I kept asking this question and never get an answer, maybe your friend would tell you. How much does charging his Volt add to his electric bill?
He does most of his recharges at work. They have a couple charging stations, likely added with “stimulus money” LOL.
I’m sure if you look over here:
http://gm-volt.com/forum/
You’ll find plenty of info.
To me there’s no $$ savings in the Volt, because the capital cost is so high. You buy it because you enjoy the technology (like my friend), or you’re worried about a fuel shortage (like 1973-74) and must have mobility over relatively short distances.