Hey, just do that math yourself.  To charge my 18.7KWH battery overnight (Chevy Volt) it costs $2, soon to be less.   That is about a 1/4 tank worth (if speaking relative to gas)....to fill my Ranger it costs about $65 or $16 a quarter tank.....so that is 8x the amount to drive my Ford Ranger over my Chevy Volt.