How range varies with driving speed

[user 2619]

I have an Oct 2019 eGolf.
I am trying to find how the miles per kWh varies with speed. I have contacted VW customer services and the are unable to supply the data.
I realise driving technique and settings (air con, wipers heated seat etc) will all have an effect, however if those factors are all the same or off, has anyone come across the data as to how the m/kWh or range varies with speed of travel?
If so, can someone point me in the correct direction.
Many thanks.
RB

 

[f1geek]

The faster you go above 40 mph, the lower your efficiency. I bet if you are on a level road, at 55 mph you should be able to get 4 miles/kWh or better. At 70 mph, I'm guessing (I rarely drive faster than 63 mph) you get something closer to 3 miles/kWh. Above 70 mph and expect less than 3 mi/kWh. Like you said, all power draws have an impact on efficiency, but high speed has a major impact. Best of luck!

 

[cctop]

Take a look at this thread for experimental numbers for the 2015 eGolf:

https://www.myvwegolf.com/forum/viewtopic.php?f=11&t=927

Here's a graph of the data in the thread which shows that the 2015 eGolf is most efficient at about 18mph, energy usage increases fairly linearly, and going 70mph takes about 50% more energy than going 50mph:

https://imgur.com/GlvFfpM

Last, I've been driving a 2019 SE for about 9 months. I don't have any numbers to share, but compared to my 2016 SE my impression is that the 2019 is about 10% more efficient at highway speeds and 10% less efficient at city speeds.

 

[f1geek]

Aerodynamic drag varies as a function of the square of the speed, and you can see the energy usage goes up more at higher speeds. 80 mph really sucks down the electrons.

Because the 2019 lacks the active lower grille shutters (open grill all the time), efficiency on the highway is lower as compared to a 2017 due to more drag.