I don't think so: the "operators" boarding on (into) the submarine with their equipments when necessary.
Moreover it is very usual to operate very very close to the coast: last studies are taking into account to launch UUV from subs to explore the the river mouths...
But you still need to get the submarine into position without being noticed. Conventional submarines, even with AIP can't really do that since it needs to, at the very least, pop up for air.
And like Erik said, you're going to need a lot of power if you plan on generating the fuel on site.
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