Regulatory milestone for Wyoming advanced reactor

TerraPower submitted an application to the US regulator for a permit that would allow the construction of Kemmerer Unit 1 in Lincoln County, Wyoming, in March 2024. The first-of-a-kind Natrium project is being developed through the US Department of Energy’s Advanced Reactor Demonstration Program (ARDP) public-private partnership.

According to the Environmental Impact Statement (EIS), Kemmerer Unit 1 would demonstrate an advanced sodium-cooled reactor, with one 840 MWt pool-type sodium fast reactor connected to a molten salt energy storage system that enables a variable energy supply of up to 500 MWe (net). The storage technology is designed to keep base output steady, ensuring constant reliability and can quickly ramp up when demand peaks: TerraPower says it is the only advanced reactor design with this unique feature.

The Environmental Impact Statement evaluates the environmental impacts of the proposed plant, which would demonstrate the Natrium advanced reactor while ultimately replacing electricity generation capacity following the planned retirement of existing coal-fired facilities. It says: "After weighing the environmental, economic, technical, and other benefits against environmental and other costs, and considering reasonable alternatives, the NRC staff recommends, unless safety issues mandate otherwise, that the NRC issue the requested Construction Permit to [TerraPower subsidiary] USO."

TerraPower President and CEO Chris Levesque said the announcement from the NRC was a "testament" to the team's dedication and rigour in meeting all federal licensing requirements. "The Natrium plant in Wyoming, Kemmerer Unit 1, is now the first advanced reactor technology to successfully complete an environmental impact statement for the NRC, bringing us another step closer to delivering America's next nuclear power plant," he said.

Earlier this year the NRC said it intended to accelerate its schedule to complete the review of TerraPower's construction permit application six months earlier than originally envisaged. The next step will be the completion of the final safety evaluation, which is anticipated by the end of December, the company said.

Construction of the non-nuclear portions of the site began in June 2024.