Consumer Reports Cars Blog: Against the current: The reality of the award-winning Chevrolet Volt

Clearly, reaping the benefits of electric-car use means keeping the Volt’s battery charged up as much as possible. When we did that, and the Volt only used its gas engine occasionally, the car’s on-board computer indicated we were getting six-figure mpg display of 120 mpg or so. But such a fantastic number is misleading since it ignores the cost of the 12 kWh of electricity we were “pumping” into the car every 33 miles or so. Here in the Northeast, or in California, that ends up being about $2.38 (With the national average of 11cents per kWh, it would be $1.38.)