Tennessee Valley Authority
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 the developed countries.
Sulfur dioxide is a respiratory irritant that can be harmful 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 power plants
Click chart for raw data
What TVA is doing about SO2 emissions
TVA is switching to low-sulfur coal at some fossil plants and has equipped 30 percent of its coal-fired capacity with scrubbers to reduce SO2 emissions. The scrubber on Unit 3 at Paradise Fossil Plant is under construction and scheduled for completion in 2006. Engineering studies and planning have begun for four scrubbers at Kingston, Bull Run, and Colbert Fossil plants.
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 reduction in the light of evolving emission reduction requirements. Those efforts have led TVA to make two changes in its plan to lower sulfur dioxide emissions.
The first is delaying the construction of the scrubber on Unit 5 at Colbert. This will allow TVA to focus its construction on plants in the eastern part of the Valley and allow a more cost-effective approach to the construction of scrubbers at Colbert.
Second, TVA will begin switching to lower sulfur coal at Johnsonville Fossil Plant at the beginning of 2005, which is earlier than originally planned.