At the 2011 Geneva Motor Show back in March we learned an interesting bit of information about the 2011 Chevrolet Volt's European cousin, the Opel Ampera.
Unlike the Volt, the Ampera is to be equipped with a "battery saving" mode, whereby the driver can hold back the electric mode for when they require it, rather than starting their journey and using up the 40-50 miles of electric range from the get-go. It's also been announced that the European version of the Volt will feature this option.
So should the American Volt - and other range extended vehicles due in the future - be fitted with a battery saver mode?
The reasoning behind the Ampera's mode is to prepare for future European policy that may require some city centers to be fossil fuel-free, and others such as London where electric cars aren't required to pay almost $13 a day in "congestion charge" fees.
If you'd already used up your EV range by the time you got to the center, on a business trip for example, you'd be unable to enter the city. Holding an electric mode for later means when you reached the city limit, you could press the button and glide in entirely fossil fuel-free. No restrictions, no fees.
It's not just a way to get around local restrictions, either.
For the environmentally-conscious, saving the EV mode for crowded cities means reducing local pollution, both in terms of emissions and noise.
You're also likely to get better use from the electric range in a city too - 40 or 50 miles could easily be several days driving around a city, whereas it might be less than one trip on the freeway.
So why is the U.S. market Volt not equipped with the feature? Rob Peterson from General Motors told Automotive News (subscription required) that "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."
Even so, the EPA test doesn't necessarily require the car to be run under its greenest mode first, so on face value it seems like an oversight. However, it's understandable that GM doesn't want to potentially hurt the car's EPA rating, as ultimately that's what sells the car.
The U.S. doesn't currently have the sort of restrictions found in many European cities so currently there is no specific need to hold the electric mode for a later time, and many drivers will still make most of their journeys on electric power alone.
So should range-extended cars have a battery save mode? Not necessarily, but that doesn't mean we shouldn't have the option.