How do you compare the efficiency of an electric Car to that of your friends noisy ICE car? Well the easiest way to do it is to give them you equivalent MPG, but how do you work that out?

Well to work out the equivalent mpg we simple divide the amount of energy in a gallon of gasoline (36,650Wh) by our Wh/mile figures.

As an example lets say your EV gets 300Wh/mile.
36,650 divided by 300 is 122.2 MPG equivalent.

This means that emoto's electric motorcycle with 75Wh/mile gets the equivalent of:
36,650 / 75 = 489MPG!!!

[martinwinlow]

That's US gallons, BTW. A UK (proper!) gallon contains 44016Wh. MW