Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Can Never Match Trip Planner Prediction

This site may earn commission on affiliate links.

mknox

Well-Known Member
Aug 7, 2012
10,104
1,901
Toronto, ON
I've mentioned this in passing in several threads, but for some reason, I can never seem to match the Trip Planner prediction in the Tesla Energy app. I am always below the grey prediction line, and usually by quite a bit.

Yesterday I had an approximately 25 mile trip to make after work and thought I'd try my best to meet or beat the prediction. It was over moderately hilly terrain (for Ontario), perfect weather in the 70s and I drove at or below the speed limit as gingerly as I could.

I unplugged from my charger at work at about 92% SOC and as you can see below, my trip (Since Last Charge) came in at 255 Wh/mi which I believe is better than Rated. But I'm still below the prediction line on the Energy Trip app! This is about as close as I've come to it, however.

What on earth do you have to do to meet Tesla's prediction?!?

IMG_0456.JPG
IMG_0455.JPG
 
strange.
and strange the the predicted like vs the green 'actual' line have such different undulations. my trip lines have looked much more similar for the most part
I would have probably ended at 85-6% or better with that trip.
maybe there is a googly error in Miles to Kilometer conversion there? probably not
 
The pavement may be rougher in Ontario than in California. fwiw, I don't have much of a problem meeting or beating the estimate in the Summer. Winter is another story, of course. I wonder if the algorithm has been overhauled for severe cold.

This route was on smooth fairly recent pavement, so that's not the issue here. But even if it was, how do I manage 255 Wh/mi but still come in under the prediction? That's what has me stumped. Sure, if I was coming in at 350 or 400 Wh/mi, I can see the prediction being off.

I received the firmware update with this feature in the cold of winter and I was WAY below the prediction then. I just chalked it up to the cold and figured it would get better in the spring/summer. It did get better, but still not close to the prediction.
 
You got behind in the first 2 miles, then kept up after that. Tesla sometimes doesn't get things like estimated speed or slope or pavement quite right which could contribute.
Otherwise I don't know how much Tesla takes into consideration p versus nonp or wheel size, or type of tire.
I doubt battery degradation would matter as the metering tries to take account of that... It seems to calculate power use mostly separate from battery state.
 
You got behind in the first 2 miles, then kept up after that. Tesla sometimes doesn't get things like estimated speed or slope or pavement quite right which could contribute.
Otherwise I don't know how much Tesla takes into consideration p versus nonp or wheel size, or type of tire.
I doubt battery degradation would matter as the metering tries to take account of that... It seems to calculate power use mostly separate from battery state.

P/ not P makes no difference. Tires will get you better Whr/km (or mi) but that is shown in the usage. and the low power used in the trip meter should have resulted in the green line very much above the grey line
If my S was behind in the first 2 miles like that and running at 255Whr/mi, I would not be behind, but well ahead very shortly after. The trip prediction is closer to ideal than rated from what I have seen.
 
Yeah good point. I wonder if the trip planner estimates capacity or assumes a like-new battery.

I actually wondered that myself. Despite every balancing and "range restoration" trick in the book, the best I currently get is 219 Rated at 90% and 242 Rated at 100%. I got 265 on the nose at 100% when the car was near new. On the other hand, as @cantdecide suggests, I would have thought the algorithm would take all this into account.
 
Why would p non P not make a difference? Doesn't that make a significant range difference in at least a new model S?
242 sounds low to me... I'm over 2 years and 38kmiles and still 259. Perhaps there is something with either your battery, battery measurement etc that is sub par.
Battery measurement is a difficult and complex science and sometimes the Tesla seems to get it wrong... And gradually correct later... Like the time I drove for 10 miles up hill and retained 100% the whole time.
 
It could be that the maps have inaccurate information about elevation changes in your area. Also, the trip planner is not based on rated range but rather speed limit on the roads your're on. So for example if you're on back roads then it would expect much better than 300w per mile.
 
Why would p non P not make a difference? Doesn't that make a significant range difference in at least a new model S?

Actually, no. The differences are between the D and the non-D cars. If you drive a P like a non-P you supposedly get the same efficiency.

242 sounds low to me... I'm over 2 years and 38kmiles and still 259. Perhaps there is something with either your battery, battery measurement etc that is sub par.

I have brought it to the attention of my Service Center and they say the battery is operating normally and as designed.
 
I sometimes beat it, not always. I always beat it when I try though.

Define try?

If I have range mode on, and do less than or equal to 70mph on a 100+ mile trip, I ALWAYS beat it. If I do 75mph, I SOMETIMES beat it under the same conditions. If I do 80mph, I never beat it.

[last 3 months of driving. I guess winter may be different, but you've had your car about the same time as me]
 
Define try?

If I have range mode on, and do less than or equal to 70mph on a 100+ mile trip, I ALWAYS beat it. If I do 75mph, I SOMETIMES beat it under the same conditions. If I do 80mph, I never beat it.

[last 3 months of driving. I guess winter may be different, but you've had your car about the same time as me]

I always have range mode off. Try would mean I drive 55 or below with few stop-and-go accelerations vs. 65-70. City driving absolutely won't beat it with all the stop-and-go and hills around me. But even from city to city, if I go the speed limit, I won't beat the prediction.
 
It could be that the maps have inaccurate information about elevation changes in your area. Also, the trip planner is not based on rated range but rather speed limit on the roads your're on. So for example if you're on back roads then it would expect much better than 300w per mile.

actually is based on speeds people drive on the road, not the speed limits from what I was told by someone at Fremont - which matches up with what I have seen driving between Humboldt and SF area.

From my home to the Petaluma SC is 232 miles and I have a 106% trip based on the trip prediction but can just make it while driving the speed limit + 5-7mph