Antares Nuclear announced a $470 million funding round to accelerate the development of compact nuclear reactors for US military installations. The fresh capital consists of $370 million in equity and $100 million in debt. Venture capital firms Paradigm and Caffeinated Capital co-led the raise, with participation from Point72 Ventures, Shine Capital, and Industrious Ventures.
Founded in 2023, Antares operates in Torrance, California, Idaho Falls, Idaho, and Aiken, South Carolina. The startup specializes in microreactors designed for long-term operation without refueling, aiming to power military sites reliably and securely. According to company statements, their Mark-0 reactor recently achieved a critical milestone by sustaining a self-sustaining nuclear fission reaction at Idaho National Laboratory. This marks the first privately developed non-light-water reactor in the US to hit criticality in over four decades. Though the reactor generated only a small output of energy during this test, it did not yet produce electricity.
Next Steps for Mark-1 Reactor
The next model, Mark-1, is poised to generate electricity and is expected to be ready by 2027. Antares has signed firm contracts to deploy these reactors starting in 2028 on US Air Force bases, aligning with a 2025 executive order aiming for nuclear power operations at domestic military facilities by September 2028. This project is supported by the Pentagon’s Advanced Nuclear Power for Installations initiative, and Antares also participates in a Department of Energy program to accelerate commercial nuclear power deployment.
The rising energy needs driven by the expansion of high-demand sectors like artificial intelligence have spurred investments in nuclear startups developing microreactors. These compact reactors offer a clean, reliable power option, especially valuable in remote or highly secured environments such as military bases.
This material is for informational purposes only and does not constitute financial advice.
