Managing China's coal power plants to address multiple environmental objectives
China needs to manage its coal-dominated power system to curb carbon emissions, as well as to address local environmental priorities such as air pollution and water stress. Here we examine three province-level scenarios for 2030 that represent various electricity demand and low-carbon infrastructure development pathways. For each scenario, we optimize coal power generation strategies to minimize the sum of national total coal power generation cost, inter-regional transmission cost and air pollution and water costs. We consider existing environmental regulations on coal power plants, as well as varying prices for air pollutant emissions and water to monetize the environmental costs. Comparing 2030 to 2015, we find lower CO2 emissions only in the scenarios with substantial renewable generation or low projected electricity demand. Meanwhile, in all three 2030 scenarios, we observe lower air pollution and water impacts than were recorded in 2015 when current regulations and prices for air pollutant emissions and water are imposed on coal power plants. Increasing the price of air pollutant emissions or water alone can lead to a tradeoff between these two objectives, mainly driven by differences between air pollution-oriented and water-oriented transmission system designs that influence where coal power plants will be built and retired.