Morning charging trick

[Liz G]

I hate the cold. That's why one of my favorite things about the S is the ability to preheat the cabin. But this unfortunately pulls power from the battery reducing my range.So to prevent this I use the following trick. In the morning I use the app to start heating my car. Then I walk out to the garage, unlock the car, pull the UMC cable out and then put it back in. The car starts charging again and still continues to heat the cabin. This appears to offset any lose of range from heating the car.

 

[FlasherZ]

Want a slightly better way?

Use the app to start pre-heating the cabin. Then use the app to switch to range mode, then switch it back. No need to head to the garage. It'll cause the car to start charging again (unless you're right at 240 mi.)

 

[Liz G]

Thanks. One less trip out into the cold.

 

[Doug_G]

I can confirm FlasherZ's technique works - I used it yesterday before leaving the office.

 

[raptorweb]

Today I noticed that when I started preheating in the garage with it still plugged in it was pulling some power via the outlet. I need to do some more investigating because it was only about 250 watts and I would expect more.

 

[aaron.s]

All -

Since I park my car outside, I've been loosing about 15 miles overnight from my standard charge because of the cold. Yesterday when I started to preheat the cabin, when I checked the app 20 minutes later, the car had started charging automatically.... No having to switch to range mode and back again or unplugging/plugging back in....

Aaron

 

[widodh]

I was told that it would draw power from the outlet instead of the battery when plugged in, now it seems like it doesn't?

Wouldn't be that hard to fix though, just start the charge and heater at once.

You shouldn't have to be a whizz-kid to figure that out.

I also would like it to preheat the battery, so when I leave my car is fully charged with the maximum of electrons in the battery for max range.

This is just programming work, nothing else.


Sent from my phone, so my apologies for typos.

 

[aaron.s]

I was told that it would draw power from the outlet instead of the battery when plugged in, now it seems like it doesn't?

Wouldn't be that hard to fix though, just start the charge and heater at once.

You shouldn't have to be a whizz-kid to figure that out.

I also would like it to preheat the battery, so when I leave my car is fully charged with the maximum of electrons in the battery for max range.

This is just programming work, nothing else.


Sent from my phone, so my apologies for typos.

widodh

A few days ago I set up a power monitor on the 50amp circuit for my Model S. A little while ago - I started a preheat (at 70 degrees - 21 degree outdoor temp) and noticed the energy monitor instantly displayed the circuit was drawing 660 watts. About 5 minutes later, the car started to charge again since I had lost about 15 miles of standard range overnight (my car is parked outside).

So that clearly shows it draws (at least some or all) power from the AC power....

Aaron

 

[raptorweb]

Here are the results of a test I ran on it this morning. Pretty much the same as Aaron noted.

Point A - Preheating started using about 240W
Point B - After about 8 minutes it started charging using the normal about 9200W
Point C - Cabin reached the request temp and I shut off the heating

The charging continued for about 8 mins after this when it was at a completed standard charge.

 

[FlasherZ]

The reason I use the app to start charging immediately is that I don't pre-heat for more than 15 minutes or so -- unlike my ICE, the cabin is generally at a reasonable temp at 10-15 mins. Restarting charging immediately helps it get topped off by the time I leave.

 

[widodh]

widodh

A few days ago I set up a power monitor on the 50amp circuit for my Model S. A little while ago - I started a preheat (at 70 degrees - 21 degree outdoor temp) and noticed the energy monitor instantly displayed the circuit was drawing 660 watts. About 5 minutes later, the car started to charge again since I had lost about 15 miles of standard range overnight (my car is parked outside).

So that clearly shows it draws (at least some or all) power from the AC power....

Aaron

Thanks for the information! In the cold this could save a lot of power at the beginning of your trip since you don't have to use battery power for heating the car (or cooling in the hot).

 

[aaron.s]

Thanks for the information! In the cold this could save a lot of power at the beginning of your trip since you don't have to use battery power for heating the car (or cooling in the hot).

Absolutely! thats the main reason - not really doing it for the cabin preheating - its just an added benefit to having a toasty interior and a warmed up battery pack.

Today I let it do this for about an hour and I had no regen limits! Warm battery pack so no loss of range.

Aaron

 

[Doug_G]

Absolutely! thats the main reason - not really doing it for the cabin preheating - its just an added benefit to having a toasty interior and a warmed up battery pack.

Today I let it do this for about an hour and I had no regen limits! Warm battery pack so no loss of range.

Aaron

At what temperature? At -10C and below I've never been able to get the regen down to zero, even with 70A charging.

 

[aaron.s]

Doug

Low 20's F this morning. I was surprised I had no regen limits....

Aaron