Evolutionary impacts of policy instruments on photovoltaic module recycling: A systemic evaluation of long-term dynamics

The solar photovoltaic (PV) industry is entering the stage of concentrated component retirement. Policy is important to ensure sustainable development at this initial stage. However, its potential impact on the implementation of PV recycling in China remains unclear. In this study, a system dynamics model involving different stakeholders was constructed to simulate and explore the effects of several policy tools, including the deposit-return system, mandatory recycling policy, recycling subsidies, tax incentives, and carbon trading policy, on changes in the volume and rate of recycling of retired PV modules, profits of PV manufacturers and recyclers, and reductions in carbon emissions under different policy scenarios. The results indicated that under the baseline scenario, the cumulative PV installation in China will reach 3882-4745 gigawatt (GW) by 2035, involving a reduction of 21.1-26.8 million tons (Mt) of carbon emissions while generating 52-64 GW of waste. All policies, apart from the deposit-return system, performed better than the baseline policy to varying degrees in single-policy implementation scenarios, with the carbon trading policy having the most significant impact on enhancing the end-of-life PV module recovery rate. Under combined policies scenario, different combinations were associated with varying outcomes, with the combination of the carbon-trading and mandatory recycling policies being the most effective in promoting PV recycling. However, the integration of deposit-return policies with other policies resulted in relatively weaker policy effects. In summary, policy tools should be designed and applied flexibly in terms of their specific effects, thereby driving the sustainable development of the PV recycling industry in China.