Life cycle assessment of three typical solar energy utilization systems in different regions of China

In the future, solar energy has a major impact on the transformation of energy supply, becoming an attractive option among renewable energy sources. This study compares three typical systems that use solar energy, namely solar water heater (SWH) systems, solar photovoltaic (PV) systems, and photovoltaic/thermal (PVT) systems, under comparable conditions in different regions of China. The comparison is based on a life cycle assessment (LCA), taking into consideration the climate characteristics and energy supply in different regions. The corresponding environmental impact assessment results were obtained using the endpoint method and sensitivity analysis was performed to identify the factors that had a greater impact on the results. The findings indicate that SWH systems are more suitable for the southwest of China, where the power grid structure is dominated by hydropower. PV systems are recommended for northern and northeastern China, where coal power is the main source. In other parts of China, both PVT and PV systems are good options. Taking Shanghai as an example, applying PVT systems in Shanghai can reduce carbon emissions by 11.0% and 55.9% respectively, as well as decrease the environmental impact by 11.1% and 38.9% throughout whole life cycle, compared to PV systems and SWH.