Winter - excessive battery range reduction...

[claud_face]

I am in Chicago. Got a 100d. Heading up to Wisconsin. Exact destination is 202 miles away. I will fully charge as well as preheat and give you some results. Didn't really think much about range originally when buying the 100d. Decided on it because of the inventory discount. Glad I did as 259 miles on the 75D in this weather seems like it would not last. Temp will be roughly 15F on Thursday night. I will be leaving Wisconsin on Sat night/ Sunday morning with temp between 0-8F.

Will be interesting... Stay posted.

 

[thefortunes]

I am in Chicago. Got a 100d. Heading up to Wisconsin. Exact destination is 202 miles away. I will fully charge as well as preheat and give you some results. Didn't really think much about range originally when buying the 100d. Decided on it because of the inventory discount. Glad I did as 259 miles on the 75D in this weather seems like it would not last. Temp will be roughly 15F on Thursday night. I will be leaving Wisconsin on Sat night/ Sunday morning with temp between 0-8F.

Will be interesting... Stay posted.

You should be able to make it (subject to wind/snow of course).

Depending on where you are heading Tesla just opened new SuC in Madison (about 2 miles west of the set at East Towne) and Oshkosh in addition to the ones you may know about in Pleasant Prairie, Sheboygan, Green Bay, LaCrosse and WI Dells. (Note: I only listed those within 200 miles of Chicago).

 

[Brian-MS90D]

Potentially one big variable in @Navsarin 's scenario is your preheating practice. Specifically, did you actually preheat the battery or merely the cabin? You stated:
"Preheated the cabin (and presumably the battery) for 30 min while plugged in.."

What was your state of charge when you began preheating? Were you actually charging (and therefore heating the battery)? If you were already at 100% SOC when you started "preheating," then you were not preheating. The cabin and battery heater do not heat the battery that much. Also, the cabin heater can consume ~ 80% of the electric wall supply leaving only 20% going to charge the battery (and therefore heat the battery very little). Charging is the best way to preheat the battery.

Another way to ask my question here is what was your regen ability when you started? If you didn't have regen for a good portion then that is one possible explanation for decreased range than normal (depending on how flat your drive was).

Did you preheat the cabin before your return drive? Heating the cabin from the battery pack - especially preheating - will really cut your range (i.e, consume a lot of battery power). I assume your regen was limited on the return?

-18c is fairly cold and if you use the cabin heater at the beginning of a trip when the motors are cold then you'll consume a lot of electricity heating your cabin's air.

 

[Richgoogol]

I too was on my way back from a family trip yesterday. And I too noticed a huge reduction in useable mileage. Although I was a bit more conservative than you since I drive a 75D and only planned 15%~20% reserve from Supercharger to Supercharger. It was my wife and I with skis and luggage, I was driving about 95-105km/hour depending on the battery prediction and on several occasions we had to turn off cabin heating, also tail gating a truck in order to make it to the Supercharger. Based on my calculation, we still had a reduction of 25~30% reduction in range even after doing that. So not sure if wife wants to do a trip in the Tesla again.

 

[claud_face]

thefortunes.

Yes, I should be fine. And even with a 75D I could easily stop by a supercharger. However, I travel this route often and at about 3 hours when continuously driving it is nice not to have to stop for a charge.

Either way I'll chime in after the weekend.

 

[clostridium]

I've had a pretty similar experience at colder temps to the TeslaFi numbers posted below. As others have noted if you can have the car plugged in to offset the energy cost of preheating the battery and the cabin it makes a pretty big difference. Once all that is heated up the efficiency isn't too bad on clear roadways even in sub freezing temps. I probably average 330-340 when it's in the 20's even on snow tires and including some trips where preheating didn't occur.

I know this doesn't directly answer your question but I switched to the battery percentage display early on and found it more useful and less distracting. I have a 75D so each 1% is 750 Wh and I know that in normal weather (i.e. > 40 F) I can comfortably bank on 2.5 miles/percent (~300 Wh/mi) unless it's a massive downpour or bad headwinds. In cold weather around freezing I budget 2 miles/percent (~375 Wh/mi) and at weather colder than freezing especially short trips I conservatively do 1.5 miles/percent (~500 Wh/mi).

The good news is that on longer trips (when you'd generally be worried about range) things even out more. It's the shorter trips where the heating part of the energy consumption becomes a much bigger factor. The rated range just got on my nerves and really wasn't useful.

Question for the more knowledgeable people out there - is there any benefit to plugging in to 110 V/15 A circuit? Does the battery heater have a minimum amount of power it needs or does it just heat slower when working with less power? I know that the battery heater + cabin heater could likely draw 12 kW together but wasn't sure if there's still benefit at lower power delivery levels. It seems like this should still help but wanted to verify. Only 110 V available at work.

