Find data and information the top global power plants.  In the US, the correspondence is generally great between variations and trends in OMI NO₂ levels and power plant NO_x emissions reported to the Continuous Monitoring Emissions System (CEMS).  However, there are many factors that can influence NO₂ levels above a power plant, including changes in regional background levels, other nearby sources, etc. See Duncan et al. (2013) for a detailed discussion on this topic.