A generator or an electric motor don't have a particularly low efficiency or don't wear much? Hybrids happened in locomotives and ships way before cars. Many sh

A generator or an electric motor don't have a particularly low efficiency or don't wear much? Hybrids happened in locomotives and ships way before cars. Many ships have diesel engines turning generators and then have electric motor propulsion. You can replace all 23 MW (consisting of 20 MW propulsion and 3 MW electrical) on one ship with batteries + propulsion motor. Or you can replace just the 3 MW pure electric part with batteries, getting rid of the auxiliary motors and their generators, doing it on 8 ships. In the latter case you don't need the one propulsion motor, that's true, so it might be somewhat better.