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Nuclear power represented just thirty one percent of TVA’s power mix in the first nine months of the current fiscal year. TVA has not reported a share of nuclear power that low since 2007, when the utility was sixty-four percent coal, thirty percent nuclear, six percent hydroelectric and less than one percent gas or renewable during that fiscal year. TVA had its lowest use of nuclear power since 2007 between the 1^st 2024 and June 30^th 2025.

TVA’s power mix caused more air pollution and planet-warming emissions that normal this past year due to increased fossil fuel burning. Mining or drilling for methane and coal releases methane into the atmosphere, pipelines transporting methane leak, and burning coal and methane at power plants releases carbon dioxide and other toxic air pollutants. TVA’s fossil fuel plants are among the biggest single-source climate polluters in Tennessee. The Cumberland and Gallatin plants consistently rank as the top two, according to the U.S. Environmental Protection Agency.

The nuclear plant outages have likely increased monthly bills for residents across the valley. Forced outages caused TVA to use more expensive fuels.

TVA bought more fuel in the form of methane and coal, instead of uranium, and more natural gas-fired power from other companies this past year. TVA was forced to buy more expensive power than it would have if the nuclear reactors had been operational.

TVA initially denied that the outages raised utility bills. The utility said that fuel costs went up because of the outages and fuel costs affect how local power companies like the Nashville Electric Service charge monthly bills to customers. Unplanned outages can be especially costly during extreme heat or cold events, such as when the entire Sequoyah plant failed during a heatwave in July of this year.

Scott Brooks is the TVA spokesperson. He said, “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 fiscal year 25 so far.

While TVA may have been able to fill in the lost power, a high number of outages is a reliability concern, according to Allen, the professor.

During the Sequoyah outage in July of this year, for example, TVA activated its “emergency load curtailment program” and asked residents to voluntarily lower their energy usage hours after the reactors failed without disclosing the outages.

Allen said, “If you take a reactor down, that’s a lot of capacity that you take down.”

Over this past year, state officials and folks in the power industry have been watching the utility’s other nuclear developments, because TVA may play a big role in the next generation of nuclear reactors. In May of this year, TVA became the first utility to ask the Nuclear Regulatory Commission for a construction permit for a small, modular reactor in Oak Ridge. Prominent state Republicans, including Governor Bill Lee and Senators Marsha Blackburn and Bill Hagerty, have all pushed for a fast expansion of new nuclear plants in editorials this year.

Nuclear Regulatory Commission

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Putin speaks on oil, gas, coal and nuclear at Russian Energy Week reuters.com

Radiant to locate microreactor factory in Tennessee world-nuclear-news.org

New Duke Energy plan adds nuclear and extends coal, but drops wind to meet surging demand starnewsonline.com

Latitude 47.704656 Longitude -122.318745

Ambient office = 129 nanosieverts per hour

Ambient outside = 104 nanosieverts per hour

Soil exposed to rain water = 100 nanosieverts per hour

Green onion from Central Market = 93 nanosieverts per hour

Tap water = 72 nanosieverts per hour

Filter water = 60 nanosieverts per hour

Part 1 of 2 Parts

Commercial nuclear power plants are usually the Tennessee Valley Authority’s biggest source of electricity. However, this source of electricity plummeted this past year because outages plagued all seven reactors owned by the utility.

TVA reported fourteen unplanned or maintenance outages over a thirteen-month period, according to a review of data from the U.S. Nuclear Regulatory Commission. TVA has not responded to multiple requests for comments to verify the number of outages. At least twelve of the outages were “forced,” meaning they were unplanned, while two were planned for maintenance purposes.

The longest outage occurred at TVA’s Sequoyah Nuclear Plant in Soddy-Daisy, Tenn., which has two reactors. The main generator of the second reactor failed in July 2024. TVA undertook additional nuclear life extension projects during the extended, eleven-month outage, and the new generator is expected to last another forty years, according to TVA spokesperson Scott Fiedler. On June 24^th 2025, just one day after TVA brought this reactor back online, the entire nuclear plant failed because of a cooling water shortage during a heatwave.

