[MetroMPG]

Definitely not a Beta/VHS issue. Both types of motors will co-exist forever. AC is generally more expensive to implement, but offers other benefits (usually higher efficiency, easier to regen).

I don't want to rain on the parade but Lostcause has raised some good points. Without a very high budget, a highway capable series hybrid will be difficult to pull off, and will not be much more efficient than the gas car.