Driving the Volt

Continued from page 1

The test car didn't quite have the same performance as the final production version of the car, Weber says. For example, the initial power delivered by the motor has been scaled down a little because the jolt could be too much for the nonproduction parts in the test car. He says that the performance was at about 80 percent that of the production car.

The final car will contain a few additional features, including an extra horn designed to warn pedestrians that the almost-silent car is approaching without blasting them with the regular car horn. It may also include a system that uses GPS to help control when the car shifts from battery-only mode to using the generator. Normally, this happens when the charge level in the battery drops to 30 percent. If the car knows that you're almost to a charging spot, it could postpone the switch, allowing the level to drop lower, thereby conserving gasoline.

The test car is noticeably less powerful than the Tesla Motors Roadster, the only highway-capable electric car for sale in the United States now. But that comparison isn't fair: the Tesla is a tiny sports car designed for high performance, and it costs more than $100,000. The Volt is meant to be an everyday sedan, and it's much cheaper: it's expected to cost about $40,000.

The Volt has more power than a Toyota Prius and feels more responsive, perhaps because it gets all of its power from the electric motor, whereas the Prius gets most of its power from an internal combustion engine. (In the new Prius, the combined power of the electric motor and engine is 134 horsepower, of which only 36 horsepower comes from the battery. ) But the Prius only costs about $22,000.

The performance of the Volt will be important. By the time the Volt comes out next year, it will face a very different market than the one today--one in which there will be serious fuel-efficient alternatives. In addition to there being a larger number of conventional hybrids, other plug-in hybrids will either already be for sale, such as one from Fisker Automotive, or will be soon. Toyota will have already been testing hundreds of its own plug-in hybrids, which will include a smaller battery pack and rely more on the gas engine. What's more, several electric vehicles will be for sale--at first to commercial and government customers, but more and more to general consumers--or they will be on the way, including cars from Mitsubishi, Subaru, and Tesla.