This reminds me of SSTAR. which is 50 ft long rather than 20 ft. IIRC there are a few of these self-contained 'plug-in' reactors in the works. Not as a response to PO/CC, but simply because the technology has matured enough that you can tear up a Third World country's coal-fired power station and swap in a tamper-proof reactor.
Turbines, generators, water - all facilities already there, just throw in a new heat source and leave. It'd be a hell of a lot quicker and cheaper than building an entire new nuclear reactor facility. When the fuel runs out after a few decades, just ship the whole thing back and ship in a replacement.
Micro-nuclear reactors that only take up 1 room?
Moderators: Alyrium Denryle, Edi, K. A. Pital