Four U.S. startups fired up their first small nuclear reactors, aiming to power AI data centers on-site

Morning Overview ^ | Aug. 28, 2026 | Everett Sloane

[libstripper]

Four American startups have brought their first small nuclear reactors to life, each reaching the point where the reactor can sustain a controlled chain reaction. The companies are chasing a specific goal: generating power on-site for the electricity-hungry data centers behind the artificial intelligence boom. Reaching criticality is a significant technical milestone, though it remains a long way from a fully operational commercial power plant.

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TOPICS: Business/Economy; Culture/Society; Government; News/Current Events
KEYWORDS: ai; data; datacenters; nuclear; nukes; power; reactors

[libstripper]

Really good article explaining what AI is, why it requires so much electricity, the nature of small nuclear reactors and why they could be vital to powering data centers.

[butlerweave]

How about 1 for a Cabin deep in the woods ? LOL

[kiryandil]

Jane Fondle saddened...

[Mr. K]

they use them to power nuclear subs...

[Ken522]

The article doesn’t mention it, but we already have “small” reactors functioning on our submarines and aircraft carriers ...

[Carry_Okie]

We need these reactors all over the country, making it much less subject to terrorism or natural events.

[struggle]

Not only that, but you can use the heated water in data center cooling for power as well.

[Tell It Right]

Deep in the article is contains this gem of realism before getting too excited with the headline:

For all the significance of reaching criticality, the achievement should not be mistaken for a working commercial reactor. Independent experts have urged caution about the surrounding enthusiasm. According to a critical assessment of the sector, much of the messaging around next-generation nuclear for data centers outpaces what the technology has actually demonstrated, and turning early reactors into affordable, licensed, grid- or campus-scale power sources remains a formidable challenge.

[E. Pluribus Unum]

We couldn’t have more nuclear power for decades, but Big Tech snaps their fingers and gets it.

[Red Badger]

How about 1 for a House deep in the suburbs?.........

[exnavy]

Yes, buy making steam and powering a turbine with that steam. That turbine than turns generators etc. you gotta have a means to convert the heat to useable energy.

[Bayard]

Yeah but what about my communist campaign to denigrate the development of the entire US economy by claiming data centers are only for increasing the degeneration of the youth and ending all civil rights?

[Political Junkie Too]

Nuclear reactors are basically steam engines with a steady heat source.

-PJ

[PGalt]

Thanks for posting. BUMP!

[Scrambler Bob]

Just wait till AI realizes that it can use its own nuke plant for a nuclear explosion, thus getting rid of all the troublesome humans.

That is an AI with Democrat level of intelligence.

[Eli Kopter]

Maybe in the future. Don’t laugh.

[Tell It Right]

Not only that, but you can use the heated water in data center cooling for power as well.

I have similar re-use in my home.

1) My attic usually has free warm air (or even hot air) here in sunny Alabama. I use that to help heat my water heater because it's a hybrid water heater with a built-in heat pump. The air intake is ducted from the attic, meaning the water heater takes in air that's usually warm, so that the water heater doesn't have to run as long to find enough heat energy to put into the water tank to heat it up. The water heater runs at only 380W. It takes 2 hours to reheat the tank if my wife and I take back-to-back showers, plus add another hour on average daily for other appliances. So it'll consume about 1kWh of power for showers. Unlike a standard electric water heater heating up a tank in 30-45 minutes, but running at 4kW (consuming a total of 2kWh to 3kWh after showers, plus more for other appliances).

2) The water heater's heat pump produces a byproduct of free cold air (the air it took in through step 1, but with some the heat energy extracted). During the warm half of the year I direct that free cold air into an air receiver of my home HVAC. So during the hours in the day that the water heater runs (and produces free cold air), that free cold air is distributed throughout the house by my home's variable speed heat pump and variable speed blower (almost always on, but low speed). So for a few hours during the day my HVAC is at a lower speed (read: consuming even less power) than it normally would be.

The home HVAC as a variable speed heat pump saves me a lot of power. The hybrid water heater also saves me power. But the two work together better than the sum of their parts and saves me more together.

3) My wife and I have home solar and also do most of our driving in the EV. With the EV getting about 230 mile range when fully charged ("full" being the recommended 80% for local use), and with us driving on average 50 miles per day, we don't need it charged every day. Thus we charge it to 80% on free power days (sunny days). If it rains we don't charge it unless it's rained multiple days in a row (or we have a day that we drove a lot more than usual). When you drive 16K to 18K miles per year on local driving alone, anything you can do to reduce your driving costs is substantial.

The solar saves us money. The EV saves us money. But the two work together better than the sum of their parts.

[miniTAX]

“we already have “small” reactors functioning on our submarines and aircraft carriers”

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They use highly enriched uranium (>20%) which for reasons as stupid, overreaching and arbitrary as most of those put out by the regulatory industry, can NOT be used for civil purpose.

[Mr. K]

so lets use it to power data centers!

[bdfromlv]

predicted in the series EUREKA in 2006