Real world range

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What is everyone using to get their quoted mi/kWh numbers?

I have my car set to reset the values for every trip and was looking at the reported mi/kWh average for the trip but it doesn't seem right:

Reported trip efficiency: 3.6 mi/kWh
Reported trip distance: 14 mi
Battery used: 11% -> 28.9 kWh * 11% = 3.179 kWh
14 mi / 3.179 kWh = 4.4 mi/kWh

Am I missing something?
 
GvilleGuy said:
You're not missing anything - the Mini's range computer is simply too conservative. It will rarely show you the efficiency you are really getting. Manual calculation is the way to go if you are on a road trip where distance matters.
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Well that's just dumb. Average trip efficiency isn't an estimate like predicted range, it's a simple calculation so it should be pretty exact.

I wonder if it's a hold over from how they calculated average mpg in the ICE cars or if they actually put some scale factor to make it more conservative?
 
My opinion: There are just so many factors that can impact your range at any given moment, Mini doesn't want to build all of those variables into its calculations - Speed, temperature, dew point, elevation changes, wind. But I think they went too conservative. It would be great if they would add a "road trip algorithm" option that would estimate range based on miles driven on the road trip. So, if you are 30 miles in, do the math based on those 30 miles of driving conditions and show the estimated range for that. "Based on your last 30 miles driven, assuming conditions do not change, you should have X miles of range remaining." The main gotcha I can think of would be someone driving up into a mountain range, or a dramatic change in wind or temperature.
 
GvilleGuy said:
It would be great if they would add a "road trip algorithm" option that would estimate range based on miles driven on the road trip. So, if you are 30 miles in, do the math based on those 30 miles of driving conditions and show the estimated range for that. "Based on your last 30 miles driven, assuming conditions do not change, you should have X miles of range remaining."
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I think it already does this--you just have to drive long enough for that to happen.

When you start a new trip, the range is calculated from some aggressively conservative consumption value. After driving at a steady state for a longer distance/time (like during a road trip), the projected range will creep up to approach a value closer to your own calculations.
 
GvilleGuy said:
My opinion: There are just so many factors that can impact your range at any given moment, Mini doesn't want to build all of those variables into its calculations - Speed, temperature, dew point, elevation changes, wind. But I think they went too conservative. It would be great if they would add a "road trip algorithm" option that would estimate range based on miles driven on the road trip. So, if you are 30 miles in, do the math based on those 30 miles of driving conditions and show the estimated range for that. "Based on your last 30 miles driven, assuming conditions do not change, you should have X miles of range remaining." The main gotcha I can think of would be someone driving up into a mountain range, or a dramatic change in wind or temperature.
Click to expand...

My hope is that sooner rather than later, we can start to treat the GoM the same way most people treat the equally horrible range estimates in their ICE cars: just ignore it!

When chargers are plentiful enough, an EV driver should just be able to casually monitor the battery percentage and decide to stop at a charger when at 10-20% just like with a gas gauge reaching 1/4-1/8 tank... Or empty if you like to live on the edge lol
 
@Carsten Haase - absolutely! The best thing you can do is set the display to percentage and forget the GOM, though the UI is a little messy in our Minis (miles/percentage/temperature are easy to confuse, while the 8 segment charge display lacks granularity).

I wish automakers would abandon the skeuomorphic "gas tank" graphics and prominently display the battery percentage with a simple battery icon. Just like a phone or tablet. Easy.

Tesla is doing this already, and Hyundai's new Ioniq 5 follows suit.
tesla-model-3-suprcharger-update.jpg
 
I am starting to think that the GOM is calculated using the energy used only, and not counting any regen. The reason for this is that a while ago, I noticed that (in the old app), my consumption was 18kWh/100k, but I also had 6kWh/100k of regen. This equates to near my basic 12.5kWh/100k long term average. Maybe they just use the last trip *used* figure. 28.9 / 18 = 1.6 = 160km range. Hmmm. Again today, after fully charging, I got, wait for it, 160km range. Now I would usually expect 240km from a charge, even in our hideously cold winters in Oz. I happened to look at just the right time, I had done 79.4km (call it 80k between friends), and had 66% battery left. That would indicate 240km full range (80/ (1/3) = 80 * 3). So remaining = 160km. The GOM said exactly 100. So I started off with the GOM being 50% out (240/160 - 1), and after 1/3 of the charge it rose to 60% out (160/100 - 1).

Curiously, if I used the non regen power use (18kWh/100k), I would get 96km range with 1/3 used. Hmmm. Coincidence? Maybe the bug is just a really silly error in the algorithm which doesn't take into account any regen and hence doesn't use the *actual* energy used. This would represent the range if you could disable all regen. If this is true, it is quite sloppy programming, and renders the GOM useless as it is designed to give the wrong, under quoted range. Hopefully I am wrong, but........
 
Here's a fun GOM anecdote:
On my drive home from work today, I started at 68% with a predicted 63mi of range.
16.1mi and 10% later, I arrived home with 64mi of predicted range left!

Sure, it was slightly downhill but 500ft over 16mi isn't an excuse for that poor of a prediction. I wasn't exactly flooring it on the previous trip to work either with an efficiency of 4.3 mi/kWh
 
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