Assessment of future solar energy potential changes under the shared socio-economic pathways scenario 2-4.5 with WRF-chem: The roles of meteorology and emission

The 26th United Nations Climate Change Conference (COP26) proposes to limit global warming to <1.5 degrees C above pre-industrial levels until 2030 and aligns CO2 emissions with net-zero by 2050. To achieve this goal, it is crucial to replace fossil fuels with renewable and clean energy sources. Among the various renewable energy sources, solar energy undoubtedly stands out as an attractive option. Future meteorological conditions and emission reductions are expected to impact on solar energy potential. Consequently, the Weather Research and Forecasting model with chemistry (WRF-Chem) was applied to current (2016-2020) and future (2046-2050) under the shared socio-economic pathways (SSP) 2-4.5 scenario to investigate the impact of future meteorological conditions and emission reductions on solar energy potential. The evaluation of the WRF-Chem demonstrates satisfactory performance in capturing most meteorological and chemical variables at a climatological scale. However, the model underestimates 2 m temperature while overestimating 2 m specific humidity and 10 m wind speed, with mean bias (MB) of -0.1 degrees C, 1.4 g kg(-1), and 0.8 m s(-1), respectively. Additionally, the WRF-Chem overestimates PM2.5, with normalized mean bias (NMB) of -20%. The model underestimates cloud fraction and precipitation caused by the limitation in the cloud microphysical parameterization. The model well reproduced the solar energy distribution in China, with R of 0.76 and NMB of -3%. Looking ahead, the future annual average solar energy increases by 2.2, 0.1, 2, 4.1, 1.9, and 2.9 W m(-2) for China, Beijing-Tianjin-Hebei, Fenwei Plain, Yangtze River Delta, Pearl River Delta, and Sichuan Basin, respectively. The future annual average photovoltaic potential increase by 1-4% in these regions. This increase is primarily attributed to the increase in solar energy resulting from emission reductions (4.7, 5.1, 5.0, 4.7, 3.2, and 6.1 W m(-2)), which outweighs the decrease caused by meteorological conditions (2.5, 5.0, 2, 4.1, 1.9, and 2.9 W m(-2)). Hence, emission reduction plays a vital role in promoting solar energy utilization.