Oak Ridge’s growing role in the next generation of nuclear energy took another step forward this week.

TRISO-X announced Thursday that it has completed vertical construction on TX-1, its new advanced nuclear fuel fabrication facility in Oak Ridge. The milestone means the primary structure of the 214,000-square-foot building is now complete, allowing construction to shift toward interior buildout, fuel-manufacturing equipment and supporting facilities.

The facility is being built to manufacture TRISO fuel, a type of advanced nuclear fuel designed for high-temperature reactors. Once operational, TX-1 is expected to produce about 700,000 fuel pebbles per year, enough to support as many as 11 of X-energy’s Xe-100 small modular reactors.

The project has been moving quickly this year. TRISO-X recently expanded its Oak Ridge campus by about 70 acres, bringing the total footprint to roughly 180 acres, and the company has also started work on a dedicated research and development facility.

The state has backed that expansion with an $11 million economic-development grant, intended to help support the existing TX-1 project, a possible second commercial fuel facility and additional research capacity.

TX-1 also crossed a major regulatory threshold earlier this year when the Nuclear Regulatory Commission granted TRISO-X a 40-year license to commercially fabricate fuel using high-assay low-enriched uranium. X-energy says the project is expected to become the first new commercial-scale advanced nuclear fuel fabrication facility built in the United States in more than 50 years.

For Oak Ridge, the significance goes beyond one construction project. The company’s expansion, its ongoing partnership with Oak Ridge National Laboratory and new state investment are all adding to the city’s long-standing identity as one of the country’s most important centers for nuclear research and technology.