The Tennessee Valley Authority (TVA), which serves more than 10 million people in Southeast USA, is facing criticism after data revealed its nuclear reactors shut down unexpectedly 12 times over the past year. According to a WPLN News review of US Nuclear Regulatory Commission (NRC) records, these outages affected all seven of TVA’s reactors, resulting in the lowest use of nuclear power the agency has reported since 2007.
TVA has the sixth highest generation capacity of any US utility company and the third largest nuclear power fleet comprising seven units at three sites. The Browns Ferry NPP near Athens, Alabama operates three boiling water reactors; Sequoyah NPP in Soddy-Daisy, Tennessee, has two pressurised water reactors (PWRs); and Watts Bar NPP near Spring City, Tennessee, also has two PWRs.
TVA reported 14 unplanned or maintenance outages over a 13-month period, according to WPLN. At least 12 of the outages were “forced,” meaning they were unplanned, while two were likely planned for maintenance purposes.
The longest outage, which lasted nearly 11 months, occurred at the Sequoyah. This led to the resignation in July of TVA’s top nuclear official, Tim Rausch – on the same day as a forced outage at the Watts Bar plant.
At Sequoyah, the main generator at the second reactor failed in July 2024. TVA undertook additional life extension projects during the extended outage, and the new generator should last another 40 years, according to a TVA spokesperson. However, just one day after TVA brought this unit back online, the entire NPP closed due to a water shortage during a heatwave.
TVA confirmed that the outages forced it to rely more heavily on natural gas and coal instead of cheaper uranium, and more gas-fired power from other companies. TVA initially denied that the outages impacted bills. Upon further questioning from WPLN News, the utility said that fuel costs went up because of the outages. “The forced outages caused TVA to use more expensive sources including natural gas and purchased power to maintain our industry-leading reliability. Fuel expenses are higher than projected for FY25 so far,” TVA spokesperson Scott Brooks said.
According to WPLN, TVA’s nuclear output dropped by about 30% between late 2024 and mid-2025 compared with the previous year with natural gas and coal filling more than 90% of that gap. “Fuel expenses are higher than projected for FY25 so far,” TVA spokesperson Scott Brooks said in a statement to WPLN News.
The nuclear plants collectively account for about a fifth of TVA’s total energy capacity and nuclear is usually about 40% of the utility’s total energy use in a normal year. However, nuclear use dropped by about 30% between 1 September 2024 and 30 June 2025 compared with the same period the year before, according to TVA.
Nuclear power represented just 31% of TVA’s power mix in the first nine months of the fiscal year. TVA had not reported such a low share of nuclear power since 2007, when the utility was 64% coal, 30% nuclear, 6% hydroelectric and less than 1% gas or renewables.
