By Larry E. Hall
On the way to hybridizing the 750i sedan, BMW engineers had an electrifying idea; they could not only squeeze some additional fuel efficiency from the 4.4-liter V8 engine, they could also make it go even faster! Yup, the 0-to-60 mph time of the ActiveHybrid 7 is 4.7 seconds, making it the quickest hybrid in the world and bests the gasoline-powered 750i time of 5.1 seconds.
As for squeezing some additional miles-per-gallon, the hybrid 7 has an EPA estimated fuel economy of 17/24 city/highway and 20 mpg combined for both the standard- and long-wheelbase model. In comparison, the standard-sized 750i is EPA rated at 15/22/17; the long-wheelbase model is 14/22/17. That’s nearly an 18 percent improvement in fuel economy, a notable achievement for a car that weighs between 275 and 450 pounds more than its non-hybrid counterparts.
The ActiveHybrid 7, like the ActiveHybrid X6 and recently introduced ActiveHybrid 5, is the result of a BMW philosophy called “EfficientDynamics” that has become a mantra that all of its engineers march to. In simple terms it is the pursuit of an athletic driving experience while simultaneously lowering consumption and emissions.
EfficientDynamics covers every conceivable aspect of an automobile, including electrification, with the eventual goal of emission-free driving pleasure in the form of a combustion engine fueled by hydrogen. In the midterm of reaching that goal, hybrid and electric technology will play a significant role in increasing efficiency.
Since its introduction as a 2010 model, the ActiveHybrid 7 has not had any exterior or interior styling changes. For the 2012 model year, the leather dashboard, head-up display, and active and ventilated front seats are options rather than standard features. The standard-wheel base model is priced starting at $97,000; the extended-wheelbase model starts at $101,000.
Mild Hybrid
The BMW 7’s hybrid system cannot propel the car by electric power and therefore is considered a “mild hybrid.” Similar to Honda’s Integrated Motor Assist hybrid system, the ActiveHybrid 7 adds electric boost to the gasoline engine during acceleration and the engine shuts down when the car comes to a stop.
Under the ActiveHybrid 7’s hood resides a tweaked version of the engine that powers the standard BMW 750i, a twin turbocharged direct-injection 4.4-liter V8. The engine’s output is 440 horsepower and 480 pounds-feet of torque – that’s 40 additional horsepower and 15 more pound-feet of torque than the same V8 powering the 750i. A 15-kilowatt (20 horsepower equivalent) electric motor is placed between the engine and a special eight-speed transmission’s torque converter. Electricity for the motor is provided by a compact 120-volt lithium-ion battery pack that self-charges with power reclaimed from braking and deceleration. The engine and motor team up to produce an impressive 455 horsepower and 515 pound-feet of torque, numbers that approach the V12 powered 760i.
Obviously the additional power the ActiveHybrid 7 has over the 750i doesn’t all come from the hybrid system’s 20 horsepower electric motor. BMW won’t reveal any massaging of the V8 engine, but the electrification allowed engineers to discard the starter, alternator and the belt driving the air conditioner’s compressor.
Surprisingly, the power steering still uses the engine to pump its hydraulics rather than switching to an electric power steering system. When the hybrid start/stop function shuts off, it also shuts off the power steering. This makes low-speed stop-and-go driving frustrating.
While the start/stop function is responsible for most of the city driving fuel economy gains, the eight-speed transmission (two more gears than other 7-Series models) plays a big role in both city and highway driving. Tall gears bolster highway numbers to 24 mpg, whereas more choices of gears allow the engine to operate more efficiently through its range of speeds.
Dynamic, Elegant Luxury
Distinguished by long, flowing, dynamically elegant shapes, the ActiveHybrid 7’s look is unmistakably BMW. Leading the way is the Bavarian automaker’s signature twin kidney grilles inspired by the CS Concept. They are large, bold and protrude in a shark-like manner that renders them imposing. On either side, expressive xenon headlamps have LED “eyebrows” that also recall the CS Concept.
The hood is devoid of lines or creases, save for the familiar BMW power bulge. In profile, the hood flows into the sharply raked front roof pillars and the roofline sweeps towards the rear, culminating in BMW’s now signature Hofmeister kink – a term for the counter curve at the base of the rear roof pillar as it meets the body. The long-wheelbase Hybrid 7 has a different roofline than the standard-wheelbase model. It purges the awkward stretched look that plagues other such cars.
For what would otherwise be a broad expanse of sheet metal, the sides have two distinct character lines. The first starts gracefully from the headlamps and then dramatically flows along the shoulder line toward the rear, tidily incorporating the door handles along the way. The second, more subtle line begins from the chromed side-marker lights on the front fender and gracefully fluxes to the bottom of the doors. Smooth contours along the side accentuate the wheels, while the rear emanates power combined with sportiness. The design genius is, all of this works together to hide the vast girth of the car.
