Europe needs hyperscalers (lots of them) [LWN.net]

Europe needs hyperscalers (lots of them)

Posted Feb 12, 2026 15:38 UTC (Thu) by Wol (subscriber, #4433)
In reply to: Europe needs hyperscalers (lots of them) by malmedal
Parent article: FOSS in times of war, scarcity, and AI

Don't remember the technology - was it AGR? I remember our AGR reactor technology got overwhelmed by the American PWR reactors, despite being much safer.

Iirc it used deuterium (heavy water) as the moderator, so if it got hot, the moderator boiled away and the fast neutrons escaped without being captured and driving fission.

(I thought the main reason for Chernobyl was the operators disabling the safety features "to see what will happen"!)

Cheers,
Wol

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Europe needs hyperscalers (lots of them)

Posted Feb 12, 2026 17:38 UTC (Thu) by malmedal (subscriber, #56172) [Link]

> I remember our AGR reactor technology got overwhelmed by the American PWR reactors, despite being much safer.

Don't know if they were safer, but it's clear they were more expensive.

> Iirc it used deuterium (heavy water) as the moderator

No, graphite for moderator, CO2 as coolant. They used control rods to control the reactivity.

> "to see what will happen"

There are very conflicting stories about the details, but it is clear that it was a pre-planned test, deemed necessary to verify correct operation. It was supposed to be done by the day-shift, but it was delayed, so the unprepared night-shift got the job.