Chevrolet Europe brand boss Wayne Brannon was talking about the Volt plug-in hybrid when he mentioned an intriguing feature.
Brannon said he goes through most weekdays without using gasoline. But on weekend trips, he said at last month's Frankfurt auto show, "I just switch it into extended range mode, and I drive on fuel until I get there. When I drive in the little villages and towns, I drive in electric mode."
Wait. You can pick the mode you drive in? Yes, Brannon said. European Volts, which go on sale Nov. 3, come with a "hold" mode. That lets the driver conserve the battery charge and use the onboard internal combustion engine to generate electricity. U.S. Volts run first on battery power, switching to the engine when the battery runs down.
"The reason it was important here is we have cities -- like London -- where you don't have to pay a congestion charge if you're running purely on battery," he said. "You save the battery for when you need it."
Any chance U.S. Volts will get the feature? General Motors spokesman Rob Peterson wrote in an e-mail: "There are no plans to add this feature in the U.S., as regulations require the vehicle to operate in its most fuel-efficient/ lowest emission mode first."
The latter point seems to be a gray area. A check with the EPA found that greenest-mode-first isn't exactly a rule. But emissions and fuel efficiency ratings are based on that assumption. So perhaps GM doesn't want to include a feature that might hurt the Volt's ratings.
Another twist at Frankfurt: In a later conversation, Fisker Automotive CEO Henrik Fisker said that when driving the company's Karma plug-in hybrid in California, he switches modes to save battery power for city streets.
So it can be done in the United States.