The production version of the Chevrolet Volt won't look like the popular concept by the same name, General Motors Vice Chairman Bob Lutz said during a dinner event with members of the press yesterday evening.

GM had hoped to keep the Volt's exterior true to the concept, but wind tunnel tests proved the design was anything but aerodynamic — an essential characteristic for a vehicle that focus on efficiency.

Lutz characterized the wind tunnel tests as a "cruel disappointment." He joked engineers could have probably "put it in the wind tunnel backwards" and got less wind resistance.

Nonetheless, Lutz says GM is 100 percent behind bringing the electric Volt to market in the next few years. He said GM was first "90 percent committed" to the project, but its confidence has risen to new heights.

What makes the Volt different from most hybrids is its gas motor is only used to charge the batteries — it never drives the wheels directly.

The concept promised a range of 640 miles with charged batteries and a full tank of gas. It also touted a range of 40 miles on batteries alone. Lutz said prototypes in early 2008 might be able to exceed that figure, running 45 miles on battery power. He made no mention of progress on overall range or fuel efficiency. The goal is roughly 100 mpg, GM has said.

Expected to go on sale in late 2010, the Volt could sell for as little as $30,000, according to previous reports. Rumors suggest GM plans to sell as many as 60,000 units in the first year of production.