As the Pebble Beach Concours ramps up its luxury, vintage and supercar action, BMW is breaking new ground in the high-tech sector of the luxury segment with a pair of hybrids. John Voelcker brought you the ActiveHybrid X6 yesterday, and today, the 2011 BMW ActiveHybrid 7 gets its turn.

Based on the 7-series sedan and featuring a healthy 455-horsepower and 516 pound-foot output from its combination of a twin-turbocharged 4.4-liter V-8 and three-phase synchronous mild hybrid system, the ActiveHybrid 7 manages to merge electricity with performance – it does 0-60 mph in 4.8 seconds – while also boosting fuel economy by about 15% over the similarly-capable 750i.

That’s no mean feat, and though it’s not as big a jump as the full-hybrid X6, it’s about par for the luxury hybrid course. That’s because luxury carmakers don’t use the addition of a hybrid system to max-out the green (or blue) potential of a car, but rather to balance performance with efficiency.

A sophisticated computer system keeps tabs on all of the hybrid goings-on, and gives key info to the driver via special displays in the instrument cluster and the center stack, including real-time analysis of just how much fuel is being saved.

Other unique elements of the new ActiveHybrid 7 include aero-tweaked 19-inch alloy wheels, a special ‘Bluewater’ metallic paint scheme and ‘ActiveHybrid 7′ badges.

Helping the hybrid system with its power-assist duties is a Brake Energy Regeneration system, a de rigueur inclusion that pushes kinetic energy back into the lithium ion battery pack by turning the electric motor into a generator.

On its own, the mild hybrid motor only contributes 20 horsepower and about 155 pound-feet of torque to the overall picture, though the composite output involves some more complex math than simple addition. The electric motor’s power isn’t too shabby considering it only weighs about 50 pounds, however, and draws its power from a 120-volt, 400 Watt-hour battery pack located under the trunk floor, which itself weighs just 59.5 pounds.

The ActiveHybrid 7 goes on sale here in the U.S. next spring, and we can expect pricing and official EPA figures to arrive in the weeks before the retail launch.