Tim Rausch was the TVA’s top nuclear official. Two weeks later, on the same day as a forced outage at the Watts Bar Nuclear, Rausch resigned. Rausch joined TVA in 2018 and managed the entire nuclear fleet, making fourteen million dollars between fall 2018 and fall 2024, according to the utility’s financial filings to the U.S. Securities and Exchange Commission. Rausch plans to step down by March 2026, halfway into the next fiscal year.

TVA reported twelve unplanned nuclear outages to the Nuclear Regulatory Commission between July 2024 and August 2025.

Occasional nuclear outages are not especially unsafe. None of these outages were directly related to the nuclear reactors.

Todd Allen, a professor of nuclear engineering at the University of Michigan said, “The fact that it’s a forced outage doesn’t mean danger. Sometimes it can be as simple as a piece of critical equipment fails to operate as normal.” However, outages are a risk to reliability and costs.

TVA owns seven nuclear reactors among the Sequoyah, Watts Bar and Browns Ferry plants. The plants together account for about one fifth of TVA’s total energy capacity. TVA generally keeps its nuclear plants in constant operation, except when refueling uranium, so nuclear is usually about forty percent of the utility’s total energy use in a normal year. This year, nuclear power dropped to lowest share of the energy mix since 2007.

But the use of nuclear power dropped by about thirty percent between the 1^st of September 2024 and June 30^th 2025 compared to the same period the year before, according to TVA. The utility replaced more than ninety percent of that lost power with fossil fuels.

Tom Rice is the TVA’s chief financial officer. He said, during a board meeting in August, “That generation was offset with natural gas, purchased power, which is primarily natural gas, and very strong performance by the coal fleet this year.”

Tennessee Valley Authority

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Paks II equipment supply approved, Rosatom says world-nuclear-news.org

Long-term safety at Armenian plant assessed world-nuclear-news.com

Dismantling of Hamaoka 1 reactor under way world-nuclear-news.org

Latitude 47.704656 Longitude -122.318745

Ambient office = 108 nanosieverts per hour

Ambient outside = 87 nanosieverts per hour

Soil exposed to rain water = 86 nanosieverts per hour

Corn from Central Market = 136 nanosieverts per hour

Tap water = 82 nanosieverts per hour

Filter water = 74 nanosieverts per hour

Part 2 of 2 Parts (Please read Part 1 first)

Maksym Protsenko is the head of the engineering center at Chernobyl nuclear power plant. He said that before the drone damage, the next steps which were being planned for the NSC were designing, procuring and then dismantling the original – now unstable – 1986 shelter and “the development of technologies for and retrieval of fuel-containing materials and long-lived radioactive waste” from the original shelter, “followed by their conditioning, storage and final disposal”.

All of this work had to be put on hold, and he outlined the scale of the damage. The impact site suffered “pass-through damage to an area of eighteen square yards”; damage to cladding from the fires that continued to smolder afterwards in an area of about three hundred and forty square yards; technological equipment including the power supply system, ventilation and control systems damaged by “drone fragments and blast wave”; the membrane, designed to help ensure the tightness of the shelter to protect the external environment, smoldered and more than three hundred and forty holes had to be cut in the shelter to allow firefighters to put out the fires. In addition, there was also damage to the steel structures of the arch and crane systems.

The IAEA’s, Martin Gajdos is the IAEA Technical Coordinator of the Department of Nuclear Safety and Security. He said that the damage meant the New Safe Confinement “is currently unable to perform its confinement function”, although he stressed that there had been no change in measured radiation levels compared with prior to the drone strike.

Protsenko said that inspections and assessments had been taking place with the aim of drawing up estimates for a repair plan. However, this would take time and so there was therefore a need to go ahead with temporary repairs to protect the structure from further weather-related damage.

Steven White is from the European Bank for Reconstruction and Development. He said that its continuing support and work at Chernobyl was now focused on the urgent need for repairs to the New Safe Confinement. He mentioned that repair costs were estimated to exceed one hundred and eighteen million dollars.

He explained that the extent of the damage was “severe and complex” and warned that “full restoration under original design was unlikely … difficult choices lie ahead”. He praised the financial contributions in the past few months from the European Union, France and the UK and appealed to the international community to continue its support, commenting that Chernobyl “remains one of the world’s most fragile nuclear facilities”.

