Staff File Photo / The TVA office building in downtown Chattanooga serves as the federal agency's power headquarters.

The Tennessee Valley Authority could become one of the first utilities to pioneer a new smaller nuclear reactor design that developers hope will be simpler, cheaper and safer than existing nuclear power plants and could be critical in helping the nation's biggest government utility to become carbon free with its power generation.

TVA is the first U.S. utility to obtain an early site permit for a small modular reactor proposed to be built on the Clinch River in Oak Ridge. TVA is studying the feasibility of building several small reactors on the Oak Ridge site — and ultimately others on other abandoned power plant locations in TVA's seven-state region — to help replace power generation from TVA's aging fleet of coal-fired power plants.

But TVA CEO Jeff Lyash wants a partnership with other industry players and federal support if it is to be a first-of-its-kind developer for the new smaller modular reactors.

"TVA will not go this alone," Lyash told an American Nuclear Society conference last week. "There is always a higher cost for first-of-a-kind technologies, but for TVA we cannot ask our customers to bear that first-of-a-kind premium. I think there is a very clear role here for the federal government in order to encourage development and support for this promising technology."

Lyash noted that one 300-megawatt small modular reactor built in Oak Ridge by TVA could generate enough carbon-free electricity to ensure that all of the federal facilities in the Tennessee Valley are net- zero emitters of any greenhouse gas emissions linked to global climate change.

The Biden administration is urging federal agencies to become carbon free in their own energy use in the next decade and a half and environmental groups like the Southern Alliance for Clean Energy are pushing TVA to become carbon free by 2030. The Oak Ridge National Laboratory and its affiliated military facilities currently generate 31% of all of the carbon output of all U.S. Department of Energy facilities. A small modular reactor could supply all of the power needed for the Oak Ridge reservation with carbon free electricity and still supply power for other major federal facilities in the Tennessee Valley, including the Redstone Arsenal and U.S. Space and Rocket Center in Huntsville, Alabama and the Arnold Air Force Base on Tullahoma, Tennessee.

TVA is already working with the Department of Energy and the University of Tennessee to help consider new small modular reactor designs.

Lyash said the technology for small light-water reactors is already proven, although TVA has yet to select a specific design and builder if it decides to move ahead with building SMRs in Oak Ridge. Lyash said the challenge will be in deploying the design and building the units on schedule and on budget.

Construction costs go nuclear

TVA completed the last new commercial nuclear reactor to be added to American's power grid in 2016 when TVA finished its second unit at the Watts Bar Nuclear Power Plant near Spring City, Tennessee more than 40 years after construction initially began. When TVA decided to resurrect the work on the unit, it estimated the reactor could be finished for $2.5 billion but the final cost topped $4.7 billion.

Construction delays and cost overruns at the only new nuclear plant now under construction — units 3 and 4 at the Vogtle plant in Georgia — have more than doubled the cost of the new units to over $20 billion.

Nuclear power critics insist that nuclear power is too costly and risky as a way to control greenhouse emissions that contribute to global climate change. Stephen Smith, executive director for the Southern Alliance for Clean Energy, said the radioactive dangers from nuclear power and the cost overruns on new plant construction should convince TVA not to pursue more nuclear power, although his group is not pushing for any immediate shut down any of TVA's existing nuclear power plants.

"There is a significant amount of carbon-free energy that is being generated by existing nuclear reactors and it is not an easy decision to just flip the switch off on all the existing reactors," Smith said. "But we need to be looking at moving away from the nuclear technology in the longer term and we are certainly not fans of SMRs (small modular reactors) which remain unproven at this point."

Lyash, a nuclear engineer who formerly worked at the U.S. Nuclear Regulatory Commission, said new technologies in nuclear power and carbon sequestration will be needed to move TVA to a completely carbon-free generating source of electricity, especially as power demand may grow again as electric vehicles replace gas-powered cars and trucks. TVA has been exploring the possibility of siting a small modular reactor at the Clinch River site since 2014 and acquired an Early Site Permit from the NRC in 2019.

TVA pioneers new emergency zones

But the TVA board has not authorized building any new small modular reactors as yet. TVA was recognized last week by the Nuclear Energy Institute for its work to engage the public in the issue of a right-sized emergency planning zone for potential small modular reactors in Oak Ridge. TVA was selected by NEI for a Top Innovative Practice award for its work on the site preparations and potential deployment of the new reactor design.

"Technology innovation is part of TVA's mission," said Dan Stout, TVA director of nuclear technology innovation. "Maintaining positive engagement with the public is important for our long-term success in exploring new nuclear technology and the innovation that will make it possible."

For more than 40 years, regulations on reactors like those used by TVA and other utilities to generate electricity have required a 10-mile emergency planning zone. Smaller, advanced nuclear reactor designs do not require as large a zone.

Following TVA's work to engage the public and community leaders in learning about safe and economical emergency planning zones, the NRC approved this method for the Clinch River site application.

"TVA's work paves the way for others in the nuclear sector to potentially implement scalable emergency planning zones, with some already using TVA's model to develop their own approaches for emergency planning zone applications," said Stout.

TVA representatives actively sought public input in the project and provided immediate feedback. TVA also offered bus tours of the Clinch River site.

"We've established a relationship with plant neighbors and look forward to maintaining that relationship long-term as we explore advanced nuclear for the Clinch River site," Stout said.

Contact Dave Flessner at or 423-757-6340.