BMW presented a pair of hybrids yesterday—both packed with V8 engines—at the Los Angeles Auto Show. The old news is the BMW X6
full hybrid crossover, which debuted last year in Frankfurt. The new item is the BMW 7-Series mild hybrid concept, which promises a 15 percent reduction in fuel consumption.
Unveiling the 7-Series hybrid, Dr. Klaus Draeger, BMW board member, said, “What does that mean for customers? The highest level of efficiency in the luxury class combined with the best dynamic performance among hybrid vehicles.”
In other words, the company has stuck to its guns: no compromise in performance and a very modest improvement in fuel efficiency. It’s expected that the 7-Series hybrid will top out in the mid-20 mpg range on the highway—pretty good for a two-ton full-size vehicle. BMW is eking out this mileage by using a start-stop system, regenerative braking, and low rolling resistance tires.
The powerful twin-turbo 4.4-liter gas V-8 delivers 400 horsepower and 450 lb-ft. of torque with the 120-volt electric system adding some auxiliary power. The heart of the system is an AGM (absorbent glass mat) lithium ion battery pack stored in the trunk. An electric motor integrated into the transmission replaces the alternator and enables the start-stop system.
The BMW approach is similar to the one taken by Lexus with its LS 600h hybrid, using the hybrid system to boost efficiency, but not reducing engine size. BMW calls it Efficient Dynamics. What do we call this luxury vehicle with smidgen of hybrid-ness thrown on top? A half-hearted hybrid that’s out of step with the times.
The new non-hybrid BMW 7 Series arrives in the US in early 2009. The hybrid version remains a concept at this time.