Why do you need a gas powered generator? Why can't they use something that produces the equal or greater amount of torque. Such as the wheels on the volt. If you had the same setup as the volt on a truck you could use the driveline as the propeller for the generator and it produces sufficent rpms as well as torque. That way you never use gas and you never plug the vehicle in an outlet, it would be self- sufficent. Thats where they need to look; not at more gas power self propelled power.