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If you use Torque Pro, you will see that when running the AC, if you turn it down to 69 F or below, it runs the AC compressor. But if you set it a bit higher, in addition to running the compressor, it turns on the heat! The resistance heat is using as much or more energy as the AC compressor, I guess to dehumidify? I have taken to running the fan on 4, and turning the temperature all the way to LO...61 F, if I recall correctly. I then turn the heat/AC off and on manually to maintain the temperature I want. Pretty unbelievably stupid design.
Agreed. Chevy got a lot of things right on the Bolt, but missed on this one.
 

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^ so you guys are saying that setting the A/C temp to 72 makes the resistive heating element activate even if the OAT is 90deg?
 

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^ so you guys are saying that setting the A/C temp to 72 makes the resistive heating element activate even if the OAT is 90deg?
Yup. The exact temperature setting it happens at varies...depending on humidity, I am guessing. My wife just sets the temperature that feels good, and doesn't worry about energy consumption. In two years, she has never driven far enough, by herself in a day, to worry about range. I'm a compulsive nerd, so I pay attention.
 

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Yup. The exact temperature setting it happens at varies...depending on humidity, I am guessing. My wife just sets the temperature that feels good, and doesn't worry about energy consumption. In two years, she has never driven far enough, by herself in a day, to worry about range. I'm a compulsive nerd, so I pay attention.
I've been like your wife... I haven't cared because at 80 miles per day and free charging at work, no worries. Now in the next two weeks I'll start my weekly trek across Michigan for college football games. I've learned I can't make the round trip on a full charge (which is usually 225 miles of range - all highway driving 70 MPH speed limit) and will be looking for ways to charge on route as destination charging might not be doable based on the sheet number of people trying to park for the game. I'm hoping the EA site that's not too far out of the way (additional 20 miles) will open up and make things easier and allow for AC use the whole trip if needed.
 

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I am not surprised it does it on auto. They are dehumidifying the air because it feels better. I never use the auto button, but it does both anyway, presumably because the button is for both. Does your heat come on if you only push the AC button?
No, not with my experience so far. This is my first summer in the Bolt. I took delivery in November and up to now I have been on AUTO the whole time. I did turn off the auto dehumidification settings day 1. If I set the car to 70, it sometimes turns the heat on....sometimes with the AC also on, sometimes just the heat even though it's warm outside. So, if I'm on AUTO now, I set it to 69. But then after a bit I get too cold so I hit the fan down button and find myself now set to 69, AC on, fan speed 2 or 3.
 

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You'd have to have a pretty hefty solar system to drive the Bolt and consider your charging for free. I have a decent amount of panels on my roof (37), which in sunny central California produce a total of 14 KWh per day during summer months. Using 3.9 miles per KWh, a full day of solar energy will get me about 54 miles of range. However, when I crank on the AC in my Bolt, my number drops to about 3.2 KWh of range, giving a warm summer days range of 45 miles. This presumes I do not use any of my solar generated electricity to power anything else in my house, which of course is not the case for the vast majority of us.
A company near me has a lot of solar cells and they have a bunch of L2/L3 EVSE .... a sign says they use the solar power to run the chargers. Of course no detail.
 

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I hadn't considered the Bolt would run the heater with AC to blend the temperature, but that makes sense considering the system is borrowed from ICE. In an ICE, the car blends heat and AC to achieve the desired temperature.

I believe the Prius has a variable speed AC compressor, so it doesn't run heat to achieve the desired temperature. I'll have to pay closer attention to how it behaves next time.

ICE compressors are either on or off, usually controlled by a clutch.
 

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I was experimenting w/the A/C yesterday on the way home from work... it was 94deg and humid outside so it was a good time to play with the system.

Looking at the dashboard wattmeter (while stopped at traffic lights) I saw no difference in electrical consumption when switching the A/C temp setting between 72f and 61f... draw was between 4-5kWh.

I did notice however that the fan speed gets boosted somewhat if you dial the A/C temp setting down from 61f to LO.
I guess that's GM's way of giving you max output. Didn't know that one till yesterday, I have owned my Bolt since 4/2017.
 

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I hadn't considered the Bolt would run the heater with AC to blend the temperature, but that makes sense considering the system is borrowed from ICE. In an ICE, the car blends heat and AC to achieve the desired temperature.

I believe the Prius has a variable speed AC compressor, so it doesn't run heat to achieve the desired temperature. I'll have to pay closer attention to how it behaves next time.

ICE compressors are either on or off, usually controlled by a clutch.

The Bolt has no components from their ICE AC. It is a EV specific, variable speed, 400 volt unit, bolted to the motor/gearbox housing. I see it go up and down in rpm, on Torque Pro, all the time, and you can hear the rpm change too. The heat is being turned on because the system uses a humidity sensor, as well as a temperature sensor.
 

