TerraPower

AActiveFounded 2008🇺🇸Bellevue, Washington

CEO

Chris Levesque

Data verified as of Jul 12, 2026

Summary

TerraPower is a nuclear innovation company founded by Bill Gates and focused primarily on the Natrium sodium fast reactor with integrated molten-salt energy storage. In March 2026 the NRC issued Kemmerer Unit 1 the first construction permit for a commercial-scale advanced nuclear plant in the U.S., and on April 23, 2026 TerraPower and contractor Bechtel officially began plant construction in Wyoming, a build expected to mobilize roughly 1,600 workers. In January 2026 TerraPower signed a landmark agreement with Meta to develop up to eight Natrium plants in the U.S., marking a shift from a single demonstration toward a commercial fleet. The company remains pre-revenue, but Natrium has moved from development into full project execution under DOE's ARDP cost-share program.

Company OverviewRead the long-form profile of TerraPower

Main Products

Natrium

In Development

Sodium-cooled fast reactor with integrated molten salt energy storage, enabling flexible output from 345 MWe to 500 MWe peak.

Demonstration plant (Kemmerer Unit 1) under construction in Wyoming — NRC construction permit issued March 2026, construction started April 2026 with contractor Bechtel, with construction completion targeted by ~February 2031 and commercial operation in the early 2030s. A January 2026 Meta agreement covers up to eight additional Natrium plants, and May 2026 agreements with HD Hyundai and HDEC support component manufacturing and EPC delivery for the commercial fleet.

Electrical Output345 MWe (baseload)

Peak Output500 MWe (with storage)

Reactor TypeSodium-cooled fast reactor (HALEU-fueled)

Energy StorageMolten salt (boosts 345→500 MWe for 5.5+ hours)

Demo Plant LocationKemmerer, Wyoming

Target OperationEarly 2030s (construction complete ~Feb 2031)

Molten Salt Energy Storage

In Development

Integrated thermal energy storage system using molten salt to decouple reactor output from grid delivery, enabling peak power output.

Part of the Natrium system — allows flexible power dispatch to complement intermittent renewables.

Storage TypeMolten nitrate salt

Peak Boost345 MWe → 500 MWe

Duration5.5+ hours at peak

PurposeGrid flexibility / renewable complement

What's Next

Execute Kemmerer Unit 1 construction

With construction underway alongside contractor Bechtel and a workforce mobilizing toward ~1,600, TerraPower's central execution challenge is building Kemmerer Unit 1 on schedule; project owner US SFR Owner LLC has told the NRC it expects to complete construction by February 2031, ahead of an operating-license phase and commercial operation in the early 2030s.

Construction complete ~Feb 2031

First sodium reactor criticality

Targeting initial criticality of the Natrium reactor at the Kemmerer plant, marking the first sodium-cooled fast reactor to operate in the U.S. in decades, after construction completion targeted around February 2031.

Early 2030s

Secure HALEU fuel supply

Natrium operation depends on securing adequate HALEU fuel through TerraPower's partnerships with Centrus, Framatome, GNF-A, and ASP Isotopes, plus completing supporting fuel-fabrication and sodium test-and-fill infrastructure under the ARDP program.

Late 2020s

Begin commercial Natrium fleet under Meta agreement

Move the January 2026 Meta agreement for up to eight Natrium plants from early development into deployment, with the first commercial units targeted to come online as early as 2032. TerraPower's May 2026 commercialization agreements with HD Hyundai and HDEC are intended to build out the component-manufacturing and EPC supply chain needed to deliver the fleet at scale.

2032

Recent News

View all →

Jun 17

TerraPower enters UK regulatory review, opens UK subsidiary

TerraPower said on June 16 that its 345-MWe Natrium sodium-cooled fast reactor has formally entered the UK's Generic Design Assessment, the Office for Nuclear Regulation-led licensing process that vets a reactor's safety, security and environmental case independent of a site. The Bill Gates-founded company also launched a UK subsidiary, TerraPower UK Ltd, to pursue British deployment. The move follows the April 23 start of construction on TerraPower's flagship Kemmerer Unit 1 in Wyoming, the first U.S. utility-scale advanced reactor build, which is targeted for completion around 2030.

