Over at The Guardian, Joseph Romm offers some advice to Chevrolet for its much-vaunted Volt project—namely, reduce the number of miles the plug-in hybrid can travel on battery alone. Currently, Chevrolet plans to give the Volt a range of 40 miles on its lithium-ion battery, after which a gas-powered generator would kick in (and help recharge the battery). But a battery with that sort of range would very expensive, and could make the consumer price-tag of the Volt too high for the car to have much of an impact:

There simply is no other alternative fuel that offers a more affordable and practical path to sharply reducing the transportation sector's greenhouse gas emissions [than electricity].

That said, the lithium-ion batteries required for plug-ins have never been used for this application before. As one battery expert told me: "There are only pilot production of various Li-Ion batteries" around the world. An alternative fuel vehicle expert told me that GM has "already sunk at least $1bn into the Volt and cannot reasonably expect a profit from a $45,000 new car in an economy which is imploding. The actual cost of the vehicle may be higher.

Given the fact that most Americans commute less than 40 miles per day, Romm recommends that the Volt come with a cheaper battery with a range of 20 miles, which would greatly reduce manufacturing costs, and thus, retail prices. As Romm points out, technological innovation and market forces will eventually drive down the cost of higher-range batteries. For now, though, we have to be realistic about what can be achieved, given available technology and the state of the economy. While tax incentives for purchases of electric cars and further government investment in hybrid R&D could make a difference, Romm's vision of a scaled-back, yet workable, plug-in hybrid may be the best way to introduce the futuristic cars into the market.

--James Martin