Now that the mud has settled a bit on this thread, how about stirring it up?
This is an unusual creature with a motor / generator on the tail shaft of the turbo. With light loading, you spin up the turbo with the motor and it becomes somewhat like a supercharger. Under load, the turbo spins the generator and generates power for the vessel. I can't imagine a generator spinning in 120,000 RPM but it could be geared down, although their movie does not depict a gearbox. Instead it probably generates DC at some amazing voltage where it is stepped down to something useful and either used or stored.