[Animats]

There is a lot to be said for big, strong containment vessels. Fukishima's was too small and overpressure broke it open. Chernobyl didn't have one. Three Mile Island had a good one.

Many of the "small modular reactor" schemes say they don't need a big, strong, expensive containment vessel because, reasons. You can read those arguments for NuScale in NRC documents. The prototype was going to be built at the Idaho National Laboratory, formerly the National Reactor Testing Station, which is in outer nowhere, just in case.

[lazide]

If I remember correctly, part of the issue has been supply chain - the equipment necessary to forge the large steel parts necessary for these containment vessels are few and far between - and now all foreign.

[https://www.newequipment.com/plant-operations/article/219218...]

[jasonwatkinspdx]

Just to be fair, a big reason Nuscale went to the Idaho site is it'd streamline approval.