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380 WH/MI

I have a 2018 model S 75d with 34k miles on it. I’ve been averaging mid to high 300 WH/MI and at times up to 420. Is this normal for a mix of city and highway driving? I’m driving somewhat aggressive and usually set cruise at 82. Ive also had a yellow triangle warning show a couple of times on the WH/MI gauge. Does anyone know what that warning means?
 
At 82 mph your WH/MI will be high. Air drag increases with the square of the speed. It takes energy to push the air out of the way.
The triangle means the battery is cold. That also means that energy from the battery is being used to heat the battery.
Is the cabin heater on? Energy used to heat the cabin is not available to propel the car.
 

DerbyDave

Active Member
Jul 2, 2020
2,259
1,306
Kentucky
A warning triangle is displayed temporarily in the energy information whenever something has changed. If your car is cold, and regen either has decreased, or increased from full, the warning symbol will be displayed briefly. The next change it will reappear. Same for cold battery. It comes and goes to let you know your braking or acceleration may be different.
 
If you car is sitting outside overnight, then you will see quite high Wh/mi numbers on the first drive of the day as energy is used to warm up the pack. You can reduce this by preheating the car, but that doesn't necessary reduce your total energy consumption, but makes your Wh/mi number look better as the trip display Wh/mi number only considers energy use while the car is driven, not parasitic energy consumption for such things as preconditioning. If you have the ability to charge at home, the most efficient way to preheat the battery is charging and timing your charing to end shortly before your scheduled departure.

For context, here's 5.5 years, 65k miles of real world data off of my MS90D. I think I'm base a little farther south than you, in south central Indiana, so not as cold on average but has winter trips through the NE included. While my lifetime average is right around 278 Wh/mi, you'll see some individual trip dots as high as 500 Wh/mi and other warm weather driving as low as the 240s. I don't tend to drive quite as fast as you, probably more like 73-75 on interstate, so that also influences some difference. You can clearly see the seasonal variation due to largely ambient temperature.

1636848921020.png
 
For context, here's 5.5 years, 65k miles of real world data off of my MS90D. I think I'm base a little farther south than you, in south central Indiana, so not as cold on average but has winter trips through the NE included. While my lifetime average is right around 278 Wh/mi, you'll see some individual trip dots as high as 500 Wh/mi and other warm weather driving as low as the 240s. I don't tend to drive quite as fast as you, probably more like 73-75 on interstate, so that also influences some difference. You can clearly see the seasonal variation due to largely ambient temperature.

Sorry for the newbie question, but how do you obtain the data for this?
 
Sorry for the newbie question, but how do you obtain the data for this?
For this I've gone old school ... I've used excel spreadsheets for decades to track fuel use and maintenance on my cars. My 2016 MS90D was my first venture into the world of EV so I decided the analogous approach was to periodically record the values from the trips screen. When I'm largely driving locally, I'll capture the trip meter values, distance travel, kWh consumed on a weekly basis. When I've traveling, I'll capture it at each supercharging stop. Easiest way is I'll quickly snap a photo of the trips tab on the main screen, then when convenient, I add it to my spreadsheet log. The values are all linear, so even if I don't reset the trip counters, I can do simple deltas between various points in time to get interval averages.

In the first plot I posted, the open symbols are the individual interval values, so typically about every week or couple hundred miles. The solid line in that plot is the average use for those ranges, generally corresponding to when I decide to reset my Trip A.

For the second plot by quarter, I simply calculate deltas between the start of the quarters to get total distance traveled and kWh used to then calculate the average Wh/mile values for the period.

I do have my own logger program that I also run to pull data directly from my car, but the trip values or Wh/mi values are not broadcast. I can back calculate/infer them from the RM data broadcast, but the values in the plots which I've shown are pulled directly from screens in the car.

Yeah, I really am this big of a data nerd !!!
 
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If you car is sitting outside overnight, then you will see quite high Wh/mi numbers on the first drive of the day as energy is used to warm up the pack. You can reduce this by preheating the car, but that doesn't necessary reduce your total energy consumption, but makes your Wh/mi number look better as the trip display Wh/mi number only considers energy use while the car is driven, not parasitic energy consumption for such things as preconditioning. If you have the ability to charge at home, the most efficient way to preheat the battery is charging and timing your charing to end shortly before your scheduled departure.

For context, here's 5.5 years, 65k miles of real world data off of my MS90D. I think I'm base a little farther south than you, in south central Indiana, so not as cold on average but has winter trips through the NE included. While my lifetime average is right around 278 Wh/mi, you'll see some individual trip dots as high as 500 Wh/mi and other warm weather driving as low as the 240s. I don't tend to drive quite as fast as you, probably more like 73-75 on interstate, so that also influences some difference. You can clearly see the seasonal variation due to largely ambient temperature.

View attachment 732818

My car is garaged but I usually don’t use my heater much in the garage because it’s electric also. Will it help if I turn on cabin heat in the morning while car is still plugged in?
 

ATPMSD

Active Member
Mar 12, 2021
1,130
1,011
Atlanta, GA
My car is garaged but I usually don’t use my heater much in the garage because it’s electric also. Will it help if I turn on cabin heat in the morning while car is still plugged in?

Turning on cabin heat will not warm the battery. Look at scheduled departure / precondition (in the car, not on the app).
 
How come? I always turn my cabin heat on prior my drive. It will start to warm the cabin and eventually battery wil be heated as well. You can see the battery heating icon on the app coming on after a short while. In cold wheather battery charging does not heat your cabin and low power charging does not heat your car battery either. So as suggested, if you charge your car before you intend to leave/start to drive then there are options to choose your charging with battery precondition.
 
I have a 2018 model S 75d with 34k miles on it. I’ve been averaging mid to high 300 WH/MI and at times up to 420. Is this normal for a mix of city and highway driving? I’m driving somewhat aggressive and usually set cruise at 82. Ive also had a yellow triangle warning show a couple of times on the WH/MI gauge. Does anyone know what that warning means?
I have a 2017 S75D with around 30k miles on it. Current average is 384 WH/MI.

I'm not driving as fast as you, but the winter is killing my efficiency. On long road trips I've done in the summer (like 1,000 mi), my average would be 280 driving mostly around 70mph. In town in the summer it's 320.
 

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