When we say aerodynamics plays a very important roll in energy efficiency, especially for EVs, we mean it. We have even written a very good article about that a while ago. Air resistance can really decrease the range. In highway speeds even more than in urban traffic, where the electric motor just has to deal with weight, mostly. Nextmove, an electric car rental company from Germany, tried to show that with two very interesting tests. But there were problems...
The first one involved the Aero Wheel covers, which some rumors stated could increase range in about 10 percent. The team of Nextmove chose a 94 km (58.4 miles) route at A9, A14, and A38 around Leipzig, in Germany.
Some parameters have been established, such as a constant speed of 150 km/h (93.2 mi), 18-inch wheels with summer tires, chill mode and the most efficient driving possible.
Three Tesla Model 3 units were used to do three laps each. And here is where problems start: all of them were Long Range derivatives, but one of them was an AWD. Hence, heavier than the other two. But it gets worse: one of the RWD units had a lower suspension.
Two of the vehicles had two laps with the Aero Wheel caps and the last one without it. We don’t know which. One of them kept the Aero Wheel covers all the time as a reference. We also do not know which one. And that makes things very complicated.
Did Nextmove testers use only the numbers of each car to have a reference? Or else, did the energy consumption in each lap, for each car, get compared to the same vehicle’s lap without them? That would be the right thing to do. And we have reasons to believe that this was not the case.
The video presents a single number for both cars. The ones without Aero Wheel covers would have a 312 km (193.9 mi) range, while the Model 3 with them would achieve a 320 km (199 mi) range. A 2.6 percent increase.
The deal is that the lower RWD would save more energy than the regular RWD due to its smaller frontal area. Their numbers are certainly different. As the second test – done one week later – proves.
First, Nextmove testers put the lower RWD car against a car with an AWD Model 3 with regular suspension, both with 18-inch wheels and winter tires. Wrong, guys: it should be compared to another RWD unit.
The testers apparently realize that and put the regular RWD Model 3 in the second part of the video. They also change the winter tires for summer tires. And here another matter arises.
The summer tires made the cars present a 1 km (0.6 mi) difference on the first test and now also on the second one. The testers believe that happened due to the fact that one set was brand new, while the other two already had 10,000 km (6,213 mi) on their shoulders.
The question is: why not use similar tires in order not to have that difference? Low budget? The testers claim to have corrected that, but we cannot be sure without objective data.
If the tires did not put any sort of distortion to the tests, the conclusion is that the RWD Model 3 with a lower suspension is around 7 percent more efficient than the regular RWD Model 3. And 11 percent more efficient than the AWD Tesla with a standard suspension.
We would like to see these tests performed again, but at the Nardò circuit or any other similar track, with no traffic influence. With exactly the same cars, tires, wheels and no differences in distance whatsoever. That would lead us to less debatable results.
Anyway, Nextmove’s tests help to show how aerodynamics are a stepping stone for better EVs. If their numbers were impeccable, we could say an EV could get 10 percent more range basically with changes in air resistance.
That can be the difference in reaching the closest recharging point or having to call the tow truck. All hail cameras instead of rear-view mirrors and pop-out door handles!