Impacts of power generation on air quality in China-Part II: Future scenarios

Power generation is an important source of air pollution in China since it is mostly from coal-fired power plants. Future power generation plans are needed to meet both increasing power needs and air quality improvement. In this study, five future power development scenarios in 2030 were considered. The REF scenario is the base case in which the growth was assumed to follow the existing projection (business as usual). The CAP scenario represents power sector in the trajectory to achieve 80% reduction by 2050 as proposed by IPCC, the LOW scenario reflects low cost of renewable to foster wind and solar development, the PEAK scenario allows China to peak its carbon emission by 2030, while the WEST scenario assumes that the coal power bases build all planned capacity by 2030 and no coal power in Beijing, Tianjin and Shanghai by 2030. Then, impacts of the scenarios on air quality were simulated with the Community Multiscale Air Quality (CMAQ) model in January and August 2030 with unchanged emissions from other sectors and the same meteorology in 2013. The results indicate that air quality gets worse in the REF scenario in both months compared to 2013. The CAP and WEST scenarios generally have larger impacts on pollutant concentrations than the LOW and PEAK scenarios. The four scenarios improve PM2.5 total mass and SO42− in North China, with maximum decreases of over 100 μg m−3 in January and over 10 μg m−3 in August in the Hohhot area. However, PM2.5 total mass and SO42− pollution are worsened in Shandong for CAP and WEST scenarios and in Chongqing for LOW and PEAK scenarios. NO3− and O3 get worsened in the four scenarios in large areas of the North China Plain (NCP), East and South China due to more NH3 available for NO3− formation associated with reduction in SO42− and aerosol radiative effects on UV radiation for O3 formation. Power development plans greatly affect air quality in Beijing, with decrease in PM2.5 and PM10, but increase in O3. Reducing NOx and SO2 combined with NH3 should be considered to reduce contribution of power generation to future air pollution in China.