Coal

TVA to replace Kingston coal-fired units with natural gas, solar + storage

The Kingston coal-fired units have experienced a “significant decline” in material condition over the last five years.
TVA to replace Kingston coal-fired units with natural gas, solar + storage
(Kingston Fossil Plant. Source: TVA.)

Following a multi-year­ public process, the Tennessee Valley Authority has officially made the decision to retire its coal-fired units at the Kingston Fossil Plant and build an “energy complex” at the site by the end of 2027.

This was not unexpected, but the federal utility officially announced the decision Tuesday. Kingston’s nine coal-fired units at Kingston by the end of 2027. To replace that generation, TVA will build an energy complex that will house at least 1,500 MW of combined-cycle capacity with dual-fuel aeroderivative natural gas combustion turbines. The Kingston site would also include 100 MW of battery storage and up to 4 MW of solar generation.

TVA was originally considering either a natural gas plant or a solar + storage site, and said a combined-cycle plant paired with dual-fueled aero turbines would be the “best overall solution to provide low-cost, reliable energy to TVA’s power system, and could be built and become operational sooner” than the solar and storage. It ultimately decided to implement both, and the natural gas generation will be in operation prior to Kingston Fossil Plant’s retirement.

The idea was presented in TVA’s Final Environmental Impact Statement issued by the federal utility Feb. 16 after a public review process last year over how to replace the coal-fired units at Kingston.

“We have a detailed workforce plan in place to maintain coal plant expertise and provide opportunities for employees to evaluate options and prepare for next career steps,” said Kris Edmondson, TVA vice president of Power Operations. “The plan includes opportunities to transfer to other TVA locations where employee skillsets are needed, positions in other technologies offering training to support transition to a new job in TVA, and supporting employees interested in retiring.”

TVA says it will continue to evaluate the remaining coal fleet for retirement and replacement generation. To reduce operational, economic and environmental risks, TVA is anticipating retiring its entire coal fleet by the mid-2030s.

Kingston’s nine units can generate about 1.4 GW of electricity at capacity. The plant, located about 35 miles west of downtown Knoxville, entered operations in the 1950s.

TVA said frequent cycling of Kingston’s coal units, reflected in start-up and shutdown events, are currently averaging more than 85 times per year, which the utility said is outside the intended design of the plant.

This is resulting in “increased wear and tear, which presents reliability challenges that are difficult to anticipate and expensive to mitigate.”

TVA also said Kingston has experienced a “significant decline” in material condition over the last five years, including the need for repairs to the lower boiler drum, which the utility said are symptomatic of age-driven material condition failures which are difficult to proactively address.