Winter Tire Efficiency

[jc22zhao]

Hey Everyone, I just have a quick question regarding efficiency with winter tires/winter driving in general in a model 3.

Post is kinda long so here's the TL;DR
Summer consumption = 130Wh/km
Consumption prior to winter tire switch and update to 2019.36.1 = 170Wh/km
After tire switch and update = 190-200Wh/km
Is this normal?


Full Post:
I have a Model 3 SR+ with 18" wheels (w/ FSD).

I recently installed the factory winter tire package with 18" Aero rims (without cap) and Pirelli Sottozero 2 (Tesla spec) tires.

I noticed my daily commute average consumption just prior to switching to winter tires was roughly 170Wh/km (down from the 130Wh/km in summer).

I switched tires on the same day as getting the 2019.36.1 update which was "supposed to improve efficiency and power in model 3s by up to 5%".

Immediately after the switch, I noticed my consumption has increased to about 190Wh/km and with the recent cold spell in the GTA area over the last couple days, it's hitting nearly 200Wh/km (this is averaged out between morning and evening commute since my morning commute is always more efficienty from driving downhill).

Now, I realize the temperatures have also dropped by a few degrees over the last few days, but it shouldn't explain the sudden 12% increase in consumption, especially since the software update was supposed to increase fuel efficiency.

I plan on getting a car wash this weekend then installing the Aero caps in hopes of lowering the consumption, even if only by a few %.

Just wondering what others on this forum has been getting in terms of consumption after switch over to winter tires, and driving in cold weather in general. Is my consumption increase in the normal range? Or should I be concerned?

Just as a side note: driving back from downtown to richmond hill yesterday yielded an average trip consumption of 230Wh/km. I was hoping even in worst case scenario in winter, I'd get half my range, but at this rate, it seems I'd have even less than half during a bad winter storm.

 

[5_+JqckQttqck]

Hey Everyone, I just have a quick question regarding efficiency with winter tires/winter driving in general in a model 3.

Post is kinda long so here's the TL;DR
Summer consumption = 130Wh/km
Consumption prior to winter tire switch and update to 2019.36.1 = 170Wh/km
After tire switch and update = 190-200Wh/km
Is this normal?


Full Post:
I have a Model 3 SR+ with 18" wheels (w/ FSD).

I recently installed the factory winter tire package with 18" Aero rims (without cap) and Pirelli Sottozero 2 (Tesla spec) tires.

I noticed my daily commute average consumption just prior to switching to winter tires was roughly 170Wh/km (down from the 130Wh/km in summer).

I switched tires on the same day as getting the 2019.36.1 update which was "supposed to improve efficiency and power in model 3s by up to 5%".

Immediately after the switch, I noticed my consumption has increased to about 190Wh/km and with the recent cold spell in the GTA area over the last couple days, it's hitting nearly 200Wh/km (this is averaged out between morning and evening commute since my morning commute is always more efficienty from driving downhill).

Now, I realize the temperatures have also dropped by a few degrees over the last few days, but it shouldn't explain the sudden 12% increase in consumption, especially since the software update was supposed to increase fuel efficiency.

I plan on getting a car wash this weekend then installing the Aero caps in hopes of lowering the consumption, even if only by a few %.

Just wondering what others on this forum has been getting in terms of consumption after switch over to winter tires, and driving in cold weather in general. Is my consumption increase in the normal range? Or should I be concerned?

Just as a side note: driving back from downtown to richmond hill yesterday yielded an average trip consumption of 230Wh/km. I was hoping even in worst case scenario in winter, I'd get half my range, but at this rate, it seems I'd have even less than half during a bad winter storm.

The short answer is the energy to warm up the cabin to a comfortable level. Unlike ICEV (uses heat from combustion), EVs use energy intensive resistive heating elements to heat the cabin.

Short trips (Go to work, drive to coffee during break, drive to lunch, drive to market after work, drive to X activity, drive to get kids etc.) expect to losses close to 50% due to heat/car warm up.

Long road trip (one shot from SC to SC), expect losses about 20 to 30% depending on your cabin heat settings.

Solution is to use the heated seats and a blanket for your legs to keep the cooler air off (most of us drive solo to work). I had cabin temperature set to 15.5°C this morning at my consumption was about 160Wh/km with 1bar of "hot butt".

 

[martind3]

I'm in Ottawa, but with the drop in temperatures the last few days, I'm averaging 206Wh/km. This is with 2019.32.12.2 and the stock tires. I don't switch over to winter tires until this weekend. Most of the fall I was averaging about 160-165Wh/km.

I don't think Toronto has been as cold as Ottawa so may not be a good comparison.

 

[jc22zhao]

The short answer is the energy to warm up the cabin to a comfortable level. Unlike ICEV (uses heat from combustion), EVs use energy intensive resistive heating elements to heat the cabin.

