The Natrium reactor project is a planned next-generation nuclear power facility proposed for development in Wyoming. The plant is intended to replace capacity at a retiring coal-fired power plant and support electricity generation using advanced reactor technology.

The facility will be developed by TerraPower in partnership with PacifiCorp, which is owned by Berkshire Hathaway. It is associated with Bill Gates, who is a co-founder of TerraPower.

According to project details, the plant will incorporate a sodium-cooled reactor design combined with a molten salt energy storage system. The development is planned to be located at the site of a coal-fired power facility that is scheduled for retirement.

The project, referred to as the Natrium reactor, is intended to demonstrate advanced nuclear technology and support electricity generation as part of broader energy transition efforts.

Current status:

As of 2026, TerraPower’s Natrium reactor project is moving forward with construction permit approval expected by early 2025. This follows the completion of its final environmental impact statement (EIS) in October 2025. The 345 MWe sodium-cooled fast reactor, paired with molten salt energy storage, is aiming to bring the first commercial, utility-scale advanced reactor online in Wyoming by 2031.

Other Projects

Nuclear power is becoming fundamental in the US energy sector with projects other than the Natrium reactor project in Wyoming advancing. Some include the Centrus Energy uranium enrichment plant. The plant is making major expansion advancements as it recently selected Geiger Brothers for a $900 million expansion project.

Both firms signed a Construction Contract that caps aggregate payments at $900 million through January 30, 2031. On the other hand, the scope of implementation by the Geiger Brothers in the expansion includes various aspects.

The firm is mandated to refurbish existing facilities, install equipment and build new infrastructure. Furthermore, they are to do this under a time-and-material structure with agreed labor and markup rates supplemented by future task releases. Fluor Corporation also continues as Engineering, Procurement, and Construction (EPC) contractor.

Also Read: Georgia Nuclear plant reaches milestone in construction

Outlook on the Natrium Reactor Project in Wyoming

The state of Wyoming is the top uranium-mining state. The reactor would use uranium from mines on-site that extract the heavy metal from networks of water wells on the high plains, according to officials.

The 345 MW plant, if all goes as planned, would be capable of powering around 250,000 and would produce hydrogen, which can power trucks and other vehicles with fuel cells. Several coal-fired power plant closures are planned in the coming years, including some in Wyoming, which is the top coal-mining state. It also includes a nuclear plant with hundreds of well-playing jobs, sending power over transmission lines already in place, could possibly offset the economic blow of a coal plant retirement.

“Wyoming has been a leader in energy for over a century and we hope our investment in Natrium will help Wyoming to stay in the lead for many decades to come,” said Mark Gordon, Wyoming’s Governor, “We think Natrium will be a game-changer for the energy industry.” “The future of nuclear energy is here,” said Jennifer Granholm, the US Energy Secretary. “It’s got a simpler design that will hopefully result in faster construction at a lower cost. It’s going to create a smaller footprint. It’s going to be equipped with next-generation safety measures.”

Factsheet

Project Name: Natrium Reactor
Location: Wyoming
Estimated Investment Value: Not publicly disclosed (multi-billion-dollar advanced nuclear project)
Project Type: Advanced nuclear power plant (sodium-cooled fast reactor)

Timeline
2025: Expected construction permit approval
2025: Final Environmental Impact Statement (completed)
2026: Project progressing toward construction phase
2031: Target commercial operation

Site & Scale
Capacity: ~345 MWe
Power Supply: ~250,000 homes (estimated)
Site: Former coal-fired power plant location
Technology: Sodium-cooled fast reactor + molten salt energy storage

Project Teams
Developer: TerraPower
Utility Partner: PacifiCorp
Parent Company: Berkshire Hathaway
Key Figure: Bill Gates

Infrastructure Scope
Advanced sodium-cooled nuclear reactor system
Molten salt energy storage for flexible power output
Grid integration using existing coal plant transmission
Potential hydrogen production capability

Strategic Objectives
Demonstrate next-generation nuclear technology
Replace retiring coal-fired power capacity
Support clean and reliable baseload energy
Advance U.S. energy transition and grid stability

Challenges
Regulatory approvals and permitting timelines
First-of-a-kind technology deployment risks
High capital and construction complexity

Current Status
Environmental review completed
Permit approval expected
Project advancing toward construction phase
Targeting first commercial advanced reactor deployment by 2031