Sulfur Dioxide

Sulfur dioxide (SO2) is a pollutant gas produced by various human activities, including ore processing, petroleum refining, the operation of industrial boilers and the burning of oil and coal at power plants. Although natural processes like volcanic activity and biological decay are responsible for half of the world’s atmospheric sulfur, emissions caused by human activity far exceed natural emissions in developed countries.

Sulfur dioxide is a respiratory irritant that can be harmful at high concentrations when breathed by people who are very young, very old or already suffering from health problems. It can also damage vegetation, corrode building materials and contribute to the production of airborne particulates and acid rain.

SO2 emissions at TVA plants, 1974-2022

Data includes emissions from units rated at less than 25 megawatts.
To view or export the data, click on the menu in the top-right corner of the chart.

What TVA is doing about SO2 emissions

TVA has reduced its sulfur dioxide emissions by 94 percent since 1977, in part by switching to low-sulfur coal at some fossil plants and equipping 60 percent of its coal-fired capacity with scrubbers. A second scrubber was installed at the Kingston fossil plant in 2010. The TVA board approved scrubbers at the Gallatin fossil plant in 2011, and TVA continues to upgrade and assess its entire fossil fleet.

TVA staff continue to look for better, more cost-effective ways to reduce TVA’s emissions while continuing to supply reliable, affordable electricity and manage debt in the light of evolving emission reduction requirements.