Comprehensive recycling of silicon photovoltaic modules incorporating organic solvent delamination – technical, environmental and economic analyses

Abstract

Photovoltaic (PV) panel manufacturing is increasing worldwide, which subsequently increases the amount of waste PV. This study proposes to recycle waste PV using organic solvent delamination followed by downstream thermal and leaching procedures. Firstly, experimental data is obtained using small commercial modules by replicating a recycling route taken from the literature. Based on the experimental results, life cycle cost analysis (LCCA) and life cycle assessment (LCA) are applied to evaluate the experimental and optimized industry scale processes. Results show that the main profitable recycling avenues are for aluminum frame and junction box removal; and that downstream processes can separate and recover all the remaining materials, but not profitably. The laboratory and high-throughput-optimized processes, considering the median costs and revenues, have a net cost of 29.00 and 3.30 USD per module, respectively. The complete recovery of materials using the proposed method is unlikely to be profitable and this may only be achievable where labor is not expensive. Alternatively, the complete recycling of waste PV could be made economically viable by reducing process time, increasing automation and/or providing financial subsidies. The environmental analysis, however, shows that the optimized process modelled here has a positive net environmental impact. The results are also compared against the cost/environmental impact of landfilling such waste. In summary, the proposed recycling route is capable of completely recovering the main materials in waste PV (aluminum frames, junction box, silver, copper tabbing, silicon, backsheet and unbroken glass) and can have a positive environmental impact, but it is not economically profitable.