Regardless, an all-electric car is going to be pushing 90% thermal efficiency - transforming energy into acceleration. A combustion car isn't going to break 40%

Regardless, an all-electric car is going to be pushing 90% thermal efficiency - transforming energy into acceleration. A combustion car isn't going to break 40%. Exotic tech like variable timing and taking cylinders out of service isn't going to get huge gains - they're actually a lot of work for tiny gains, because all the huge gains have already been had. Moreover, electric cars will get that efficiency with no compromise in performance, unlike combustion cars with tiny, weak, "fuel efficient" motors. A Tesla Model S is the fastest car in its class, as well as the most efficient. The only big win for combustion-based cars is the range potential, because the energy storage of liquid fuels is so much denser. I don't expect to see electric commercial aircraft in my lifetime. But biomass-based liquid fuel? Sure. It just won't be cost-competitive with solar/wind into a battery. It'll be limited to specialized applications where power/weight matters.