, the recycling of PV waste could potentially reduce carbon dioxide (CO2) emissions by 1.1E+11 kg, save 1.1E+12 kg of industrial water, and generate 3.6E+11 MJ for primary energy use. The change in net benefits indicates that the benefit could start to generate a positive return by 2026 and total net benefits are expected to reach 90 billion CNY by 2050.