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Loss in efficiency with 2019.32.12.2

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
After the latest update the wh/mi on my normal commute has increased from 223 wh/mi to ~280wh/mi.

My range estimate has not changed as I'm still seeing 254 miles at 80% which is consistent over the time I've had the car. This is a LR RWD with 7500 miles on it.

Has anyone else seen this behavior? I'm considering calling the service center to see if the can remotely diagnose but wanted to check on the forum first. I drive pretty conservatively in terms of energy consumption and have been consistently at about 223 wh/mi on this certain drive. I tried no autopilot and even chill mode but it didn't help. Temperature has dropped about 15F outside here in the PNW but I had the car last March in the same temperatures without this drastic loss in efficiency.

I'm wondering if something in the latest release is using up more energy while driving or if it is isolated to my vehicle. I have hard reset and nothing changed. Any input is appreciated.
 

Zirak

Member
May 3, 2018
325
170
Canada
I clocked about 204.387 wh/mile (127 wh/km) the other day on my LR RWD in Canada with only seat heaters and no cabin heat, with 15C temp. I guess the difference is due to the temperature. Even if you don't use the cabin heater, the battery will still use its own energy to heat itself up. Is this your first fall/winter for your M3? If so... this is normal, and welcome to the EV world of driving in the winter :)
 

ecarfan

Well-Known Member
Sep 21, 2013
19,395
14,407
West Vancouver, British Columbia
I'm wondering if something in the latest release is using up more energy while driving or if it is isolated to my vehicle. I have hard reset and nothing changed. Any input is appreciated.
Colder weather uses more energy. Not sure what the temperatures have been lately in “rat hole, usa”, but that might have something to do with hit.
 

Zirak

Member
May 3, 2018
325
170
Canada
Colder weather uses more energy. Not sure what the temperatures have been lately in “rat hole, usa”, but that might have something to do with hit.
I believe he mentioned 15F in his original post, which is pretty cold for a California built Tesla ;)
 

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
I believe he mentioned 15F in his original post, which is pretty cold for a California built Tesla ;)


I'm in the Pacific NW. Temperature has dropped 15F to about 50F. So most likely it is not only temperature related. Also as I mentioned I had the car in March 2019 at the same temperatures and didn't see this effect. Has anyone else seen a decrease in efficiency? This is nearly a 30% decrease in efficiency with a modest temperature decrease. I'm not running heaters and yes battery needs to be warmed but this didn't happen last spring.
 

RyanT

Member
Sep 9, 2014
388
161
Portland
I'm in the Pacific NW. Temperature has dropped 15F to about 50F. So most likely it is not only temperature related. Also as I mentioned I had the car in March 2019 at the same temperatures and didn't see this effect. Has anyone else seen a decrease in efficiency? This is nearly a 30% decrease in efficiency with a modest temperature decrease. I'm not running heaters and yes battery needs to be warmed but this didn't happen last spring.

I'm in the PNW too. If the roads are wet the efficiency goes down. Anytime you're kicking up water from your tires it takes energy. Things don't move on their own. If it's a heavy rain it's very noticeable.
 

Funkmobile

Member
Apr 5, 2018
667
657
Vancouver
If you live in the Pacific North West, then weather is a definite contributing factor in your loss of efficiency. The updates just so happens to coincide with the recent change in weather.
 

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
I'm in the PNW too. If the roads are wet the efficiency goes down. Anytime you're kicking up water from your tires it takes energy. Things don't move on their own. If it's a heavy rain it's very noticeable.

I realize rolling resistance and drag increase in the rain. The efficiency decrease happens in perfectly dry weather too like yesterday. So nope that wasn't it.
 

Kappelan

Member
Jul 23, 2019
281
141
Greater Toronto Area
Looks like I've lost about 5 km. Before the update it was showing 345 km at 90%, now I am getting 241-240 km. But I can blame it on the weather as well. It is getting colder here.
 
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Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
Looks like I've lost about 5 km. Before the update it was showing 345 km at 90%, now I am getting 241-240 km. But I can blame it to the weather as well. It is getting colder here.

My range estimate has NOT changed. I pay close attention to my wh/mi used and immediately after the last update 2019.32.12.2 my efficiency decreased by 25% and I started using 280wh/mi. Before the update I was getting around 223 wh/mi.
 
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Reactions: Kappelan

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
Another thought: I have FSD package with HW2.5. I'm wondering if the latest update is making greater use of the processing capabilities of HW2.5 and we are starting to see the effects on energy efficiency. Anyone else with FSD on HW2.5 seeing an efficiency decrease with the latest update?
 

woodisgood

Slightly faster than 5mph
Jul 26, 2018
2,610
14,106
San Francisco
No use dwelling on what's going on in 32.12.2...another update coming very shortly that will add efficiency improvements and stronger regen.
 

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
No use dwelling on what's going on in 32.12.2...another update coming very shortly that will add efficiency improvements and stronger regen.

That is a good point.... However, I'm trying to determine if I have an issue with my vehicle that requires service. If something is drawing extra power when it shouldn't be that could be a sign of an issue that I would like to address before any potential damage occurs. If it is normal and other owners have experienced the same thing with the latest update then I would feel relieved. I'll wait a bit longer to see if anyone else has the experience before contacting Tesla. Thanks for your input.
 

5_+JqckQttqck

Active Member
Apr 27, 2018
1,851
1,404
Toronto
Another thought: I have FSD package with HW2.5. I'm wondering if the latest update is making greater use of the processing capabilities of HW2.5 and we are starting to see the effects on energy efficiency. Anyone else with FSD on HW2.5 seeing an efficiency decrease with the latest update?

Lets get the variables.

