Fox News Dickers With Chevy Volt Mileage

By now, everyone knows that when General Motors (MTLQQ) flashily claimed that the forthcoming Chevy Volt extended-range electric vehicle would get ... 230 mpg!, it was a publicity stunt, pure and simple. That hasn’t stopped various critics from claiming that GM is peddling hallucinatory expectations. The latest to jump on the "Volt230 ... Huh?" bandwagon is Fox News, which has produced this actually rather balanced analysis, but with a diggy headline: “Chevy Volt to Get 32 mpg?”

Not 230, right? Well, the thing is that the Volt’s mpgs could theoretically be infinite, assuming you never have to fire up the gas motor to provide power for the electric engine. That’s unlikely, however, given the Volt’s 40-mile max range on electrons only. Enter the mileage estimates for the gas engine, which is a relative small 1.4-liter, four-cylinder powerplant. The point, of course, is that this engine doesn’t drive the wheels; it provides power to drive a generator that in turn keeps the electric motor spinning.

At this point, with such a serial-hybrid design (versus a parallel hybrid of the Prius type), it’s hard to tell what kind of mpgs the Volt will rack up when its gas engine is working. GM is testing a fleet of Volts to find out. If you read between the line of the Fox News story, the question being asked is “Will the Volt have better mpgs than the Prius?” This makes sense, unless you take into account that the Volt is gradually unbecoming a hybrid and getting lumped in with a new generation of EVs, such as the all-electric Nissan Leaf. Comparing it with conventional gas-powered cars and hybrids doesn’t make sense, because owners will routinely be able to game the whole gas system.

A lot of people are going to buy Volts to have a Volt before everyone else. But once the early-adopter wave is exhausted, you’ll begin to see the car slotted into its natural role, a people mover that can move people 40 miles at a time on a single charge, then be rejuiced overnight off the grid. What if you have to go 50 miles every day? Well, then you’ll probably burn about a quarter to a third of a gallon of gas. Let’s call it a quarter, which would mean than the Volt gets about 40 mpg. That means you’re going to get four days out of every gallon. With a 12-gallon tank, that’s roughly ... 48 days between fill-ups. More than a month and a half.

So maybe we should be thinking less about Volt mpgs and more about Volt fill-ups. Consider this: If you drive 50 miles per day, 320 days per year, you’ll put a more or less average 16,000 miles per year on your Volt.

And fill the gas tank fewer than six times.