A Tinge of Green

At the North American International Auto Show (ending Sunday), GM unveiled its Chevy Volt concept car, a wind-cheating, four-seat electric vehicle that was the sensation of the show. The Volt utters all the sacred shibboleths that EV enthusiasts have longed to hear: The Volt is a plug-in hybrid, which when charged from a wall socket should be able to travel 40 miles in all-electric mode — more than enough to cover most people's daily driving using nary a drop of gas.

Should the vehicle need to go farther, a super-efficient one-liter turbocharged three-cylinder engine onboard will act like a range-extending generator. The numbers suggest the Volt could be capable of up to 150 miles per gallon on trips of 60 miles or less, and 50 mpg on long-distance drives.If GM can get the Volt's lithium-ion batteries to work properly, says David Cole of the University of Michigan's Center for Automotive Research, "it could be the biggest game-changer in 25 years. It's the real thing."