[ad#post_ad]Forty miles of electric range has been the magic number for a very long time, in fact it was part of the Chevrolet Volt concept initial press release back in January 2007.

The idea is that about 75% of drivers drive less than 40 miles per day and will therefore not use any gas while driving the Volt.

GM has said all along that the Volt would achieve that objective but has made it clear that driving behavior and environment could change that number in real world situations; the generator will go on when the battery reaches about 32% state of charge no matter how it gets there.

Today GM filed an updated S1 filing with the US Security and Exchange commission in preparation for its IPO. Buried in that 560 page document was GM's first admission of the real world EV range expected from the car:
"When powered only from electricity stored in its 16-kWh lithium-ion battery; the Chevrolet Volt has a typical range of 25-50 miles depending on terrain, driving technique, temperature and battery age"

I had the chance to discuss this with Volt spokesperson Rob Peterson.

"We've always said up to 40," said Peterson. Now we "tweaked the EV range to from 25 to 50."

Peterson explains that GM now has over one million engineering miles with Chevrolet Volt test cars and they are very comfortable with this range which is based on that experience.

He points out some drivers will achieve more than 40 miles of range. "A conservative driver under ideal conditions will get more than 40 miles," he said. "We don't often highlight this potential to go beyond 40"

Peterson also says the 25 mile range is "pretty darn close" to the worst case scenario. This would be extreme cold temperatures, with the cabin heating system at full blast driven by a very aggressive driver going mostly uphill.

Peterson said now that the car is so close to launch, "we want consumers to understand" what types of real world electric range they could expect.

"A moderate driver is going to achieve what their expectations are," he added.

Source ( SEC )