The U.S. Nuclear Regulatory Commission issued a construction permit on 9 November 2026 for Dow’s proposed Long Mott Generating Station at its UCC Seadrift Operations in Calhoun County, Texas.

The plant would house four Xe‑100 high‑temperature gas‑cooled reactors, each rated at 80 MW electrical and 200 MW thermal output, delivering a combined 320 MW of electricity and 800 MW of process heat.

Designed to replace aging energy and steam assets at Dow’s chemical complex, the reactors would supply both electricity and high‑temperature steam for industrial processes, rather than selling power to the grid.

The permit authorises construction according to the approved design but does not allow fuel loading or commercial operation; a separate operating license will be required before the reactors can generate power.

Dow’s subsidiary Long Mott Energy LLC filed the construction application on 31 March 2025, which the NRC docketed in May 2025 and reviewed under its commercial licensing process, completing safety and environmental assessments by May 2026.

Dow has said the permit does not constitute a final commitment; the company plans a preliminary investment decision in 2027 after evaluating commercial competitiveness, execution readiness and capital affordability.

If approved, construction could start later this decade with the first electricity and steam deliveries targeted for the early 2030s.

The project is part of the U.S. Department of Energy’s Advanced Reactor Demonstration Program, which has provided up to $1.2 billion in cost‑share funding; an additional award of up to $1 billion was announced in August 2026, though total private capital requirements remain undisclosed.

Regulatory scrutiny included a mandatory NRC hearing and a contested proceeding over a financial‑qualification challenge raised by San Antonio Bay Estuarine Waterkeeper, separate from the construction permit decision.