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Dow, X-energy Proposed SMR Project Receives Historic Construction Permit for Nuclear-Powered Industrial Site

Milestones
  • Construction Permit issuance completes NRC Safety and Environmental reviews
  • Proposed four-unit Xe-100 plant at Dow’s Seadrift site would be the first advanced nuclear facility to power an industrial site in the United States
  • Historic milestone achieved under U.S. Department of Energy’s Advanced Reactor Demonstration Program

ROCKVILLE, Md. – November 9, 2026 – X-Energy, Inc. (Nasdaq: XE) (“X-energy” or “the Company”), a leading developer of advanced nuclear reactors and fuel technology, and Dow (NYSE: DOW) through its wholly-owned subsidiary Long Mott Energy, LLC (“Dow”) today announced that the U.S. Nuclear Regulatory Commission (“NRC”) has approved the Construction Permit Application (“CPA”) for the proposed construction of four Xe-100 advanced small modular reactors at Dow’s UCC Seadrift Operations site in Texas. The CPA approval makes Long Mott Generating Station the first advanced nuclear facility approved for an industrial site in the United States, a historic milestone achieved under the U.S. Department of Energy’s Advanced Reactor Demonstration Program (“ARDP”).

Approval of the construction permit enables X-energy and Dow (the “Companies”) to continue advancing the proposed project toward construction readiness, finalizing and standardizing the Xe-100 design, maturing the supply chain for long-lead components and materials, and developing an Operating License application for submission to the NRC. This supports Dow’s consideration of the proposed project’s next phases, ensuring the design, equipment, and materials are in place before allocating major capital for full-scale construction, consistent with Dow’s proven global project management practices. For a first-of-a-kind project, this reduces schedule and cost risk once work begins on site, and is aligned to the Company’s established timeline of first delivery in the early 2030s.

Issuance marks the first NRC CPA approval of a high-temperature gas-cooled reactor in nearly 60 years, the first-ever pebble-bed HTGR approval and the first-ever for a nuclear industrial deployment. The NRC’s review found that the Xe-100 design can be safely sited and constructed within an operating industrial site. The proposed plant is intended to provide both electricity and high-temperature steam to Dow’s site, replacing existing energy and steam assets near their end-of-life. The four first-of-a-kind Xe-100s deployed at Seadrift are expected to provide clean industrial power to the site for 60 years.

The NRC completed its review in alignment with its established schedule, evaluating the safety and environmental impacts of the proposed Xe-100 facility against the global benchmark for safe, responsible operation of nuclear technology. Across both parts of the review, the intrinsic safety characteristics of the design and extensive pre-application engagement supported an efficient, thorough, independent review that met or exceeded the NRC’s high standard, supported by decades of U.S. Department of Energy research on HTGRs and TRISO fuel, and strengthened by the passage of the bipartisan ADVANCE Act in 2024. CPA approval by the NRC builds on this body of work, and positions future Xe-100 applications for enhanced efficiency in commercial nuclear licensing by incorporating learnings from Long Mott’s review.

X-energy’s Xe-100 is an 80 MWe/200 MWt high-temperature gas-cooled reactor designed to ensure safety through the passive physics of its advanced TRISO-X coated particle fuel, as well as traditional defense-in-depth systems. TRISO fuel encompasses, in one component, many barriers to the release of radionuclides, and has been described by the DOE as, “the most robust nuclear fuel on earth.” This safety profile is expected to support a 400-meter emergency planning zone, compared to 10 miles for conventional light-water reactors, enabling new generation to be safely sited closer to the point of need.

Since 2018 and 2023, X-energy and Dow, respectively, have worked with the NRC through extensive pre-application engagement to demonstrate the safety profile of the Xe-100 and its TRISO-X fuel, directly cited by the NRC as a contributor to the application’s efficient review. The Companies intend to carry this same discipline and rigor into the next phase of the project, ensuring construction and commercial readiness before major site work begins to reduce cost and schedule risk. Dow is expected to consider a preliminary investment decision in 2027. Full-scale nuclear construction would begin following Dow’s final investment decision, advancing a shared, generational vision for next-generation nuclear technology to commercial scale under ARDP.

Quotes

J. Clay Sell, CEO of X-energy said, “This is an important day. Getting the construction permit earlier than expected is reflective of the thorough and efficient work of the NRC, the reforms that have been put in place by the Congress over the last six years, and the phenomenal work of the X-energy and Dow teams.  This milestone is further validation of the XE regulatory approach that can be replicated across our growing commercial pipeline, giving our customers greater confidence in the regulatory process and a clearer path to deployment.”

“This is another important milestone for the proposed Long Mott Generating Station project and a testament to the thoughtful, thorough and efficient review conducted by the NRC,” said Edward Stones, Business Vice President, Energy & Climate at Dow. “We appreciate the NRC’s commitment to maintaining the highest standards of safety while advancing a clear and predictable regulatory process for advanced nuclear technologies. As we move forward, we will continue to evaluate the project through the lens of competitiveness, execution readiness, and capital affordability before any decision regarding construction is made.”

