[Allch Chcar]

Nerys, An EV RAV4 will take a lot more than 10kw-hrs to go 100 miles. If you were driving an EV1 your math might make logical sense. And the average ICE gets more than 20% of the available energy in gasoline. The 80% is approximate but not all of it is energy some is unburnt hydrocarbon.

dcb, You're forgetting to add in the loss of burning the gasoline. It makes a large difference how efficiently the fuel is burnt. Improving the efficiency of a gasoline engine by 1% improves the power to the crank by 4%. Power efficiency isn't always the same as fuel efficiency. If it was we'd all be driving at WOT. Instead the best fuel efficiency is usually around 62.5%-75% before you get into the high fuel:air mixtures. The typical generator might be cheaper upfront but a purpose built generator for the series hybrid will be much more efficient overall. Mechanical drivetrains are approx 85% efficient through a manual tranny and differential. You might get 90% if you ran it in 1:1 but you'd be sacrificing acceleration. Ev motors get away with 1:1 to the differential because they create more from 0rpm even though they eventually run out of power and torque the faster they turn.

Where the series hybrid or the range extended electric vehicle shines is it allows an electric vehicle to still be driven when battery power reaches a certain point. Electric vehicles are far more efficient at using energy and even less polluting using power from a coal power plant than a comparable gasoline ICE driven vehicle. But batteries are very heavy for the amount of energy they contain. A generator that operates at a fixed rpm can be built to be far more efficient than a variable RPM engine and provide acceptable fuel economy should you deplete the batteries to lowest recommended %SOC. So the range is improved.

Most of the hybrids gain fuel economy in the mid to high speed range by minimizing drag and maintaining a better" ideal specific power to speed ratio." I believe it's called BSFC. If you just skipped on the hybrid system and used the ICE you would get better mid to high speed fuel economy only if you kept the low gearing. Your acceleration would be dangerously low. I understand 0-60mph in 30 seconds isn't unreasonably safe but beyond that you'll have to use flashers to get onto the Interstate or even onto a Highway or busy street. Hopefully you would stick to backroads and drive smarter in that scenario.