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Attached is a screen shot from my solar system’s power meter. When I installed the EVSE, I added a current tap in the panel box to totalize the car usage. Please note that I haven’t setup the current measurement properly so the power draw for the car charger is 1/2 what it really is. When I got home and plugged it in, it charged right away and since it was cold last night, it did two battery heat cycles. Also note the charge profile. It started drawing a lot of power and slowly tapered off to about 95% of the original draw, then dropped significantly and tapered rapidly.
 

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That seems pretty typical compared to what others have posted regarding battery "conditioning" in cold temps.
 

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I'd like to know how much conditioning power the Bolt uses when it's unplugged.
It will vary depending on how cold and how much SOC you have. Others on the forum have posted the exact numbers but I vaguely recall 30% SOC is the cutoff when the system will stop using the traction battery energy to condition itself. I think for a -13F to 2F temp swing in one day, someone on the forums loss 8 kWh of energy.
 

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I sure wish there was some way to shut off that battery warming feature for long term parking. For example, I'm flying out for a week and the car will be at airport. It's not right for me to leave my car plugged in the whole time and prevent others from using the EVSE in airport parking. There's a "car wash" mode... what about a long term parking mode?
 

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I sure wish there was some way to shut off that battery warming feature for long term parking. For example, I'm flying out for a week and the car will be at airport. It's not right for me to leave my car plugged in the whole time and prevent others from using the EVSE in airport parking. There's a "car wash" mode... what about a long term parking mode?
The car should be fine being left unplugged at the airport for a week. The amount of power used for Battery conditioning isn’t that much. It doesn’t run nearly as often when unplugged as opposed to when it is plugged in. One person reported that SOC dropped from 67% to 63%, which implies that the car used about 2.5 kWh to keep the battery happy while it sat.
 

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Also note the charge profile. It started drawing a lot of power and slowly tapered off to about 95% of the original draw, then dropped significantly and tapered rapidly.
We have seen quite a few of these charts now. The taper may be explained right here.

The first, an immersion heater, can be deployed in coolant-based cooling systems. In this system, a heater heats the coolant to achieve the opposite of its normal cooling effect. “These are PTC, which stands for Positive Temperature Coefficient,” Kelly describes. “What that means is that as the temperature rises, the resistance of the heater will rise. And with constant voltage, that means your wattage starts to drop. The automotive market likes it because it’s a self-regulating effect. It’s got a built-in safety feature without having to complicate their controls.”

https://chargedevs.com/features/the-goldilocks-zone-caliente-explains-that-battery-pack-heating-is-just-as-important-as-cooling/
 

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Battery Conditioning for 439 Hours

My Bolt was left parked in garage and plugged-in for 18 consecutive days. Graph below shows EVSE usage from the time battery conditioning commenced on December 31st until I unplugged the vehicle on January 18th.

Total EVSE usage was 105.95* kWh’s for the 439 hours or 18.3 days. Ambient temp in garage averaged -6.1°C (21°F). Works out to an average usage per 24-hr day of 5.8 kWh’s.
* Chargepoint Home 25, 240v/32A. note this is EVSE usage not exactly Bolt usage and includes whatever parasitic draws the idle Bolt may have.

According to other posts presumably this usage kept the battery temperature in a range around 40°F. Just eyeballing the chart suggests usage & ambient temp are inversely related, no surprise there.

Note also that usage peaked around 0.5 kW’s during the coldest days. Usage rates support the theory that Canadian Bolts are programmed to battery-condition differently than USA Bolts.

Unplugged usage would have been less due to: 1.) from other posts it’s indicated that Bolt uses less kWh’s on its own (tbd) when unplugged, and 2.) from other posts it’s indicated that Bolt cuts down on usage once SOC gets down to 30% and below. (tbd)
 

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Sorry ahead of time if I'm less sophisticated about all of this. I got my Bolt end of November and live near Boston. I was told to leave it plugged in if possible when it's below 32 degrees. It was bitter cold around here end of December, and I was a bit surprised to see an electric bill double the normal, from around $100 to $250. Some of that could be due to other factors, but I'm wondering what others have been experiencing. I'm guessing this bill covers around 900 miles driving. If it's relevant, I've just been using the 110 volt charger, except on one trip where I charged with a 220 level 2 ( not on my electric bill). Thanks in advance,
Andy
 

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I'm guessing this bill covers around 900 miles driving.
Andy
If it was me who did the 900 miles in an electricity billing month. At the present time I’m averaging around a poor 20 kWh/100 km (3.1 miles per kWh).

So 900 miles would have used around 290 kWh’s. At present my incremental hydro cost is 10.453¢ per kWh. So for 290 kWh that extends out to $30. Add on to that the plugged-in parked battery conditioning usage of perhaps 6 kwh per day when Bolt is unused for a time.

900 miles would have cost about $158 for gasoline for my wife’s Buick Encore. (gas is very expensive here - - about the equivalent of $4.30 Cdn per US gallon).

Bottom line: don’t worry about Bolt’s hydro usage. In this case it’s a minor component of the increased hydro bill. If your EVSE doesn't measure Bolt usage perhaps someone can suggest an add-on to do that.
 

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The 'standard' (included with car) 120V EVSE is not as efficient as one at 240V - that's just physics.

Also, several (many?) posters on this forum plug the 'standard' EVSE into a 240V socket (using a custom converter/pigtail cord), getting about 2.8 kW of charging - much better than the 120V charging.

(Of course, if you don't have a 240V socket available, that doesn't help you.)
 

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In the 1 month that I’ve owned my Bolt, it’s been very cold in MI, and my average over 1000 miles is just over 2.5 mi per kwh. This includes about 25% for climate and battery conditioning. With recent warmer temps I have seen the 5 mile segment bars occasionally show more than 4 mi per kwh, so I know the car is capable of average efficiency once the temps warm up. Hurry up spring!
 

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We had six weeks of real winter temperatures here, then a 69F day. The mi/kWh went from the 2.5-3.5 mi/kWh we were seeing back to 4.4 mi/kWh. Can't wait for spring!
 

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I'd like to know how much conditioning power the Bolt uses when it's unplugged.
That continues to be the million dollar question.

It's now been 45 hours since I parked my Bolt unplugged in the garage. At 3 o'clock Thursday when I parked it, the Energy Detail screen said 0% battery cond usage and 3.4 kwh's used since last full charge.

I just now went out and fired it up & it now says battery usage 1% but still the same 3.4 kwh's used. Don't know what I'm doing wrong if anything. Thursday nite it was -4C (25F) and yesterday and today around 0C (32F).

Could be that unplugged, the car is programmed to a lower temp threshold for batt conditioning. Versus keeping battery around 40F plugged in.
 

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This post (on another forum) by user "MikeDabrowski2017" : http://www.mychevybolt.com/forum/viewtopic.php?p=29292#p29292

We just got a break in some pretty cold weather here in new England.

From my observations during the coldest periods, the battery temperature seems to be maintained at a similar energy regardless of being plugged in or not.

I don't drive the car every day and I leave the car plugged in to my level 2 EVSE JuiceBox which logs all charging or conditioning in a graph. After watching the kWh drawn to condition the pack for several days plugged in, I unplugged the car for a similar period of time and based on the percentage of charge used for conditioning recorded by the car, i saw just about the same kwh used. Looks like the conditioning cycles run at about 6 hours off 30 minutes to over an hour on or .7kw to 1.5 kw per cycle. Thermal camera looking at the fluid hoses saw 70- 80 degrees on the exterior of the hoses while the conditioning was active.
 
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