TVA’s most unique hydro asset – Raccoon Mountain Pumped Storage Plant – is undergoing a major turbine replacement in each of its four units. The upgrade will add approximately 20 megawatts per unit, which can power an additional 11,700 homes across the Valley.

The upgrade requires the removal of the massive 79-ton turbine impeller during a 268-day outage. In addition, the TVA team is replacing the old six-blade design with a new, more efficient and flexible state-of-the-art design, manufactured in the USA.

“The new design will reduce vibrations, improve reliability and increase the pumping and generating capacity of each unit,” said Jeremy Goodman, mechanical engineer, Hydro Generation. “Unit 4 was completed in 2019 with Unit 3 currently in outage. We plan to have Units 1 and 2 upgraded by the end of 2023 with a total of an additional 80 megawatts added to the system.”

This work is all thanks to the collaborative effort of a diverse team.

“We are grateful for the powerful partnerships across TVA and our vendors to successfully complete each and every outage,” said Michelle Ray, Raccoon Mountain Pumped Storage Plant Senior Manager.

Once the turbine upgrades are complete on all four units, TVA will be powering an additional 46,800 homes with clean, renewable energy. As an added benefit, the major upgrade will also prolong the life of the units for another 20 years.

“Extending the life of our hydro generating units is pivotal to building the energy system of the future,” said David Bowling, vice president, Gas & Hydro, Power Operations. “As we strive for cleaner energy, hydro is the original green power that we are investing in to power the Valley for decades to come.”