I have the rear wheel drive so I know I need to get some nice blizzard tires or something on my car but I am wondering about the warm-up process for the car and what that consist of. We had our first snow in Utah today and I found very quickly the little icicle next to the battery on the screen and the mileage was a lot worse.
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My first winter
- Thread starter Shelby16
- Start date
Silicon Desert
Well-Known Member
You are going to see that icicle indicator a lot up there in the winter. Not sure what you mean by a warmup process. And yes, the mileage is going to go down in the winter.
I dont live in a place that generates very many of those "snowflake icon" days, but in general, if you want to warm the battery you can turn on the heat (pre condition the cabin) using the phone app.
Turning on the heat will also start to warm the battery. That isnt really "necessary" but can help with range and/or having regen available.
Since this is your first winter, you might forget that you can heat your car from inside the house, ensuring that you dont have to get into a cold car if you dont want to.
The temp here was 30F when I was about to leave so I used the Climate On function of the app - if you hit the defrost icon on the bottoms right, it will put the heat on high and turn on front and back defrost. I left it on 20 minutes. It wasn’t quite long enough because there was still a little ice on my door handle but the car was warm and windows were clear. The regen braking was decreased when I started to drive (which I expected) but I didn’t get it all back until I had driven on the highway (50-60mph with some slower areas in small towns) for 1.5 hours without stopping. I didn’t notice much impact to my driving from it, just watching the dots on the left side of the speed screen that turns green when regen is active.
Blue Express
Member
Most importantly, please do turn off your regenerative braking while driving on snowy roads.
This definitely isn’t necessary if you understand that regenerative braking is, in fact, a form of braking. Once you’re experienced with the feature, adjust your technique in slick situations as you would with any other type of braking.
There is some level of retraining reactions to match how a Tesla handles compared to an ICE car. Like in my previous car, a hybrid, there was some regen braking but it wasn’t as much as in the Tesla so it took a few minutes to trust full-on one pedal driving. And in my hybrid if I felt a little hydroplaning, I would slowly let off the accelerator. In the Tesla there’s more nuance to letting off the accelerator because a quick release means significant braking. But, because I am comfortable with one pedal driving now, I can react properly. If you’re driving in snow and ice, I would suggest going somewhere big and safe to practice (like an empty parking lot) and train your reactions so they are more automatic when you’re surprised by slick conditions. My dad used to pull on the steering wheel while I drove on ice to put me into a fishtail and through trial and error I created the automatic reaction I needed when I wasn’t in that parking lot. I could spin out while I learned and had room to make mistakes.
Here's a pro tip - schedule your car's charging so that it finishes in the morning (or whenever you regularly need to drive). This way the battery is warm from the charging process - heat that is otherwise lost to entropy if you charge the night before. Tesla reduces regen capability if the battery is cold. Your winter range will be much better if you have most/all of your regen available to you when you drive (unless you're doing a highway run with little traffic).
Some caveats - if you're charging from a 120V circuit (typical household outlet), the ambient cold might cancel out any temp gains from charging. With a 240V / 50A circuit, you should be fine unless you're parked outside in the elements. Again the heat loss to the environment might prevent battery temps from rising due to charging. Still, charging right before you drive gives you the best chance of improving your regen capabilities.
In my experience, using the HVAC heat doesn't raise the core battery temps much to see an appreciable difference in regen, so I would say that's an ineffective and inefficient way to condition the battery. But certainly do it if you want the cabin comfort before getting in your car.
The cabin heater is also a big drain on range. Lower your set point if range becomes an issue. Or keep it off if you can tolerate it, and turn it on briefly when the windows fog up.
I should probably know this, but does the ABS system reduce regen automatically if it detects slippage? I would assume it would have to, or ABS would be non functional on any car with significant regen.
Also, I know somebody suggested turning regen "off", but this is not possible unless you are in a M3P and it's in track mode, correct?
Using cabin heat from the app activates the front and rear motor stators as 3.5-4 kW (each) battery pack heaters. If you have Scan My Tesla or another similar app, you can see this in action. I preheated the car for about 15 minutes in 40ish degree weather, and the battery temp was up in the 60s by the time I drove (after cold soaking in 30-40 degrees for 15+ hours). You can also see the max regen parameter significantly increase as the pack warms.
I would advise for most people, you probably will use more energy significantly preheating the pack than you will gain from regen, so the only reason to do it is if you want to keep a consistent regen feel in different temperature conditions and reduce use of the friction brakes.
This is absolutely the best way EXCEPT departure time charging doesn't work properly. It's going to complete charging at 6AM regardless of when you set it for. I have not seen a reasonable explanation of why this is not configurable. Just makes a whole lot of assumptions which are irrelevant to me.
KingBozo
Member
Welcome toTesla in the winter, yup loss of range but managable and don't worry come spring you'll get it back.
that sucks. I've actually never tried that feature ever since it was released. Back before covid, I had a very regular commute, so I knew I needed to start charging at 4am to hit close to my charge set point. That worked well enough. So if the "depart by" feature is still busted, then just pick a good average start time.
Cool, didn't know that info was available via the APIs. will check it out. I have a LR RWD, so I assume I only have half the preconditioning power as you do... But yeah, 7-8kW total is a lot. more than my old Model S's dedicated battery heater I think. And that thing drained range like crazy with no way to shut it off.
Any advice on how to adjust my braking would be highly appreciated! I'm in a very similar situation with only having had my SR+ for ~6 weeks and just got to enjoy driving through the winter storm this weekend in Colorado while returning from Denver to Salt Lake. Having had the "pleasure" of spending way too many hours driving on essentially a sheet of ice, I found absolutely no way to use regenerative braking in standard mode safely (you can experiment a bit when you are by yourself on I-70). While regular breaking and driving on snow tires was absolutely fine, even the slightest regen would break the rear out which makes sense to me as I'm only "breaking" with my rear wheels while regular breaking involved all 4 wheels using ABS.
Just wondering, what causes most of the range loss? Is it the ambient temp when the car is not driving or when it's driving? All else being equal, would I see less range loss if I'm parking my Tesla underground at, say, 5 C (41 F) versus if I were parking outside with temps reaching -10 C (14 F) regularly?
Range loss when driving in winter is affected by many things. Among others:
- cold air is more dense, so more drag at speed
- winter tires are typically less efficient
- driving in water or snow adds to the drag
- Cabin heating consumes power, more than AC
- a cold battery will accept less regen.
The parking will help since the cabin and battery will have a higher starting temp.
@Greatday I don't understand. If you are on ice and have no traction, abs would also not slow you down. Could it be that you let go of the accelerator too quickly? Regen is a form of braking, and you don't want to change your acceleration /deceleration quickly when on a slippery surface.
- cold air is more dense, so more drag at speed
- winter tires are typically less efficient
- driving in water or snow adds to the drag
- Cabin heating consumes power, more than AC
- a cold battery will accept less regen.
The parking will help since the cabin and battery will have a higher starting temp.
@Greatday I don't understand. If you are on ice and have no traction, abs would also not slow you down. Could it be that you let go of the accelerator too quickly? Regen is a form of braking, and you don't want to change your acceleration /deceleration quickly when on a slippery surface.
