Impact of a national plan for future electricity supply on ambient air quality in South Korea

South Korea has recently chosen coal as the major energy source for the future national electricity power supply, mainly due to economic reasons. This has raised concerns about national air quality, considering the serious air pollution associated with the long-range transport of Chinese air pollutants. In the present study, we simulated air pollution levels for 2027 considering the changes in electricity power plants of South Korea proposed by the sixth Basic Plan for Long-Term Electricity Supply and Demand (6th BPE, 2013-2027). Compared to the emissions in 2010, the emissions of CO, NOx, SOx, and PM10 from electricity supply in the Incheon, Gyunggi, Gangwon, Chungnam, and Gyeongnam regions will increase by 20-50% in 2027. The resulting number of days on which pollution levels exceeded the national air quality standards for O3 and PM10 will increase by fewer than 6 days in all regions, which seems to be a minor increase. However, that of NO2 over the Seoul metropolitan area (SMA, including Incheon, part of Gyunggi, and Seoul) showed a marked increase of more than 21 days. Therefore, an impact from secondary air pollution, such as acid rain and PM2.5 formation, can be expected, although this requires quantification.