Last Energy PWR-5 Reactor Clears Federal Safety Review
The 5-megawatt unit at Texas A&M moves closer to low-power criticality following the approval of its safety analysis.
Updated on Oct. 21, 2026 in Nuclear
Live Poll
Do you support the development of advanced small modular nuclear reactors to meet future energy needs?
In early October 2026, the U.S. Department of Energy approved the final safety analysis for the Last Energy PWR-5 pilot reactor at the Texas A&M-RELLIS campus. This marks a regulatory milestone for the 5-megawatt reactor, which is intended to demonstrate safe, low-power criticality and eventual grid-connected electricity generation.
Why it matters
The project addresses increasing national electricity demand from manufacturing, artificial intelligence, and population growth. By establishing a dedicated proving ground for small modular reactors, the university aims to accelerate the transition from research to deployable nuclear infrastructure.
The PWR-5 is a 5-megawatt small modular reactor currently undergoing safety review. While the site is part of the 3,300-acre RELLIS Energy Proving Ground, the reactor's specific performance benchmarks against alternative SMR architectures remain to be demonstrated in practice.
The players
U.S. Department of Energy
The federal agency overseeing nuclear energy research and regulating safety standards for pilot reactor deployments.
Texas A&M System
A public university system managing the RELLIS Energy Proving Ground to facilitate research into small modular reactor development.
Terrestrial Energy Inc.
A private nuclear technology firm developing small modular reactor designs currently engaged in agreements with the Texas A&M System.
Last Energy
The private company providing the PWR-5 reactor technology for the pilot installation at the university campus.
The details
The PWR-5 project operates within the RELLIS Energy Proving Ground, a facility designed for site characterization and environmental evaluation of advanced nuclear tech. The reactor utilizes a small modular reactor architecture, a design strategy that emphasizes factory-built components to reduce construction complexity compared to traditional field-constructed plants. The proving ground facilitates collaborative testing between private firms, researchers, and government entities to validate core safety systems and operational protocols.
Timeline
In May 2026, the DOE approved the Preliminary Documented Safety Analysis for the project.
In June 2026, the Texas A&M System signed agreements with Terrestrial Energy Inc.
In early October 2026, the DOE approved the final Documented Safety Analysis.
The Tech Race
The PWR-5 project represents a critical validation milestone for the RELLIS Energy Proving Ground, positioning the facility as a central site for testing modular nuclear designs. It competes with other university-led energy research initiatives that are currently racing to prove the viability of small-scale reactors for commercial grid integration.
Residents of Bryan will see the continued expansion of the RELLIS campus as it hosts multiple advanced reactor projects. The current approval focuses on safety documentation, meaning actual grid-level electricity production for the local area remains a future objective.
The takeaway
The DOE approval of the PWR-5 safety analysis moves the project toward physical testing at the RELLIS site. Observers should track subsequent announcements regarding the start of low-power criticality tests to determine the reactor's performance against its projected outputs.
Further reading
For broader context on current developments in reactor testing and licensing, read more in our Nuclear section.
Source note: This article includes information reported by Waco Tribune-Herald.
Live Poll
Do you support the development of advanced small modular nuclear reactors to meet future energy needs?
