The Tennessee Valley Authority proposed replacing its 2,522-MW Cumberland coal-fired plant with natural gas in a draft report released April 25.

The federal power authority, known as the TVA, prepared the environmental impact statement to evaluate the environmental and social effects of retiring and demolishing the two Cumberland units and adding at least 1,450 MW of replacement generation.

The TVA evaluated three alternatives for replacing the generation lost as a result of retiring one Cumberland unit: a combined-cycle combustion turbine gas plant at the Cumberland site; two simple-cycle combustion turbine gas plants at alternate locations; or multiple solar generation and energy storage facilities at alternate locations primarily in middle Tennessee.

Keeping the two Cumberland units running would require additional repairs and maintenance for reliability, according to the report, and ultimately the TVA favors shutting down the plant "as financial and system analysis indicate a [combined-cycle] gas plant is the best overall solution to provide low-cost, reliable and cleaner energy to the TVA power system," the 478-page report reads.

The first of the two Cumberland units could retire as early as 2026 but no later than 2030, according to the TVA proposal. The second unit would retire as early as 2028, but no later than 2033.

The TVA's plans for Cumberland have not been finalized. In November 2021, the TVA board of directors handed over authority to President and CEO Jeff Lyash to make a final decision on the fate of the Cumberland and 1,420-MW Kingston plants. Lyash is expected to report back to the board prior to making his decision but is not required to bring a recommendation to the board for a formal vote. The environmental impact statement for the Kingston plant has not yet been released publicly.

TVA will take public comments on the proposal through June 13 and will hold public meetings about the future of the coal plant beginning in May.

The Cumberland plant — one of the 10 largest coal plants in the U.S. — began service in 1973, according to S&P Global Market Intelligence data. Kingston came into service in 1954.

TVA executives have previously outlined plans to phase out the coal fleet by 2035, with gas and small modular nuclear reactors replacing that generation.

The TVA has a goal of net-zero carbon emissions by 2050. A TVA spokesperson previously confirmed the federal wholesale power authority assumes that Cumberland and Kingston, along with the 1,242-MW Shawnee and the 988-MW Gallatin facilities, will not be viable generation sources by 2035, the same year by which President Joe Biden aims to decarbonize the U.S. power grid.

"The aging TVA coal fleet is among the oldest in the nation and is experiencing deterioration of material condition and performance challenges ... projected to increase because of the coal fleet's advancing age and the difficulty of adapting the fleet's generation within the changing generation profile," the TVA stated in its proposal. "The continued long-term operation of some TVA coal plants, including the Cumberland Fossil Plant, is contributing to environmental, economic and reliability risks."

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