California-based nuclear startup Radiant has announced plans to build its first factory for mass-producing portable nuclear generators in Oak Ridge, Tennessee, on land that once formed part of the original Manhattan Project, which launched the nuclear age over 80 years ago.
The factory will be located on portions of the historic K-27 and K-29 sites, part of the former Oak Ridge Gaseous Diffusion Plant that was built during World War II for uranium enrichment.
The land was recently purchased from the Oak Ridge Industrial Development Board, and construction is expected to begin in early 2026. Radiant’s facility, to be named R-50 in honor of both its mission and the site’s nuclear heritage, will aim to deliver the company’s first Kaleidos nuclear generators by 2028 and scale up to produce 50 reactors per year in the following years.
“What was formerly the first Manhattan Project site will now be the site of the first portable nuclear generator production,” Doug Bernauer, CEO and Founder of Radiant said. “By 2028, we’ll be rolling out the first factory-built nuclear generator, and within a few years we’ll be producing over a dozen per year.”
Honoring history while building the future
The K-27 and K-29 sites, where the new factory will rise, were once home to vast uranium enrichment facilities that played a crucial role in the development of the world’s first atomic bombs. The Oak Ridge Gaseous Diffusion Plant operated until the late 1980s, after which the K-27 and K-29 buildings were demolished in 2016 and 2006, respectively.
In recent years, Oak Ridge has remained a symbol of America’s scientific and energy innovation. The city’s legacy has been preserved through the Manhattan Project National Historical Park, which commemorates the immense scale and historical impact of the wartime plants. A K-25 Viewing Platform is also being developed to help visitors visualize the original 44-acre building footprint and understand the site’s contribution to modern nuclear science.
Radiant’s decision to establish its factory at this landmark location connects the region’s storied past to a new era of nuclear innovation. The company aims to use Oak Ridge’s unique expertise, infrastructure, and workforce to advance compact, portable nuclear energy solutions designed for modern needs.
“We chose Oak Ridge, Tennessee, because of their strong workforce, the community’s rich nuclear heritage, and the public’s second-to-none nuclear IQ,” said Tori Shivanandan, Chief Operating Officer of Radiant in the public press release. “Just as importantly, the state’s business-friendly environment gave us the immediate regulatory certainty we needed to move fast and be up and running to meet growing customer demand for our nuclear generators.”
The Kaleidos Microreactor: A new generation of nuclear power
Radiant’s flagship product, Kaleidos, is a 1-megawatt failsafe nuclear microreactor designed to provide reliable and portable power without the need for constant refueling. The company envisions the generator serving a variety of applications, from powering remote communities and critical infrastructure to ensuring energy resilience for military operations and data centers.
Founded in 2020, Radiant is among a growing number of firms aiming to make nuclear power more adaptable and accessible. However, the company distinguishes itself through its focus on mass production, which it hopes will make small nuclear generators as deployable and cost-effective as traditional power systems.
Radiant plans to begin testing its first reactor in 2026, followed by initial customer deployments in 2028. The Oak Ridge factory is expected to play a central role in achieving these missions.
By selecting the birthplace of nuclear technology as the site for its first production facility, Radiant is symbolically and practically linking past innovation to future energy resilience.
“We’re excited to start building in just a few months,” Shivanandan said.