Chevy has officially unveiled its Volt plug-in hybrid. If you saw pictures of the concept vehicle you’re probably disappointed in the look of the end result, but it’s very cool anyway, especially for the average commuter: the first 40 miles the car produces no emissions as it runs totally on electric power. A flex-fuel engine kicks in for anything above 40, and GM says the Volt has the equivalent of 150 horsepower and can hit 100 mph.

But understand: Though emissions aren’t coming out of your tailpipe those first 40 miles, they are still being produced somewhere along the line. Your plug-in’s power, after all, comes from a plug. And whatever is sending power to that plug is – if you’re like the vast majority of Americans who depend on traditional power sources – spewing a constant stream of CO2 and other emissions. Research shows driving a Volt or other plug-in hybrid most likely results in reduced emissions, but let’s not kid ourselves into thinking they’re zero-impact.

Volt’s U.S. production is due to begin in late 2010. Will you be among those in line to snatch one up? Let us know by commenting below.