
The U.S. Nuclear Regulatory Commission (NRC) notified TerraPower that their commissioners voted to award the Natrium plant, Kemmerer Unit 1, with a construction permit on Wednesday, March 4. This is the first commercial-scale, advanced nuclear power plant to ever receive this permit.
TerraPower President and CEO, Chris Levesque, issued a statement on the news.
“Today is a historic day for the United States’ nuclear industry,” he said. “We are beyond proud to receive a positive vote from the Nuclear Regulatory Commissioners to grant us our construction permit for Kemmerer Unit One. Our team has worked relentlessly for over four years with the NRC staff to get to this moment. We had extensive pre-application engagement with the NRC; and we submitted a robust and thorough construction permit application almost two years ago. We have spent thousands of manpower hours working to achieve this momentous accomplishment.”
According to Levesque, construction on the Natrium plant will begin in “[the] coming weeks and [we] look forward to bringing the first Natrium reactor and energy storage system to market in the great state of Wyoming.”
TerraPower was the first developer to submit a construction permit application for a commercial advanced reactor to the NRC in March 2024, it was docketed by the NRC in May 2024. The NRC established an initial 27-month review schedule. In 2025, the review process was streamlined due to TerraPower’s complete application, the company’s responsiveness to questions, the NRC staff’s dedication to the review process, Congressional support with the Nuclear Energy Innovation and Modernization Act and President Trump’s Executive Orders that support nuclear energy. The review was completed in 18 months.
The Natrium technology is the first-mover in the advanced reactor sector and is well positioned to support rapidly increasing energy demand. The Natrium plant design features a 345 MW sodium-cooled fast reactor with a patented molten salt-based energy storage system. The storage technology can boost the system’s output to 500 MW of power when needed as it is designed to keep base output steady, ensuring constant reliability, and can quickly ramp up when demand peaks — it is the only advanced reactor design with this unique feature.
The first Natrium plant is being developed through the U.S. Department of Energy’s Advanced Reactor Demonstration Program (ARDP), a public-private partnership. That project is expected to be completed in 2030 and will be the first utility-scale advanced nuclear power plant in the United States.
The NRC authorized their staff to issue TerraPower’s subsidiary, US SFR Owner, a construction permit for the company’s Kemmerer Power Station Unit 1 commercial nuclear power plant in Kemmerer, Wyoming.
“This is a historic step forward for advanced nuclear energy in the United States and reflects our commitment to delivering timely, predictable decisions grounded in a rigorous and independent safety review,” NRC Chairman Ho Nieh said.
This is the first commercial reactor the NRC has approved for construction in nearly a decade and the first approval for a non-light water reactor in more than 40 years.
U.S. Senator John Barrasso (R-Wyo.) applauded the Nuclear Regulatory Commission (NRC) for approving the construction permit for TerraPower’s groundbreaking nuclear reactor facility in Kemmerer, Wyoming. This permit allows TerraPower to start building the advanced, sodium-cooled nuclear reactor on a site near an existing coal-fired power plant in Kemmerer.
“Wyoming is the energy capital of America. We are also the number one producer of uranium in the country,” said Senator Barrasso. “That’s why Wyoming is the right place to build modern nuclear energy infrastructure that provides safe, affordable, and reliable energy. This groundbreaking project is another way to help diversify Wyoming’s already strong energy economy.”





