Radiant, a nuclear firm founded by a SpaceX alum on a mission to replace diesel reactors with easily manufacturable and shippable nuclear microreactors, has closed a $165M round of funding to support its mission.
The Series C was led by DCVC. It also included participation from StepStone, Giant Ventures, Hanwha Asset Management Venture Fund, SGA, Crossbeam Venture Partners, Align Ventures, ARK Venture Fund, Gigascale Capital, HartBeat Ventures, and Pax Ventures—all new investors.
- The round brings the company’s total fundraising to $225M.
- $100M of this round was announced in November alongside a DOE project milestone.
- Andreessen Horowitz, Union Square Ventures, Founders Fund, Decisive Point, McKinley Alaska Growth Capital, Boost VC, Also Capital, Felicis, Washington Harbour Partners, and Chevron Technology Ventures were revealed as Series C investors at that point.
The Radiant mission: Since it was founded in 2020, Radiant has been eyeing a 2026 deployment of a microreactor small enough, reliable enough, and easy enough to deploy that it’s a viable alternative to diesel generators.
Its solution is Kaleidos, a 1 MW electric and 1.9 MW thermal reactor that runs on TRISO fuel and can fit in a standard shipping container.
Radiant has earned significant support from the DOE to build Kaleidos.
- It’s working with the Idaho National Laboratory’s Demonstration of Microreactor Experiments (DOME) test bed to deploy its first prototype.
- The company has also received two GAIN vouchers from the DOE to support development.
- Last month, the DOE picked the five companies that will receive initial allocations of TRISO fuel, including Radiant.
While we’re at it…Just to bring things full circle, the Trump administration’s executive orders have underlined for investors just how strong the need for new nuclear power really is.
“Certainly, the four ground-breaking executive orders on nuclear power signed last Friday create the conditions for dramatic change,” Will Dufton, partner at Giant Ventures, wrote in a LinkedIn post on the firm’s investment in Radiant (its first investment in nuclear tech). “I thought designating energy infrastructure for AI data centres as ‘defence critical’ was most telling: losing the race to AI hegemony is not an option, and we need all the power we can get.”
The next step: With this round of funding, Radiant is hoping to complete the Kaleidos Development Unit, the first test reactor being built at DOME. The goal is a fueled test by the end of next year.
It’s also going to be siting and beginning work on a factory with the capacity to build up to 50 microreactors per year.
Lead Reporter of Ignition
