The Tennessee Valley Authority is planning to build a natural gas plant in central Mississippi to meet its growing power load and make up for the coal plants the utility is shutting down across its seven-state region.
In a public notice issued last week, TVA said it is seeking public comments on a plan to build six natural gas-fired combustion turbines in Lowndes County, Mississippi, just northeast of Columbus, on the site of a former gas power plant dismantled by its private owner in 2007. Collectively, the six new generators proposed by TVA would be able to produce 500 megawatts of power, or about 40% of the power output of each of the reactors at TVA's Sequoyah Nuclear Power Plant.
The Mississippi facility would be the eighth gas-fired plant to be added to the TVA power system in the past three years to help TVA to replace power being lost by the shutdown of its coal-fired plants and the increased growth in the Tennessee Valley since the pandemic began.
"Since the pandemic, TVA has seen a strong increase in electric demand," the utility said in a notice of its plans for the new Mississippi power plant. "Current system modeling shows that with increased in-Valley residential migration and commercial development, TVA must add generation capacity to the system to maintain adequate operating reserves."
Despite President Joe Biden's goal of making the U.S. electric grid carbon free by 2035, TVA said it must continue to use some fossil fuel generation to meet its power demand, especially when hot temperatures boost air conditioning use or cold weather boosts electric heating in the Tennessee Valley.
TVA said the population and power demand in the TVA service region is growing by more than 1% a year. While power demand grows, TVA shuttered its Allen Fossil plant in Memphis in 2018, shut down its last Kentucky coal generator in 2020 and closed its last unit at the Bull Run Fossil Plant near Claxton, Tennessee, last Friday. TVA has pledged to phase out the last of the 59 coal-fired generators it once operated by 2035.
In an interview Tuesday, TVA President Jeff Lyash said the utility provider needs more power generation that can be quickly activated to meet demand peaks, especially when the sun doesn't shine, the wind doesn't blow or a nuclear unit is suddenly taken offline.
"We're building our renewables and battery storage as fast we we can, but it's not enough to support the economic growth that we are seeing and allow us to retire our older coal plants," Lyash said in an interview at the site of a new small modular nuclear reactor TVA also is proposing to build in Oak Ridge, Tennessee. "Gas is a bridge fuel for us."
TVA started up a $500 million gas plant at its former Colbert coal plant in Alabama in July, and the utility expects to start up a similar 750-megawatt, gas-fired turbine plant at the former Paradise coal plant in Kentucky later this month. Such gas units produce only a fraction of the carbon emissions of the coal plants they're replacing, Lyash said.
"Both Colbert and Paradise will end up being finished ahead of scheduled and under budget," he said.
Environmental critics of TVA question the billions of dollars TVA is spending for more natural gas plants, which produce both carbon and electricity and will need to run for many years in the future to justify their costs. In a recent report, the Sierra Club said TVA is building more new natural gas generation than any other U.S. utility, with nearly 6,000 megawatts to come from gas-fired power plants and pipelines by 2030.
"Methane gas is a dirty fossil fuel that's 80 times more powerful than carbon dioxide over a 20-year time frame and a major contributor to the climate crisis," the Sierra Club said in its report on "The Dirty Truth About Utility Climate Pledges."
Amy Kelly, a field organizer for the Sierra Club in Tennessee, also questioned TVA's claims about natural gas plants improving power reliability since TVA's biggest natural gas plant, the Cumberland Fossil Plant near Nashville, froze up and didn't deliver power during Winter Storm Elliott on Christmas Eve last year, forcing TVA to impose rolling power blackouts for the first time in its 90-year history.
"The blackouts were caused by failing gas and coal infrastructure," Kelly said in a statement. "You would think TVA would be reconsidering its plans to build out so much gas. But instead, they're doubling down and adding even more."
TVA said it has upgraded its equipment and instruments for colder weather in the past year so an incident like the one during Winter Storm Elliott would no longer shut down its gas plants or cut off power deliveries.
But Stephen Smith, executive director for the Southern Alliance for Clean Energy, said a better way to respond to the energy market would be to encourage more conservation, efficiency, and distributed energy production and storage.
"TVA is powering through with brute force to build more gas generation instead of working on ways to encourage and promote energy demand and efficiency from consumers," Smith said.
TVA is taking public comments on its plan for the new Mississippi plant until Jan. 19 and will conduct a public open house about the project from 5-7 p.m. Jan. 8 at 205 South St., Caledonia, Mississippi. TVA will take such comments and then prepare an environmental assessment of its energy options, Lyash said.