Microreactor company Antares secures $96 million to develop nuclear energy solutions for terrestrial, maritime, and space applications

Antares Secures $96 Million to Advance Microreactor Technology

Antares, a nuclear technology startup, has announced it has raised $96 million in Series B financing to further develop its small modular reactor concept.

This latest funding round was spearheaded by Shine Capital, with additional backing from Alt Capital, Caffeinated, FiftyThree Stations, Industrious, and others. The investment includes $71 million in equity and $25 million in debt financing.

Innovative Microreactor Design Targets Multiple Sectors

The company is focusing on its R1 microreactor, which is designed to generate between 100 kilowatts and 1 megawatt of power. Antares envisions applications in commercial, defense, and space sectors. The R1 utilizes TRISO fuel—uranium particles coated in carbon and ceramic, then embedded in graphite—for enhanced safety and efficiency.

Growing Momentum in the Nuclear Industry

Antares is among several startups benefiting from a renewed surge of interest in nuclear energy over the past half-year.

• Just last week, X-energy, supported by Amazon, secured $700 million in Series D funding, following a similarly sized Series C round earlier this year. X-energy is also developing a reactor based on TRISO fuel technology.
• Deep Fission, which faced fundraising challenges as recently as April, went public through a $30 million reverse merger in September.
• In August, Aalo Atomics raised $100 million to construct a demonstration data center powered by a microreactor.
• In June, Nvidia participated in a $650 million funding round for TerraPower, a Bill Gates-backed modular reactor company.

Large-Scale Nuclear Projects Regain Traction

Interest in traditional nuclear plants is also on the rise. Earlier this month, Constellation Energy, a Microsoft partner, secured a $1 billion loan from the Department of Energy to restart a reactor at Three Mile Island by 2028—a project expected to require $1.6 billion for refurbishment after its 2019 shutdown. In October, Google announced a partnership with NextEra Energy to reopen a nuclear facility in Iowa that was damaged by flooding in 2020.

This summer, Amazon purchased 1.92 gigawatts of capacity from a Talen Energy nuclear plant in Pennsylvania, while Meta committed in June to acquiring clean energy credits from a Constellation Energy nuclear plant in Illinois.

Small Modular Reactors: A Promising Future

While large nuclear facilities are experiencing a resurgence, the Trump administration has expressed strong support for small modular reactors as a key driver for the industry's revival in the coming years.

Antares Selected for DOE Pilot Program

In August, Antares was chosen as one of 11 companies to participate in the Department of Energy’s reactor pilot initiative, which aims to have at least three reactors operational by July 4, 2026—a much faster timeline than is typical for the sector.

Looking ahead, Antares plans to showcase its reactor to the DOE next year and intends to bring its full-scale reactor online in 2027.