It's all about CAFE standards, right? Federal corporate average fuel economy legislation means every car maker wanting the privilege of selling its wares in the States will have to comply. Hence all the hybrids, EVs, diesels, etc. But not so fast... and maybe not so cynical.
Here's the thing: Porsche customers are asking for hybrids. As unsure as the company is of a business case for diesel Cayennes, it's certain enough to produce a hybrid Cayenne that goes on sale in North America in spring 2010 with a ballpark price of around $70,000. Porsche will also make noises about "social responsibility" but, hey, whatever gets its engineers through the night when they are dreaming about what to do with all those dead nickel metal hydride battery packs. Perhaps they might also take into account the working conditions of miners and what impact a nickel mine has on its surroundings. But at some point in the final shakedown, the result is less fuel being used and less emissions from vehicles.
Because it's made by Porsche, the Cayenne S Hybrid (the S denotes the same trim and comparable power levels to a conventional Cayenne S) bristles with smart technology, including an eight-speed automatic transmission-not a CVT like so many boring hybrids. This is certainly not a case of paying Toyota a licensing fee and then adapting its system. For instance, the Lexus RX hybrid uses an electric motor to power its rear wheels. Porsche's electric motor adds 38 kilowatts of heft to a 333-hp 3.0-liter V6 (sourced from Audi and utilizing direct fuel injection) which is then sent to all four wheels. Hence the lack of lithium ion batteries. They're OK for puny little 17-kilowatt motors, but Porsche has to have the punch from a nickel metal hydride pack.
Altogether, the system puts out 374 hp and a substantial 406 lb-ft of torque, good enough for zero to 60 mph in 6.5 seconds. Top speed is 149 mph. Yet Porsche says fuel savings are 50 percent over a gasoline-powered V6 Cayenne. When driving in the real world, the combustion engine is only working for about 44 percent of the time. Brake regeneration takes up 12 percent, electric-only locomotion is 26 percent, and the stop/start feature accounts for the remaining 18 percent. Average consumption works out to around 27 mpg, with a range of 680 miles.
It works. Over an admittedly short test distance, the Cayenne Hybrid is an extremely pleasant thing to pedal. Trying to hit that magic 680 number should feel like no chore whatsoever. It has all the capability and class expected from a high-end German SUV (the prototype used in this test is worth about one million euros; that's pretty high-end).
Just like the diesel version, this one is serene, changing gears as if by magic. It can run up to 32 mph in electric-only mode. On downhill stretches, the Cayenne hybrid has a freewheeling function: the engine turns off, ready to re-ignite at the touch of an accelerator. Same story at traffic lights and other stop/go situations. This function operates with the same ninja-like subtle efficiency as the gearbox. And the brakes do that usual hybrid regeneration thing. The brake pedal feels super-sharp the first couple of presses, but it's easy to get used to after a few miles. Which is more than can be said of the steering. Unlike the rest of the Cayenne range, this is electrically assisted. It doesn't have quite the feel or weight expected from this marque.