Model / Setup?
Same normal commuting routes?
Tire changed to winters?
Cabin temperature settings?

Personally I've noticed the average Wh/km is inching up (excuse the pun) from the rated to about +10 to 20% more energy needed.

During the summer; to drive 50kms, I used 48 to 51km of "rated" battery power to achieve ~100% efficiency.
Now that the mercury has been dropping. It can fluctuate anywhere from 50% to 80% efficiency depending on the trip length and how fast I like to drive; numbers match up to yours.

130Wh/km*1.61 = 209Wh/mi
150*1.61 = 241.5
170*1.61 = 273.7 (~10C @ 80ish% efficiency) - closes to your numbers.
180*1.61 = 289.8
190*1.61 = 305.9


upload_2019-10-24_12-40-38.png



Do you have a chart with data from a 3rd party data collector to show this change in efficiency?
 

woodisgood

Slightly faster than 5mph
Jul 26, 2018
2,610
14,106
San Francisco
That is a good point.... However, I'm trying to determine if I have an issue with my vehicle that requires service. If something is drawing extra power when it shouldn't be that could be a sign of an issue that I would like to address before any potential damage occurs. If it is normal and other owners have experienced the same thing with the latest update then I would feel relieved. I'll wait a bit longer to see if anyone else has the experience before contacting Tesla. Thanks for your input.

Sorry, I didn't mean to be dismissive of the possibility that there may be an issue with your car. My point was just that IF something changed due to the latest software, it will probably change again with the next one.

Assuming you haven't changed tires or anything?

As others have mentioned, the colder temperatures, wetness, etc. can all make a difference. Another factor that is often not noticeable but causes significant variation in efficiency is wind, i.e. it won't be any windier outside but you were getting a dead-on headwind for the bulk of your drive. My current highway efficiency tends to be between 200-210 wh/mi in 70 degree Bay Area. Drop the temps into the 50s, add a bit of headwind or drizzle and it can be up in the 240-250 range.
 

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
Thanks, woodisgood. I haven't changed tires and the temps are in the 50s here now. I appreciate the feedback. A portion of my efficiency loss is definitely due to the temperature. I guess I'll have to wait for warmer weather to know for sure.
 

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
Lets get the variables.

Model / Setup?
Same normal commuting routes?
Tire changed to winters?
Cabin temperature settings?

Personally I've noticed the average Wh/km is inching up (excuse the pun) from the rated to about +10 to 20% more energy needed.

During the summer; to drive 50kms, I used 48 to 51km of "rated" battery power to achieve ~100% efficiency.
Now that the mercury has been dropping. It can fluctuate anywhere from 50% to 80% efficiency depending on the trip length and how fast I like to drive; numbers match up to yours.

130Wh/km*1.61 = 209Wh/mi
150*1.61 = 241.5
170*1.61 = 273.7 (~10C @ 80ish% efficiency) - closes to your numbers.
180*1.61 = 289.8
190*1.61 = 305.9


View attachment 469557


Do you have a chart with data from a 3rd party data collector to show this change in efficiency?

This is good info. Much appreciated.

LR RWD with FSD 7500 miles stock tires.
Same route
Cabin temperature OFF
Temperatures in the mid low to mid 50Fs (~12C)

I'm not using any third party data collector. I note the efficiency after each drive and strive to keep it low. According to your chart I'm not far off what would be expected. Where did you get that chart from? Is that from your own vehicle's data? Very helpful. Thank you.
 

Burrito

Member
Apr 29, 2019
581
424
New jersey
theres a facebook thread regarding this topic as well.

put me in the camp that v10 messed up efficiency. temp in NJ has been pretty high for this time of year, and during some 65-70degree driving my efficiency took a 20-30wh/mi hit as well. my normal commute i do every day is all worse than before v10, i thought it was lowering my car at the same time as v10 but i should be getting better not worse from lowering
 

Don_Joe

Member
Jun 26, 2019
20
11
rat hole, usa
theres a facebook thread regarding this topic as well.

put me in the camp that v10 messed up efficiency. temp in NJ has been pretty high for this time of year, and during some 65-70degree driving my efficiency took a 20-30wh/mi hit as well. my normal commute i do every day is all worse than before v10, i thought it was lowering my car at the same time as v10 but i should be getting better not worse from lowering

Interesting, burrito. Can you point me to the facebook thread? your experience sounds similar to mine. Agreed that you lowering your car *shouldn't effect the wh/mi negatively unless somehow the airflow got worse and caused more turbulence than before lowering. Not likely though imo. I did not modify my car whatsoever and seeing similar to what you are seeing after the update. Thanks for the data point.
 

KenC

Active Member
Sep 4, 2018
3,752
3,486
Maine
After the latest update the wh/mi on my normal commute has increased from 223 wh/mi to ~280wh/mi.

My range estimate has not changed as I'm still seeing 254 miles at 80% which is consistent over the time I've had the car. This is a LR RWD with 7500 miles on it.

Has anyone else seen this behavior? I'm considering calling the service center to see if the can remotely diagnose but wanted to check on the forum first. I drive pretty conservatively in terms of energy consumption and have been consistently at about 223 wh/mi on this certain drive. I tried no autopilot and even chill mode but it didn't help. Temperature has dropped about 15F outside here in the PNW but I had the car last March in the same temperatures without this drastic loss in efficiency.

I'm wondering if something in the latest release is using up more energy while driving or if it is isolated to my vehicle. I have hard reset and nothing changed. Any input is appreciated.
As mentioned in other similar threads, a 15deg drop in temp can easily mean a 10% increase in energy use. You're showing a 20% increase. Has it been raining? Because that can also increase energy use by 5 to 10%.

Since the temps dropped, have you compensated by adding any air to your tires?
 
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