The U.S. Nuclear Regulatory Commission announced Wednesday that it has awarded TerraPower a construction permit for its Natrium nuclear power plant outside Kemmerer, a key step in bringing the next-generation project to southwestern Wyoming.
The Kemmerer Unit 1 plant is the first commercial nuclear reactor to win such approval in 10 years in the U.S., and it’s the first ever commercial-scale liquid sodium-cooled reactor to be permitted in the nation, according to TerraPower, which was cofounded by Microsoft founder and billionaire Bill Gates.
“Our team has worked relentlessly for over four years with the NRC staff to get to this moment,” the company said in a prepared statement. “We had extensive pre-application engagement with the NRC, and we submitted a robust and thorough construction permit application almost two years ago.”
The NRC also noted the expediency of its 18-month review as meeting a new benchmark for the agency, which has revised its review and oversight processes in anticipation of a wave of new “advanced” reactor designs.
“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 in a prepared statement.
The Trump administration has ordered the agency to continue streamlining its permitting and certification timelines to meet a wave of demand for new nuclear energy technologies. As part of the effort, the agency notified TerraPower last year it was trimming seven months from the environmental review and safety evaluation for the project.
The NRC reviewed Natrium via the Advanced Reactor Demonstration Program, which was instituted during President Donald Trump’s first term.
“This is a massive move for American energy independence,” U.S. Sen. Cynthia Lummis said on a social media post Wednesday. “Wyoming has always powered this nation. Now we’re leading the next generation of nuclear energy technology.”
Natrium project
The Natrium nuclear power plant is designed to generate 345 megawatts of electricity and has an energy storage component to ramp up to 500 megawatts to meet demand peaks, according to the Bellevue, Washington-based company. One megawatt is enough electricity to power about 750 homes. The $4 billion project is backed by $2 billion from the Department of Energy — a commitment made under the first Trump administration.
TerraPower in 2024 began construction on several non-nuclear facilities associated with the project. The Wyoming Industrial Siting Council granted a construction permit in January 2025, greenlighting all non-nuclear portions of the facility.
Before settling on Kemmerer to build its first Natrium facility, the company reviewed several locations in Wyoming, preferring to “co-locate” the project next to a coal-fired power plant so it could tap into existing power infrastructure. TerraPower chose the Kemmerer location for its proximity to the Naughton power plant, which recently shut down its last two coal-burning units to convert them to natural gas.
Next for the Natrium project, the NRC will formally issue the construction permit “in the next week or so.”
“TerraPower anticipates beginning construction on the Natrium plant in the coming weeks,” spokesperson Sarah Young told WyoFile. The company will submit an application to the NRC for an operating license in 2027 or early 2028.
“Today is a historic day for the United States’ nuclear industry,” TerraPower President and CEO Chris Levesque said in a prepared statement. “We are beyond proud to receive a positive vote from the Nuclear Regulatory Commissioners to grant us our construction permit for Kemmerer Unit One.”
Wyoming is selling it’s soul to the likes of Bill Gates.