Antares Raises $96 Million in Series B Funding to Accelerate Nuclear Microreactor Development

WASHINGTON--(BUSINESS WIRE)--Antares, an advanced nuclear energy startup, today announced the close of its $96 million Series B funding round. The round was led by Shine Capital, with participation from Alt Capital, Caffeinated, FiftyThree Stations, Industrious, and other investors. The round consists of $71M in new equity capital and $25M in debt for equipment, factory build-out, and uranium procurement.

Antares CEO Jordan Bramble said the new capital will fuel the company’s mission to deliver safe, reliable, and scalable nuclear power solutions. “This funding marks a major milestone for Antares,” Bramble said. “We’re months away from our first reactor demonstration, which will validate our control systems and neutronics models, develop our testing facility, and fabricate our fuel ahead of our upcoming full scale electricity producing prototype in 2027. We’ve raised the capital we need to mobilize to provide resilient energy for our partners at the Department of War (DoW) and NASA.”

Founded just over two years ago, Antares has made rapid progress in technology maturation. The company has raised over $130M in funding to date and put those resources to work building out a 145,000-square-foot facility in Torrance, California, capable of producing 10 units per year. Antares has also secured contracts with the United States Air Force, Space Force, Defense Innovation Unit (DIU), and NASA to advance its technology.

With operations in Torrance, California; Idaho Falls, Idaho; and Aiken, South Carolina, and a team of 60, Antares is working to demonstrate a low-power test reactor before July 4, 2026, and to test its first-of-a-kind electricity-producing demonstration unit in 2027. Production units will be deployed as early as 2028.

Alex Hartz, General Partner at Shine Capital, which led the round, said, “No nuclear startup has turned on a fission reactor this century. Antares is poised to achieve this milestone in 2026, thanks to their design and licensing maturity, fuel supply chain, and swift progress in demonstrating the performance of its underlying components in partnership with Idaho National Lab and NASA. Antares’ reactor will uniquely address needs across defense, space, and critical industries while also serving as a platform for scale-up to higher power.”

Over the summer, Antares conducted an electrically-heated demonstration of its reactor in partnership with NASA at their Marshall Space Flight Center in Huntsville, Alabama. In April, Antares was selected by DIU under the Advanced Nuclear Power for Installations (ANPI) program to provide nuclear power to DoW installations. In August, the company received an allocation of High-Assay Low-Enriched Uranium (HALEU) fuel feedstock from the U.S. Department of Energy (DOE) and was selected for DOE’s new reactor pilot program, which creates a fast-track pathway for reactor demonstration and licensing.

In October, the U.S. Army announced the establishment of a program of record for advanced nuclear energy, called JANUS, targeting reactors from kilowatt class up to 20MWe. With this new funding, Antares plans to compete to provide the Pentagon with resilient energy for critical assets and infrastructure. Antares’ will also propose on NASA’s Fission Surface Power program, which aims to deliver 100 kWe of nuclear power on the lunar surface by 2030.

ABOUT Antares
Antares is building compact nuclear microreactors to deliver reliable, rapidly deployable energy where it’s needed most: remote military bases, austere industrial sites, and, one day, deep space and underwater missions.

ABOUT Shine
Shine Capital is an early-stage venture capital firm that partners with creative, convincing, relentless entrepreneurs to build iconic businesses. Shine manages over $600 million across three early-stage funds and one opportunity fund, and maintains offices in New York and San Francisco. We are lateralist investors who believe that novel opportunities emerge from the dynamic intersections of technology, markets, and culture. We lead inception, seed, and series A financings. Our team is an eclectic composition of talents and backgrounds. While we bring deep expertise across many traditional investing verticals, our strength lies in being aligned strategic partners, both in spirit and in practice.