Air Quality

As part of its role of being a good steward of the Valley’s natural resources, TVA has one of the most aggressive clean air control programs in the country.

Some Highlights of TVA’s Program Include:

• TVA has reduced emissions by idling or retiring coal-fired units and relying more on cleaner energy resources including natural gas and nuclear generation and renewable sources.
• From 1970 - 2023, TVA spent $6.8 billion to reduce air emissions.  
• To reduce SO2 emissions, TVA operates scrubbers on 17 of its coal-fired units and switched to lower-sulfur coal at certain coal-fired units.
• To reduce NOx emissions, TVA operates SCRs on 17 coal-fired units, operates low-NOx burners or low-NOx combustion systems on 20 units, optimized combustion on all 24 units, and operates NOx control equipment year-round when units are operating (except during start-up, shutdown, and maintenance periods).
• TVA has also retired 35 of 59 coal-fired units. Except for seven units at Shawnee, the remaining coal-fired units in the TVA fleet have scrubbers and SCRs. TVA plans to construct SCRs at four of the Shawnee units by the end of 2025 and is evaluating plans for the remaining three units.

Air Quality Standards

By investing in high technology emissions-cleaning technology, TVA has reduced sulfur dioxide (SO2) emissions by 99 percent since regulations began in 1977. Nitrogen oxide (NOx) emissions have been reduced by 97 percent since 1995. See how emissions have trended sharply downward over the years on our Carbon Dioxide,  Nitrogen Oxides, Sulfur Dioxide,  Ozone and Greenhouse Gases pages. Or view emissions data for every one of our fossil plants—from Ackerman to Widows Creek—on our comprehensive Air Quality Standards index. 

Technology for Quality of Life

TVA’s investment in clean air technology has quality-of-life payoffs for Valley residents. See how the SCRs and scrubber equipment works to clean the air while keeping fossil plants working to produce the energy the Valley needs to thrive.

Clean Air Act Agreements

Through an agreement with the EPA, several environmental groups and the states of Tennessee, Kentucky, Alabama and North Carolina, in 2011, TVA agreed to phase out some fossil-fired units and replace them with cleaner sources of power and energy efficiency measures. Read more about TVA's agreement with the EPA.