The petrol-electric hybrid version of the BMW 5 Series sedan will be on show in Geneva
Parallel to the world debut of the new BMW 5 Series Sedan at the 2010 Geneva Motor Show, BMW is also presenting the BMW Concept 5 Series ActiveHybrid
The ActiveHybrid 5 Concept features a hybrid system consisting of a twin-turbocharged and direct injected petrol six-cylinder, an eight-speed automatic transmission and an electric motor running on lithium-ion batteries.
The electric motor is rated at 54hp and is connected to the engine via a special clutch. In overrun and when applying the brakes, the electric drive systems acts as a generator developing electric power fed into the battery. This converts kinetic energy otherwise wasted as heat in the brake system into electric power saved for later use.
The system is claimed to improve fuel economy by up to 10% and also allows electric-only driving in city traffic. It comes with an engine stop-start system that will switch off the combustion engine when stopping at the traffic lights, a road junction, or in congested traffic.
BMW has also added navigation system data into the control software that manages overall energy consumption among the engine, motor, and battery. The sat-nav can predict obstacles such as hills, corners and traffic obstructions that could affect the battery life. The car can then charge the battery during the journey and then turn off the engine before it reaches its destination, finishing the trip on electric power alone.
BMW says this "forward-looking function" can extend the car's all-electric range by as much as 30%, though no actual figures have been released.
Read a review of the BMW 5 Series sedan here.