Oleg Korikov is the Director General of the State Nuclear Regulatory Inspectorate of Ukraine. He said that between 2005 and 2008 emergency stabilization measures had been put installed for the original shelter to reduce “the risk of the shelter collapse and potential large release of radioactive dust to the atmosphere”. They were intended to last for up to fifteen years and allow for dismantling to take place once the New Safe Confinement was in place and commissioned, by 2023. However, he said, that work has not happened and with the current state of the New Safe Confinement “planned measures for the Shelter Object unstable structures dismantling are impossible”.

The New Safe Confinement work was financed by the Chernobyl Shelter Fund which was run by the European Bank for Reconstruction and Development. It received about 2 billion dollars from forty-five donor countries and the EBRD provided five hundred and sixty-two million dollars of its own resources.

Chernobyl New Safe Confinement

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Largest load transported along ITER itinerary world-nuclear-news.org

Latitude 47.704656 Longitude -122.318745

Ambient office = 87 nanosieverts per hour

Ambient outside = 129 nanosieverts per hour

Soil exposed to rain water = 130 nanosieverts per hour

English cucumber from Central Market = 93 nanosieverts per hour

Tap water = 64 nanosieverts per hour

Filter water = 53 nanosieverts per hour

Part 1 of 2 Parts

The 69^th International Atomic Energy Agency (IAEA) General Conference was recently held in Vienna. Representatives from the IAEA’s one hundred and eighty Member States convened from the 15^th to the 19^th of September at the Agency’s headquarters in Vienna, Austria. Addressing the Board of Governors before the Conference, IAEA Director General Rafael Mariano Grossi emphasized how the IAEA is supporting the priorities of its Member States through peaceful uses of nuclear science and technology. He said in an introductory statement, “The Agency has made significant progress across its flagship initiatives, advancing nuclear technologies to address global challenges in health, food security, environmental sustainability and climate resilience.”

During the conference, delegates will discuss a range of topics, ranging from the 2024 Annual Report and the 2026 budget to activities related to nuclear science, technology and applications, as well as the IAEA’s nuclear safety and security activities and strengthening the effectiveness and improving the efficiency of Agency safeguards. They will also discuss other topics such as nuclear safety, security and safeguards in Ukraine and safeguards in the Middle East and in the Democratic People’s Republic of Korea. Sessions held in the Plenary Hall, including the statements of officials and delegates, will be livestreamed for the public.

A side event will be held on the topic of damage to and repair of the Chernobyl containment vessel. The arch-shaped New Safe Confinement structure built over the remains of Chernobyl’s destroyed Reactor 4 suffered such extensive damage in a Russian drone strike last February that it may not be possible to restore it to its full original design purposes and life-span of one hundred years.

Chernobyl Reactor 4 was destroyed in the April 1986 accident with a shelter constructed in a matter of months to encase the damaged reactor, which allowed the other reactors at the plant to continue operating. The ruins on the site still contain the molten core of the reactor and an estimated two hundred tons of highly radioactive material.

However, the shelter was not designed for the very long-term, and so the New Safe Confinement shelter (NSC) was constructed to cover a much larger area including the original shelter. It is the largest moveable land-based structure ever built. The New Safe Confinement has a width of two hundred and eighty-one yards, a length of one hundred and seventy-seven yards, a height of one hundred and eight yards and a total weight of thirty six thousand tons and was designed for a lifetime of about one hundred years. It was built nearby in two halves which were transported on specially constructed rail tracks to the current position, where it was completed in 2019.

It has two layers of internal and external cladding around the main steel structure which are about thirteen yards apart. Both of these layers were breached in the drone attack. The NSC was designed to allow for the eventual dismantling of the deteriorating makeshift shelter from 1986 and the management and containment of radioactive waste. It is also designed to withstand temperatures ranging from minus one hundred- and nine-degrees Fahrenheit to plus one hundred- and thirteen-degrees Fahrenheit , a class-three tornado, and an earthquake with a magnitude of six on the Richter scale but it was not designed to withstand missile or drone strikes.

On the morning of February 14th of this year, a drone struck the New Safe Confinement shelter, with security cameras catching the explosion that took place on impact.

69th IAEA General Conference

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