The Cayenne is a spicy-hot mix of luxury, off-road ability, and sports-car performance—just what you would expect in a Porsche SUV.
The base model has a 300-hp V-6; the S makes 420 hp, the GTS makes 440. Both have a twin-turbo V-6. A hybrid also is offered. All models feature eight-speed automatics and all-wheel drive. The Cayenne is easy to hustle around curves and is equally ready for family duty.
A stop-sale on 2015-2016 diesel models is in place until further notice due to EPA violations.
When we climbed into this plug-in hybrid at our Ann Arbor offices and set out on a 50-mile drive home at rush hour, the instrument panel showed a full battery charge and an all-electric range of 14 miles. That would be in what Porsche calls E-Power mode, the default at start-up and also selectable via a console button. This Cayenne S hadn’t been plugged in, though. The previous driver had pressed the E-Charge button, adjacent to the E-Power one, on his commute that morning. This kept the engine running to maximize recharge, disabling the stop-start function and running the generator continuously. Porsche says charging the 10.8-kWh lithium-ion battery pack this way reduces fuel economy by about 20 percent, but only during the 20 or so miles it takes to pack the cells full of energy.
After that, the car operates in ordinary hybrid mode, the electronics assessing the driver’s demands and the batteries’ state of charge to decide whether to use the 333-hp 3.0-liter supercharged V-6, the 95-hp electric motor, or both. We traveled just over 15 miles on battery alone, through heavy congestion in town and then about 10 miles of interstate—the electric motor by itself provided plenty of thrust to merge onto the freeway from an uphill ramp at more than 65 mph (stated top speed in this mode is 78) without engaging the engine. If we’d wanted or needed to, even in E-Power mode, pressing the pedal through a stiff detent would fire up the V-6 and bring the full combined output of 416 horsepower to bear, but there was no call for that on the clogged artery that is US-23 at 4:30 p.m.
When the batteries were depleted, we were on open highway, where hybrids rarely hold any fuel-economy advantage. Pressing the E-Charge button and moving along at 70 to 80 mph, we watched the battery-range indicator rise steadily. With such a strong engine, there was no discernible loss of performance from the added load to recharge. The dash showed 14 miles of battery range again just as we exited the freeway into more stop-and-go congestion, so a tap of the E-Power button put us back in all-electric operation. Quiet, strong enough for these conditions, and virtuously free of tailpipe emissions, the electric motor took us 12 more miles home, showing 2 miles of range remaining. All told, then, we’d driven 27 out of the 50.4 miles on battery alone. Other hybrids, like the Chevy Volt, also let the driver choose when and where to deploy battery-only mode, a particular advantage in dense urban areas of the world where regulators restrict access to combat smog and carbon emissions. Few hybrids, though, combine a big battery pack and a system capable of recharging it to full capacity mid-commute.
In theory, we’d have plugged it in overnight and the standard 3.6-kW onboard charger would replenish the battery pack in about three hours. (A faster 7.2-kW unit is offered, but our test car lacked that $840 option.) Theory gave way to the reality that we needed to go other places that evening and so we employed the E-Charge mode again, arriving home with 9 miles of electric range showing. Late at night, it seemed like a hassle to drag out the cord and plug it in overnight just to get a few more miles, so we didn’t. Research shows this attitude is common among owners of plug-in hybrids. The next night we did plug in, mostly because this is a road test and we felt obligated. The ability to drive on juice from the grid is what separates this new model from the previous Cayenne Hybrid, a traditional hybrid with a relatively tiny 1.7-kWh nickel-metal-hydride battery pack.
The combined system output also increases by 36 horsepower, all of it attributable to the electric side. At the track, this means the E-Hybrid gets to 60 mph in 5.4 seconds, a gain of 0.3, and through the quarter-mile in 13.7 at 103, 0.6 second quicker and 6 mph faster. Our tester noted that performance fades as the charge depletes over repeated full-throttle acceleration tests, which we do routinely to determine how best to launch the car. Incidentally, 5.4 seconds to 60 mph is identical to Porsche’s claim for this model and 0.2 second shy of the carmaker’s estimate for the standard Cayenne S with a 420-hp 3.6-liter twin-turbo V-6 (we’ve not yet tested the latest Cayenne S). The new hybrid stopped from 70 mph in 176 feet, identical to its plugless predecessor, and cornered at 0.83 g.
These are good numbers, but particularly so for a 5427-pound SUV. Its dynamic properties help put the Cayenne among our favorite SUVs, and the only thing that’s really affected by hybridization is the brake feel. Porsche has done as good a job as anyone of integrating the regenerative and mechanical operations, but there’s an inherent inconsistency traceable to variations in how much regen the system needs. So the pedal feel is good, but each application can seem a little bit different than the last. It’s a nonissue if you’re not driving hard over a long stretch (or on a track), but it’s still there.
A Venn diagram mapping new-car shoppers who set out in search of a plug-in hybrid against those thinking “luxury SUV” likely would show a minuscule overlap. Porsche is the first to serve that tiny sliver of the market, but Audi, BMW, Volvo, and Bentley are coming right on its heels. It’s not that we think the high-end market is hostile to green technology (Tesla proves otherwise), but that the image of an SUV doesn’t square with the eco-elitist mind-set. It doesn’t square with the sports-car mind-set either, though, yet Porsche has made it work.
As usual with Porsche, the buy-in cost can rise steeply when you start ticking off boxes on the options list. There’s nearly $20,000 worth of extras on the $96,810 example you see here, the biggest chunks being a $4090 Premium package (panoramic sunroof, ventilated seats, etc.) and $3665 for the black leather upholstery and wrappings. Adaptive cruise control cost $2300, the infotainment package $1990, and the 20-inch RS Spyder wheels added $1560. Throw in a heated steering wheel ($275), brushed-aluminum interior trim ($995), and so on. Clearly, these are buyers for whom going green does not equate to donning a hair shirt.
The appeal of a plug-in with significant electric range is that the owner can enjoy the experience of electric driving without sacrificing the ability to make long trips. In this case, though, Porsche has rendered the plug all but superfluous. With gas prices low and living as we do in a region where much electric power still comes from coal-fired plants, neither the economic nor environmental arguments seem compelling reasons to plug in routinely. A stronger incentive is access to those premium parking spaces set aside for electric vehicles at the airport and at some workplaces and parking structures.
That leaves the “cool-technology” factor and a “save the planet for our grandkids” sense of virtue as reasons to buy. On the latter score, the E-Hybrid’s EPA combined rating of 22 mpg (they publish only combined numbers, not city/highway, for plug-ins) is a slim 2 mpg better than that of the standard Cayenne S. We saw 21 mpg in our test, a figure that might have been a little better if we’d plugged it in more often. But why?