U.S. Department of Energy Approves Last Energy Microreactor Safety Analysis Report: Texas A&M University PWR-5 Demonstration Reactor Enters Final Pre-Operational Review

The U.S. Department of Energy (DOE) has formally approved the Documented Safety Analysis (DSA) submitted by nuclear startup Last Energy for its proposed test microreactor at the Texas A&M-RELLIS campus (Texas A&M-RELLIS). This approval marks the official transition of the microreactor demonstration project into the Operational Readiness Review phase, which is also the final key regulatory step before obtaining authorization for initial criticality and formally commencing operation.

The Documented Safety Analysis is the most central and detailed final safety assessment document in the U.S. Department of Energy's approval framework. Building upon the Preliminary Safety Analysis Document (Preliminary DSA) approved in May 2026, it comprehensively sets forth the technical and administrative defense-in-depth measures to ensure the safe operation of the reactor and plant facilities throughout their entire lifecycle. Last Energy was selected in August 2025 for the U.S. Department of Energy's Reactor Pilot Program (RPP), which was established pursuant to an executive order on DOE reactor testing reform signed by U.S. President Donald · Trump in early 2025, aimed at accelerating ground validation of advanced microreactors through the Department of Energy's proprietary authorization pathway; licensing of commercial-grade nuclear power plants continues to be the responsibility of the U.S. Nuclear Regulatory Commission (NRC).

According to the plan, Last Energy and Texas A&M University jointly announced on October 15, 2025 the deployment of a microreactor validation platform at the RELLIS Applied Research and Advanced Technology Campus in Bryan, Texas. The PWR-5 test reactor planned for construction at the campus will directly adopt a full-scale core design completely identical to that of the commercial PWR-20 unit, thereby achieving seamless technical continuity from the test prototype to the commercial deployment pathway.

On the commercial product front, Last Energy's flagship PWR-20 is a modular micro pressurized water reactor with an electric power output of 20 megawatts (MWe), specifically designed for factory-standardized prefabrication, conventional road transport, on-site plug-and-play assembly, and minimal/unmanned operation, aimed at providing round-the-clock zero-carbon baseload power for heavy industry, data centers, and high-energy-consumption campuses. The design deeply leverages mature pressurized water reactor (PWR) technology and the existing standard low-enriched uranium (LEU) fuel supply chain, with the core and primary loop entirely encapsulated within a factory-prefabricated fully sealed steel containment structure weighing approximately 1,000 tonnes, significantly reducing research, development, and manufacturing costs. In addition to the domestic U.S. demonstration, the company is currently also advancing the licensing application for a four-unit PWR-20 plant at the "Prosiect Egni Glan Llynfi" clean energy project in South Wales, United Kingdom.