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How the BMW X6 ActiveHybrid Works

BMW X6 ActiveHybrid Design
Rear view of the BMW X6 ActiveHybrid concept during combustion mode (above) and electric mode (below).
Rear view of the BMW X6 ActiveHybrid concept during combustion mode (above) and electric mode (below).
Courtesy of BMW USA

Like the ordinary, non-hybrid X6 model, the BMW X6 ActiveHybrid's exterior design is the first thing people will notice. Similar to the Volkswagen CC and Mercedes-Benz CLS, it uses a curving roof line to give off an aggressive, sports car-like look. In fact, BMW doesn't call it an SUV, but rather a "Sports Activity Coupe" -- despite having four doors and not two.

The X6 rides on big, 21-inch tires and has a unique front bumper that adds to its powerful look. It's not for everyone, though -- the car's looks have been equally praised and criticized in the automotive press.

The car is mechanically similar to BMW's more conventional SUV, the X5, but the curvy roof comes at the cost of some rear headroom and hauling ability. The X6 only seats four people in two rows of seats, as opposed to the X5's three rows. The X6 is also lower and longer than the X5.

Inside, the X6 has a number of high-tech features. Its gear selector looks more like a video-game joystick, where the driver can toggle it up and down to select different gears. There's also the latest version of BMW's iDrive, a knob and computer screen that lets the driver control the audio, climate and navigation systems.

The car also has a number of unique safety features designed to make it confident on every kind of road surface. The X6's xDrive all-wheel-drive system and Dynamic Performance Control distributes the engine's power between any of the four wheels depending on conditions. This allows the car to have more agile and exact handling than you'd expect from a car that weighs more than 5,000 pounds (2,268 kilograms) [source: Emmerson].

The hybrid concept, unveiled at the 2007 Frankfurt Auto Show, boasts some unusual features that accentuate its ability to run on electric power. For example, aluminum plates underneath the car move out to cover up the exhaust tips when the car is running solely on the electric motor [source: Automobile Magazine].

In the next section, we'll find out what makes the BMW X6 ActiveHybrid tick, and how its electric motor is used to boost both fuel economy and performance.