“Today, the new NRC is issuing America’s first construction permit for a high-temperature gas-cooled reactor in more than half a century,” NRC Chairman Ho K. Nieh said. “We delivered on the 18-month schedule, proving we can do rigorous safety reviews on predictable timelines that move advanced nuclear technology from design to construction.”

“This milestone marks a significant step forward for the Department of Energy’s Advanced Reactor Demonstration Program and our efforts to bring next-generation nuclear technologies to market,” said Principal Deputy Assistant Secretary for Nuclear Energy Mike Goff. “The NRC’s approval demonstrates meaningful progress toward deploying advanced reactors that can deliver reliable power and industrial heat, strengthen American energy leadership and expand the role of nuclear energy in meeting our nation’s growing energy demands.”

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About X-energy
X-energy, Inc. is a leading developer of advanced small modular nuclear reactors and fuel technology designed to establish a new standard in clean, safe, reliable energy. X-energy’s intrinsically safer Xe-100 high-temperature gas reactor and TRISO-X particle fuel expand applications for nuclear technology, with commercial projects underway with Dow, Amazon, and Centrica across grid, industrial, and AI applications. Together, X-energy’s technology drives enhanced safety, lower cost, faster construction timelines, and scalable deployment when compared with other SMRs and conventional nuclear.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, which X-energy intends to be covered by the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Words such as “assume,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “seek,” “will,” the negative of these words, or similar terms may identify forward-looking statements, but their absence does not mean a statement is not forward-looking. These include, but are not limited to, statements regarding the next phase of the proposed Long Mott Generating Station project following approval of the CPA, including advancing toward construction readiness, finalizing the Xe-100 design, maturing the supply chain and submitting an operating license application to the NRC; the expected timing of Dow’s investment decisions; the expected timing related to the project, including commencement of full-scale nuclear construction and delivery; the proposed plant’s expected 60-year operating life; the expected learnings from NRC’s review of the CPA, including statements with respect to efficiencies on future Xe-100 projects; the expected safety profile, features and siting benefits of the Xe-100; the status and timing of X-energy’s commercial projects and X-energy’s commercial pipeline; and X-energy’s vision and strategy.

You should not rely on these forward-looking statements as predictions of future events. Actual results may differ materially due to a number of factors, including, but not limited to: the risk that the NRC’s review of the CPA does not result in more efficient or predictable licensing of future Xe-100 projects; design changes following the construction permit, including in connection with finalizing the Xe-100 design; the failure to obtain, or delays in obtaining, required licenses, permits and regulatory approvals, including an operating license for the Long Mott Generating Station; site suitability and characterization risks; the decision of X-energy’s customers, including Dow, whether to proceed with construction; Dow’s preliminary and final investment decisions, which will depend on, among other factors, execution readiness and affordability; the ability of X-energy and its customers to obtain project financing and achieve acceptable project economics; delays, cost increases or setbacks in the licensing, construction or deployment of X-energy’s projects, including the risk that X-energy projects do not meet their expected timelines; supply chain and supplier constraints; the risk that X-energy’s commercial pipeline does not convert into additional definitive agreements or completed projects; changes in government policy, funding or support for advanced nuclear energy, including under the ARDP; public or stakeholder opposition; and first-of-a-kind risks and X-energy’s limited operating experience at intended scale, including latent design or operational issues. More information about potential risks is detailed under “Risk Factors” in X-energy’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2026 filed with the Securities and Exchange Commission (the “SEC”), and in subsequent SEC filings, available on X-energy’s Investor Relations website at https://investors.x-energy.com/ and on the SEC website at www.sec.gov. Any forward-looking statements herein are based on assumptions believed reasonable as of, and speak only as of, the date of this press release. Except as required by law, X-energy undertakes no obligation to update these statements as a result of new information or future events.

Contact

Jakub Lis, Corporate Communications
[email protected]
+1 240-642-3420

Patricia Gil, Investor Relations
[email protected]
+1 301.558.3040

Frequently Asked Questions

An NRC Construction Permit grants federal approval for a commercial nuclear facility to begin construction in accordance with the design approved in the permit. Long Mott Energy, LLC, a wholly owned subsidiary of Dow, is the permit applicant and recipient. The permit follows completion of the NRC’s safety and environmental reviews under its 10 CFR Part 50 licensing process. It is not final approval, and it does not authorize operation. Once fully built, and before loading fuel and startup operations, a commercial nuclear facility must receive an Operating License from the NRC.

This is the first NRC CPA approval of a high-temperature gas-cooled reactor in nearly 60 years, and advances what is expected to be the first grid-scale advanced nuclear reactor project at a U.S. industrial facility in history. The NRC has found that an advanced reactor can be safely sited and constructed within an operating industrial site, providing validation of our design and safety case that helps open nuclear energy to industries beyond conventional electric power. The proposed four-unit plant would supply both electricity and high-temperature steam to Dow’s UCC Seadrift Operations site.

