TVA announced Wednesday that it has added 500 additional megawatts of electricity to the power grid – enough energy to power almost 300,000 homes.
With the completion of the 10 new aeroderivative gas turbines at Johnsonville Combustion Turbine Plant, west of Nashville, the Johnsonville site can now provide more than 1,200 megawatts to TVA’s grid, which provides electricity to more than 10 million people across seven states.
Justin McBath, TVA senior project manager, noted that the new natural gas turbines are similar to the aerospace engines they evolved from. They are designed to ramp up and down quickly or be turned off when not needed.
“They have a fast-start option,” said Mr. McBath. “You can go from a cold engine to full power in five minutes, generating 50 megawatts per unit – and these will actually generate up to around 57 to 59 megawatts under the right conditions.”
He said these features make the new units highly flexible – ideal for meeting daily and seasonal peaks in electricity demand. Last month, these units were put to the test as the region experienced its first heatwave. The average system temperature on June 25 (96 degrees) was the same as June 25 a year ago — but TVA saw an approximate 500-megawatt increase in demand. The year-over-year power increase reflects population growth, economic expansion, and the integration of new electricity-dependent technologies.
“This project helps to support the continued growth and demand for electricity in the Valley by adding new generators on the system,” said Eric Grau, TVA vice president of Gas Operations. “And the added benefit of these generators in particular is to provide additional reliability.”
The Johnsonville aeroderivative turbines are the first of their kind for TVA, but they won’t be the last. Construction is already underway on 16 aeros at TVA's 1,500-megawatt energy complex on the site of Kingston Fossil Plant in Roane County.
Moving forward, TVA plans to build about 6,200 megawatts of new generation. Over 3,500 of those megawatts are already under construction – enough to power about 2 million homes.