Making electricity is a bit like creating a huge science project for school. You get all these materials together and mix them up to make something incredible, and then your mom gets on you to clean up the mess youve made in the kitchen.
You cant make anythinga science project, a cake or electric powerwithout having to clean up afterwards. For TVA that means finding ways to make power for millions of homes, schools, farms and businesses, and at the same time keep the environment clean and healthy.
Wheres the dirt?
Electricity looks pretty clean, right? You flip a switch and a light goes on. Whats so messy about that? Well, its the making of electricity that can create pollution. About a quarter of TVAs power is generated by the burning of coal. When coal burns, potentially dangerous chemicals like sulfur dioxide (SO2) and nitrogen oxides (NOx) are released into the air. (Read information from the U.S. Environmental Protection Agency about air quality.)
Clearing the air
To clean up the air while still providing everyone in the Tennessee Valley with electric power, TVA uses some pretty complex, expensive equipment.
So far TVA has spent around $6 billion to control the release, or “emission,” of chemicals from its coal-burning power plants. Here’s what it’s doing:
- TVA has put “scrubbers” on 60 percent of its coal-fired capacity. These scrubbers help clean up SO2. IN addition, TVA has switch to low-sulfur coal at some of its fossil plants. As a result, sulfur dioxide emissions have been reduced by 94 percent since 1977.
- The best weapon against NOx is something called a selective catalytic reduction system, or SCR. TVA has installed SCRs on 21 of its coal-fired units. As a result, emissions of nitrogen oxides have been reduced 91 percent since 1995.