The Factory-Built Reactor Is Coming to Tennessee

Radiant secures $300 million to build portable nuclear reactors in factories, aiming for a 2026 construction start and 2028 deployment

20 Dec 2025

Private capital is flowing into the advanced nuclear sector as developers race to commercialize smaller, more flexible alternatives to traditional reactors. Radiant, a California-based startup, announced in December 2025 that it had secured more than $300 million in new funding to accelerate the development of its portable nuclear microreactors. The capital raise stands as one of the largest private investments specifically targeting microreactor technology in the United States.

The funding round was led by Draper Associates and Boost VC, with participation from a diverse group of backers including DCVC, Founders Fund, ARK Venture Fund, and Chevron Technology Ventures. These investors are supporting a shift toward compact reactors designed to provide reliable, carbon-free electricity to industrial sites, military installations, and remote communities. The surge in interest reflects a broader industrial effort to meet rising power demand while strengthening energy resilience through low-carbon generation.

Radiant intends to use the capital to finalize its reactor design and begin construction of a specialized manufacturing facility in Oak Ridge, Tennessee, in 2026. Unlike traditional nuclear projects, which are often bespoke, multibillion-dollar builds that take a decade or more to complete, Radiant’s strategy relies on mass-producing standardized units in a factory setting. Doug Bernauer, the company’s chief executive, said the financing allows the firm to transition from research and development toward commercial execution and scaled production.

This investment underscores a structural shift in how advanced nuclear technology is financed. While large-scale plants typically rely on heavy government subsidies or regulated utility partnerships, microreactor developers are increasingly drawing venture capital and private equity. Investors are betting that factory-built systems can significantly shorten construction timelines and improve cost predictability, potentially unlocking distributed power markets that were previously inaccessible to nuclear energy.

Significant hurdles remain before these systems reach the grid. Any new reactor design must navigate a rigorous federal licensing process, and the domestic supply chain for specialized fuel is still in its early stages of expansion. Furthermore, the company will need to convert early interest into firm customer contracts to justify the costs of a full-scale manufacturing operation. Still, if Radiant meets its 2028 deployment targets, the project could provide a blueprint for the commercialization of next-generation nuclear power in the United States.