Craig

Our data from TeslaFi:
View attachment 269052
View attachment 269053

 

[thefortunes]

I've had a pretty similar experience at colder temps to the TeslaFi numbers posted below. As others have noted if you can have the car plugged in to offset the energy cost of preheating the battery and the cabin it makes a pretty big difference. Once all that is heated up the efficiency isn't too bad on clear roadways even in sub freezing temps. I probably average 330-340 when it's in the 20's even on snow tires and including some trips where preheating didn't occur.

I know this doesn't directly answer your question but I switched to the battery percentage display early on and found it more useful and less distracting. I have a 75D so each 1% is 750 Wh and I know that in normal weather (i.e. > 40 F) I can comfortably bank on 2.5 miles/percent (~300 Wh/mi) unless it's a massive downpour or bad headwinds. In cold weather around freezing I budget 2 miles/percent (~375 Wh/mi) and at weather colder than freezing especially short trips I conservatively do 1.5 miles/percent (~500 Wh/mi).

The good news is that on longer trips (when you'd generally be worried about range) things even out more. It's the shorter trips where the heating part of the energy consumption becomes a much bigger factor. The rated range just got on my nerves and really wasn't useful.

Question for the more knowledgeable people out there - is there any benefit to plugging in to 110 V/15 A circuit? Does the battery heater have a minimum amount of power it needs or does it just heat slower when working with less power? I know that the battery heater + cabin heater could likely draw 12 kW together but wasn't sure if there's still benefit at lower power delivery levels. It seems like this should still help but wanted to verify. Only 110 V available at work.

Craig

It certainly will help to "charge" at work on 120v/15a. When I have done this with the S, depending on the ambient temp, the regen is still limited (so the battery is not totally warm) but it is definitely better than a full cold soak.

In addition, preheating will draw from the pack since it uses 6kW which is significantly above the 1.8kW supplied from the wall.

Note that I have not done this since the new firmware which also allows battery preconditioning.

 

[Destiny1701]

Potentially one big variable in @Navsarin 's scenario is your preheating practice. Specifically, did you actually preheat the battery or merely the cabin? You stated:
"Preheated the cabin (and presumably the battery) for 30 min while plugged in.."


Well given I’m on .50, I assumed battery heating was included now with cabin pre-heat as stated. Is there a way to separately pre-heat the battery??

What was your state of charge when you began preheating? Were you actually charging (and therefore heating the battery)? If you were already at 100% SOC when you started "preheating," then you were not preheating. The cabin and battery heater do not heat the battery that much. Also, the cabin heater can consume ~ 80% of the electric wall supply leaving only 20% going to charge the battery (and therefore heat the battery very little). Charging is the best way to preheat the battery.

Charge was at 430km and I increased it to 100% charge which is 510km given the cold (first time ever going above 90%). By the time the battery was at 485k however. we had to unplug and go. I turned pre-heat on immediately after plugging in.

Another way to ask my question here is what was your regen ability when you started? If you didn't have regen for a good portion then that is one possible explanation for decreased range than normal (depending on how flat your drive was).

Regent was quite low as the car was at -18c. With brakes cold, one won’t get any regen if any until they warm up. The drive was relatively flat on the highway the entire trip.

Did you preheat the cabin before your return drive? Heating the cabin from the battery pack - especially preheating - will really cut your range (i.e, consume a lot of battery power). I assume your regen was limited on the return?

Only pre-heated the cabin for 3 minutes before we left to get the temp at least to -5 from -19c. Regen also limited as the car was super cold.

-18c is fairly cold and if you use the cabin heater at the beginning of a trip when the motors are cold then you'll consume a lot of electricity heating your cabin's air.

When we left the home, the cabin was already at 20c due to pre heat so I can’t imagine it worked hard to get us to 22c while we were on our way.
Case in point, the cold footwells were not a problem on the way out even at 5 fan setting.

 

[S100D]

Potentially one big variable in @Navsarin 's scenario is your preheating practice. Specifically, did you actually preheat the battery or merely the cabin? You stated:
"Preheated the cabin (and presumably the battery) for 30 min while plugged in.."

Turn Range Mode off when you are charging/preheating the battery. If you leave Range Mode on, only 1/2 the amperage is sent to the battery heaters. Tesla should automatically turn Range Mode off and then back on after charging but unfortunately they don't.

 

[Destiny1701]

Turn Range Mode off when you are charging/preheating the battery. If you leave Range Mode on, only 1/2 the amperage is sent to the battery heaters. Tesla should automatically turn Range Mode off and then back on after charging but unfortunately they don't.

Thanks range mode is now off. Didn’t know that . Today drove 20km and range dropped 45km. No ore heat however and weather -11c. I wonder if there is an issue with my battery heating.

 

[Big Earl]

Turn Range Mode off when you are charging/preheating the battery. If you leave Range Mode on, only 1/2 the amperage is sent to the battery heaters. Tesla should automatically turn Range Mode off and then back on after charging but unfortunately they don't.

