The optional "virtual exterior mirrors" improve the crossover's aerodynamic efficiency to achieve a drag coefficient of only 0.28.
In the build-up to the world reveal of the production-ready E-Tron, Audi has been kind enough to share a great amount of details about its fully electric crossover, including some of the juicy specs. In the most recent episode released today, the peeps from Ingolstadt are happy to talk about how they were able to achieve a drag coefficient of only 0.28.
While that number might not be very impressive compared to the Volkswagen XL1’s Cd of 0.189 or the Mercedes CLA 180 BlueEfficiency’s 0.22, let’s keep in mind the E-Tron is a tall vehicle as every other crossover out there. Having spent more than 1,000 hours in the “world’s quietest vehicle wind tunnel,” Audi’s zero-emissions CUV came out with a remarkably low drag coefficient following numerous tweaks to create a sleek body and consequently boost aero.
A crucial role was played by what Audi refers to as “virtual exterior mirrors.” Set to be offered as optional equipment (in countries where these will be legal), these will in fact be cameras to replace the conventional side mirrors. When equipped, the E-Tron’s width is reduced by a significant 15 centimeters (5.9 inches) and aside from reducing drag, these also diminish wind noise.
The footage grabbed by the cameras is shown on OLED displays located between the instrument cluster and the doors. Audi points out drivers will get to pick from three different viewing modes, depending on the driving situation: highway driving, turning, and parking.
But there’s more to the E-Tron’s aero story than its tiny mirror-replacing cameras. For example, the standard air suspension with adjustable damping lowers the vehicle’s body by up to 26 millimeters (1 inch) at speeds above 74.6 mph (120 kph) to reduce drag. In addition, the underbody is fully enclosed while both the front and rear areas are entirely paneled.
Also contributing to a lower drag is the active cool-air inlet with two electrically operated louvers lurking from behind the corporate singleframe Audi grille. The side air inlets at the front also feature extra ducts to optimize airflow. Even the 19-inch wheels have been aerodynamically tweaked by adopting a flatter design than conventional alloys. Ultra-low rolling resistance tires measuring 255/55 wrap those wheels and feature special tire sidewalls with negative lettering instead of raised to serve as yet another measure to further reduce drag.
As a result of these multiple aero-focused enhancements to squeeze every last drop of efficiency, the Audi E-Tron will provide a maximum range of more than 248.5 miles (400 kilometers) in the more stringent WLTP cycle. It will be possible by using a large 95-kWh lithium-ion battery pack mounted within the floor and rechargeable in just 30 minutes from a powerful 150-kW charging station.
Audi will reveal the road-going E-Tron on August 30 at the Audi Summit in Brussels, Belgium. In 2019, the more stylish E-Tron Sportback will join the company’s EV portfolio.
Gallery: 2019 Audi E-Tron aero teaser
Streamline: Audi e-tron prototype with decisive aerodynamics
- Electric car with sophisticated aerodynamics concept: drag coefficient of 0.28
- Important factor particularly on long journeys: drag
- For the first time in a volume-production car: virtual exterior mirrors as a high-end option
The better an electric car’s aerodynamics, the further it travels: With a drag coefficient of 0.28, the Audi e-tronprototype achieves a top result in the SUV segment. This figure is a decisive factor in the everyday range of more than 400 kilometers (248.5 mi) in the WLTP cycle. The virtual exterior mirrors constitute one highlight in the aerodynamics concept of the all-electric premium class model.