Apollo Atomics has raised $31 million in an oversubscribed seed round to commercialize compact pressurized water reactors designed for factory manufacturing and deployment in less than two years. FCVC led the financing, with participation from Y Combinator, Telesoft Partners, Alumni Ventures, Robinhood Ventures, Nucleation Capital, Pelion VC and Duke Capital Partners. Individual investors included Evan Meagher, Paul Graham, Philip Johnston, Matteo Franceschetti and Ray Rothrock.
The MIT spinoff is developing nuclear systems aimed at customers including data centers, industrial operations and utilities.
Apollo is pursuing a different approach from many advanced-reactor startups by continuing to use light water, commercially available low-enriched uranium fuel and established pressurized water reactor supply chains.
Its core innovation centers on redesigning the steam generator.
Apollo’s proprietary compact steam system is designed to deliver approximately 10 times the power density of conventional technologies.
The company said the architecture can reduce overall reactor footprint by roughly 40 times, enabling the system to be manufactured in factories, transported by truck and deployed in less than 24 months.
Apollo was founded by Assil Halimi, an MIT Nuclear Engineering Ph.D., and Drew Walker, a hard-tech entrepreneur and former White House director.
The company has built and tested a working reactor-system demonstrator within MIT’s Department of Nuclear Science and Engineering.
Apollo is pursuing NRC authorization by the end of 2026 for commercial use of the fuel configuration planned for its reactor.
The company’s planned product lineup consists of the 10-megawatt A-10, 50-megawatt A-50 and 300-megawatt A-300.
Apollo reports more than 20 gigawatts of signed letters of intent across its commercial pipeline.
The new capital will fund construction of its 1-megawatt A-1 commercial demonstrator, long-duration reliability testing, vertically integrated manufacturing, engineering and operations hiring and continued NRC work.
