Apollo Atomics is targeting nuclear power’s cost problem by redesigning the steam generator, the largest and most expensive component in a reactor. Instead of building a new reactor, the startup has developed a compact generator that can be mass-produced and is roughly the size of a person, compared to traditional units that stretch several stories tall. This design reduces a reactor’s footprint by 40 times and allows entire plants to be assembled in factories rather than built on-site, cutting labor and construction time.
The company’s approach focuses on efficiency. Traditional generators use large tubes to transfer heat from reactor coolant to water, wasting potential energy from nuclear fuel. Apollo’s generator replaces these tubes with a metal block riddled with needle-thin channels, improving heat transfer and enabling smaller, cheaper reactors. Apollo projects electricity costs as low as 3 cents per kilowatt hour and aims to undercut natural gas prices.
Apollo has already demonstrated the technology with a 40-kilowatt prototype at MIT and plans to offer reactors ranging from 10 to 300 megawatts. A $26 million seed round, including $5 million in debt, will fund a commercial demonstration reactor slated for 2028. The round was led by FCVC, with participation from Y Combinator, Nucleation Capital, and others.
