All of which results in the headline figures of 34.4mpg and 193g/km.
What’s it like?
Extremely effective. The real benefit to the hybrid system, apart from the fuel savings, is the refinement. Around town the system regularly propels the Cayenne on pure electric power, resulting in eerily silent progress, and though (as with all current hybrid systems) you have to be extremely careful on the throttle and be willing to infuriate following traffic if you want to pull away from a standstill without triggering the V6 motor, it is nonetheless quite possible to cover a useful urban distance without ever using any petrol.
Driving normally will result in regular interaction between the petrol and electric motors, and it’s impressive that the transition between the two is barely noticeable. There’s ample flexibility to make the Hybrid an enjoyable and relaxing urban and motorway tool, thanks as much to the eight-speed gearbox as the powerful motor.
The Porsche hybrid system also boasts an extra element of technical wizardry, in that it has the potential to disengage its combustion engine and 'sail' at anything up to 97mph.
In practice, this means that taking your foot of the throttle and simply allowing the car to roll along will trigger the separator clutch and the V6 motor will stop running. Because there is no engine drag causing resistance, and because in this state the electric motor delivers a stream of power, the Cayenne can run for good distances without using its petrol engine. It can feel slightly disconcerting initially, but with familiarity this becomes one of the most useful abilities the Cayenne hybrid offers.
The standard steel springs on the hybrid don’t manage to restrain body roll as well as the more sophisticated air suspension (which is available as a £2330 option), with body float noticeable over undulating surfaces. But the suspension still does a decent job of absorbing most interruptions in the road surface.
Ask the Hybrid to deliver all its performance potential and the supercharged V6 can sound strained but the scenery will be passing you by fast enough that engine noise won’t be of much concern. The Hybrid may lack some of the handling finesse and all of the drama of the Turbo model, but there is no doubting that it’s worthy of the ‘S’ on the end of its name.
Should I buy one?
If you regularly drive around town and yet want a premium SUV, then yes – the Cayenne could be your ideal mode of transport. But think carefully about the 3.0-litre V6 turbodiesel before handing over the cash needed for a Hybrid.
There is no doubt that the Hybrid offers much more impressive performance than the diesel Cayenne, and yet isn’t far off that more conventional model’s claimed 38.2mpg. But despite the hybrid’s outstanding combination of refinement and pace, it may struggle to justify the extra £13,000 you’ll have to shell out if you want the petrol/electric Cayenne instead of its oil-burning sibling.