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Nissan revealed a new drivetrain it developed, combining a gasoline engine with an electric propulsion system. Although hybrid gasoline-electric drivetrains are now common among automakers, the new Nissan system, called e-Power, only uses the gasoline engine to charge the battery pack, not to drive the wheels.

Although this type of drivetrain, sometimes called a series hybrid, is not entirely unique in the automotive world, Nissan claims e-Power's compactness makes it the only one suitable for a compact car.

Automakers have been embracing electrification, whether in hybrid form or as a pure electric vehicle play, to help reduce carbon dioxide emissions and use less fossil fuel. Electric vehicles comprise a tiny percentage of vehicle sales currently, partly due to their limited range and long battery recharge times. As a means of making electric vehicles more practical, both Chevrolet and BMW have developed what are sometimes called extended range electric vehicles, which use an onboard generator to supplement the battery charge.

Of the e-Power system, Nissan says that it uses technology developed for its Leaf model. At over 250,000 sales, the Leaf enjoys the status of being the world's most popular electric car. However, e-Power allows use of a smaller battery pack, reducing cost and weight, and allowing its use in smaller cars.

With e-Power, an electric motor drives the car's wheels, using energy from an onboard battery pack. When the battery pack's charge gets low, the gasoline engine turns on to recharge it. The car can also be plugged into an electric vehicle charger, to help minimize use of the gasoline engine.

Nissan's press material shows its Note compact car using the e-Power system. That model is known as the Versa Note in the US. However, there is no mention yet of when a production car using the e-Power system might become available.