The propulsion of nuclear-powered aircraft carriers isn't electric... it's driven directly from the steam produced by the reactors.

Edit: At least that's the case for US Nimitz-class aircraft carriers. Nuclear submarines apparently come in both types, with electric motors or direct drive steam-turbines, but I guess this ferry is bigger than any of those.

There have been diesel electric surface ships as well going back to WWII, although it hasn't proven a very popular design and they remain an oddity.