The Tennessee Valley Authority said it will retire two aging coal-based generating stations and include more renewable energy in its portfolio to keep electricity affordable and meet consumers' needs going forward.

TVA plans to close its 1,150-megawatt Paradise Unit 3 by December 2020 and its 881-MW Bull Run Fossil Plant by December 2023. The Paradise unit began operating in western Kentucky in 1970 and Bull Run, near Oak Ridge, Tennessee, went online in 1967.

TVA has also released a draft Integrated Resource Plan with options to meet changing demand over the next 20 years. Its key observations include an expansion of solar energy starting in 2020, varying levels of gas and energy storage for reliability and the need for new capacity under every scenario studied. The draft plan is available for comment through April 8.

The plan "emphasizes the importance of flexibility in our generation in response to the changing energy marketplace," said Laura Campbell, TVA vice president of enterprise planning.

All 23 electric cooperatives in Tennessee receive power from TVA.

"TVA has a diversified generation mix, and they frequently make changes to their portfolio. We have no reason to question or dispute those decisions as long as they are based on economics," said Trent Scott, vice president of corporate strategy for the Tennessee Electric Cooperative Association in Nashville. "These are important decisions that can have significant impact on our co-ops and the consumers we serve. We do not want to see TVA influenced by politics or any other outside forces."

Bull Run and Paradise were older generating units facing fairly significant upgrades to remain efficient and meet environmental regulations, he added.

Yet TECA remains concerned about rate hikes planned by TVA. A wholesale rate increase of 1.5 percent on consumers' monthly bills took effect Oct. 1, 2018.

"TVA is aggressively focused on debt reduction. We are concerned about the impact that will have on ratepayers," said Scott. "We are encouraging TVA to take a measured approach and carefully consider the impact these rate increases will have on Valley consumers."

The TVA board of directors approved the coal plant retirements at its Feb. 14 meeting, where it also gave the go-ahead to new solar energy projects.

"Making decisions that impact employees and communities is difficult as we fulfill our commitment to keep power rates as low as possible," said TVA President and CEO Bill Johnson.

Johnson said the federally owned power provider has been working with solar developers for the past six months to add 674 MW to TVA's system.

"TVA and local power companies are partnering on research projects that will help us better address the desire for choice in energy while continuing the benefits of reliable, low-cost public power for the Valley," he said.

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TVA Approves Budget as Co-ops Take Issue With Rate Hikes