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Preconditioning doesn't pull power from the wall?

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We've had 40 degree weather the past couple days and today was the first time I remembered to hit the cabin heat before heading out to the vehicle. I checked my wall charger to see what the Rivian was pulling from the wall and it said 0.00 kW. I'm a bit disappointed to see that they are using power from the battery instead of the "free" power from the wall to do it, every other EV I've owned has turned on the charger to buffer out using the energy already stored into the battery as much as it can.

Caveat is that I'm not on the 2022.35.3 patch so I don't know if they've made an undocumented change for this already.

I'd also like to see an option for enabling the seat and steering wheel heaters automatically with a preconditioning cycle as they were both still quite cold when I sat down after 10 minutes.

And, I'd also like to see Rivian support scheduling departure/climate timers like Polestar has done in the 2. You can set a time of departure from either the center console or within the phone app on the Polestar. Last winter I always had a toasty warm vehicle to get into in the morning and never had to think about it.
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I am going to guess.... Likely the heater always runs off the battery and if you let it go for a few minutes the charger would kick into add the charge back? This is totally a guess....
 
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I am going to guess.... Likely the heater always runs off the battery and if you let it go for a few minutes the charger would kick into add the charge back? This is totally a guess....
Every EV I know of runs the heater off the battery, but they engage the chargers to try to keep the power being pulled out of the battery at zero.
 
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Every EV I know of runs the heater off the battery, but they engage the chargers to try to keep the power being pulled out of the battery at zero.
I guess that is what I am saying... When the battery charge changes enough to register not fully charged the charger will kick in... That would not be instantaneous.... Again, I am just guessing since I do not have my R1T yet...
 

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I have found that if imy truck is currently charging it uses the charger (my miles added rate drops on the app). If you have reached your limit on the charge cycle and not actively charging, it will pull from the battery. Mine just updated to the new software last night so it could have changed...?


My MachE had a departure schedule that was a great feature for setting the car climate. I am hoping they will add something similar, I assume they will at some point.
 

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I have found that if imy truck is currently charging it uses the charger (my miles added rate drops on the app). If you have reached your limit on the charge cycle and not actively charging, it will pull from the battery. Mine just updated to the new software last night so it could have changed...?
This is probably how it's configured, but I'm saying it's wrong. It's introducing additional energy losses using stored energy instead of pulling from the wall charger. There's no benefit to preconditioning while plugged in and actually doing so probably hurts the range even more this way.
 

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This is probably how it's configured, but I'm saying it's wrong. It's introducing additional energy losses using stored energy instead of pulling from the wall charger. There's no benefit to preconditioning while plugged in and actually doing so probably hurts the range even more this way.
It would warm the battery up a bit, which would help in the cold.
 
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It would warm the battery up a bit, which would help in the cold.
It's an insignificant amount of warming for the battery, usage is really low compared to actual driving.
 

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I am going to guess.... Likely the heater always runs off the battery and if you let it go for a few minutes the charger would kick into add the charge back? This is totally a guess....
This is how the Rivian works from my observations. I’m petty happy with it too. I’ve found that it will start to top the battery back off pretty quickly. My etron on the other hand, even if you precondition it 15 minutes before you leave, it will probably never get to the point where it starts to pull power from the wall to maintain the battery SoC. The Rivian will kick in and out and in and out to maintain the charge setpoint.
 

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This is probably how it's configured, but I'm saying it's wrong. It's introducing additional energy losses using stored energy instead of pulling from the wall charger. There's no benefit to preconditioning while plugged in and actually doing so probably hurts the range even more this way.
While I understand what you mean, is it also possible that even in other EV's it's really still pulling from the battery and not technically the wall? I'm no electrical engineer, but I would surely assume there would be no reason to run electrical circuits to be able to power things from both the battery and from the incoming power from the charge port. That would seem incredibly wasteful. Everything runs through the battery.

My eTron was similar to what you describe. If you were running preconditioning the charger would also run, but technically speaking the HVAC was pulling from the battery which was backfilled by the charger. So then the question would just be at what threshold does Rivian start requesting power from the EVSE. From what I've seen, it takes a percent or two before it will start charging again.

I guess the tip off might be whether the EV says it is charging or not while powering the conditioning. If my eTron was at the set SoC, and I started preconditioning, the EVSE would start up again and the vehicle would say it was charging. This is what suggests to me that as I described, everything flows through the battery. If another EV is running heating/cooling but otherwise looks like it is unplugged, then perhaps it is wired to be able to power those things directly through the charger.
 

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I have found that if imy truck is currently charging it uses the charger (my miles added rate drops on the app). If you have reached your limit on the charge cycle and not actively charging, it will pull from the battery. Mine just updated to the new software last night so it could have changed...?


My MachE had a departure schedule that was a great feature for setting the car climate. I am hoping they will add something similar, I assume they will at some point.
Even while charging, it is pulling from the battery. The miles/hour charge rate is merely showing the net effects of all the sources/uses of energy impacting the battery SoC. In other words, the miles/hour is just reporting the net change in SoC per unit of time, converted to miles of range.

They are planning to add the departure charging timer by EOY, at least as of a couple months ago. Regardless of timing, it's on the nearish term roadmap.
 

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I think it can’t match the charging rate to the battery draw. If I have the truck set to charge at 8kW, and the heater is using 1kW, the truck can’t reduce the charge rate down to 1kW to backfill the heater draw. So the heater draws down the battery a little until the charging kicks in at 8kW. The 8kW charging cycles on and off to keep the battery at approximately the desired SoC, but not exactly.
 

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This is probably how it's configured, but I'm saying it's wrong. It's introducing additional energy losses using stored energy instead of pulling from the wall charger. There's no benefit to preconditioning while plugged in and actually doing so probably hurts the range even more this way.
It will not introduce more losses (I am a electrical engineer and taught)... The heater is going to run on DC so the conversion from AC to DC (which is lossy) has to happen anyway. The storage process really is not lossy (as far as I know).. It also simplifies control and wiring I am sure
 
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I think it can’t match the charging rate to the battery draw. If I have the truck set to charge at 8kW, and the heater is using 1kW, the truck can’t reduce the charge rate down to 1kW to backfill the heater draw. So the heater draws down the battery a little until the charging kicks in at 8kW. The 8kW charging cycles on and off to keep the battery at approximately the desired SoC, but not exactly.
Definitely not what I saw this morning. It never engaged the charger. I charge to 85% and by the time I got out of my sub, it said 84%. Maybe if I had let it keep going for another 15 minutes it might have kicked on the charger, but it really should be proactive and attempt to zero out consumption at least.
 
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It will not introduce more losses (I am a electrical engineer and taught)... The heater is going to run on DC so the conversion from AC to DC (which is lossy) has to happen anyway. The storage process really is not lossy (as far as I know).. It also simplifies control and wiring I am sure
You're not a chemical engineer then. Everyone should care because cycling the battery is additional wear on it.
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