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Looking at the dashboard wattmeter (while stopped at traffic lights) I saw no difference in electrical consumption when switching the A/C temp setting between 72f and 61f... draw was between 4-5kWh.
Sadly, the DIC watt meter does not show all energy use. You need Torque Pro to see the actual energy use.

The Torque Pro, AC PID shows rpm, but not watts. I think the maximum wattage of the compressor must be under a kW, so the dash meter doesn't really reflect it. The heater, which can hit 7.5 kW at max, definitely shows up on the dash meter.
 

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At a stoplight w/o the A/C running the DIC shows 0 watts draw, I turn on the A/C and it shows 4-5kWh draw when set to "LO"or 72deg. It seems the DIC is displaying the results of activating the A/C system.

Does the resistive heater circuit have a known PID?
 

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You'd have to have a pretty hefty solar system to drive the Bolt and consider your charging for free. I have a decent amount of panels on my roof (37), which in sunny central California produce a total of 14 KWh per day during summer months. Using 3.9 miles per KWh, a full day of solar energy will get me about 54 miles of range. However, when I crank on the AC in my Bolt, my number drops to about 3.2 KWh of range, giving a warm summer days range of 45 miles. This presumes I do not use any of my solar generated electricity to power anything else in my house, which of course is not the case for the vast majority of us.
We have 40 panels on our roof making 7KW, and up to perhaps 45Kw per day of output in the summer. Our house uses maybe 12Kw per day, leaving 32KW, or 125 miles per day to feed our 2017 Bolt.
 

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Does the resistive heater circuit have a known PID?
Yes. There is a PID for the 7500 watt max cabin heater, and one for the 2800 watt, if I remember correctly, battery heater. I wish they had a PID for AC compressor watts, instead of rpm, which I could give a fig for. It basically tells me the AC compressor is on, and how hard it is working, but no actual energy number.
 

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^ thanks!

OT, but does the 7500 watt cabin heater vary it's load or is simply bang on/off according to the circulating water temp?
 

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The AC compressor, cabin heater, and battery heater all vary their load.

I just went out and checked our 2017 LT again to make sure I wasn't making this up. I turned on the car, lights turns off, AC/heat turned off, fan turned off, center screen blacked out on low energy setting. The DIC, and Torque Pro showed 0.5 kW energy use. I woke up the center screen, and both showed 1.0 kW. With the AC/heat set to LO, fan on 5, they both showed 1.5-2.0 kW used. the cabin heat did not come on. Your Bolt is turning on the cabin heater. Either you are using the Auto button, or you have not turned off the auto defog settings.
 

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Since I checked out the AC and heater earlier, it has started raining pretty heavily, and the temperature has dropped 5 F.

I just went out in the garage and tried the same setup, but with AC/heat set to HI instead of LO. The heater went on as I expected, and the energy use shows up on the DIC...but the AC also came on. Nothing I did would make the AC stop, except turning off AC/heat. So the humidity sensor works even without using Auto, and with auto defog turned off.
 

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It's too simplistic to just say it uses up 20 miles of range. It's all dependent on outside temp, solar intensity, your drive time. As an example, my new Bolt had been spending its time (before purchase) basically preconditioning the battery, running A/C at 115F outside temp, and going out on test drives... Driving: 43%, climate control 42%, battery conditioning 15%. So it was reporting 160 miles range with 75% battery...

After purchase on Friday, it's been running A/C while charging, used to practice parallel parking with outside temp at 105F, my range now is 150 miles with 75% battery...

:)
 

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I thought about it and it appears that the A/C (in over 100 temp) uses probably 2-3 KWh per hour.

I found this other thread talking about energy use of the A/C.
 

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I just went out to the car to check out AC energy use in our 2017 Bolt LT. I turned on the car, I set AC/heat off, fan off, lights off, dash lights turned to low, center screen to low energy setting. The power meter to the right of the DIC screen showed 0.5 kW. Torque Pro showed 0.3 amps x 367 volts = 110 watts.

Min power.jpg

I then turned the fan to 8. The DIC showed 1 kW. Torque Pro showed 0.9 amps x 367 volts = 330 watts.

I turned the AC/heat on at LO/60F. The compressor went over 2900 rpm, and Torque Pro showed 6.3 amps x 367 volts = 2312 watts briefly. The DIC showed 2 kW. I tried to catch it but got...

max AC.jpg

After several minutes of gradually reducing compressor rpm, and energy use, the compressor was at 20xx rpm, and energy use was bouncing around 3.9-.4.5 amps x 367 volts = 1300-1650 watts. DIC showed 2 kW.

After several more minutes compressor rpm was at 19xx, and energy use sat at 3.9 amps x 367 volts = 1431 watts. The DIC showed 1 kW.

Set to higher temperatures, and more humid conditions, the heater can come on too, and raise the energy use.

Oops! Brain fade. That is high voltage amps, so must be multiplied times pack voltage. Let me try again....now edited.
 
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