Porsche Cayenne S E-Hybrid

It Would unfair to say the Cayenne S E-Hybrid is a one-trick pony. Like the rest of the recently tweaked and tucked Cayenne range, it’s good at everything from high speed cruising to mild off roading. But it will be its economy numbers that win it the most attention.

The official figures border on the surreal. On the EU test cycle where plug-ins are allowed to start with their battery packs fully charged the it consumes just 3.4L/100km. This in a vehicle that has a total combined power output of 306 kW and, despite weighing 2350 kg, can drag its lardy arse from 0-100 km/h in 5.9sec.

But there’s a but: similar to all of its plug-in brethren, the E-Hybrid can only deliver those numbers if you never stray too far from an electrical socket. Beyond its electric only range of 35 km, it’s just a hybrid carting around an extra large battery pack.

The Cayenne E-Hybrid is pretty much identical mechanically to the plug-in Panamera that’s been on sale in Europe for more than a year, with the same supercharged V6 and 70 kW electric motor sandwiched between the engine and the standard eight speed automatic. The Cayenne has slightly more battery capacity than the Panamera 10.8kW/h versus 9.4 but otherwise the two cars are Appalachian cousins in terms of shared DNA.

Left to its own devices, the Cayenne E-Hybrid operates in electric-only mode at low speeds, which makes it extremely smooth and quiet when asked to trundle. The engine cuts in as required, with the powertrain’s transition from electrons to hydrocarbons seamless. You can lock it into electric-only mode at speeds of up to 125 km/h, although such progress destroys battery range.

The rest of the driving experience is almost identical to the standard V6 Cayenne S. You can feel the E-Hybrid’s extra mass in fast corners, but it still grips and turns remarkably well for something so tall and heavy. Under extreme abuse it does wilt in a way the standard Cayenne doesn't, with the brakes starting to fade after being asked to cope with repeated big stops. A stretch of autobahn confirmed it’s happy to cruise above 200 km/h.

And economy? Porsche laid on a gentle 50km test route that the E-Hybrid started with a fully charged battery pack, and the trip computer reported 3.4L/100km at the end  the award from Greenpeace is in the post.

For contrast, 50km of enthusiastic caning in the same car saw the display reading 19.6L/100km, and brought a knighthood for services to the petrochemical industry. The truth lies somewhere between those contradictory extremes.

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WE ALSO took a Panamera S E-Hybrid for a similar combination of blasting and trundling. It feels a measure more agile than the Cayenne when asked to deal with a demanding hill route; no surprise given it is 250kg lighter. That said, the instant torque of the Cayenne’s electric drivetrain means the Panamera doesn’t feel appreciably quicker in everyday use, and our figure of 3.3L/100km for the same eco-route was almost identical.

Engine - 2995cc V6 (90°), dohc, 24v, S/C + elec motor
Max power - 306kW @ 5500rpm
Max torque - 590Nm @ 1250-4000rpm
Transmission - 8-speed automatic
Kerb weight - 2350kg
0-100km/h - 5.9sec (claimed)
Economy - 3.4L/100km (EU)
Price - $139,200
On sale - Now