Separating the ActiveHybrid 7 from the rest of the 7 Series models are hybrid-specific badges on the rear roof pillars and back of the rear deck lid.
Inside the hybrid, it’s primarily BMW 7 Series business as usual – luxurious efficiency. All materials, a mix of fine leather and polished wood, are first rate. The dashboard takes its design direction from the clean lines of modern furniture and features a black panel display, which creates an instrument cluster out of what is actually a high-resolution screen. Like its gasoline brethren the ActiveHybrid 7 is a driver-first car, with basic, yet splendid, analog gauges.
BMW’s standard menu-driven “iDrive” system has finally been overhauled making it less baffling to operate. It still operates by rotating and nudging a knob-like joystick on the center console, but now features shortcut buttons for controlling the audio and navigation systems, as well as a completely new graphical interface on the LCD display.
In Europe, cars like the 7-Series are referred to as “executive saloons” and are often used as limousines. Indeed, the additional 5.5 inches added to the wheelbase of the extended-length model seems to provide acres of space for rear seat passengers. And to pamper them, buyers can order a center-console refrigerator, a DVD system with screens mounted behind the front seatbacks that are large enough to rival some laptops, and individual bucket seats that are heated, cooled and recline, and include a massaging function.
The 2012 ActiveHybrid 7 offers nearly every comfort and convenience feature the automotive world has to offer, either as standard or optional equipment. Standard are xenon headlamps, parking distance control, remote keyless entry with push-button ignition, leather upholstery, a five square-foot panoramic moonroof and a voice-activated GPS navigation system with a wide 9.5-inch dashboard-mounted color LCD screen. A premium audio system with 15 speakers and a 600-watt amplifier is also standard.
Beyond that, the sky’s the proverbial limit, with a long list of options. For example, the front seats can include optional “active” bottom cushions that inflate and deflate to help prevent lower back pain. The car can be fitted with video cameras at the front bumpers that provide a left-right view of what’s approaching from the side of the car to make pulling into traffic from a sight-obstructed driveway or street safer.
An optional head-up display projects the car’s speed, navigation instructions and other information onto the windshield in the driver's line of sight, while an available Night Vision with Pedestrian Detection system uses an infrared camera to display a negative-image view of what’s beyond the car’s headlamps.
The only downside to the hybrid version compared to the gasoline models is a slightly smaller trunk. Like most hybrid cars, the battery pack is housed in the trunk, reducing the space by one cubic foot to 13 – still enough room for four large golf bags.
The Luxo Hybrid For You?
Needless to say, the 2012 ActiveHybrid is not within the realistic budget of most of the population – it takes a lot of greenbacks to purchase a green BMW 7 Series sedan. But what you get for the dollars spent is not only the “Ultimate Driving Machine,” but also the ultimate in refined luxury and a stunning sedan that delivers fuel economy that just a few years ago was not possible.
For discriminating buyers who like a dab of hybridness with their mounds of horsepower and luxury there are other vehicles to test drive. The Lexus LS 600h L offers the same EPA 20 mpg combined fuel economy as the BMW, but it is only available in long-wheelbase form and the $112,750 price is daunting. Another consideration is Mercedes-Benz’s S400 Hybrid. It doesn’t offer a stretched-wheelbase model and doesn’t come close to the performance levels of the Bimmer, however, it has a more luxurious interior and the V-6 hybrid powertrain has an EPA combined rating of 21 mpg.
While it doesn’t have quite the cachet of other luxury automakers, Infiniti’s M35h shouldn’t be overlooked. It’s a wonderfully designed automobile and the company recently announced the addition of an extended-length version. The hybrid M delivers nimble handling and spirited acceleration plus, the EPA combined 29 mpg rating trumps the others. Perhaps the biggest reason for giving the Infiniti a long, hard look is the $53,700 base price.
The ActiveHybrid 7 is thrifty enough with fuel to make one forget there is 455 horsepower under the long hood. And while it doesn’t have the fuel economy of countless other cars, the hybrid powertrain does nudge the big sedan up a little bit, and every little bit helps.
Reviews
The hybrid 7 is a nicer drive than the V12. Its lighter front end improves agility and it comes to a halt in near-silence -- the engine stops, and the continuing whirr of cooling and A/C systems is almost drowned by surrounding traffic. The throttle response is sharp too. And who’d say no to the additional fuel range.
Motor Trend
Hybrid operation in this electrified 7-series is mostly unobtrusive. Road-blurring acceleration-this ain't your father's hybrid-leads to high-speed serenity, although wind noise is a bit high.
Car and Driver
With it all comes BMW 7-Series comfort, elegance and opulence—four-zone climate control, a leather-wrapped steering wheel with plush leather seats, rich wood-grain accents, ambient interior lighting for night driving, onboard navigation with a high-definition backup camera, and myriad active and passive safety technologies.
Washington Post
Prices are manufacturer suggested retail price (MSRP) at time of publication and do not include destination charges, taxes or licensing.
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