Hannah Ritchie in Sustainability by Numbers:
For every dollar of petrol you put, you get just 20 cents’ worth of driving motion. The other 80 cents is wasted along the way – most of it as heat from the engine.
Electric cars are much better at converting energy into motion. For every dollar of electricity you put in, you get 67 cents of driving motion plus another 22 cents of energy that’s recovered from regenerative braking. That means you get 89 cents’ worth out.