Chevy Volt engine won't recharge the battery after all

DETROIT — Remember when we wrote that the 2011 Chevrolet Volt would be able to run 40 miles on pure electric power and then fire up an onboard four-cylinder engine to recharge the batteries?

Turns out, that's not at all true.

In contrast to popular (and our) impression, once a driver uses up his 40 or so miles of electric power, the 1.4-liter gas engine generates electricity to power the electric drive motor, but does not recharge the batteries. After the 40 or so miles, the battery becomes 400 pounds of uselessness, at least until the owner can plug the car into the electrical grid for a recharge. This means that regardless of how far one drives the Volt, the driver will only ever get up to 40 miles of electric-only range.

Our confusion and that of much of the media corps might have to do with the fact that the company once wrote this: "When the battery is depleted, a 1-liter, three-cylinder turbocharged engine spins at a constant speed, or revolutions per minute (rpm), to create electricity and replenish the battery."

That was from a press release written for the 2007 Detroit Auto Show, where the Volt concept was unveiled. A release from the day of the production prototype's reveal reads, "a gasoline/E85-powered engine generator seamlessly provides electricity to power the Volt's electric drive unit while simultaneously sustaining the charge of the battery." And by "sustaining" GM says that it means only that no additional power is drained from the batteries. Get it?

What this means to you: It's not a deal-breaker and if you travel less than 40 miles per day, it won't make any difference. But for the record: The Volt's gas engine will not recharge its batteries