Sunlight shining down from 93 million miles away. Wind blowing across a grassy plain. Methane gas seeping from decaying matter. These sources of abundant, fossil-free energy form a small but growing part of the power mix as TVA embraces renewables as a part of its vision to provide low-cost, cleaner energy for the future.
That’s why we created our Valley Renewable Energy program—to provide various ways for Valley residents and businesses to join us in supporting renewable resource energy projects in the Tennessee Valley and promote a greener energy future. Or, for a simple investment of $4 a month, you can invest in one block of Green Switch for your home or business, which will ensure that 150 kilowatt-hours of renewable energy is added to the grid.
Our key renewable sources include:
Solar is one of the cleanest sources of energy available. And for now, it’s also one of the most expensive.
TVA has started programs such Distributed Solar Solutions to encourage solar power production throughout the Valley. We opened 20 megawatts of solar capacity at the beginning of 2016 to support our green power mix and demonstrate our commitment to this promising technology.
How it works: Solar panels are mounted on rooftops or integrated into shingles or other building materials. When sunlight hits the cells, the electrons inside gain more energy and create an electrical current. Inverters then change the direct current into the alternating current used in homes and businesses.
TVA debuted the first commercial-scale wind project in the Southeast in 2001—then by popular demand expanded it in 2004. Buffalo Mountain, on a two-mile ridgeline near Oak Ridge, Tenn., has the capacity to generate 27 megawatts of electricity. Read more about TVA’s wind installation at Buffalo Mountain.
TVA also buys wind energy from nine wind farms throughout the Midwest, adding 1,542 megawatts of additional wind energy to its power portfolio.
Wind energy creates no air pollution and minimally impacts the environment, as long as turbines are placed carefully. Some turbines even double as communication towers for cell phones and other transmissions.
How it works: Wind turns the blades, which then turn an efficient generator to produce electricity. Winds as little as 10 miles per hour generate electricity. The turbines reach full capacity with 25-mph winds.
Methane gas—produced when organic waste decays—is actually a potent greenhouse gas if released directly into the atmosphere, with global warming effects more than 20 times that of carbon dioxide.
That means our innovative methane gas recovery project in Memphis yields two benefits:
- Diminishing global warming effects by collecting and using methane gas that otherwise would release into the atmosphere.
- Eliminating the need for more than 8,000 tons of coal per year, reducing air pollution while producing 5 megawatts of power production.
How it works: Wastewater treatment plants typically burn the methane gas released by decaying waste to avoid a hazardous build-up. In Memphis, we covered the wastewater treatment plant’s lagoon to capture the gas. The methane (sometimes called landfill gas or biogas) is then fired along with natural gas at the Allen Fossil Plant, which produces electricity and reduces methane’s global warming effects.