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Discussion Starter #1
I've read a couple of posts about the A/C not using up that much energy. It has not been very hot here yet, and i keep the A/C on 75 with the system in Eco mode, and I still get "-5" on the usage from climate control. What's the real dope?
 

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I've read a couple of posts about the A/C not using up that much energy. It has not been very hot here yet, and i keep the A/C on 75 with the system in Eco mode, and I still get "-5" on the usage from climate control. What's the real dope?
The energy usage screen will punish you with a -5 rating if you use any climate control beyond the blower, even that will result in a -2.5 rating. Ignore it. The true measure is when you have finished your daily drive and view the pie chart of energy usage, HVAC will probably be 4 - 8 % for AC. This is not bad compared to HVAC electric heat where you can consume upwards of 30% of the battery charge just heating the cabin. If you watch the energy usage on the DIC Classic Enhanced screen, when the Volt is parked and the AC is running with Economy setting, you will see the power used fluctuate from 1 - 3kw. Remember that the Volt always starts out using 0.5kw just sitting in Park when powered on.
 

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For other people's sake please use the AC and don't worry about how much energy it takes up. With your previous ICE vehicle you probably turned on the AC as needed and didn't give it a second thought. But now you have all this on-board telemetry taunting you to twiddle with things in terms of efficiency, but in the end friends and coworkers do not want to smell your BO.
 

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I was guilty of obsessing over the Volt's reported energy use via the on-board displays. I have learned to ignore them for the most part because ALL CARS USE MORE ENERGY when operating the AC, even ICE vehicles. The problem as I see it is GM gives you a more granular view of it than any ICE vehicle could, that's probably because they are measuring consumption purely against the battery and not the TOTAL energy available on board i.e. battery SOC PLUS amount of GAS in the tank.

Stop worrying and be happy.
 

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Discussion Starter #6
Trust me when I say I will continue to use AC and heat for comfort. I'm too old to think otherwise. But I agree that it's the information overload that gets you thinking about it.
 

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If your trip will be barely within the Volt's EV range, then you can worry about using the AC. Otherwise enjoy setting the AC to your comfort and not worry about it. Its effect on EV range is small, especially when you use eco mode on auto.
 

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Trust me when I say I will continue to use AC and heat for comfort. I'm too old to think otherwise. But I agree that it's the information overload that gets you thinking about it.
A couple giant pieces of electrical tape can fix that :)
 

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Electricity users in the Volt:
1. Traction motor (tens of KW up to max power rating)
2. Heater (high single digits KW)
3. AC (low single digits KW)
4. Everything else combined.

I tend to drive with AC off, even in gassers, just what I prefer (only around town, higher speeds use AC due to noise). AC will drop your range, but not as bad as heat.
 

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I really would love to know from GM just how more efficient the AC is than the heater. One of the primary facts people keep forgetting is the temperature differential when using heat is usually far greater than when cooling. Taking it down from 100 to 75 is 25 but heating to 65 from 40 is not where most people see large numbers but instead from down near freezing and usually back to 70 or so.

Regardless, if your ending your commute with miles to spare, especially over ten, then it really does not matter.
 

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Discussion Starter #11
On the flip side of this, the heater is supposed to take up a lot of battery power, while the seat heaters do not. What is the difference? Each of them works with a coil, inductive heater. The only difference seems like the blower motor.
 

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On the flip side of this, the heater is supposed to take up a lot of battery power, while the seat heaters do not. What is the difference? Each of them works with a coil, inductive heater. The only difference seems like the blower motor.
The seat heater and steering wheel heater are powered by the 12V system. They use 100 - 200 watts. The electric heat coil is powered by the 400V traction battery. The heater coils, there is more than 1, are immersed in coolant. The coolant circulates through the heating and cooling loop. The coils can draw up to 9kw, that is like (7) 1300 watt hair dryers running at once.
 

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On the flip side of this, the heater is supposed to take up a lot of battery power, while the seat heaters do not. What is the difference? Each of them works with a coil, inductive heater. The only difference seems like the blower motor.
Not quite. One of them only needs to heat a small surface (about butt and your back) and the other needs to heat the entire cabin.

So another tact would be to tint your windows so the AC wouldn't need to work so hard, but then the negligible weight of the film and extra cost may not be worth it, but you'll look cool in the process.

Plus if you buy a voltshelf, that eliminates several cubit feet that needs to be cooled by the AC. Plus, I've put drinks in the back under the voltshelf, and there is a dramatic difference in temps on 100+ degree days. You can actually drink what was stored in the trunk, you will burn yourself drinking something left in the cubholder.
 

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Discussion Starter #14
The seat heater and steering wheel heater are powered by the 12V system. They use 100 - 200 watts. The electric heat coil is powered by the 400V traction battery. The heater coils, there is more than 1, are immersed in coolant. The coolant circulates through the heating and cooling loop. The coils can draw up to 9kw, that is like (7) 1300 watt hair dryers running at once.
I appreciate that the seat/wheel heaters would use less, but that seems like overkill for the car heater system. I could envision an Eco setting that provides some warm air, without toasting the cabin. And whatever power is drawn from the 12v still has to be replenished from the main battery.
 

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I appreciate that the seat/wheel heaters would use less, but that seems like overkill for the car heater system. I could envision an Eco setting that provides some warm air, without toasting the cabin. And whatever power is drawn from the 12v still has to be replenished from the main battery.
The seat heater and steering wheel heater do use power but it does not even register on the DIC. When the Volt is turned on the 12V system is drawing 500w, at a minimum, all of the time. If you turn on the seat heaters and steering wheel heater the amount of power instantaneously being used does not change on the the display, it is below the threshold on the display. When you turn on the HVAC heat the amount power being used immediately jumps up to 4kw, 6kw or even 9kw.

The electric heat is best used to precondition the Volt while it is plugged in. 10 or 20 minutes of preconditioning can warm the cabin, the energy used can be replenished in the battery almost as quickly as it is being drawn provided you are charging at Level II. Once the coolant has been heated it does not take as much energy to maintain the coolant temperature. You can drive for 15 - 20 minutes, then cycle the electric heat on and off to maintain a warm cabin for the duration of the trip.

The Volt was designed to use gas some of the time. The Engine Heat Assist mode is more efficient at warming the cabin at temperatures below 35F than the electric heater. If you use the Engine Heat Assist to warm the cabin this uses very little gas and saves the battery capacity for EV driving.
 
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