When BMW does an electric act
Thanks to the electric support, a smaller petrol engine does not mean much less power, while mileage has increased. Is this the future?autos Updated: Aug 29, 2014 10:55 IST
WHY WOULD they plonk an electric motor in a super luxury car such as the BMW 7 series? The question bothered us. Especially considering the fact that the world’s most popular hybrid, Toyota Prius, has had a highly forgettable outing in India. So in the rarified atmosphere of Rs. 1-crore-plus vehicles, who would care really to go green? Questions, questions.
First things first, an inline-6 petrol engine does service in this car, a step-down from the V-8 in the original variant. Looks-wise, there is nothing to differentiate the ActiveHybrid 7L from the conventional 7 series, and the only thing to show off your green conscience are the monograms above the fuel inlet and at the rear end.
The turbocharged 3.0-litre enginen is supported by a massive 40 KW electric motor that nestles between the engine and the transmission, powered by a trunk-mounted lithium battery (which rules out a spare tyre. Remember that).
This set up sends 350 BHP of power and 450 Nm of torque to the rear wheels through an eight-speed automatic transmission, with the motor covering up for the smaller engine. The car can hit 100 kph in 5.7 seconds - a second slower than the petrol variants, but faster than the diesel one’s 6.4 seconds.
Since the whole issue is about the ecodrive of the hybrid, we will take the bells and whistles of luxury for granted, without dwelling on the 16-speaker Harman Kardon sound system or the six-rotation ball massage feature on the rear seat or the independent entertainment system for the passengers or the fully adjustable fore-seats or the oodles of legspace, climate control etc.
Select the ECOPRO drive mode, and we are in electronic business (other modes are Comfort, Comfort+, Sport and Sport+, which change the handling, suspension and traction progressively). Stamp on the throttle, and the car takes off in trueblue BMW fashion. There is no questioning the power, even if the 0-100 sprint is ‘slow’.
The subtlety comes when you abandon excitement, and tread on the throttle with caution. The RMP needle sort of stops, but the vehicle continues to move. This, then, is the electric motor at play, with the main engine on standby. Coast at about 50 kph, and the RPM stays firmly at zero — the highly capable motor even keeping the aircondition and other peripherals going, in addition to the car.
The car sails along with a dignified majesty, no noise, and little trouble. Step on the throttle, and the petrol engine kicks in again, and all is normal. It also kicks in automatically if the road slopes up, or the battery runs out of juice.
Now, we can write about this experience all we like, but till you go take a test-ride, you would not be able to appreciate what we’re talking about.
So let us get down to brass tacks. What exactly is the purpose of this car? The highly efficient diesel 730Ld Eminence and the 730Ld Signature retail at Rs. 1,02,90,000 and Rs. 1,22,00,000 (ex-showroom) respectively. The much more macho petrol 750Li Eminence and the 760Li Eminence cost Rs. 1,39,90,000 and Rs. 1,86,90,000 respectively.
The hero of this story, the ActiveHybrid 7L, is delicately placed in-between, at Rs. 1,35,00,000. The top speed is electronically regulated at 250 kph across the board.
In fuel efficiency, the ActiveHybrid promises almost double the mileage of the V12’s 7.5 kpl. But the diesel delivers 16.5 kpl. Overall, a more costefficient deal. Not to talk of the expense somewhere down the line, when the massive lithium ion battery needs to be replaced.
Having said that, hybrid is likely to be the future of green efforts at least in the mediumterm, with trueblue electric cars still some distance away from blockbuster responses. The performance of a petrol car with the mileage of a diesel — almost — is to be lauded.
These are numbers. Buying a car is a decision from the heart. Will it tug at your heart?