Environmental influence assessment of China’s multi-crystalline silicon (multi-Si) photovoltaic modules considering recycling process

The environmental burden of multi-Si PV modules in China has been discussed in existing studies, however, their data are mostly from local enterprises, and none of their environmental assessment involves the decommissioning and recycling process. This study quantitatively assesses the life-cycle environmental impacts of Chinese Multi-crystalline Photovoltaic Systems involving the recycling process. The LCA software GaBi is applied to establish the LCA model and to perform the calculation, and ReCiPe method is chosen to quantify the environmental impacts. LCA of production process reveals that Polysilicon production, Cell processing and Modules assembling have relatively higher environmental impact than processes of Industrial silicon smelting and Ingot casting and Wafer slicing. Among the 14 environmental impact categories evaluated by ReCiPe methodology, the most prominent environment impacts are found as Climate Change and Human Toxicity. LCA including recycling process reveals that although recycling process has environmental impact, the recycling scenario has less environmental impact by comparing with the landfill scenario. Among the five manufacturing processes and recycling process, environmental impacts of polysilicon production, cell processing and modules assembling have relatively higher uncertainty, probably because that the environmental impact of these processes is high, and standard error of parameters such as electricity, aluminum and glass in the three processes are high. Findings of our study indicate that proper measures should be taken in the high pollution processes such as polysilicon production and cell processing. In addition, efforts should also be made to enhance the recovery rate and seek for more environmental friendly materials in the recycling process.