eh.. the thing is, the original, very primitive nuke plants got built in months, not years, and very cheaply per mwh.  Emergency solutions do not look anything like the EPR or the ap1000.

if the alternative is "freezing to death", lead cooled fast breeder designs ripped of soviet sub reactor  designs could be mass produced in factories, and "containment domes" could be redefined to "put it in the cellar". This would not be very sensible, of course, but the laws of physics do actually prevent it. And societies that are in trouble have a very long history of doing things that are not sensible and fixing the problems later.