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So when I installed my home EVSE, I also installed a little, inexpensive, electric gage. GDank warned me to not trust such things, but it's giving me solid numbers. I am beginning to trust it. At the very least, it's not far off.

So today, I checked everything... all good, charged up, ready to go... and then I reset the gage and started the pre-conditioning... heat on auto, seats and steering wheel on preheat. Then I looked at the gage.

By George, it was drawing nearly 30 amps! That current began dropping pretty quickly but slower with time, so some sort of asymptotic curve. After about 5 minutes, it was down around 20 amps. By the time I went to drive the car, perhaps about 15 minutes later, my little gage had shown 0.86 kWh had been used up in pre-conditioning alone.

So... I confirm what others have said in various threads here... heating up the cabin really does draw a lot of current. It's no surprise to me now when I lose so much of the battery when I jump in to a cold car and just get going.

Here's a picture from, perhaps, 10 minutes into the preconditioning: 15 amps at single phase 238 volts with 0.69 kWh drawn.

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You’ve got a thousand pounds of battery mass to heat up. That’s gonna abuse a few electrons.
 

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You’ve got a thousand pounds of battery mass to heat up. That’s gonna abuse a few electrons.
does the preconditioning routine do anything to the battery (directly) or is it just for cabin heating/cooling?

btw. With our mild mid day weather (40-60F/ 5-15C) and preconditioning I’m now getting 33.5-35kWh/100mi for longer drives that generally include going up/down hills and a mix of highway/backroads. I think when the weather gets properly warm should be able to beat EPA range!
 

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I've never found a consistent message in this forum about whether or not the preconditioning directly heats the battery. It seems that the general consensus is that it does not.
 

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I only found this out today. The power drain from heated seats and windscreen clearing is immense! I tried it whilst charging from a 22kw post (11kw 16A draw obviously) and the charge range dropped from 21mph to 3mph 😲.

That taught me pre-heating while on charge seems to be the sensible option.
 

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perhaps about 15 minutes later, my little gage had shown 0.86 kWh had been used up in pre-conditioning alone.
That's about right. 0.86x4=3.44kw/h which is very reasonable for the cabin heater. On a cold day while driving I imagine it could easily go higher.
 

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I can confirm that the pre conditioning definitely does not heat the battery. Just the interior of the car.

It does draw a fair bit of juice!
The battery would take a lot more and should be kept warm while plugged in once PS gets their act together with that aspect of the system.
 

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I only found this out today. The power drain from heated seats and windscreen clearing is immense! I tried it whilst charging from a 22kw post (11kw 16A draw obviously) and the charge range dropped from 21mph to 3mph 😲.

That taught me pre-heating while on charge seems to be the sensible option.
Windshield heating can be similar to heating the car and draw up to 7-8kw. Seats on the other hand use very little. The average seat heater uses about 50w. That's only 0.2kw if you crank all 4 of them.
 

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That's about right. 0.86x4=3.44kw/h which is very reasonable for the cabin heater. On a cold day while driving I imagine it could easily go higher.
Jeez, I can heat my whole house for less energy than that on my..... heat pump... hmmmm.....

using 2.8kWh for 3,000 sqft feet right now in 35 degree (F) weather.
 

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It will indeed pull 30A on startup. It then ramps down after a min. Over the 30mins It takes around 2kW (so 4kWh) to heat up. This is the same roughly as a 3kW electric fire at home heating a small room.

Picture of the car charging as I turn the pre-heating on:-

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Car is charging at 0mph but still pulling 31A
 
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Jeez, I can heat my whole house for less energy than that on my..... heat pump... hmmmm.....

using 2.8kWh for 3,000 sqft feet right now in 35 degree (F) weather.
I would assume you are maintaining your house at a comfortable temperature with 2.8kW. Probably your house is insulated (though in SF, that’s not a guarantee!) so the power requirements are low.

It would take more power to raise the temperature of a 35°F cold-soaked house to 68°F. A cabin in Tahoe, for instance.

I love my efficient household heat-pump here in Maine. I wish my Void... uh, my 2... whatever... had the option to have one.
 

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Bjorn Nyland made a test comparing a Model 3 with heat pump vs one without. It made a huge difference keeping the car at 21C in 2C ambiant. So yes, cabin heating uses a lot of energy.
 

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Jeez, I can heat my whole house for less energy than that on my..... heat pump... hmmmm.....

using 2.8kWh for 3,000 sqft feet right now in 35 degree (F) weather.
The car does not have a heat pump. You would use a lot more if your 2nd stage heat kicked in. Think of your 1000w hair dryer. How many of those might you need blowing in the car to warm it up. That should give you a sense of why it takes so much energy.

The reason EVs almost all come with seat and wheel heaters is because they provide very cheap heating of your bottom and hands. Even less expensive EVs have rear seat heaters. It's not because the cars are trying to be "up-market".
 

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The car does not have a heat pump. You would use a lot more if your 2nd stage heat kicked in. Think of your 1000w hair dryer. How many of those might you need blowing in the car to warm it up. That should give you a sense of why it takes so much energy.

The reason EVs almost all come with seat and wheel heaters is because they provide very cheap heating of your bottom and hands. Even less expensive EVs have rear seat heaters. It's not because the cars are trying to be "up-market".
Yeah, my initial comment I suppose was poorly phrased sarcasm for the fact that the P2 doesn't offer a heat pump, yet the XC40 does. It annoys me that on the XC40 it is an option, meaning it can likely be swapped in easily on the production line, but we (seemingly) will have no option to retrofit on to the P2.

I have ultra efficient Mitsubishi units and a well insulated house for sure in my mountain house where I am escaping the city, and all people, so it makes sense that it's not using too much to maintain but still surprises me a bit how much the car needs just heat the air in the cabin.
 

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All EV's should have an option of a heat pump. Should not be standard as many places can get away without it.

Polestar not including it I think was down to time and what they wanted to deliver .. ie. a Froot or Frunk that wasn't 1" deep.
 

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All EV's should have an option of a heat pump. Should not be standard as many places can get away without it.

Polestar not including it I think was down to time and what they wanted to deliver .. ie. a Froot or Frunk that wasn't 1" deep.
I wonder if the heat pump shouldn't be standard (since it provides sufficient heat for most climates) and make the radiant heater optional for those of us in colder climates.
 

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I wonder if the heat pump shouldn't be standard (since it provides sufficient heat for most climates) and make the radiant heater optional for those of us in colder climates.
If I was in the south of the EU spain/Portugal winters go down to 10degs C. For the rest of the year you'd be 15deg min. At this point you are carrying around extra weight the rest of the year and paying extra cost for the car for almost no benefit.
 
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