Correction. The battery heater will only heat it up to 8C when range mode is off. With range mode is on, it lowers that setpoint significantly (I forget, but it's something below -10C). It essentially turns off the battery heater entirely until the battery temperature drops to its extreme lower limit.

 

[jdw]

The ideal way to use range mode in the OP's situation (preheat-long drive-park in the cold-drive home), would be to charge and preheat shortly before leaving home with range mode off. Once driving in a warm car, range mode on or off makes a small difference - in general, turn it on if you are warm enough. When you get to your destination and park, make sure range mode is on if you can't plug in. Range mode will stop or slow the battery heater draw on the frozen battery which will make a big difference in consumption on the way home. The motor and inverter will warm the battery naturally (and more slowly) as you drive.

When the battery is frozen, don't preheat, just turn on range mode and drive. Upside, is you'll save a lot of energy, downside is regen will be limited and cabin heater will be slightly reduced in output.

 

[Gen3]

Thanks range mode is now off. Didn’t know that . Today drove 20km and range dropped 45km. No ore heat however and weather -11c. I wonder if there is an issue with my battery heating.

is your car outside, garage, or heated garage? cold soaked car would explain excessive battery use on short trips. i drove through algonquuin last week at 95km/hr,-15C, and used 330km rated range for 235km drive.

 

[PaulC]

I'm near Toronto so I've been dealing with the same cold weather this week. I'm averaging about 260-270wh/km, around 300km total range (P90D, 410km rated). Never using range mode. Reasonable amount of preheating before leaving home. I keep the cabin set to 19C which is quite comfortable with the seat and steering wheel heaters.

The main thing you're running into is that when you start driving in very cold weather, the energy consumption has a huge bump and then levels out at a "normal" level (about 25% range loss, in my case). If you don't preheat at all and the overnight temp is -20C, the bump will be enormous. As you preheat longer, it shrinks. Extrapolating from the first 20km is just going to stress you out - I keep the dash display on % instead of range so I'm not sucked in to counting kilometers.

 

[PhaseWhite]

@Navsarin I'm afraid 30 minutes is not enough time to preheat when your battery is cold soaked. For best results, Id say you need at-least an hour and as others have mentioned you need to not just use the climate control but also start charging the battery. This can make a big difference in range by increasing the efficiency of the battery and reducing current draw from the battery heater (6KW) . Also 25C / 77F is a super high climate control, I would normally have mine set to 19C/66F with everyone wearing jacket and confortable but I have not made a really long trip like this in sub-zero temps. Perhaps there is a problem at highway speed and low temps which causes the foot wells to get really cold from wind drafting under the car? If I do take a trip in the future I'll load myself and passengers up with warm footwear

Btw, what speed were you hitting on the highway?

 

[Bebop]

This is my first Winter with my car and yeah I'm noticing drastic drops in range. As expected. I'm glad I got a 90D over the 75D, It's paying dividends now in super cold weather.

 

[Big Earl]

@Navsarin

Was there snow on the roads?

 

[Big Earl]

This is my first Winter with my car and yeah I'm noticing drastic drops in range. As expected. I'm glad I got a 90D over the 75D, It's paying dividends now in super cold weather.

This is my first EV winter, as well. I bought a Fiat 500e back in April and the summer range has been 85 to about 100 miles or a bit more. Now that it's winter, range has dropped to 55 to 70 miles, which is right on par with what I was expecting. Like Teslas, the 500e has a 6 kW cabin heater and a 6 kW battery heater (although I haven't seen it use more than 2 kW yet).

 

[Destiny1701]

@Navsarin

Was there snow on the roads?

No. It was dry roads but bloody cold! And I had chill mode on to avoid more drain.

 

[Destiny1701]

@Navsarin I'm afraid 30 minutes is not enough time to preheat when your battery is cold soaked. For best results, Id say you need at-least an hour and as others have mentioned you need to not just use the climate control but also start charging the battery. This can make a big difference in range by increasing the efficiency of the battery and reducing current draw from the battery heater (6KW) . Also 25C / 77F is a super high climate control, I would normally have mine set to 19C/66F with everyone wearing jacket and confortable but I have not made a really long trip like this in sub-zero temps. Perhaps there is a problem at highway speed and low temps which causes the foot wells to get really cold from wind drafting under the car? If I do take a trip in the future I'll load myself and passengers up with warm footwear

Btw, what speed were you hitting on the highway?

Makes sense. How does one preheat battery without the cabin? Separate setting?

Speed was 100-110km/h for 55 min each way.

Oh usually we keep around 20c but given the extreme cold, that temp setting was not working as well.’we only upped the temp to compensate for the floor being cold and feeling that slight colder draft at the floor level.

Next time double socks lol. Or just take our hybrid Highlander SUV with 8.5L/100km, 800km ‘real world ‘ range, very quiet, super well insulated cabin, reclining rear seats for kids to sleep on the way home...and avoid this hassle in super cold days lol. But...shouldn’t a 6 figure car be able to do all this standard?? I guess not? Lol.