Nuclear power startup Antares announced Monday it has raised $470 million to build small reactors for U.S. military bases, because nothing says 'energy independence' like a reactor that can power 750 homes but costs as much as a small country's GDP.

The Series C round, led by Paradigm and Caffeinated Capital with help from Industrious Ventures, Point72 Ventures, and Shine Capital, includes $370 million in equity and $100 million in debt. Investors are apparently feeling the heat - not from climate change, but from the AI data center building boom that's making everyone realize we need more juice.

Antares is developing a small modular reactor (SMR) that produces between 100 kilowatts and 1 megawatt, enough for up to 750 homes. The reactor uses TRISO fuel, which encases uranium in carbon and ceramic shells - billiard ball-sized spheres that can be cooled by gases like helium or molten salts. It's touted as safer than traditional fuel, which is good because the last thing we need is a military base melting down.

The company's demonstration reactor, the Mark-0, reached criticality on June 4 at the Idaho National Laboratory. Antares is one of three finalists in the Pentagon's Advanced Nuclear Power for Installations program, which will test SMRs on Air Force bases in Colorado and Montana. They aim to bring their first electricity-producing reactor online next year, with military deployments planned for 2028.

Investors have been flocking to nuclear power as electricity demand surges from data centers and electrification. In April, X-energy raised $1 billion via IPO, while Radiant Energy, Standard Nuclear, and Last Energy each raised nine-figure rounds since December. Antares closed a $96 million Series B in December, bringing total funding to $604 million, according to PitchBook.

But let's not get too excited. Advanced nuclear startups face hurdles like an immature supply chain and scaling challenges. Mass manufacturing benefits take at least a decade to materialize, and no startup has reached that stage yet. The first SMRs, expected in the early 2030s, likely won't be cost-competitive with most new power plants. Lazard estimates new SMRs will cost about $214 per megawatt hour - more expensive than all but the most costly gas turbines.

Antares hasn't disclosed pricing, but given the market realities, it's no surprise they're chasing military contracts. The U.S. military is famously price-insensitive, which is probably the only way a $214/MWh reactor makes sense.