NRC grants TVA first U.S. construction permit for a BWRX-300 small modular reactor at Clinch River, Tennessee
On September 29, 2026, the U.S. Nuclear Regulatory Commission issued its first-ever construction permit for a BWRX-300 small modular reactor — authorizing the Tennessee Valley Authority to build the 300-megawatt unit at its Clinch River site in Oak Ridge, Tennessee.
The permit, welcomed by reactor designer GE Hitachi Nuclear Energy, marks a first for the BWRX-300 design on U.S. soil and a new chapter for American nuclear energy.
NRC issues first BWRX-300 construction permit in the U.S.
TVA submitted its construction permit application in April 2025, moving through the NRC’s review process at a solid clip. The application built on an existing Early Site Permit TVA already held for the Clinch River location — a head start that helped cut down the time to approval.
The NRC’s construction permit for Clinch River is the clearest signal yet that the BWRX-300 is moving from concept to concrete in the United States.
GE Hitachi Nuclear Energy called the decision a significant milestone for TVA, for GVH itself, and for the broader U.S. nuclear industry. Eric Gray, CEO of GE Vernova’s Power Segment, credited TVA’s leadership and pointed to the collaborative role played by both the NRC and the Department of Energy in getting the project this far.
What drove the NRC’s approval
The permit didn’t happen overnight. It followed an extensive NRC review and required sustained, coordinated engagement among TVA, the NRC, and GVH throughout the process.
GVH points to several factors that helped move things along. Early regulatory engagement — starting conversations with the Nuclear Regulatory Commission well before the formal application — let both sides work through technical questions in advance. The BWRX-300’s design maturity also mattered, since the reactor draws on decades of boiling water reactor operating experience. Reviewers weren’t evaluating an entirely untested concept.
Federal policy played a role too. Executive orders aimed at accelerating advanced reactor deployment created alignment between the administration’s energy priorities and the regulatory process, according to GVH. The Clinch River site itself was a deliberate pick — its location within the Oak Ridge nuclear ecosystem, right next to the U.S. Department of Energy’s Oak Ridge National Laboratory, factored into TVA’s site selection and added credibility to the overall project.
What the permit means for nuclear energy deployment
With the construction permit in hand, TVA can now break ground on a 300-MW reactor built around relative simplicity. The BWRX-300 cuts construction complexity through a streamlined configuration and leans on the long operational track record of boiling water reactors. That’s a big part of the pitch.
The bigger idea, though, isn’t just one reactor. GVH executives are framing Clinch River as the foundation for a fleet deployment model — building multiple SMRs by reusing the same design, the same supply chain, and the regulatory lessons carried forward from each previous project.
Jay Cooper, CEO of GE Hitachi Nuclear Energy, put it directly: “A standard design, combined with a predictable and efficient regulatory environment, allows us to apply common technology, licensing experience, supply chain capabilities and lessons learned from one project to the next.”
Clinch River is meant to be the template. If it goes well, the goal is to replicate that experience across future BWRX-300 sites around the country.
Growing regulatory momentum for BWRX-300 across North America
The U.S. permit doesn’t exist in isolation. The BWRX-300 has been stacking up regulatory approvals on both sides of the border, and that momentum keeps building.
In April 2025, the Canadian Nuclear Safety Commission issued Ontario Power Generation a License to Construct the first BWRX-300 at the Darlington New Nuclear Project site. Construction there is already underway, putting Darlington ahead of Clinch River in the build sequence. In March 2026, OPG submitted its License to Operate application for the first Darlington unit, which is currently under CNSC review.
Back in the U.S., another project entered the pipeline in September 2026 when Blue Energy filed the first part of a construction permit application to the NRC for a BWRX-300 planned for a gas-plus-nuclear project in Texas. That application is separate from Clinch River but uses the same reactor design. Each parallel licensing track generates experience — technical, regulatory, and logistical — that feeds into the ones that follow, with the intent of building a shared knowledge base that makes each successive approval faster and smoother than the last.
What this means going forward
The NRC’s construction permit for Clinch River is the clearest signal yet that the BWRX-300 is moving from concept to concrete in the United States. TVA now has federal authorization to start building a 300-MW SMR at a site with deep nuclear history, close to one of the country’s most prominent nuclear research institutions.
What got the permit across the line was a combination of things: a mature reactor design, early and sustained regulatory engagement, supportive federal policy, and a well-chosen site. Across North America, the BWRX-300 is accumulating licensing milestones — in Ontario, in Tennessee, now in Texas — each one adding to a growing body of experience that GVH hopes will make fleet-scale deployment a practical reality rather than a distant goal.
Kelly is an experienced writer with 15 years of experience exploring the big stories that shape our world, from tech breakthroughs and space exploration to climate, energy, and the fascinating quirks of science. She has a talent for turning complex ideas into sharp, memorable insights that stay with readers long after they’ve finished reading.
