Last Energy Clears Key Safety Hurdle for Texas Nuclear Pilot

The U.S. Department of Energy has approved Last Energy's final safety analysis for its pilot reactor at Texas A&M-RELLIS, moving the Texas project into the final readiness review before startup authorization. The milestone advances the company's plans to demonstrate its microreactor technology ahead of commercial deployment.

What did DOE approve?

Last Energy announced that the U.S. Department of Energy (DOE) approved the Documented Safety Analysis (DSA) for its pilot reactor at Texas A&M-RELLIS in Brazos County.

The DSA is the final and most comprehensive safety analysis in the DOE authorization process. It details how the reactor and facility will be operated safely, building on the Preliminary Documented Safety Analysis approved in May 2026.

With the approval secured, the project moves into DOE's readiness review, the final step before the department can authorize setup activities, including initial nuclear criticality and reactor operations.

The RELLIS project is intended to demonstrate the company's reactor technology and support its broader commercial deployment strategy.

Last Energy says the pilot uses the same full-scale reactor core as its commercial design and relies on low-enriched uranium (LEU) fuel. The company argues that using established commercial fuel supplies could support future fleet-scale deployment.

Its commercial PWR-20 is a 20-megawatt-electric micro modular nuclear plant designed for factory fabrication, road transport, and rapid on-site assembly. The company is targeting industrial facilities, data centers, and other customers that require reliable, around-the-clock electricity.

The RELLIS pilot is a smaller PWR-5 demonstration project intended to test the technology before commercial deployment. Texas A&M has described the project as a platform for demonstrating nuclear technology and advancing energy research.

What comes next?

Last Energy was selected in August 2025 for DOE's Reactor Pilot Program, established to accelerate reactor demonstrations through the department's authorization process. The program followed President Donald Trump's executive order on reforming nuclear reactor testing at DOE.

The readiness review will determine whether the project meets the requirements for startup authorization. The next major milestone is permission to begin reactor operations and demonstrate the technology under the approved testing framework.