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Seen this couple of times now--and I know it's based on the GOM, which we all know is super-reliable.

Because it was hot again today, I turned climate control to Auto, which I rarely do (open windows are my preference), and that's how it was when I plugged in to charge. Battery got to full, I get in and start up, the center figure on the GOM is 235. Before I go anywhere, I turn off the Auto, turn off the A/C, and turn the fan back down to a low speed. The GOM center figure jumps to 256, which is about what I've been getting for a full charge typically.

I also noticed the other day at a stoplight and I was in Auto with the A?C and fans chugging along pretty well (temps in the 90s) that the speedo display was telling me I was using 2 kWh. I know typically at stoplights I'm 0.5 or 1.0 kWh.

So while I'm sure the A/C is much more efficient that ones of years and decades ago, I'm willing to assert that using the A/C likely amounts to about 20 miles per full battery, or 3-4% of the typical total electricity used. Sound reasonable? (Considering in my case I'll pretty much only use A/C when it is just too hot out for open windows to have any cooling effect.)
 

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In Texas due to extreme weather heatwave 100-105 f- with no rain or cold front-I'm experiencing use % on screen as follows driving 66%, climate control 29%, battery conditioning 5% , that's around 3.2 miles per kwh or around 190 max range per charge.
 

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So therefore despite what the GOM says it seems like the heavy use of AC = more like 70 to 80 miles loss of range per full charge.
 

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AC "cost" is dependent on travel speed and trip duration. On my daily commute on a "normal" hot day, it is around 8% of my usage for a 40 min drive. This is in conditions where I would normally be getting 4.5 miles / kWh, so this would equal around 22 miles of range loss from AC usage. On a long trip, same weather conditions at higher speeds it was 4% of my usage. On that recent highway trip, I averaged 4.1 miles / kWh, so 4% of total capacity would have cost me 10 miles of range.

Keith
 

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Just did a 120 mile trip in 100º weather, averaging 65 MPH with 72 MPH cruise most of the time, AC at 70º per spouse instructions, and registered .38 kWh/Mile vs. our usual .45 for local driving. GOM predicted 330 max at the start of the trip, and this morning with a full charge, 280.
 

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Just did a 120 mile trip in 100º weather, averaging 65 MPH with 72 MPH cruise most of the time, AC at 70º per spouse instructions, and registered .38 kWh/Mile vs. our usual .45 for local driving. GOM predicted 330 max at the start of the trip, and this morning with a full charge, 280.
These numbers don't sound right. Your miles per kWh decrease for local driving vs freeway driving? 0.38kWh/mile = 2.6 miles/kWh, while around town you get 0.45kWh/mile = 2.2 miles/kWh?
 

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One of the energy screens will tell you how your usage breaks down. In the summer with A/C on, mine usually says 90% for driving, 10% for cabin conditioning and 0% for battery conditioning. So, based on this screen, A/C "costs" about 25-28 miles on a full charge. And yes, it's worth it to me.
 

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Mine is usually around 9% so I'd rather stop 25 miles earlier than turn my seat into a slip-n-slide made of my own sweat. I'd say it's worth it! ;)

Mike
 

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I think your observations about mileage loss is correct. We have solar, so charging is now free for us. And we use A/C freely - even leaving it on while in the store. (Good case for getting solar)
 

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we use A/C freely - even leaving it on while in the store.
Since all our Bolt driving is local, we use the AC as needed, as long as needed. We have noticed leaving it on while grocery shopping, sometimes on a 90-degree day, upon getting back in the cool car, the range usually hasn't dropped at all, maybe a mile or two on a long stop.

jack vines
 

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I never care about A/C or heater use as long as I can make the trip. Since I never use my Bolt to travel beyond it's range, the A/C is never an issue. The heater gave me concern one time on one trip, so I killed it's use part way through and continued on with the the heated seats and wheel. I made it home with plenty of range in the tank, so probably overly conservative, but I've been a pilot a long time and it's just how I am.

The reason I waited to go electric was, I would only buy a BEV once I could use it without compromise in my daily driving habits and preferences. Finally the Tesla Model S came out and fit the bill, but there was no way I could afford it. Chevy Bolt to the rescue five years later! I had to stretch to buy the Bolt, but it's been worth it.
 

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My personal experience is that the GOM's estimate of the A/C sacrificing about 7% of the range is a reasonable average for an outside temperature of around 32C (90F), with the car not being heated up by the sunlight too much while being parked. On a hotter weather and/or a toasty cabin temperature, the A/C will work much more to get the temperature down and may end up using much more than 7%. I've seen the power consumption hover around 6kW during idle just after turning the car on at a parking lot during a hot day. It would slowly fall down to around 2kW after a few minutes.
 

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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.
 

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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.
The actual temperature setting where the heater will turn on to "complement" the A/C depends on the environment. I've seen it shift around 2 to 3C. I agree that this is ridiculously annoying, and in the end I, too, just resort to the LO setting and manually turn on/off the Heat-A/C button as needed. It's a lot more efficient that way.
 

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The actual temperature setting where the heater will turn on to "complement" the A/C depends on the environment. I've seen it shift around 2 to 3C. I agree that this is ridiculously annoying, and in the end I, too, just resort to the LO setting and manually turn on/off the Heat-A/C button as needed. It's a lot more efficient that way.

Yes. I have seen the point at which the heat comes on vary by a few degrees too. I wonder if the 2019, with separate buttons for AC and heat, does the same thing?
 

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I think your observations about mileage loss is correct. We have solar, so charging is now free for us. And we use A/C freely - even leaving it on while in the store. (Good case for getting solar)
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.
 

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Yes. I have seen the point at which the heat comes on vary by a few degrees too. I wonder if the 2019, with separate buttons for AC and heat, does the same thing?
Same problem with the 2019. I have experienced where both the HEAT and AC symbols were 'on' during 'auto' climate control and many times I have seen the car heat the cabin to the point that I wasn't comfortable on a hot day. I set it to 69 and fan speed 2 usually.
 

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Same problem with the 2019. I have experienced where both the HEAT and AC symbols were 'on' during 'auto' climate control and many times I have seen the car heat the cabin to the point that I wasn't comfortable on a hot day. I set it to 69 and fan speed 2 usually.
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?
 

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Good info as to Auto setting

As to actual HVAC usage, check the infotain page showing the distribution of energy - percent for driving, percent for HVAC, and percent for battery conditioning. Here in sunny humid Florida, my HVAC portion is typically 8-12%, but I get outliers such as low mileage days or times I park for errends and leave AC on (totally worth it to have car already cool)

Battery conditioning is generally less than 1% - very thin green slice that may be 1-2% some hot afternoons, but the number dips below 1% and is no longer displayed if I drive into the evening.
 
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