BMW ActiveHybrid 5

BMW is getting serious about petrol-electric power, and Auto Express was among the first to drive its ActiveHybrid 5. So can the newcomer make a solid case against the company’s impressive diesel models?

BMW has taken the 535i’s 302bhp 3.0-litre turbocharged six-cylinder engine and ZF eight-speed automatic transmission and combined them with a 54bhp electric motor and lithium-ion battery pack. The result is total power output of 335bhp, and 450Nm of torque. The ActiveHybrid 5 has two drive modes: pure electric and a parallel ‘boost’ mode in which the petrol and electric motors are both in use.

Pure electric is only for slow-speed work, as the range is limited: BMW says an average speed of 22mph will allow you to travel around three miles, while the maximum speed is approximately 45mph. Any higher and the drivetrain will switch to the second mode.

The ActiveHybrid 5 swaps seamlessly between these set-ups, while there’s also a battery-recharging phase during descents and under braking. Graphics that show how well or poorly you’re doing are displayed on the iDrive screen, as well as in the centre instrument cluster.

Put the ActiveHybrid 5 in Sport+ mode and you’ll access the total power output. That gives a claimed 0-62mph time of a mere 5.9 seconds, matching the petrol 535i SE’s acceleration.

In normal mode, the ActiveHybrid 5 isn’t quite as rapid as there’s no extra battery power – we would estimate the 0-62mph time to be around 7.5 seconds. To maximise economy, the ActiveHybrid 5 debuts BMW’s Intelligent Energy Management software as part of the optional Navigation Professional system. This reads the road ahead and reacts accordingly, selecting which 
mode will be most efficient for the cleanest driving possible.

The hybrid claims to emit 16 per cent less CO2 than the 535i SE and improve economy by around 12 per cent. This means emissions as low as 149g/km with average returns of up to 44mpg when driving in the most frugal EcoPro mode.

Efficiency also depends on which wheels and tyres you go for. The ActiveHybrid 5 comes with 17-inch low-resistance tyres as standard, but our test car featured optional 18-inch Streamline alloy wheels. On the larger wheels over Portugal’s undulating coastal terrain, the best we achieved was 30.1mpg. In a 535d diesel we would expect to be getting nearer 40mpg in regular driving.

There’s another extra cost – reduced practicality. The lithium-ion battery pack is positioned over the rear axle, adding 140kg to the weight of the 5 Series. Unfortunately, the pack reduces luggage space to 375 litres – a drop of 145 litres. On top of this, the rear seats no longer fold down, as the battery pack nestles between the cargo area and the bench.

The other major challenge is the price: the ActiveHybrid 5 faces an uphill battle as, at £46,860, it costs six per cent more than the 535d and 20 per cent more than the 535i SE on which it’s based. By comparison the 535d is £44,290, and it’s faster in the real world and more economical, too.

Even so, the ActiveHybrid 5 is well executed with typical BMW attention to detail. It provides the best hybrid experience so far from Germany’s premium brands.