Clean Air
Making electricity is a bit like creating a huge science project for school. You get all these materials together, mix them up to make something incredible, and then your mom gets on you to clean up the mess you’ve made in the kitchen.
You can’t make anything—a science project, a cake, or electric power—without 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.
Where’s the dirt?
Electricity looks pretty clean, right? You flip a switch and a light goes on. What’s so messy about that? Well, it’s the making of electricity that can create pollution. More than half of TVA’s 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 $4.4 billion to control the release, or “emission,” of chemicals from its coal-burning power plants. It will spend another $1.3 billion by 2010. Here’s what it’s doing:
- TVA is putting “scrubbers” on four of its plants where pollution control is most needed. These scrubbers help clean up SO2. When complete, these controls will reduce SO2 emissions by an additional 200,000 tons each year. That’s 85 percent lower than emissions were in 1977.
- The best weapon against NOx is something called a selective catalytic reduction system, or SCR. That’s a long name for a high-tech piece of equipment that zaps NOx and turns it into harmless nitrogen gas and water vapor. By 2005, TVA had lowered NOx emissions during the summer ozone season by 80 percent from what they were in 1995. This effort to knock out NOx is one of the biggest pollution control programs in the country.
Learn more about TVA and clean air here.