Full-scale construction is expected to begin following a final investment decision by Dow’s Board of Directors. Dow and X-energy continue to move the proposed project through its defined milestones, including continued engineering and design finalization to ensure commercial and technical readiness. Dow is expected to consider a preliminary investment decision in 2027. Full-scale nuclear construction would begin following Dow’s final investment decision, advancing a shared, generational vision for next-generation nuclear technology to commercial scale under ARDP.

Dow is one of the world’s most experienced developers of large industrial facilities, and advances every major project through a structured, phased decision process designed to manage capital and development risk over a project’s lifecycle. For a first-of-a-kind nuclear facility, applying this discipline helps to ensure maximum design, engineering and supply chain maturity before construction begins, helping to minimize delays and reworks. This deliberate, disciplined approach reduces overall schedule and cost risk, and is aligned to the long-established timeline of first delivery in the early 2030s.

Dow submitted the CPA in March 2025, with X-energy serving as technical and licensing lead. The NRC docketed the application and set an 18-month review schedule in June 2025, and completed its review in alignment slightly ahead of that schedule. It was a comprehensive, independent review of the proposed facility, site characteristics, construction plans, environmental considerations and safety-related information submitted by Dow and X-energy.
It was an efficient, thorough, independent review that met or exceeded the NRC’s high standard. NRC approval carries weight with customers, investors and regulators around the world, and that credibility is part of what makes the Xe-100 attractive to potential customers both in the U.S. and abroad.

X-energy’s regulatory strategy is built on a simple premise: do the foundational work today to help ensure safe, scalable deployment tomorrow. Long Mott Energy submitted the Construction Permit Application in March 2025, with X-energy’s support as technical and licensing lead. When the NRC set its review schedule, it cited the completeness and quality of the application and the effectiveness of pre-application engagement.
X-energy began pre-application engagement with the NRC in 2018, and Dow joined in 2023. This has resulted in more than a dozen approved topical reports that help to resolve complex safety questions before formal licensing begins. Each approved report becomes a referenceable regulatory asset; one that future projects can cite without re-justifying the underlying analysis. These form the technical foundation of the Xe-100 safety case, representing years of iterative engagement, rigorous analysis, and regulatory validation; evidence that X-energy’s technology meets the gold standard of nuclear safety while enabling industrial decarbonization, grid reliability, and energy independence.

The Advanced Reactor Demonstration Program is a U.S. Department of Energy program designed to help drive private sector investment in advanced nuclear energy and establish a commercial market for the technology. DOE selected X‑energy as one of two primary awardees, and X‑energy has been informed its award is intended to be increased to $2.15 billion in total to deliver a first‑of‑a‑kind commercial advanced nuclear plant and TRISO‑X fuel fabrication facility.
The program has provided a clear, disciplined pathway that enables the private sector to lead the nuclear renaissance from first-of-a-kind to full commercial scale. Since the award, the Xe-100 has gone from concept to a commercial pipeline of more than 11 GW, equal to 144 Xe-100 reactors. That includes the Cascade Advanced Energy Facility with Amazon and Energy Northwest, a second Amazon project with AEP, and a partnership with Centrica targeting approximately 6 GW in the United Kingdom.

Commercial licensing of the Xe-100 builds on decades of U.S. Department of Energy research on HTGR and TRISO fuel technology: 

  • The NRC’s technology-inclusive, risk-informed, and performance-based licensing framework used for Long Mott was first developed for DOE’s Next Generation Nuclear Plant program in 2008.
  • TRISO-X fuel is based on TRISO fuel designs pioneered by DOE through the Advanced Gas Reactor Program, which provided both irradiation data and production specifications over 20 years of testing that are central to the fuel’s design today.
  • In April 2025, TRISO-X was allocated an initial tranche of High-Assay Low-Enriched Uranium through DOE’s HALEU Availability Program, which will be used to manufacture fuel for the first core loads at Long Mott.
  • The project itself is supported through DOE’s Advanced Reactor Demonstration Program.

The ADVANCE Act of 2024 is federal legislation that passed with bipartisan support and was signed into law in July 2024 by President Biden. It requires the NRC to modernize licensing of reactors and fuels, while maintaining the NRC’s core safety and security mission. Among its provisions, the Act supports recruiting and retaining the NRC workforce, strengthens the regulatory framework for advanced reactors, and requires initiatives that support efficient, timely and predictable reviews of license applications.

Long Mott’s application can serve as a reference plant for every successive Xe-100 license application. X-energy’s 14 NRC-approved topical reports apply to the Xe-100 design generically, not just to Long Mott, so future applications can cite these approved methodologies without re-demonstrating the underlying technical basis. While each application will be reviewed individually, this positions future reviews to focus on site-specific factors and better pursue opportunities for enhanced efficiency.
Long Mott’s licensing record also supports X-energy’s plans in the United Kingdom, where the Xe100 is now in Generic Design Assessment. X-energy expects to transfer NRC-reviewed design documentation, including its approved topical reports, into the Office for Nuclear Regulation’s review, building on the technical basis already established in the United States.