TerraPower received construction permit from Nuclear Regulatory Commission for its Natrium sodium-cooled reactor in Kemmerer, Wyoming marking first commercial advanced reactor approval in United States. The 345-megawatt reactor backed by Bill Gates represents first NRC construction permit issued in nearly a decade. Construction began in April 2026 with completion targeted for 2030.
The reactor design uses molten sodium instead of water as coolant marking first commercial non-light-water reactor approved by NRC in more than 40 years. TerraPower CEO Chris Levesque stated the company spent thousands of manpower hours working to achieve this momentous accomplishment. The plant combines sodium-cooled reactor with molten salt-based energy storage system boosting power output to 500 megawatts during peak demand.
Virtually all of the world’s commercial nuclear reactors use water to control reactions and transfer heat to drive turbines. The Natrium design operates at atmospheric pressure using natural convection of sodium coolant to help cool the reactor during failures. The last commercial non-light-water reactor operating in United States was Fort St. Vrain nuclear plant in northern Colorado shut down in 1989.
Bill Gates founded TerraPower in 2015 with backing from NVIDIA and SK Group which invested $250 million in 2022. The startup raised total $1.7 billion including $650 million round that closed in June according to PitchBook. The project receives up to $2 billion in federal funding through Department of Energy’s Advanced Reactor Demonstration Program.
When Bill Gates started learning about nuclear power innovation, “I was skeptical, but also intrigued,” he wrote on his Gates Notes blog in 2019.
Meta announced agreement in January 2026 to fund two Natrium reactors to be built by 2032 and six more by 2035. Gates told reporters in October he thinks nuclear power will be gigantic contributor to powering data centers. The reactor will run on high-assay low-enriched uranium with TerraPower lining up domestic and South African sources.
