All that glitters is not gold: an adage that might well be applied to the new Porsche Cayenne S Hybrid's fuel economy figure.
At first glance it looks impressive in the extreme: who wouldn't be swayed by a full 89mpg? But in light of some test drives it may seem that the European fuel economy algorithm has been heavily slanted towards plug-in hybrids.
Indeed, a brief perusal of the car's basic stats suggests that mpg figure might be rather hard to replicate in the real world: the 3.0 litre petrol engine mated to the electric powertrain delivers a decent 416bhp, while the whole beast weighs in at a hefty 2.3 tonnes; the sort of set-up that will soon get you on first-name terms with your local petrol station staff.
A perennial favourite
While I wasn't overly impressed by the first generation of Porsche 4x4s, the sales results in Britain and globally speak for themselves: the German automaker's shareholders must be very fond of the top brass who suggested Porsche enter the SUV market back in 2002.
Improved appearance
But this latest generation of Cayennes does address one of my main gripes with the first models: that they weren’t very pretty. This hybrid looks a lot less like the design team's efforts were dictated by the mechanics of the car. Although the hybrid 'green hue' design cues on the badge, callipers and instrument dial needles may not be to everyone's taste, the overall look is worthy of the firm that brought us the 911.
Fanciful performance figures?
And if we set aside any issues with the fuel economy figures for a moment, we might let ourselves be enamoured by the sheer pace of the machine – at least on paper. The sales literature says it can hit 60mph in 5.9 seconds and achieve a top speed of 151mph. But some behind-the-wheel reviews suggest these figures are a little fanciful. Some motoring journalists report that the 2.3 tonne Porsche does not feel like the most agile of SUVs.
Electrifying mpg figure?
Naturally, the battery should be charged for forays into urban settings and you would expect that to negatively impact the car's mpg figure. But some have been surprised to see it dip so low – around the early-20s mark in some tests. And even without charge mode on, this figure has been reported to only rise to below 30mpg. That's in stark contrast to the 89mpg highlighted in the brochure. In terms of fuel economy, the hybrid appears to be a worse proposition than a diesel version of the Cayenne.
Lurching around the city
The switch between electric-only and petrol is reputed to be a smooth enough experience. But some journalists have not said the same of the 'e-mode', which is apparently somewhat jerky with light throttle use. This might make city driving a 'lurchy' affair in all-electric mode. For the sake of a smooth ride you might end up using the petrol setting for urban drives – which could make you wonder why you bought a hybrid in the first place, especially if it cost you more than £60,000.
Verdict
In summary, while the Cayenne S has won points for exterior and interior styling – and being impressively roomy – it does appear to fall down due to lack of refinement in e-mode and the arguably unrealistic fuel economy figure. Given those latter two negatives, some have suggested spending the 60k on a diesel Cayenne instead.
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