BMW ActiveHybrid 5 (2012) CAR review

This is the new 2012 BMW ActiveHybrid 5. And if you haven’t guessed already, that means it’s a hybrid version of BMW’s 5-series executive saloon. Essentially it’s an electrified 535i, and rather idiosyncratically the addition of 150kg of extra weight has supposedly improved fuel consumption and emissions by a double-digit percentage.

It’s simpler than the defunct twin electric motor BMW X6 ActiveHybrid, and unlike the ActiveHybrid 7 it can run on battery power alone. Does the BMW ActiveHybrid 5 work in the real world, away from the laboratory? Read on for our first drive review of the new BMW ActiveHybrid 5.

So if the BMW ActiveHybrid 5 is a 535i with added electrical oomph, presumably it’s not slow?

No it isn’t. While local rival Audi uses an electric motor to boost the power of its 2.0T engine, BMW prefers to mate its hybrid powerpack to more powerful petrol engines. The theory is that smaller petrol engines are already very efficient (so the gains would be negligible) and those who can actually afford this expensive technology aren’t the sort to want a four-banger under the bonnet.

In the ActiveHybrid 5 that means a 3.0-litre straight six, with two twin-scroll turbochargers. The 535i’s output is already 302bhp and 295lb ft, but with an electric motor helping out, those figures are pushed to peaks of 335bhp and 332lb ft. There’s no difference in the 0-62mph time though – it remains at 5.9 seconds.

Rather than a Lexus-style CVT gearbox, the BMW ActiveHybrid 5 has an eight-speed automatic into which the 40kW electric motor is integrated. The lithium-ion batteries sit behind the rear seats and cut boot space from 520 litres to 375 litres. All of this adds 150kg to the kerbweight of a 535i, but at least in the official NEDC test, the ability to run for 2.4 miles on electric power improves the figures from 37.2mpg and 177g/km to 44.1mpg and 149g/km CO2. The price for all of this is £46,860, £7920 more than a 535i. Gulp.

But I live in Europe…

But if you live in Europe, where diesel power dominates the executive sector, maybe it’s best to overlook the £44,290 535d. Officially it’s cleaner and greener (52.3mpg and 142g/km) than the ActiveHybrid 5, it’s four tenths quicker to 62mph, a chunky 125kg lighter and it’s got a monstrous 443lb ft. Which is why BMW reckons one-third of production will go to the USA, one-third to Japan, while all its other markets will account for the final third.

So if I don’t live in Europe, or if I’m mad and still want the ActiveHybrid 5, what do I get for my money?

Visually this hybrid 5-series is distinguishable by a set of ghastly ‘ActiveHybrid 5’ badge on the C-pillars, galvanised slats for the kidney grill and matt finish exhausts pipes. A unique Bluewater metallic paint (not named after the shopping centre) is also an option, as are aero-efficient 18in Streamline alloys, and both were on our test car. But buyer beware: 17in wheels are standard, but opt for the bigger wheels to shout about your climate consciousness and you’ll actually worsen the official figures to 41.5mpg and 160g/km. The other optional 18s, 19s and 20s are more detrimental still, recording 40.4mpg and 163g/km.

What’s the BMW ActiveHybrid 5 like to drive?

The ActiveHybrid 5 does what most hybrids can do. It shuts down at traffic lights like a normal stop/start system, and restarts on electric power alone (and cuts the petrol engine in if you’re racing away when the lights go green or are out of battery charge). It helps boost the petrol engine in other acceleration situations too, the electric motor acts as a generator to charge the batteries, and it can run for up to 2.4 miles on electric power alone, and reach an EV top speed of 37mph.

Two things stand out. The first is the use of a conventional automatic gearbox (the electric motor takes the place of the torque converter), which means when you accelerate there are actual gears to shift through. Put your foot down in a Lexus hybrid and the CVT ‘box will hold the revs at droning high rpm. Efficient, but awful on the ears.

The ActiveHybrid 5’s trick is its coasting feature, which shuts down and decouples the engine (at up to 100mph in Eco Pro mode, or 50mph in Comfort mode, and not at all in Sport or Sport+). Obviously it won’t do it if you’re tackling an incline, but lift off on the flat or downhill and the rev counter drops to zero. And you honestly can’t tell when the engine kicks back into lift, besides the needle flicking back up the dial.

The other bonus is that the engine isn’t recoupled as soon you brake, unlike in some other cars. Both Audi’s Q3 and PDK versions of the new Porsche 911 have freewheeling systems that disconnect gearbox and engine, but you’ll inevitably start to pick up speed on a downhill section, you’ll brake, and everything connects up again to give you some engine braking – and instantly kills any chance of economy gains. Not so in the ActiveHybrid 5.

As for the rest of the package, the ActiveHybrid 5 is still excellent to drive, with direct steering, good body control, and a comfortable ride (all the test cars were fitted with the optional Dynamic Damper Control). It was odd (but welcome) to hear a howling and growling straight six under the bonnet, but the added weight of the electrical gubbins means it’s not as quick as you'd expect of a car boasting power and torque figures on par with a 1-series M Coupe.

Verdict

In Europe we’re taxed on CO2, and we doubt many of the people looking to buy a £45k executive saloon are the same people who are aware of a diesel engine’s comparatively high NOx emissions versus a petrol engine.

As for the parts of the world which focus on NOx, unless you can categorically prove that the 150kg heavier ActiveHybrid 5 is kinder to the environment over its entire lifecycle than a 535i – or the additional cost of the hybrid 5 is negated by the punitive taxes imposed upon a 535i – then the conventionally powered petrol 5-series will be a better choice.

Don’t get me wrong, the ActiveHybrid 5 is quite possibly the most impressive hybrid we've driven, but it’s more than likely you’ll be buying one because what it says about you rather than what it may do (for better or worse) to the environment.