TerraPower Starts Construction of First U.S. Utility-Scale Advanced Nuclear Power Plant

TerraPower has officially begun construction of its first Natrium plant, Kemmerer Unit 1 in Wyoming. The U.S. Nuclear Regulatory Commission (NRC) issued the construction permit on March 4, 2026, making the first advanced commercial reactor approved for construction in the U.S. in decades and the first non-light-water reactor in more than 40 years.

TerraPower President and CEO Chris Levesque described the project as a “blueprint” for deploying future Natrium plants across the United States and internationally. In January 2026, TerraPower and Meta also announced an agreement supporting the potential deployment of up to eight future Natrium reactors.

Natrium Reactor Design and Energy Storage Capability

The Natrium reactor, integrated with a molten salt storage system, can generate electricity at 345-500 MW for over five hours on demand. This flexible design addresses one of the energy sector’s biggest challenges: delivering reliable, carbon-free electricity when renewable energy sources such as wind and solar are unavailable or operating at lower output.

If successful, the Kemmerer project could establish Wyoming as the starting point for utility-scale advanced nuclear power in the United States while also creating a commercial and construction model for future Natrium deployments.

Project Timeline and Regulatory Progress

Although construction has officially started, one major regulatory milestone remains before the plant can begin commercial operations. TerraPower’s subsidiary, U.S. SFR Owner LLC, has submitted a separate operating license application to the NRC, which must be approved before the facility can generate and sell electricity commercially.

The project is supported by federal funding through the Advanced Reactor Demonstration Program (ARDP), which was created to accelerate the development of advanced nuclear technologies in the United States.

TerraPower originally broke ground at the Kemmerer site in June 2024 and began construction activities on non-nuclear infrastructure and support facilities. Once completed, the facility is expected to become both Wyoming’s first commercial nuclear power plant and the country’s first utility-scale advanced nuclear reactor.

Strategic Partnerships Supporting the Project

Several major partnerships are helping strengthen the foundation of the Kemmerer project.

• Bechtel is serving as the engineering, procurement, and construction contractor. The company is working with TerraPower to apply advanced project management systems, digital construction tools, and standardized execution methods designed to improve efficiency and reduce construction risk for future Natrium plants.
• Meta’s agreement with TerraPower to support up to eight future Natrium projects represents one of the largest publicly disclosed corporate partnerships for advanced nuclear energy in the United States. The agreement reflects rising demand for reliable, carbon-free electricity from AI infrastructure and hyperscale data centers.
• Rocky Mountain Power, the project’s utility partner and future power offtaker, has also emphasized the importance of dependable baseload power for long-term grid reliability. Utility support is considered critical for the successful integration of advanced nuclear energy into regional electricity systems.

Why the Kemmerer Project Matters

The Kemmerer project represents more than the construction of a single nuclear plant. It demonstrates a potential pathway to bring advanced reactor concepts from licensing and financing to full-scale commercial deployment.

The combination of federal investment, private-sector partnerships, and a more modernized regulatory framework has created conditions that previous advanced nuclear projects in the United States often lacked. As a result, the industry will closely monitor whether Kemmerer Unit 1 can meet its targeted commercial operation timeline in 2031.