NRC Approves X-energy’s Four Small Modular Reactors at Dow’s Texas Plant, a First for an Industrial Site

The U.S. Nuclear Regulatory Commission on Monday, Nov. 9, approved a construction permit for four X-energy Xe-100 small modular reactors at a Dow chemical plant in Seadrift, Texas.^[1] It is the first U.S. construction permit for a high-temperature gas-cooled reactor in nearly 60 years.^[2]

Related: Fervo’s Geothermal Backlog Jumps to $11.9 Billion After Google Signs for 396 Megawatts.

What the permit covers

The plant is called the Long Mott Generating Station.^[2] Dow is developing it through its subsidiary Long Mott Energy, in partnership with X-energy, under the Department of Energy’s Advanced Reactor Demonstration Program.^[1]

The companies said it is the first advanced nuclear facility approved for an industrial site in the United States.^[1] The plant would supply both electricity and high-temperature steam to Dow’s Seadrift site.^[1] It would replace energy and steam equipment there that is near the end of its life.^[1]

The permit allows the plant to be built but not operated.^[2] A separate operating license is required before the reactors can be fueled.^[2] The NRC released its final safety evaluation report for the application on Oct. 30.^[2]

The approval also marked several NRC firsts.^[2] They include its first approval of a multimodule advanced reactor facility and its first approval of a reactor with a pebble-bed core.^[2]

“We delivered on the 18-month schedule,” NRC Chairman Ho K. Nieh said.^[1]

How the reactor works

The Xe-100 is an 80-megawatt-electric, 200-megawatt-thermal reactor cooled by helium gas.^[1] It uses TRISO-X coated particle fuel, in which each fuel particle has its own coating that contains fission products.^[2]

The companies expect that design to support an emergency planning zone of 400 meters.^[1] Conventional light-water reactors use a 10-mile zone.^[1] The four reactors are expected to power the site for 60 years.^[1]

Construction is not yet decided

Dow has not made a final decision to build the plant.^[2] The company is expected to consider a preliminary investment decision in 2027.^[1] Full-scale nuclear construction would begin only after a final investment decision.^[1]

“We will continue to evaluate the project through the lens of competitiveness, execution readiness, and capital affordability,” said Edward Stones, business vice president for energy and climate at Dow.^[1]

No small modular reactor currently operates in the United States.^[3] X-energy says the Dow reactors will not run until the early 2030s.^[3]

Safety critics and investors

The Union of Concerned Scientists questioned X-energy’s safety claims and the speed of the review.^[3] “The NRC only accomplished this feat by pushing consideration of critical safety questions to a later date,” said Edwin Lyman, the group’s director of nuclear power safety.^[3]

X-energy CEO J. Clay Sell said the permit arrived “earlier than expected.”^[1]

Amazon’s Climate Pledge Fund led X-energy’s $500 million Series C-1 round.^[3] Amazon has also committed to buying 5 gigawatts of capacity from the company.^[3] X-energy raised $1 billion in an April initial public offering.^[3] Its shares trade at less than half their offering price.^[3]

For more on the power demands behind the AI build-out, see The Boston Report’s AI news hub, the Science section and Business & Finance.

Sources

1. X-energy: Dow, X-energy Proposed SMR Project Receives Historic Construction Permit for Nuclear-Powered Industrial Site
2. World Nuclear News: US issues landmark construction permit for Texas SMR plant
3. TechCrunch: X-energy gets green light to build its first small modular nuclear reactors

About the reporter: Theo Lin is an AI reporter covering artificial intelligence, technology and science for The Boston Report. This article was produced with AI under our editorial policy. Read our AI and media disclosure.