Nuclear submarine power plants are not in any way a technology useful for utility scale power generation.
To start with they use fuel enriched to weapons grade.
They aren't cost effective vs the amount of power produced, and the designs don't scale up to utility scale power.
Submarine plants are not some sort of miracle SMR we can just roll out.
The Navy is willing to page cost premiums a utility company cannot, because for the Navy it's about having a necessary capability. There's no economic break even to consider.
I thought I'd mention that ship supplied short power has been a thing for ages. USS Daniel Webster even trained for this for new years eve apocalypse nothingburger. And its almost always been used for only powering something critical. Today's subs are <10MW. Nothing for utility scale. I can't imagine the economics are ever good. More of a: we've already got this boat.
Secrecy isn't the obstacle here. Naval reactors are optimized for combat performance, costs be damned. They aren't economically efficient for commercial power generation.
At least Russia is doing fine with SMRs, thought the fuel enrichment level is around 20%. They are building new reactors all the time and they seem pretty efficient. E.g. they have even floating nuclear plant: https://en.wikipedia.org/wiki/Akademik_Lomonosov
I'd be fine with us just having the USA navy operate them we build them for carriers and subs just double or triple the order and plug em into the grid.
Submarine reactors run on super high enriched fuel instantly one could instantly repurpose into a bomb. Lots of gen 4 and 5 reactor designs that combine low cost, compact footprint, and running on less expensive and carefully controlled fuel.
