Also it's all electric so it poses the usual problems like the added complexity of an on-board electric generator or the added weight and cost of a battery system.
Like fitting supercooled tesla-power magnets to a moving vehicle, perhaps.
> the added complexity of an on-board electric generator
But you don't need that if the vessel is electric-powered, like a nuclear-powered sub; and I believe some modern warships use a traditional motor to drive a generator, which drives an electric motor for propulsion (i.e. an electric ship powered by a fossil-fuel generator).
Yep.
> I believe some modern warships use a traditional motor to drive a generator, which drives an electric motor for propulsion
Sure, like a diesel-electric locomotive.
It turns out in some situations it's better to eat the conversion loss from electric generation rather than using a direct mechanical linkage, because then you can use flexible cables and electrical control systems rather than a bunch of mechanical folderol
Swapping out your diesel motor with rotating shafts going through your hull and an alternator to generate electricity for a diesel generator that just generates electricity is reducing complexity, not adding it.
so, the difference is between props vs. no props, which is big.
But they too have alternators (and/or dedicated generators)... because it turns out electricity is really useful.