Short trips (Go to work, drive to coffee during break, drive to lunch, drive to market after work, drive to X activity, drive to get kids etc.) expect to losses close to 50% due to heat/car warm up.

Long road trip (one shot from SC to SC), expect losses about 20 to 30% depending on your cabin heat settings.

Solution is to use the heated seats and a blanket for your legs to keep the cooler air off (most of us drive solo to work). I had cabin temperature set to 15.5°C this morning at my consumption was about 160Wh/km with 1bar of "hot butt".

Hey thanks for the response. Just to add some more context, my commute to work is around 37km one way. About 25km of that is spent on the highway (half the time is stop and go, the other half is cruising at 115-120km/h). So it's sort of long-ish (45m in the morning, 1h 15m in the evening).

I understand significant energy could be used for warming of cabin, up to 7kW for the air heaters, however, since the latest update, I've been using the scheduled departure feature to warm up the car before unplugging. I also have a charger at work and I usually preheat the car about 5 mins before I set off. I've also played around with turning on recirc, while the car is already driving to reuse some of the already heated air instead of always pulling in cold outside air.

I usually preheat the car prior to driving (around 5mins) as I usually have it plugged in. But since my heating habits have been consistent before and after the tire change, I don't think it should increase it that much, especially not the extra 12% jump after changing to winter tires.

The tech at the tesla service center said I should not experience a significant range drop between all season vs winter tires. But according to my projections, I should be at around 175-185Wh/km (since I was averaging 170Wh/km) just 1 week ago, but not the 190-200Wh/km that I am actually seeing.

I guess what I really want to find out from other members of the forum is whether most people experience a somewhat significant consumption increase after switching to winter tires (10-15%) or is it just me? And if it's just me, then I would need to dig deeper as to what is causing this increase.

 

[thesteve]

I think it’s not just about heating the cabin, the battery is like us, prefers a certain range of temperature. Some energy is spent keeping the battery at optimal temperature.

 

[jc22zhao]

I think it’s not just about heating the cabin, the battery is like us, prefers a certain range of temperature. Some energy is spent keeping the battery at optimal temperature.

I was also thinking that but here's some things to consider.
- If there is some passive battery conditioning, i should experience a higher than normal phantom drain when parked, since that is when the battery is the coldest. That is not the case, my idle losses are around the same as before.
- I "almost-always" charge the battery prior to my commute (240V UMC at home before the morning commute, and 208V J1772 at work before my evening commute), this should heat up the battery by some amount prior to departure
- I believe dedicated battery heating only occurs when the car is pre-conditioning prior to supercharging, when you navigate to a supercharger with a cool battery
- Model 3 does not come with a dedicated battery heater, and instead relies on heating up the motor stators, then using the cooling loop to pump the heat into the batteries. And that heat is usually from regular driving loads, except when in the pre-conditioning situation i described above (please correct me if this is wrong)

I'm tempted to get the ODBII adapter and get some real time monitoring on the battery drain to figure this out.

 

[PJFW8]

The short answer is the energy to warm up the cabin to a comfortable level. Unlike ICEV (uses heat from combustion), EVs use energy intensive resistive heating elements to heat the cabin.

Short trips (Go to work, drive to coffee during break, drive to lunch, drive to market after work, drive to X activity, drive to get kids etc.) expect to losses close to 50% due to heat/car warm up.

Long road trip (one shot from SC to SC), expect losses about 20 to 30% depending on your cabin heat settings.

Solution is to use the heated seats and a blanket for your legs to keep the cooler air off (most of us drive solo to work). I had cabin temperature set to 15.5°C this morning at my consumption was about 160Wh/km with 1bar of "hot butt".

And precondition while plugged in if possible.

 

[bijan]

Just as a side note: driving back from downtown to richmond hill yesterday yielded an average trip consumption of 230Wh/km. I was hoping even in worst case scenario in winter, I'd get half my range, but at this rate, it seems I'd have even less than half during a bad winter storm.

Here's my consumption data from teslafi on an LR AWD for all my trips from October 2018 until now, climate on auto 20C in the cold, almost never preheating:
(You can ignore the top and bottom temperatures, since there are so few km).

 

[5_+JqckQttqck]

Winter tires are softer and stickier on dry roads. Winter air resistance is higher due to more molecules per square inch in colder temps. All variables to make life with EV more interesting in the winter here

 

[jerry33]

New tires have more rolling resistance at first and continue to reduce rolling resistance as they break in and wear down (applies to both winter and summer tires). Winter tires have deeper tread than summer tires, so there is more squirming of the tread compound when new. This is in addition to the usual winter issues of dense cold air, wet or snowy pavement, heater running, etc. I'd wait a 2-3,000 km and see if they don't get better.

