Forecast of photovoltaic material recycling and assessment of supply-demand gaps considering recycling feedback and subsidies

The accelerated expansion of the photovoltaic (PV) industry has led to a widening gap between supply and demand for key raw materials. Accurately assessing the potential of secondary resource supply from retired modules can provide crucial support for recycling system planning and resource management. However, existing forecasting models for photovoltaic waste prediction inadequately account for industrial heterogeneity, policy impacts, and recycling feedback. Moreover, although subsidy policies are regarded as a key driver for unlocking the supply potential of secondary resources, research on the exit pathways for phasing out the subsidies from their introduction to eventual elimination remains insufficient. Based on China's current photovoltaic development landscape, this study constructs a photovoltaic waste prediction model that integrates industrial heterogeneity, policy factors, and recycling feedback, while incorporating a dynamic subsidy mechanism. Research findings indicate that the subsidy policy significantly increased recycling rates (by nearly 6% in the first year) and recycling volumes. The subsidy could cumulatively increase the volume of recycled modules by 1 to 2 million tonnes. Materials such as aluminum and silicon, predominantly found in crystalline silicon modules, can meet a large share of demand (approximately 40%) through secondary supply. A dynamic subsidy mechanism that links subsidy adjustments to recovery rates, coupled with a subsidy period of 5–8 years, represents the optimal solution for balancing costs and benefits. This study provides decision support for optimizing PV circular economy policies and strategic resource management.