Fiat is developing a hybrid drive system for small cars, such as the Fiat 500, Panda and its forthcoming city car, that operates in conjunction with a dual-clutch six-speed transmission.
The dual-clutch gearbox requires two shafts, one for each clutch. In the new system, an electric motor is connected to one of these shafts, which provides second, fourth and sixth gears, enabling it to bypass the engine and deliver drive to the wheels.
The hybrid drive will be most beneficial in city use. Unlike a petrol engine, an electric motor generates its peak torque from zero revs, which allows it to pull the car in a tall sixth gear at speeds that might equate to just 200rpm for a petrol engine. The transmission is at least two years away.