 

[bwalter]

As others have said, winter tires will cause some range loss due to increase rolling resistance due to the fact that they are softer. Are your tire pressures the same? Lower temperatures will cause lower tire pressure and lower tire pressure will also increase rolling resistance.

Granted, tires are just one factor. The temperature is probably another, as even with preconditioning it will take more energy to maintain the cabin temperature for the duration of your commute. As for the update, I wouldn't expect any real efficiency improvement, it's just they are comfortable with tweaking the constant they use for their calculations to show a bit more range.

 

[sheamurai]

From what I've read, the tweak in range isn't better "fuel efficiency". I believe the only improvement was in the regen capabilities, so now you can regen all the way to a full stop - this accounts, I believe, for the extra energy they are using to increase their range projection. So, when it's cold out, your regen is reduced anyway, so you won't actually see the full benefit of the increase until the warmer months. My interpretation so far anway, tho I may have missed an article out there.

 

[mahagala]

Hey Everyone, I just have a quick question regarding efficiency with winter tires/winter driving in general in a model 3.

Post is kinda long so here's the TL;DR
Summer consumption = 130Wh/km
Consumption prior to winter tire switch and update to 2019.36.1 = 170Wh/km
After tire switch and update = 190-200Wh/km
Is this normal?


Full Post:
I have a Model 3 SR+ with 18" wheels (w/ FSD).

I recently installed the factory winter tire package with 18" Aero rims (without cap) and Pirelli Sottozero 2 (Tesla spec) tires.

I noticed my daily commute average consumption just prior to switching to winter tires was roughly 170Wh/km (down from the 130Wh/km in summer).

I switched tires on the same day as getting the 2019.36.1 update which was "supposed to improve efficiency and power in model 3s by up to 5%".

Immediately after the switch, I noticed my consumption has increased to about 190Wh/km and with the recent cold spell in the GTA area over the last couple days, it's hitting nearly 200Wh/km (this is averaged out between morning and evening commute since my morning commute is always more efficienty from driving downhill).

Now, I realize the temperatures have also dropped by a few degrees over the last few days, but it shouldn't explain the sudden 12% increase in consumption, especially since the software update was supposed to increase fuel efficiency.

I plan on getting a car wash this weekend then installing the Aero caps in hopes of lowering the consumption, even if only by a few %.

Just wondering what others on this forum has been getting in terms of consumption after switch over to winter tires, and driving in cold weather in general. Is my consumption increase in the normal range? Or should I be concerned?

Just as a side note: driving back from downtown to richmond hill yesterday yielded an average trip consumption of 230Wh/km. I was hoping even in worst case scenario in winter, I'd get half my range, but at this rate, it seems I'd have even less than half during a bad winter storm.

One thing you can try is turn off heater while commute. Make sure you wear enough to keep you warm.

 

[Casmium]

Do you park inside or outside, just from parking in my garage the car is warmer and takes less energy to heat up so I end up with a lower wh/km compared to when I park outside

 

[jc22zhao]

Hey, so some updates and to address some comments:
1. Tire pressure is roughly equivalent to my all season set, i check my tire pressures on each drive (sometimes multiple times) and i make sure they are always above 40psi and less than 50psi and any point of my drive, i've had to add air to my all seasons prior to switching to winter tires, due to the colder temperature reducing tire pressure to below 40psi.
2. I park indoors overnight (garage is ~10C) and preheat for 5 mins in the morning. I park in an outdoor multilevel parking during the day, and for the most part, I plug in about 2-3hrs prior to leaving, and I preheat for about 5-10 mins before leaving.
3. I installed aero caps back on over the weekend and noticed some amount of improvment. On my morning commute today, i achieved a 160Wh/km commute downtown, but since my morning commute is always more efficient than evening commute (mostly downhills) i was gonna wait till I get back home to average out the numbers. But seeing as it is a complete whiteout in Toronto today, my evening commute numbers will most likely be adversely affected.

 

[Darthbenji]

My drive today was horrible for efficiency. Left with 333kms and got home with 17. I drove 152 kms. It was a mix of highway and city. 3 trips total. The first when leaving home was preheated and charged up right before leaving. Never saw below 204 wh/km

 

[PJFW8]

My drive today was horrible for efficiency. Left with 333kms and got home with 17. I drove 152 kms. It was a mix of highway and city. 3 trips total. The first when leaving home was preheated and charged up right before leaving. Never saw below 204 wh/km

Why charge only to 333kms?

 

[Darthbenji]

Why charge only to 333kms?

90% on a Sr+

 

[PJFW8]

90% on a Sr+

Got it

 

[xG35]

It is primarily because of heating cabinet.

The effect is less if you are going on a roadtrip, but city driving will yield results discussed above. After driving the S for 4 years, while preheating will help at home on your initial trip.