TRISO-X Completes Vertical Construction of TX-1 Fuel Fabrication Facility

• Completion of vertical construction marks major milestone for first-in-the-nation commercial scale advanced nuclear fuel fabrication facility
• Project advances into interior buildout, fuel fabrication equipment installation and construction of supporting facilities

OAK RIDGE, Tenn. – September 24, 2026 – TRISO-X, LLC (“TRISO-X” or the “Company”), a wholly-owned subsidiary of X-Energy, Inc. (Nasdaq: XE) (“X-energy”), today announced the completion of vertical construction at TX-1, its first-in-the-nation advanced nuclear fuel fabrication facility in Oak Ridge, Tennessee. The milestone completes the primary building structure of the 214,000-square-foot facility and enables the project to advance fully into its next phase of construction, including interior buildout, installation of fuel fabrication equipment and continued construction of supporting facilities.

“Completing vertical construction is a major milestone for TX-1 and another tangible demonstration of the progress our team is making in Oak Ridge,” said Joel Duling, President of TRISO-X. “We are moving from constructing the core and shell of the facility to building out the interior utilities, installing manufacturing equipment, and constructing key support capabilities. Every milestone brings us closer to establishing a new domestic source of advanced nuclear fuel and supporting the deployment of the next generation of American nuclear reactors.”

Clark Construction Group continues to serve as construction contractor, leading interior buildout of the facility’s process equipment and administration building, installation of fuel fabrication equipment, and construction of an adjacent graphite matrix powder building. Last month, TRISO-X announced that it had initiated elements of this next phase as vertical construction neared completion. With the structure now complete, construction activity shifts to the systems, equipment and infrastructure required to prepare TX-1 for commercial operations.

Once operational, TX-1 is expected to produce approximately 700,000 TRISO-X fuel pebbles annually, equivalent to 5 metric tons of uranium (“MTU”), with capacity to provide fuel for up to 11 Xe-100 reactors. The U.S. Nuclear Regulatory Commission (“NRC”) granted TRISO-X a 40-year Special Nuclear Material License for the facility earlier this year, the first-ever NRC Category 2 fuel fabrication license issued for the processing of high-assay low-enriched uranium. TX-1 is expected to be the first new commercial-scale advanced U.S. nuclear fuel fabrication facility built in more than 50 years.

The completion of vertical construction builds on a period of sustained progress across TRISO-X’s Oak Ridge operations. In recent months, the Company expanded its nuclear fuel campus by approximately 70 acres, extended its cooperative research and development relationship with Oak Ridge National Laboratory, initiated construction of TX-L, a dedicated research and development facility, and received economic development support from the State of Tennessee for continued expansion of its advanced nuclear fuel campus.

TX-1 is being developed initially to support X-energy’s proposed deployment of its Xe-100 advanced small modular reactor at Dow Inc.’s UCC Seadrift Operations manufacturing site in Texas through the U.S. Department of Energy’s Advanced Reactor Demonstration Program. X-energy is also advancing additional Xe-100 projects in partnership with Energy Northwest, Amazon, and Centrica as demand grows for secure, reliable, and scalable nuclear energy.

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About X-energy

X-energy is a leading designer of advanced small modular nuclear reactors (“SMR”) and fuel technology developed to establish a new standard in clean, safe, reliable energy. X-energy’s intrinsically safe Xe-100 high-temperature gas-cooled reactor and TRISO-X particle fuel expand applications for nuclear technology, with commercial projects across grid, industrial, and AI. Together, X-energy’s technology drives enhanced safety, lower cost, faster construction timelines, and scalable deployment when compared with other SMRs and conventional nuclear. For more information, visit X-energy.com or connect with us on X or LinkedIn.

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 and its subsidiary TRISO-X intend 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,” “will,” “seek,” 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 TX-1 construction; TX-1’s expected capacity; the expected benefits of the Company’s Oak Ridge campus; and the anticipated development and completion of X-energy’s ongoing reactor projects.

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: delays, cost increases, or setbacks in the construction and interior buildout, licensing, or scaling of TX-1 and the Company’s fuel fabrication campus; changes, delays, or inability to obtain and maintain licenses or governmental approvals; supply chain and supplier constraints; and first-of-a-kind risks and the Company’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 Form 10-Q 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.