The first plug-in hybrid to be sold in the United States will likely be the Fisker Karma, which is due out in November. Fisker Automotive, which unveiled the concept version of the Karma in January, recently raised $87 million to help put it into production. A number of other plug-in hybrids, including models from GM, Chrysler, and Toyota, are scheduled to come out in the next few years.

The Karma, a luxury four-passenger sedan, can be recharged by plugging it in; it can then be driven on power from a battery alone for 50 miles. After that, an onboard gasoline generator kicks on to recharge the battery, extending the range by 250 miles between fill-ups. Power from optional solar cells on the roof will be used primarily to cool the car when it's parked, but they could also partially recharge the battery. The car will run on a lithium manganese oxide battery made by Advanced Lithium Power, based in Vancouver, BC. The battery is similar to the one selected for the Chevrolet Volt, a plug-in hybrid due out in November of 2010.

Henrik Fisker, a car designer and cofounder of the company, said at the New York Auto Show last week that the car is part of his effort to show that environmentally friendly cars need not be small and underpowered. To go with its performance, the car carries a hefty price tag of $87,000.

The car will indeed be fast, but it won't be quite as green as some of the other plug-ins that will come out soon, in large part because of its size. Two 150-kilowatt electric motors together deliver 403 horsepower--enough to accelerate to 60 miles per hour in 5.8 seconds. (It takes the Volt about 9 seconds.) But that kind of acceleration is available only in something called "sport" mode, which uses power from both the battery pack and the gas-powered generator. Drivers will need to select the "stealth" mode to rely exclusively on electricity stored in the battery.

The stealth mode is a holdover from the origins of the vehicle's propulsion system. The Q-drive system was developed by Quantum Technologies for military vehicles designed to have a quiet electric mode for "clandestine operations." When the gas generator and battery are used together, the vehicle gets between 35 and 40 miles per gallon. That's still better than conventional performance vehicles, but not as good as the Chevrolet Volt; when its gas generator kicks in after a 40-mile all-electric range, the Volt will get 50 miles per gallon.

Fisker Automotive is one of several small companies attempting to challenge established automakers by producing plug-in hybrids or electric vehicles. The most promising of these, according to Mike Omotoso, senior manager of power-train forecasting at JD Power and Associates, are Fisker Automotive and Tesla Motors, a company that is already producing its first car, the electric Roadster, a small, very high-performance car that can accelerate to 60 miles per hour in less than four seconds. The Roadster runs exclusively on power stored in its battery: it does not have an onboard generator to extend its range. In spite of Tesla's lead in getting a car to market, it is expected to sell fewer cars than Fisker, Omotoso says. That's because the plug-in hybrid design will make the Karma more appealing to consumers who want to travel long distances. (The Tesla Roadster can go 244 miles on a charge, but recharging it takes hours. The Karma can be refueled quickly.) JD Power estimates that Tesla will sell 500 to 800 cars next year, while Fisker Automotive is expected to sell more than 10,000.