2010 BMW ActiveHybrid 7

A battery pack clutters the boot of BMW's big ActiveHybrid 7 but is it worth this obvious flaw?

BMW believe the ActiveHybrid 7 is ideally suited to the Arabian climate, with the lithium-ion battery being kept nice and cool in the boot of the car.

Let's be honest, the BMW ActiveHybrid 7 is no Toyota Prius. You won't see well-meaning celebrities wearing their 4.7L/100km fuel economy on their sleeve when they are spotted by the paparazzi filling their ActiveHybrid 7s. But that's not to say it is devoid of conscience. The ActiveHybrid 7 offers a combined fuel economy of 9.4L/100km, an improvement on the 11.4L/100km of the standard 7 series and excellent economy for a vehicle that, with the added 100kg of the electric motor and lithium-ion battery, tips the scales at 2,045kg.

The near-instant stop-start function automatically cuts out the engine when the car comes to a complete halt and starts it up again in a millisecond, saving fuel and cutting emissions. It is a mild hybrid - the electric motor assists the petrol engine rather than having the ability to work as a fully electric car. When I drove the ActiveHybrid 7 in Germany, not only did I get to try out the car on country roads, narrow, quaint streets and an autobahn but I also attended a workshop where the car was explained to me in great detail, everything from how the engine worked to the practical stuff, such as a slight loss of boot space because of the placement of the hybrid components.

"The hybrid was always going to be a question of trade-offs," says Uwe Greiner, product manager for the 7 Series. "But we have created a favourable compromise." The compromise involved losing 40L of boot space to make way for the battery and electric motor, but the boot remains roomy at 300L. The ubiquitous golf bag comparison came out again - always a popular measure of boot space for high-end cars - with Greiner saying the boot can still hold four golf bags and, for further target market fun, the rear seats can be partitioned to make way for a pair of skis.

"The lithium-ion battery is in the trunk but it is very compact and putting it in the trunk helps to keep the driving dynamics so it is nicely balanced between the front and back axles," says Greiner. He is dead right - the car corners magnificently, there is no trace of over- or understeer and the suspension is incredibly comfortable even on old cobbled German streets, so the UAE speed bumps are unlikely to trouble the springs and struts of the ActiveHybrid 7.

For consumers who are worried about driving a car with a lithium-ion battery in the Arabian heat, Dr Stefan Riederer, an engineer and aerodynamics expert for BMW, is quick to reassure potential UAE buyers. It turns out the rearward position of the battery is rather useful in this regard. "The cooler temperature at the rear of the car means the battery life will be extended," Riederer says. This is especially important for consumer confidence as BMW guarantees the battery for the life of the car.

As well as the usual myriad airbags, safety is another consideration when it comes to the placement of the battery. "In an accident, the battery is safer in the rear of the car," says Riederer. "In a crash from behind, the rear axle protects the battery and the rear axle and rear wheels absorb the impact and the battery should not be damaged." But it will be the driving experience that will truly sell this car in the Middle East, where the price of fuel is still not a huge issue with many buyers, especially at the 7 Series end of the market. Performance-wise, it is very impressive with 700Nm of torque, and it does the sprint to 100kph in 4.9 seconds.

On the autobahns around Munich, it hit 180kph with no trouble at all and the gear changes are so smooth they pretty much go unnoticed. The impressive torque doesn't hit you in the face but it powers the car along effectively - there is absolutely no discernible difference in performance from the driver's point of view compared to the regular 7 Series. Cosmetically, the ActiveHybrid 7 looks much like a standard 7 Series but with added design touches, such a BMW badge on the C-pillar, an ActiveHybrid 7 badge on the rear lid, special light alloy wheels designed to look like turbine blades, a new instrument panel and ActiveHybrid 7 branding on the door sills.

The expected 7 Series luxuries are all in place, such as the air-conditioned seats, an easy-to-use sat nav, wood panelling, individually reclining rear seats that are reminiscent of an aeroplane's business class, entertainment systems for passengers and an air-conditioning unit that can be operated remotely before you get in the car. All these plush touches, along with the impressive performance and über-quiet ride, will have appeal in the Middle East, where the 7 Series with a petrol engine has done rather well for BMW.

Along with the ActiveHybrid X6, BMW has debuted the ActiveHybrid 7 in the Middle East at the Dubai International Motor Show. [e-mail]