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Discussion Starter #1
I have my charging set to location based and it is usually all done very early in the AM.

Used the Pre-Conditioning to get the cabin temp up just before I jump in and go a few times.
I thought Pre-Conditioning uses "Charger Power" not battery power.
But my gauge tells me that power was from battery.

Am I correct / do I need a different setting ?
 

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I thought Pre-Conditioning uses "Charger Power" not battery power.
But my gauge tells me that power was from battery. Am I correct / do I need a different setting ?
Pre-conditioning the cabin while the car is still plugged in should use power from the wall. That is certainly my experience. I use Hill-top reserve, and immediate charging. I use location-based charging to ensure that I have a full charge when I am not at home. There should be no relationship between the type of charging and whether or not the car uses power from the wall. I preconditioned this morning with a Hill-top reserve range of 180 miles, and it did not change after heating up the car for 10 minutes. I did not check the "gauge" other than the range. I assume you looked at the circle that shows the relative amounts of energy used. I will look at that next time.
 

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I’m wondering if it works like a boat plugged into shorepower. The Bolt’s onboard charger accesses the plugged-in EVSE so as to replenish the battery at the same amperage as is being drawn from the battery due to the running of the preconditioning equipment ?
 

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The car will pull power from the wall and supplement with battery power. If you precondition long enough, any battery power that was used should get recharged. The heater in the car will pull 9 kW when first turned on, especially if it is very cold out. After a while, it drop to a more reasonable level, at which point the car will still pull the max from the wall, but split the available power between heating and recharging the battery.

I try to precondition for at least 15 minutes.
 

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Discussion Starter #5
^^^ Thank you.
My Pre conditioning has been 5 min / maybe up to 10. ..
so with all your info may be pulling from battery (and maybe some charger ) power but not enough time to recharge that amount of battery used.

I'll try it longer and see haw the gauges look.
 

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I'm assuming you are plugged into a Level 2 EVSE. How high does your L2 go in amps? If it (and the circuit it is on) goes all the way to 32 amps it should be able to supply 7.2kW to the car. So like devbolt pointed out in an earlier post the heater will pull 9kW early on giving you a slight deficit that the car battery has to supply.

If you are charging with a L1 EVSE or a L2 EVSE with less than 32 amps that deficit will be larger.
 

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^ max duration for pre-conditioning is 20min, you are allowed two pre-conditioning sessions- after that you must power on the Bolt to enable more pre-conditioning sessions.

No difference if you're plugged in or just on battery.
 

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battery conditioning and cabin pre-conditioning

I thought Pre-Conditioning uses "Charger Power" not battery power.
But my gauge tells me that power was from battery.
I switched my car on this morning to look at the gauge as we talked about. I did not pre-condition the cabin. As soon as I switched on the car, I could see the circle gauge ramp up and it read "battery conditioning". It finally settled on 25% battery conditioning. Note that confusingly, pre-conditioning of the cabin is a different thing from battery conditioning. Once I started to move, and very quickly, the display switched over to the driving circle I normally see, and now battery conditioning, as a fraction of total power being used, was less than 1% and quickly went to zero %, which is normal when driving. So, I have no idea what that 25% means. Is it a percentage of the charging power used to charge the battery? Maybe. However, I have reproduced what I think you are seeing, and I do not believe it has anything to do with Pre-conditioning, which heats the cabin, but is to do with battery conditioning, which heats the batteries in winter, and probably cools them in the summer. I did not try to observe the battery cooling this last summer, but I have observed the heating this winter.
 

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...Once I started to move, and very quickly, the display switched over to the driving circle I normally see, and now battery conditioning, as a fraction of total power being used, was less than 1% and quickly went to zero %, which is normal when driving. So, I have no idea what that 25% means. Is it a percentage of the charging power used to charge the battery?
The display that shows the circle graph also shows the total amount of energy used since the last full charge. Let's say that the amount of energy used is 0.5 kWh. The "25%" used for battery conditioning would be 25% of that amount, or 0.125kWh (125 Wh).

As soon as you start driving, of course the "energy used since last full charge" is going to start to climb rapidly - and as a result the proportion used by that battery conditioning is going to drop (assuming that there's no more battery conditioning). When you get up to 2KWh used, for example, the battery conditioning percentage will drop to just a few percent.
 

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Discussion Starter #11
Thanks all.
& I am sorry ... I was referring to Cabin Pre Conditioning.

So I am plugged in , but charging completed (L2 EVSE 32 amp) and now not in the location based time frame for my setting of Off Peak only.
I hit the Pre Condition on the "Key fob" on the My Chevrolet to heat up the car before I hit the road.

But I look to be using battery power to do that ... how can I set up or time correctly to use
 

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Thanks all.
& I am sorry ... I was referring to Cabin Pre Conditioning.

So I am plugged in , but charging completed (L2 EVSE 32 amp) and now not in the location based time frame for my setting of Off Peak only.
I hit the Pre Condition on the "Key fob" on the My Chevrolet to heat up the car before I hit the road.

