Assessment of the environmental impacts and carbon mitigation benefits of photovoltaic systems in China from the life cycle perspective

Photovoltaic (PV) power generation is a key technology to achieve carbon neutrality, and accurate assessments of its sustainability contribute to targeted renewables management. Considering regional differences in PV system structures and the carbon emission intensity of existing electricity sources, this study assesses life-cycle environmental impacts for various PV systems. It also measures the carbon mitigation benefits of PV systems across 30 Chinese provinces and analyzes future trends in their mitigation potential. Findings reveal that marine aquatic ecotoxicity (MAET) is the most prominent environmental impact category for PV systems; silicon-based module rooftop mounted PV system (S-R) exhibits the highest environmental impacts compared to others; and the module production has the highest emissions throughout the life cycle. By comparing the carbon emissions and reductions, the carbon mitigation potential of PV systems in each province varies from 6668.0 to 36836.1 kg/kW. In terms of socio-economic development, the environmental benefits are usually more significant in regions with higher economic levels. The projections indicate that carbon mitigation potentials in almost all provinces are decreasing from 2023–2047, with Ningxia and Hunan maintaining the highest and lowest rankings, respectively. This study could offer critical insights for the targeted development of PV systems in different regions of China.