Published on May 30th, 2019 | by Maarten Vinkhuyzen0
Jaguar I-PACE, Audi e-tron, Mercedes EQC — Electric Autobahn Range Disasters
May 30th, 2019 by Maarten Vinkhuyzen
The entrance of the Model S in Germany was considered a failure about 5 years ago. Autos of this class were expected to be “Autobahn capable,” which in Germany translates to driving for 3 hours at 130 mph. Of course, nobody ever does it, beside car magazine journalists testing their (and the cars’) endurance while driving in the middle of the night. In day time there is far too much traffic to do stupid things like that.
It was the lack of range at those high speeds that doomed the Model S in Germany. The increasing resistance of the air is what is the biggest energy hog at high speeds. While the Model S has an excellent aerodynamic profile, the battery storage was just not big enough to have the range at high speeds that was expected from vehicles at this price class in Germany.
While the original Model S85 was not considered “Autobahn fähig” (highway capable) with an EPA rating of 265 miles (426 km), the current S100D has an EPA rating of 370 miles (595 km), probably just enough to be acceptable to snobbish German car journalists. The new range translates to a guestimated 2 hours at 100 mph (160 km/h). There have been some changes on the Model S in recent years, both in the capacity of the cars and the expectations of the public.
Now these journalists have the difficult task of being exalted about the new entrants in the luxury electric car market, the Jaguar I-PACE (EPA 234 miles / 377 km), the Audi e-tron (EPA 204 miles / 328 km), and the Mercedes EQC (EPA ~210–225 miles / 338–362 km). This is considerably less than the Model S85, a car with a far better aerodynamic profile. (Cd 0.29 for I-PACE, Cd 0.28 for e-tron and EQC, Cd 0.24 for Model S). These higher Cd values are a bit of a problem. With higher speeds, the car needs more power to overcome the air resistance. The higher the Cd value, the more power is needed for every extra mile per hour.
In the case of Autobahn range, the higher the Cd value, the faster the range decreases with higher speeds. The EPA rating is a mixture of urban driving, outside city (45 mph, or 72 km/h) driving, and a bit of highway driving. It is already too optimistic for pure American highway driving. I have not seen numbers for German Autobahn driving, but they will not be pretty. The range will drop with something like 40% when increasing the speed from 75 mph to 100 mph (121–161 km/h).
These three new competitors in the high-end luxury segment will have exhausted their battery after about 1 hour of driving at 100 mph (161 km/h). But these are not despised American intruders that need to be put in their place. These are the pride of the German (and British) car industry. Loyalty dictates a loving review.
I am glad I am not a German car journalist. What is there to write about these cars that have about half the Autobahn range of the barely good enough Teslas? Perhaps it is best not to mention the Autobahn at all, or hype the coming abundance of ultrafast charging stations along those Autobahns.
The conclusion is simple — this first generation of Tesla competitors need some work on efficiency and aerodynamics, and they need a lot more battery storage. The 2 hours at 100 mph for the Tesla Model S100D is using 100% of its battery capacity. For real driving, you want to do this with the battery between 80% SoC and 10% SoC, or just using 70% of total battery capacity. For Tesla, that is an increase of nearly 50% of its current biggest battery, for those competitors, it is a 200% (or triple) increase of capacity.