In Oak Ridge, the place where the first electricity from nuclear power was generated, the Tennessee Valley Authority is planning to build what may become the nation’s first mini nuclear plant. 

The federal utility has proposed constructing a “small modular reactor,” the industry term for a nuclear plant that is smaller than a conventional plant with parts manufactured in a factory. TVA has obtained some regulatory approval to build a 300-megawatt reactor, about a quarter of the capacity of one of the 1.1-gigawatt units at its nearby Watts Bar Nuclear Plant. 

Small modular reactors have the same basic technology as conventional nuclear reactors — heating water with uranium and feeding steam into a turbine. But the hope is that these little nukes will be easier and cheaper to build. 

“This is a gift that will keep on giving, to the country, to this region and to the world,” U.S. Energy Secretary Jennifer Granholm said last week during a press conference in Oak Ridge. 

The reactor will be built at TVA’s Clinch River site, contained on a 1,200-acre property in Oak Ridge, just outside of Knoxville. 

Caroline Eggers WPLN News

The Tennessee Valley Authority plans to build a 300-megawatt nuclear reactor at its Clinch River site in Oak Ridge.

In the 1970s, TVA tried to build a nuclear plant on the Clinch River property, but the plant ultimately proved too expensive. The project was canceled by the early 1980s. 

In 2016, TVA tried again. The utility submitted an application to the U.S. Nuclear Regulatory Commission for an initial permit to build two or more small modular reactor plants. The permit sets a maximum of 2.4 GW of capacity for the site. 

The commission approved TVA’s permit in 2019. This was the first time any utility was awarded a permit for small modular reactors in the nation. TVA published an initial environmental review last year for the project. 

The utility will start with one reactor: a GE-Hitachi BWRX-300 small modular reactor, with a capacity for 300 MW, or .3 GW, of power. Construction could start as early as 2026, and the plant could come online by the early 2030s. 

If successful, TVA will try to build more nuclear plants across the state and Valley. 

“TVA is working to identify other nuclear sites across our footprint where we could then follow on and deploy multiple copies of this. How many, it depends on what the energy consumption is as we move into this decarbonized future,” said TVA CEO Jeff Lyash, who has previously said he is interested in 20 reactors.

How will this fit into federal clean electricity goals? 

Two years ago, the Biden Administration set a target of clean electricity by 2035 and a net-zero economy, meaning electrified buildings and transportation, by 2050. 

“Certainly, we’re going to need to add in the United States 200 gigawatts of nuclear power in order to meet that goal,” by 2050, Granholm said. 

For TVA, which is owned by the federal government and is supposed to follow federal orders, it is the 2035 target for clean electricity that matters. 

At best, TVA will have .3 GW of new nuclear power online by the early 2030s and could theoretically have more online by 2035. There is a possibility that TVA will have no new nuclear capacity by that time, however, given the pilot nature of the proposed Clinch River reactor. 

So, TVA cannot meet federal clean electricity goals by relying on new nuclear power alone. 

The most likely pathway to quickly reach 100% clean electricity is to rapidly deploy massive amounts of renewables, retire all fossil fuel plants and cut plans to build new fossil fuel plants. In the past three years, TVA has proposed constructing eight methane gas plants with a total capacity of 6.6 GW. TVA is also currently planning to get 10 GW of solar by 2035, so more would be needed to meet the administration’s goals.

More: TVA proposes 8th gas plant in 3 years | WPLN News

“TVA ratepayers shouldn’t be giving Lyash $10 million a year when he’s leading the nation’s largest planned gas buildout and worsening the climate emergency,” Gaby Sarri-Tobar, the energy justice campaigner at the Center for Biological Diversity, said in a statement. “Granholm has to demand much more from this Biden-appointed TVA board, including firing the CEO if he keeps defying the administration.”

Caroline Eggers WPLN News

Tennessee Valley Authority CEO Jeff Lyash speaks at a press conference at the Clinch River nuclear site in Oak Ridge on December 5, 2023.

WPLN News did ask Granholm how TVA’s gas plans fit in with federal clean electricity targets. 

“They’re going to focus on natural gas as a bridge,” Granholm said, repeating the common phrase coined by the fossil fuel industry. “I’m hopeful that they’ll keep their mind open about technology expansions in nuclear and clean hydrogen and energy storage and… solar.” 

Although TVA’s plan for new nuclear capacity might not come to fruition this decade, the technology may still be important for the clean energy future. 

Nuclear uses less land than renewables

The nation can have 100% clean electricity by 2035, according to a report published last year by the National Renewable Energy Lab, part of the U.S. Department of Energy — though that possibility is becoming increasingly unlikely.

In most scenarios, wind and solar provide most of the generation, up to 80%, for least-cost electricity mixes, and very little new nuclear is needed. 

“Technologies that are being deployed widely today represent the vast majority of the solution,” the NREL report authors wrote. “A 90% clean grid can be achieved at low incremental cost by relying primarily on new wind, solar, storage, transmission, and other technologies already installed today.” 

In a scenario where land is heavily restricted, however, nuclear capacity could double. The main benefit of new nuclear, as opposed to other clean energy sources, is land use. Nuclear uses about 100 times less land than ground solar and roughly 20 times less than the direct land use of wind energy. Fossil fuels disturb the most acres due to oil, gas and coal extraction. 

“If there are challenges with siting and land use to be able to deploy this new generation capacity and associated transmission, nuclear capacity helps make up the difference,” NREL said. 

Courtesy National Renewable Energy Lab

The National Renewable Energy Lab estimated the total land use required by wind and solar to reach 100% clean electricity by 2035.

But new nuclear could be part of the mix even under higher wind and solar scenarios. NREL estimates that newer tech, such as hydrogen and advanced nuclear, will be needed in the next decade but are not ready to be deployed at large scale. 

Nuclear is expensive — very expensive

Small modular reactors may require less construction time, financing costs and land than conventional nuclear plants and could be more easily duplicated, given the factory-assembled components. 

The primary concerns with the tech are nuclear waste and cost. 

Nuclear has historically been expensive. TVA has a $20-billion debt due to failed nuclear projects of the past.

The technology is still expensive today: Last month, a nuclear project in Idaho was canceled after construction costs rose from $5.3 billion to $9.3 billion for six small modular reactors. 

Earlier this year, the utility Georgia Power finished constructing the first of two units for a 2.2 GW conventional nuclear plant called Vogtle, seven years behind schedule. This plant was estimated to cost $14 billion, but the final tab may total $35 billion. For the same amount of power, the construction of a solar-plus-storage system might cost between $4 and $5 billion. 

Further back, TVA tried building a nuclear plant at the Clinch River site. It was estimated to cost $400 million in 1971, but the cost rose to $8 billion and the project was canceled in 1983. 

TVA gets its money by selling electricity to customers, so customers pay the costs of construction for new power plants. For example, TVA is spending $15 billion on capital projects in the next three years, largely for its planned — but not fully approved — fossil fuel expansion, which is why electricity bills have gone up.

Who is supporting the Clinch River project?

Broadly, support for new nuclear may be thin, but state and federal officials have announced support. Gov. Bill Lee and U.S. Rep. Chuck Fleischmann, a Republican who represents Oak Ridge, have publicly backed the project. 

The U.S. government will also prop up the industry via tax credits through the Inflation Reduction Act.