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Cabin and Battery Warming before a long drive

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There have been several discussions on how to best prepare for a long drive. With the decreased range of winter travel, I wanted to ask opinions about what to do just before a long drive. So, if I range charge and want to heat the cabin, would that heat draw power from the plug or the battery? Is there an advantage to pre-cabin heating before I leave? Does pre-cabin heating warm the battery or should I do something else. I am concerned about a 215 mile round trip with some steep hills. The round trip will also include a few hours where my car is parked and not charging when I arrive. Thanks.
 
Preheating is highly recommended, in fact it's really mandatory before a long drive.

Cabin pre-heating warms the cabin AND battery if you start it from the remote phone App. If you are plugged in it will draw the power from the wall. This reduce the initial power draw quite dramatically, saving you a lot of range. Of course charging warms the pack, too, so it's not a bad idea to be charging just before you leave.

Don't turn on Range Mode while you are preheating the pack. Reportedly (not confirmed by me yet) it reduces the pack heating power too. Turn it on just before you start driving. It will help limit the heating power draw.
 
Preheating is highly recommended, in fact it's really mandatory before a long drive.

Seems like good advice. I went on a short trip to pick up some take-out. As I often do, I sit it in the passenger footwell and crank the heat to the floor to keep it warm. Temp HI, floor, full fans. I had just unplugged it, with a rated range of about 220 miles. The Energy app noted if I carried on in that manner for any length of time, my actual range would be closer to 90 miles.

Not completely applicable, but really shows that the heater makes a huge difference. Heat while plugged in :smile:
 
I've done several long-range winter trips. Here is my method, there are many variations.

  1. Charge to 90% the night before.
  2. Either set the car to "Max Range" charging and timed charging to start 2 hours before departure, or use the App to turn on "Max Range" Charging 2 hours before departure. These both assume a 40 Amp charge connection, adjust accordingly if you have more or less, but remember, even with 80-Amp HPWC, the taper starts at just a little more than "Standard" 90% SOC, and you will still need 1.5 hours or so.
  3. At 30-45 minutes before departure, use the App to turn on climate control and set the temperature to 5-10˚ F over what you normally like. This warms the cabin and stores a little heat in the interior thermal mass. Because the charge has already tapered, and the charging has warmed the battery directly and the cabin indirectly, this will not detract much from the charge effort.
  4. Enjoy the drive; you may even be able to leave the climate control off for the first 15-30 minutes and enjoy that heat stored in your interior.
 
Does this work if charging is complete? Let's say I had initiated and completed an 80% charge by 1am, and then used the remote app to heat up at say 7am. Would the above work?

Yes. That works, though I usually don't quite charge to the level I want to charge to and then when I get up I use the App to start charging and heating. Also I start the timed charging so that it will end just before I get up.
 
I would say preheat the car while on shore power and then be sure to set it to RECYCLE so your not heating outside air. I've found that if you remotely heat or cool the car it automatically goes to fresh air. You use lots less energy in recycle mode for both.
 
I've done several long-range winter trips. Here is my method, there are many variations.

This makes sense--nice, simple list. Thanks.

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I would say preheat the car while on shore power and then be sure to set it to RECYCLE so your not heating outside air. I've found that if you remotely heat or cool the car it automatically goes to fresh air. You use lots less energy in recycle mode for both.

Good point! Yeah, the app resets every setting to auto, whereas I want A/C and recycle. I keep hoping they'll fix this. Annoys me every time.
 
So I don't have a smartphone (or indeed a cellphone, really). Without the app, jerry33 advised turning the cabin heat on from the passenger side, and said it would then stay on after closing the door. Has anyone else tried this -- does this work for preheating?

It sounds like the only way to get the battery pack heater to go on in advance (while still on shore power) is to make sure that the car is charging for the hour or two immediately before departure. This is extremely finicky and sounds rather hard to do reliably. I think I'll call Tesla and make a request for a "preheat battery starting at XX:XX" feature, which should be pretty easy to do in software.
 
So I don't have a smartphone (or indeed a cellphone, really). Without the app, jerry33 advised turning the cabin heat on from the passenger side, and said it would then stay on after closing the door. Has anyone else tried this -- does this work for preheating?

I'm basing this on how you keep the heat on for the passengers when you exit the car. I haven't actually tried it as I have an iPhone, but I don't see why it wouldn't work the same even if there are no actual passengers.
 
I have seen no evidence that preconditioning on shore power heats the battery.

I still have the regen yellow line when I do it.

Yes, but in cold conditions with preheating the line is usually at 30kW regen when I start driving, in stead of 15kW limit with no heating. So I'm quite sure it does heat the pack some, but not fully. Hopefully this behaviour will be better controllable in future firmware/remote app. Also note that I currently only have access to 230V13A plug (3kW) so it may be that it's just not enough to heat both the cabin and the battery enough.
 
I have seen no evidence that preconditioning on shore power heats the battery.

I still have the regen yellow line when I do it.

Yeah, you won't get rid of that completely by preheating I think. For me, preheating is often the difference between no regen at all or 10-15kW of regen.

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Yes, but in cold conditions with preheating the line is usually at 30kW regen when I start driving, in stead of 15kW limit with no heating. So I'm quite sure it does heat the pack some, but not fully. Hopefully this behaviour will be better controllable in future firmware/remote app. Also note that I currently only have access to 230V13A plug (3kW) so it may be that it's just not enough to heat both the cabin and the battery enough.

When I preheat plugged in VisibleTesla usually report a battery draw of about 18A, compared to 27A when not plugged in. In total around 10kW. So the battery makes up the deficiency it seems.
 
If I don't preheat, there are two dashed yellow lines, one for power and one for regen. Preheating either gets rid of both or only leaves the regen one and it's 30 rather than 15.
 
I have seen no evidence that preconditioning on shore power heats the battery.

I still have the regen yellow line when I do it.

As others have said, preheating will not get rid of the limit line entirely; however it will significantly reduce the power limit, and decrease the time required to fully warm the pack. It will significantly reduce the pack heater power usage, which is a very good thing if you plan to drive a long distance.
 
You don't need a smart phone use a tablet or IPOD

So I don't have a smartphone (or indeed a cellphone, really). Without the app, jerry33 advised turning the cabin heat on from the passenger side, and said it would then stay on after closing the door. Has anyone else tried this -- does this work for preheating? It sounds like the only way to get the battery pack heater to go on in advance (while still on shore power) is to make sure that the car is charging for the hour or two immediately before departure. This is extremely finicky and sounds rather hard to do reliably. I think I'll call Tesla and make a request for a "preheat battery starting at XX:XX" feature, which should be pretty easy to do in software.
I use an IPOD but I suspect any tablet with wifi near by will work. I have wifi access at work and at home that's all I need.