Emissions Continue to Drop Throughout PJM Footprint

CO2, SO2 and NOX Remain on Downward Path, Continuing Multi-Year Trend


Average emissions rates fell again in 2019 across PJM’s footprint of 13 states and the District of Columbia, continuing their steady, 15-year decline.

Since 2005, the carbon dioxide emissions rate has dropped 34 percent, the emissions rate from nitrogen oxides has dropped 83 percent and the sulfur dioxide emissions rate has dropped 94 percent. PJM compiles annual emissions statistics and issues a detailed analysis of emissions rates in the spring.

2005–2019 PJM Average Emissions Rates

PJM’s wholesale electricity markets have encouraged the investment in, and entry of, new, more efficient technologies. New supply resources – including cleaner, more efficient generators, renewables, demand response and energy efficiency – are replacing older, less efficient resources. This trend has contributed to the decline in emissions rates over both the long term as well as year over year. The carbon dioxide emissions rate dropped 8 percent between 2018 and 2019, while the nitrogen oxides emissions rate dropped 15 percent and the sulfur dioxide emissions rate dropped 22 percent.

Average Emissions Rates 2019 (lbs/MWh)Average Emissions Rates 2018 (lbs/MWh) Percent Drop
Carbon Dioxide851.19924.268%
Nitrogen Oxides0.450.5315%
Sulfur Dioxide0.550.7022%