BMW unveiling two big hybrid models at Frankfurt

BMW announced today the production versions of the BMW ActiveHybrid X6 and ActiveHybrid 7, two very different hybrid models with very different drive trains. Both vehicles will make their world premiere at the Frankfurt Motor Show in September. The Hybrid X6 will reach U.S. BMW Centers in fourth quarter 2009; and the BMW Hybrid 7 will reach America shores in spring 2010.

The BMW ActiveHybrid X6's power train starts with a 400 hp twin-turbocharged V8 gasoline engine and adds two electric synchronous motors delivering 91 hp/192 lb-ft and 86 hp/206 lb-ft, respectively. Maximum system output is 480 hp, and peak torque reaches 575 lb-ft.

Acceleration from a standstill to 60 mph happens in 5.4 seconds, with an electronically limited top speed of 130 mph. Average fuel consumption in the EU test cycle is improved by roughly 20%. EPA ratings will be available closer to the market introduction.

This X6 is BMW's first full hybrid model able to run exclusively on one of its electric motors up to a speed of 37 mph or a range of 1.6 miles. Exceed either of these parameters or push the go-pedal too firmly and the second electric motor will spin up the combustion engine automatically.

Three powerplants require a complex transmission. The Hybrid X6's two-mode automatic transmission features three planetary gearsets, four multiplate clutches, and seven speeds with a manual shift mode. That's all before the power reaches BMW's xDrive all-wheel-drive system where it is shifted between the front and rear axles.

The electric motors receive their energy from an NiMH battery pack positioned beneath the floor of the luggage compartment. This battery pack also feeds electric power to the vehicle's onboard network and is charged using regenerative braking by one or both of the electric motors.

Meanwhile, the ActiveHybrid 7 is powered by an upgraded twin-turbo, direct injection V8 engine from the 750i with electric motor wedged between the engine and the torque converter of the eight-speed automatic transmission. Combined power output is 455 horsepower and maximum torque of 516 pound-feet. The electric motor receives its supply of energy from a lithium ion battery developed specifically for use in this automobile.

The 7 accelerates to 60 mph in 4.8 seconds, while delivering fuel economy approximately 15 percent better than the conventional 750i. Again, official EPA ratings will be available closer to the U.S. market launch.

The BMW ActiveHybrid 7 is the first BMW with automatic transmission to feature Auto Start/Stop to maximize efficiency by avoiding engine idling when stopped. However, the Hybrid 7 doesn't appear to operate in a fully electric mode. A fully electric air conditioning and ventilation system, powered by the 120 volt lithium ion battery pack, means that the A/C remains fully operational when the gasoline engine stops.

Like existing BMW 7 Series models, BMW's ActiveHybrid 7 will enter the market in both regular and long wheelbase body variants.