Apollo Atomics Raises $31 Million to Scale Factory-Built Reactors

The company, backed by Y Combinator, plans to use the capital to advance its regulatory engagement with the U.S. Nuclear Regulatory Commission and scale its manufacturing capacity. Apollo’s technology centers on a proprietary compact steam system that increases power density by an order of magnitude compared to conventional designs, theoretically allowing for a 40-fold reduction in the reactor's physical footprint. Founders Assil Halimi and Drew Walker are positioning these systems to fill the gap left by traditional plants, which are often hindered by lengthy construction timelines and site-specific complexities.

Apollo is currently developing a three-tier portfolio ranging from the 10-megawatt A-10 to the 300-megawatt A-300, targeting utilities and large-scale industrial users. With over 20 gigawatts of signed letters of intent already in its pipeline, the company is moving toward the construction of its A-1 commercial demonstrator. By leveraging established fuel supply chains and existing PWR operating principles, the team intends to bypass many of the licensing and supply-chain hurdles that have historically stalled advanced nuclear deployment. The round was led by FCVC, with participation from a broad group of venture firms and individual investors including Paul Graham and Ray Rothrock.