Like I said umpteen times -- if you add the embedded energy in electricity to the equation, then you must also add it to gasoline.
And since you can get electricity from renewable sources, and you cannot get gasoline from renewable sources, the ultimate energy is electricity.
If you want to measure the efficiency of a car, then you measure the energy carried in the car, and how much of that its used per unit of distance traveled.
If you want to measure the efficiency of the entire support energy system -- i.e. source-to-wheels, then you have a much hard job. And I posit that either way you measure it, electricity is the cleaner, much lower carbon content form of energy. In fact, between electricity and gasoline -- electricity is the one that has the potential to be carbon free.
Biodiesel would be great also, as would methane from digesters. But petroleum derived gasoline is not even close to electricity.
http://neilblanchard.blogspot.com/20...-infinite.html