Technically, the combustion engine in any hybrid vehicle is a range extender, but the term commonly refers to gasoline-fueled generators that are used to charge an electric vehicle’s battery pack but aren’t used to directly power the wheels. This is the set up used in “series” or “inline’ hybrids like the Chevy Volt
, which differs from parallel hybrids like the Toyota Prius
, where the wheels can be driven by the electric motor or the internal combustion engine (ICE). Researchers at the German Aerospace Center (DLR) have developed a new type of range extender that can be powered by a range of different fuels.
In an effort to overcome one of the main drawbacks of battery electric vehicles, Volvo is initiating development of a hydrogen fuel cell that is expected to increase an electric car’s operating range by up to 250 km (155 miles). In the first phase of the project the company, together with Powercell Sweden AB, will conduct a study into a Range Extender, which consists of a fuel cell with a reformer that breaks down a liquid fuel – in this case petrol – to create hydrogen gas. The fuel cell then converts the hydrogen gas into electrical energy to power the car’s electric motor.
Designed specifically for the new breed of highly efficient series hybrid vehicles, Lotus Engineering’s Range Extender engine was shown for the first time at the 63rd Frankfurt International Motor Show. In a series hybrid vehicle, the Range Extender engine is attached to an electricity generator and provides a highly efficient source of energy to power the electric motor directly or charge the vehicle's battery. The three-cylinder 1.2 liter Range Extender engine is optimized between two power generation points, giving 15 kW of electrical power at 1,500 rpm and 35 kW at 3,500 rpm via the integrated electrical generator. The battery can also power the electric motor which enables the design of a drivetrain with low emissions, optimized performance and acceptable range.