Apollo Atomics

Nuclear Energy · Climate Tech · Deep Tech

Funding

Apollo Atomics raises $31M seed for reactors 40 times smaller

By redesigning the plant's largest component, the steam generator, engineers turned a decades-old reactor design into a factory-built product.

• Apollo Atomics closed an oversubscribed $31 million seed round — $26 million in equity plus $5 million in debt — led by FCVC.
• The Cambridge, Massachusetts company is an MIT spinoff founded in 2025 by CEO Assil Halimi, an MIT nuclear engineering PhD, and co-founder Drew Walker, building compact pressurized water reactors.
• Apollo redesigned the steam generator — normally a multi-story, hand-built part — into a person-sized unit with roughly 10x the power density, shrinking the whole reactor's footprint about 40x.
• The compact system is designed to be factory-built, transported by truck, and deployed in under 24 months, with commercial deployment targeted for 2028.
• Apollo says it already has more than 20 gigawatts of signed letters of intent and is targeting electricity costs around 3 cents per kilowatt-hour, aiming to undercut natural gas.
• The raise taps into a broader nuclear-startup boom aimed at cutting costs, even as recent industry projections suggest many advanced reactors won't be cost-competitive anytime soon.
• As AI data centers strain the grid, Apollo is betting that manufacturing scale and regulatory execution — not new reactor physics — are what actually gate nuclear power's speed to market.