Hybrid 5 Series is a green muscle car

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The ActiveHybrid 5 is powered by a 3-litre, 6-cylinder turbo petrol engine mated to an electric motor.

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ROAD TEST - BMW ActiveHybrid 5

Suddenly it’s raining hybrids. The exclusive realm formerly unique to the Toyota Prius is now occupied by an ever-expanding list of petrol-electrics to satisfy the green consciences of auto companies, and some of their customers too.

BMW, more well known for its exploration of hydrogen as an alternative fuel for the slightly more distant future, has for now hopped onto the hybrid bandwagon with a petrol-electric version of its Five Series sedan called the ActiveHybrid 5. It will roll out hybrid versions of the 7 Series and 3 Series ranges later this year.

This is BMW, so rather than convert one of its more modestly-powered Five Series derivatives into hybrid-hood, it has chosen the high-performance 535i for the electric makeover.

Rather than a quest for outright fuel economy and planet-friendly emissions, the ActiveHybrid 5 is a muscle car with a green conscience, because who says you can’t reduce your carbon footprint and have some fun at the same time, right?

The petrol power comes from the celebrated 225kW/400Nm 3-litre straight six turbo that provides muscle to various fast Beemers, mated to an electric motor charged by lithium-ion batteries that boosts total outputs to 250kW and 450Nm. As with the regular 535i, an eight-speed auto feeds power to the rear wheels.

The car is able to drive on battery power alone over a maximum distance of 4km at a time.

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Charging of the battery takes place primarily during coasting or braking, and the engine can shut down while coasting at speeds of up to 160km/h. As a fuel-saving aid, an Eco Pro setting (alongside the existing Comfort, Sport and Sport+) relies on more electric power and coaxes the throttle and transmission into a more relaxed, energy-conserving mode that makes the car feel like it’s on valium.

There’s also a start-stop feature which switches off the petrol engine when you come to a halt, and fires it up again when needed (the climate control runs off the battery so the cabin stays cool even when the engine’s taking a nap).

EV MODE HARD TO ACHIEVE

The car’s able to drive on battery power alone over a maximum distance of 4km at a time, but I found this is only when you feather-foot it like a nervous teenager in their first driving lesson. In real-world driving our test car seldom stayed in electric mode (when under power) for more than a couple of hundred metres at a time.

With the ActiveHybrid 5 claiming a fuel consumption of 7 litres per 100km versus the 7.9 litres of the standard 535i, along with lower C02 emissions of 149 g/km versus 177, the numbers look very attractive.

Attractive if not necessarily realistic, as our ActiveHybrid 5 test car averaged 10.3 litres per 100km in a combination of town and freeway driving, and only with extremely conservative driving managed to slip into the high nines. If fuel consumption is a priority, a better option is the diesel-powered BMW 530d which averages around 7 litres per 100.

Cabin majors on style and luxury.

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The extra juice provided by the battery does make the hybrid Five a little quicker than the already very frisky 535i, however, and in our Joburg-altitude tests it dashed from 0-100km/h in 5.9 seconds versus 6.2, and the quarter-mile in 14 secs versus 14.4. The lithium-ion battery seems to maintain its charge longer than other hybrid cars we’ve tested, and we were able to do several full-throttle sprints in our high-performance tests without the power progressively dropping off due to battery drain.

The hybrid powertrain adds about 75kg to the car’s mass but it’s not enough to noticeably affect driving dynamics, and the car delivers the fleet-footed but comfy ride of any Five Series. The transitions ‘twixt petrol and electric modes are imperceptible and all you feel is a smooth and lusty power delivery.

To accommodate the lithium-ion battery the boot’s 45 litres smaller than the regular Five Series though, and further limiting practicality is that the rear seats don’t fold down.

VERDICT

Petrol-electric hybrids have cleaner emissions than diesels, but apart from this moral or ideological reason for choosing a hybrid car, it’s still a very expensive option. In terms of affordability and fuel economy, diesel cars still trump hybrids hands-down and the BMW ActiveHybrid 5 is no exception.

The Five Series is an excellent car and I haven’t met one I haven’t liked. It’s a master class of sophistication, luxury and driver appeal but I think this version’s more a case of BMW needing to be seen to be on the hybrid bandwagon, rather than really expecting to sell many units.

The thing is the numbers just don’t make sense. At R760 977 the Active Hybrid 5 is a hefty R76 590 pricier than a regular 535i, and a full 90 grand more than a 530d which gives similar performance with much cheaper fuel bills.

-Mercury Motoring