Out of Spec Reviews ran the new Porsche Cayenne Electric against a Rivian R1S in a 70 mph highway range test, and the result was closer than the battery sizes suggest. The Cayenne carries 108 kilowatt hours usable out of 113 gross. The R1S dual motor Max Pack in the test carries roughly 140. The Porsche managed 344.7 miles before it stopped holding 70 mph, at 316 watt hours per mile. The Rivian's display showed 358.3 miles, which the channel corrects to around 356 once the speedometer difference is accounted for. For most of the run the two cars sat within one percent of each other on state of charge, which the host says he had never seen in a comparison before.
Range tests are usually settled by pack size, which is what makes this one worth reading twice. The Cayenne was ordered with Porsche's range package, which the video explains allows a no cost drop to 20 inch wheels, below the 21 inch standard fitment. Set that against the Cayenne Electric Turbo carwow tested in the UK, also covered on this site today, which was averaging around 2.4 miles per kilowatt hour on 22 inch wheels. The Out of Spec car returned better than three miles per kilowatt hour. Two cars from the same family, a spread of roughly 25 percent in efficiency, decided largely by wheels and options rather than by anything in the powertrain. For anyone actually ordering a Cayenne Electric, that is the more useful finding here, and unlike most range advice it costs nothing to act on.
The conditions were about as controlled as a public road test gets. The channel reports around 81 degrees Fahrenheit, very little wind, cruise set to 70 mph by GPS, climate limited to the driver and every other load switched off, with both cars run until they could no longer hold speed. Out of Spec is upfront that the Rivian was not a fresh example, noting it had covered 27,000 miles and pulled 138 kilowatt hours against a previous best of 144, which the host puts at around four percent degradation and estimates would have placed a new example nearer 370 miles. Charging is where the video sees the real separation, quoting the Cayenne at a 400 kilowatt peak and roughly 15 minutes from 10 to 80 percent. On towing the two are almost identical, at 7,713 pounds for the Porsche and 7,700 for the Rivian.
Both cars were configured for maximum efficiency. The video explains that the Cayenne has no eco or range driving mode, so the setup amounted to normal chassis mode, suspension dropped to its lowest ride height, soft damping, the synthetic drive sound switched off and automatic recuperation selected for more coasting. The test car was ordered without a sunroof, without rear axle steering and without a tow package. The Rivian ran its all purpose mode, which the channel says disconnects the rear axle and drives the front wheels only at highway speed. What happens at the bottom of the pack drew the host's attention. He reports the Cayenne reaching turtle mode at one percent and 342 miles, continuing past a zero percent indication, then cutting its contactors and allowing a limited number of manual restarts, each giving slightly less distance than the last. The Rivian lost its 12 volt system when it stopped and had to be jump started before it would accept a charge.
Bottom line: Porsche won the engineering argument and Rivian won the test. Getting 345 miles out of 108 kilowatt hours in an SUV this size is the more impressive number, and it is the one that pays off at every stop, because a small pack refilled at 400 kilowatts is a shorter break than a large pack refilled slowly. If you road trip, the Cayenne is the better tool. If you tow, or you simply want range you never have to think about, the Rivian's extra 30 kilowatt hours still counts for something.
Commentary on a third-party video. Figures and claims are as presented in the source and have not been independently verified. Spotted an error? Tell us and we will correct it.