Operations & Revenue

StatusPre-revenue

Pre-revenue, but no longer just at the concept stage. Kemmerer Unit 1 received an NRC construction permit in March 2026 and entered full construction with contractor Bechtel on April 23, 2026, mobilizing roughly 1,600 workers at peak; project owner US SFR Owner LLC has told the NRC it expects to complete construction by February 2031 before seeking an operating license, with commercial operation in the early 2030s. A January 2026 agreement with Meta for up to eight Natrium plants and May 2026 commercialization agreements with HD Hyundai and HDEC (component manufacturing and EPC delivery) position TerraPower among the most commercially advanced U.S. advanced-reactor developers.

Pipeline & Contracts

DOE Cost-Share Funding

$2B+ from DOE's Advanced Reactor Demonstration Program to build the Natrium demonstration plant.

Private Investment & Partnerships

Significant investment from Bill Gates, SK Group, and venture partners funding reactor development and demonstration.

Commercial Reactor Deployment (Meta Agreement)

January 2026 agreement with Meta to develop up to eight Natrium plants (up to 2.8 GW baseload, 4 GW peak with storage); Meta funds early development of two units and holds rights to six more — TerraPower's path to commercial revenue beyond the Kemmerer demonstration.

Key Metrics

Employees

~1,000

Est. Annual Revenue

Pre-revenue

DOE ARDP Federal Cost Share

Up to $2B (50/50 cost share)

Natrium Output

345 MWe (500 MWe peak)

Kemmerer Unit 1 Status

Under construction (started Apr. 23, 2026); completion targeted ~Feb 2031

Commercial Fleet (Meta Agreement)

Up to 8 Natrium plants

Construction Workforce

~1,600 workers (peak)

Timeline

2026Meta agreement for up to eight Natrium plants

In January 2026 TerraPower signs a landmark agreement with Meta to develop up to eight Natrium reactor-and-storage plants in the U.S. — up to 2.8 GW of baseload power, boostable to 4 GW with the molten-salt storage. Meta funds early development of two units and holds rights to six more, with first units targeted as early as 2032.

2026NRC permit issued and full Natrium construction begins

The NRC issues the first construction permit for a commercial-scale advanced nuclear plant in the U.S. on March 4, 2026, and TerraPower together with contractor Bechtel officially begins construction of Kemmerer Unit 1 on April 23, 2026, a build expected to mobilize roughly 1,600 workers.

2026Korean commercialization agreements with HD Hyundai and HDEC

On May 20, 2026 TerraPower signs a set of Natrium commercialization agreements with HD Hyundai and Hyundai Engineering & Construction (HDEC): a supply framework agreement naming HD Hyundai Heavy Industries a preferred manufacturer for components of the Natrium Reactor Enclosure System, and a tripartite strategic agreement/MOU to collaborate on design, manufacturing, supply chain, construction, commercialization, and delivery of a fleet of Natrium reactor-and-storage plants. HD Hyundai had already invested $30M in TerraPower in 2022.

2026Natrium enters UK Generic Design Assessment

On June 16, 2026 TerraPower's Natrium reactor formally enters the UK's Generic Design Assessment — the Office for Nuclear Regulation-led licensing process that evaluates a reactor's safety, security and environmental case independent of a specific site — and the company launches a UK subsidiary, TerraPower UK Ltd, to pursue British deployment. It is TerraPower's first regulatory step toward building Natrium plants in the UK.

2024Site work and project preparation advance

TerraPower advances early project work in Kemmerer ahead of receiving the NRC construction permit for the first Natrium plant.

2022Kemmerer site selected

Selects Kemmerer, Wyoming (former coal town) as site for first Natrium demonstration plant.

2020DOE ARDP award

Receives $2B+ cost-share award under DOE's Advanced Reactor Demonstration Program.

2019Natrium design unveiled

Pivots to the Natrium sodium-cooled fast reactor with integrated molten salt storage.

2015China partnership

Signs agreement with China National Nuclear Corporation (CNNC) for TWR development.

2010Traveling wave reactor concept

Develops the traveling wave reactor (TWR) design that can run on depleted uranium.

2008Founded

Bill Gates and a group of technologists found TerraPower to develop advanced nuclear energy.

Funding

Cumulative disclosed raise · dated rounds

Round	Date	Amount	Investors
Founder & early investors	2008–2018	$1B+	Bill Gates, Khosla Ventures, venture partners
DOE ARDP cost-share	2020	$2B+ (government share)	U.S. Department of Energy
Series B	2022	$750M (incl. SK Group/Gates $250M lead)	SK Group, Bill Gates, HG Power, others