But I look to be using battery power to do that ... how can I set up or time correctly to use
With your setup it is going to use some of the battery early on when the heater is pulling the max 9kW (greater than the 7.2kW your EVSE can supply) and won't recharge that used power from the battery since you are outside your charge settings time. If you did a 10 - 15 minute pre-conditioning cycle and you were still within your charge window it would have enough time to recharge the little bit of energy used from the battery.
 

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Cruze owner considering Bolt in Minnesota. Any thoughts anyone can share about the ability of the cabin to preheat in the 10 minutes or 20 minutes if this is ran twice?

What kind of outdoor garage temperatures are you starting at, and what temperature does the cabin reach in one 10 minute cycle? Is this feasible with outdoor temperatures of -5F in the garage?

I know the Bolt has heated seats and steering wheel as an option, I'm just trying to gather if preconditioning will get the car temperature to the point my family will accept it, and how much energy it might add per day to do it.

The few EV people I know in my area do not have Level 2 chargers at home, and I can't believe preconditioning the cabin with L1 would be that efficient of an idea..

Thanks-

Carbon02
 

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Based on my experience over the past week, the preheated Bolt warms up fairly quickly at temps as low as the teens. Subzero ambient is probably a much bigger challenge. However, the heater output when driving in cold temps is quite good - comparable to a small engine gas powered car. And the heated steering wheel - icing on the cake!
 

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Live from Minnesota with 7K+ miles after July delivery. Preconditioning after 5-10 minutes is plenty for this norske/swede half breed and for Big Momma too. Range was 300+ miles during our mild summer but has been down to almost half that now during our temps of +/- zero F outside. L2 charger in garage. Not sure what garage temp is but beer frig hasn't let the beer freeze yet but some of the bottle waters are a bit slushy and the refrigerator pickles have yet to freeze (vinegar freezing point = 28F).
 

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Cruze owner considering Bolt in Minnesota. Any thoughts anyone can share about the ability of the cabin to preheat in the 10 minutes or 20 minutes if this is ran twice?

What kind of outdoor garage temperatures are you starting at, and what temperature does the cabin reach in one 10 minute cycle? Is this feasible with outdoor temperatures of -5F in the garage?

I know the Bolt has heated seats and steering wheel as an option, I'm just trying to gather if preconditioning will get the car temperature to the point my family will accept it, and how much energy it might add per day to do it.

The few EV people I know in my area do not have Level 2 chargers at home, and I can't believe preconditioning the cabin with L1 would be that efficient of an idea..

Thanks-

Carbon02
Bolt preconditions in 20-min intervals, not 10 (that's the Gen 2 Volt). Recently with 34F outside temp and 2" of snow, my Bolt warmed up to 76F cabin temperature after roughly a single 20 minute period (it was 2 precondition requests combined, I aborted the first one due to n00b concerns about bubbling sounds from the heating/cooling loops in the Bolt). I have HVAC set to 76F, FAN at 4, and air directed only at the defroster vents. I was clearing the snow from the Bolt during this preconditioning.

I'm not sure how much energy was used since my battery was full and I didn't see any bars drained. Forgot to check myChevy app for % of charge.

You can precondition with L1. It won't restore all of the charge, but it will reduce the net loss. You just have to do the math yourself. How much energy would you need versus how much energy you can put back into the Bolt (don't forget to factor in you can't use the Bolt when charging). If you only travel say 90 miles a day and you assume a 3 mi/kWh efficiency, that's 30 kWh you'd need to recharge each day. At L1 charging ([email protected], or 1.44 kWh), that's 30 / 1.44 = 20.83 hrs to get full again.

You could also figure it backwards: say you can only charge at L1 (1.44 kW/h) for 10 hours per day (when you get home and sleep). So that's 10 * 1.44 = 14.4 kWh put back into your Bolt. So again assuming 3 mi/kWh efficiency, that's 3 * 14.4 = 43.2 miles of range every day.

If you can live with L1 charging, more power to you. For a while, I was living with slow L2 charging ([email protected] = 2.88 kW/h) and was operating a deficit throughout the week for my 100 mile commute. By end of the week, I'd have 60% fully charged before going to work but this was fine: I made up the charging over the weekend.
 
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Reviving discussion of preconditioning as winter is coming...

 

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I have not tested it, but I understand that the free/included 5 year OnStar Basic allows me to precondition the car from far away via the internet, right? So, I can trigger preconditioning throughout the day to keep the battery conditioned while in the parking lot, right?
 

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Cruze owner considering Bolt in Minnesota. Any thoughts anyone can share about the ability of the cabin to preheat in the 10 minutes or 20 minutes if this is ran twice?

What kind of outdoor garage temperatures are you starting at, and what temperature does the cabin reach in one 10 minute cycle? Is this feasible with outdoor temperatures of -5F in the garage?

I know the Bolt has heated seats and steering wheel as an option, I'm just trying to gather if preconditioning will get the car temperature to the point my family will accept it, and how much energy it might add per day to do it.

The few EV people I know in my area do not have Level 2 chargers at home, and I can't believe preconditioning the cabin with L1 would be that efficient of an idea..

Thanks-

Carbon02
 
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