Apollo Atomics Raises $26M Seed for Compact Steam Generator That Could Shrink Nuclear Reactors 40x

Apollo Atomics, a Y Combinator Spring 2026 company co-founded by CEO Assil Halimi and Drew Walker, closed a $26 million seed round to commercialize a factory-manufacturable steam generator roughly human-sized versus conventional units several stories tall. Based on MIT research, the design could shrink reactors 40x and cut production costs to a fifth of existing designs. A demonstration reactor precedes a 2028 commercial target.