Key facts
- Nuclear power startup Antares raised $470 million in a Series C funding round.
- The funding comprises $370 million in equity and $100 million in debt.
- Antares is developing small modular reactors (SMRs) for U.S. military bases.
- The company's Mark-0 demonstration reactor achieved criticality at Idaho National Laboratory on June 4.
- Antares is a finalist in a Pentagon program to test SMRs on Air Force bases.
- The company plans to have its first electricity-producing reactor operational next year, with military deployments starting in 2028.
Nuclear power startup Antares announced on Monday that it has successfully raised $470 million to fund the development and construction of small modular reactors (SMRs) intended for U.S. military bases. The Series C funding round was led by Paradigm and Caffeinated Capital, with contributions from Industrious Ventures, Point72 Ventures, and Shine Capital. This significant investment reflects a broader trend of increasing investor interest in advanced nuclear startups, a surge partly attributed to the booming demand for power driven by AI data center construction and the general electrification of the economy.
The funding consists of $370 million in equity and $100 million in debt. Antares is developing an SMR with a capacity ranging from 100 kilowatts to 1 megawatt, capable of powering approximately 750 homes. The reactor utilizes TRISO fuel, a safer alternative to traditional nuclear fuel, which encases uranium in carbon and ceramic shells. This fuel form is designed to withstand high temperatures and prevent melting.
Antares's demonstration reactor, the Mark-0, achieved criticality on June 4 at the Idaho National Laboratory. The company is currently one of three finalists in the Pentagon's Advanced Nuclear Power for Installations program, which aims to test SMRs on Air Force bases. Antares anticipates bringing its first electricity-producing reactor online next year, with plans for deployments at U.S. military installations commencing in 2028.
This development occurs amidst a wider influx of capital into the nuclear power sector. In April, X-energy raised $1 billion through an IPO, and other companies like Radiant Energy, Standard Nuclear, and Last Energy have secured substantial funding rounds. Antares itself previously raised $96 million in a Series B round in December, bringing its total funding to $604 million.
Despite the investor enthusiasm, advanced nuclear startups face challenges, including an underdeveloped supply chain in the U.S. and difficulties in scaling production. While mass manufacturing is often cited as a way to reduce costs, its benefits typically take over a decade to materialize, and no startup has yet reached this stage. Early SMRs, expected in the early 2030s, may not be cost-competitive with existing power plants, with Lazard estimating costs around $214 per megawatt-hour. Antares has not disclosed its pricing, but its focus on military contracts suggests a strategy to target a price-insensitive customer base.