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After driving 38k miles and through 2 winters I have come to the conclusion that 20 degrees Fahrenheit is the “big” difference in cold weather battery effect. While yes from 70 degree mornings to 20 degrees there is a drop in mileage. The biggest hit to me is below 20 degrees. Not counting he heater. While I use the heater sparingly I still do use it. But the mileage really drops off below 20. And 2 weeks ago when we had it -17, I still made my 130 mile round trip commute with 5-10’miles to spare.
I seem to take a bigger mileage hit below the 20 degree mark than I do above 20 degrees. I only see a little battery conditioning when pre heating also. Just my observations.
 

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I live in Georgia and waiting to see if my mileage will get back to 250-260 miles which I had when I got the Bolt in Sept '17 . Our winter has been cooler than normal and so far my miles after full charge are in 225 range . When I had that battery propulsion recall done last month my miles dropped to 205 after full charge but now they slowing climbing back up . I just need to wait for the 90 deg days to come .
 

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I have been noticing my average range drop considerably. This range went from 160 in 30 degree weather to 125 in 0 degree weather. That seems like a big drop off of the 238 I was getting in the summer. Is this reason for concern or do others see that low of an average range?
 

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I have been noticing my average range drop considerably. This range went from 160 in 30 degree weather to 125 in 0 degree weather. That seems like a big drop off of the 238 I was getting in the summer. Is this reason for concern or do others see that low of an average range?
This is pretty normal. In the optimal months (warm, but not hot) I was getting in excess of 5 mi/kWh, that is 300+ mi/battery. Click my badge below, if you like, to see the charging stats. About 160 mi at around freezing temps is exactly what I expect. I wouldn't dare to drive kEVin @ OoF - for that kind of weather God made ICE cars :)
 

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I have been noticing my average range drop considerably. This range went from 160 in 30 degree weather to 125 in 0 degree weather. That seems like a big drop off of the 238 I was getting in the summer. Is this reason for concern or do others see that low of an average range?
Seems about right.... don't sweat it, you'll be back up to 250mi plus soon enough.
 

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This is pretty normal. In the optimal months (warm, but not hot) I was getting in excess of 5 mi/kWh, that is 300+ mi/battery. Click my badge below, if you like, to see the charging stats. About 160 mi at around freezing temps is exactly what I expect. I wouldn't dare to drive kEVin @ OoF - for that kind of weather God made ICE cars :)
Next Wednesday it supposed to be a high of -8 for the day. I can't wait to see what the range is on that day.
 

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I have been noticing my average range drop considerably. This range went from 160 in 30 degree weather to 125 in 0 degree weather. That seems like a big drop off of the 238 I was getting in the summer. Is this reason for concern or do others see that low of an average range?
What kind of driving do you do? Mostly short trips? (The shorter your trips, the more you'll be impacted by the energy needed to warm the car and the more pessimistic the car's range estimates will be.)
 

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Next Wednesday it supposed to be a high of -8 for the day. I can't wait to see what the range is on that day.
If there is a way, you may want to record the details of your trip: average speed, terrain, weather/road condition etc., because those are also pretty big factors. The brethren (and sistren) here on forum would surely be grateful if you shared L)
 

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What kind of driving do you do? Mostly short trips? (The shorter your trips, the more you'll be impacted by the energy needed to warm the car and the more pessimistic the car's range estimates will be.)
I tend to drive anywhere from 30 to 100 miles on a given day (round trip). That is mostly highway miles. today it was -10 on my way there and I warmed the car up in the garage while plugged in to help extend my range. It said I was starting with 135 miles and I drove 48 miles to work. When I got there it said I had around 98 miles of range. Warming the car ahead of time definitely helped but I will see what it looks like when I have to leave for home today.
 

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In areas that commonly reach those temperatures, isn't it common for many parking lots to have block heaters (i.e., 120 V outlets at parking spaces)? It's not so much to charge the vehicle as it is to keep the battery warm while parked during the day.
 

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In areas that commonly reach those temperatures, isn't it common for many parking lots to have block heaters (i.e., 120 V outlets at parking spaces)? It's not so much to charge the vehicle as it is to keep the battery warm while parked during the day.
I haven't seen the block heater plugs in front of parking spots anywhere in MN but they definitely have them up in Winnipeg, CA (they need them there - coldest place I've ever been in my life in January). I'd be curious if there are other cold regions of the US that have these as a standard. I'm lobbying our local airport to put in more 120V outlets in airport parking. L2 is over-saturated (only a dozen or so stalls) and really for airport multi-day parking, L2 is not necessary - just want some energy to keep the battery warm and precondition on return without reducing driving range.
 

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If there is a way, you may want to record the details of your trip: average speed, terrain, weather/road condition etc., because those are also pretty big factors. The brethren (and sistren) here on forum would surely be grateful if you shared L)
You didn't ask me specifically, but I've started taking more cold weather data that may interest you and others. Some plots of initial data in the link below.

https://photos.app.goo.gl/WFPMZRPoW58bNyvHA

This is my commute route that is 14.1 mls each way. Most of the distance is county roads at 60 mph (divide the trans rpm by ~ 95 and you get speed in mph) before getting into town driving. The roads are clear with now rain/snow, except for the short distance of gravel road/driveway into my neighborhood and garage which has some snow, that likely won't melt anytime soon (projecting lows in the -20's and "highs" in the negative single digits for most of next week).

This morning was -14F air temp, but my attached garage was at 36F. I've recently changed my charging cycle so it finishes the charge shortly before I leave for work. This way the battery conditioning added at the end of the charge cycle has the battery at a good and warm temp. In the summer I had things set to charge right away as my solar panels were still making some power in the afternoons when I got home, but in the winter this isn't a good strategy. The battery would loose heat after being charged and conditioned in the afternoon/evening and then often need heating again before the morning commute.

So on this bone chilling cold morning the battery started at a nice and toasty 53.6F, and lost heat as I was driving to work. But it didn't use any battery conditioning power, as shown in the 2nd graph. I needed to run the window defroster at a high level to see. Took 6.2 kWh for the 14.1 mile trip. It would've been more if the battery wasn't warm to start.

1st graph is from yesterday afternoon. It wasn't nearly as cold, but the battery lose a lot of heat during the day and started the return trip at 26.6F. Battery heating came on right away at a ~2.2kW level for the entire trip, and you can see the battery temp slowly rising up to 35.6F when I got home. There was also a head wind. It took over 7 kWh for the return trip.

I'll add a graph this afternoon for the return trip. Curious to see how much heat the battery looses today and what the total kWh power usage is for todays round trip...
 

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I'm lobbying our local airport to put in more 120V outlets in airport parking.
We share the same airport. And the same experiences. I agree a plethora of 110V outlets is a much better solution for the airport.
Who have you approached? I would gladly 2nd your suggestions to the same authorities.
 

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...
I'll add a graph this afternoon for the return trip. Curious to see how much heat the battery looses today and what the total kWh power usage is for todays round trip...

Added graph and image of cars total consumption info into the the link above.


Battery was down to 24.8F for the return trip in +5F afternoon temps and the battery heater ran the whole time like yesterday afternoon. Total power used for the ~28.2 mile commute was 13.3 kWh, or ~2.12 ml/kwh. Will be interesting to see how low the efficiency gets next week when things are supposed to be even colder.



Extra info ... No pre-conditioning used today, which would make driving more comfortable but also cause more kWh to be consumed. 42psi tire pressure registered by the car this afternoon is within a couple psi of where I try to keep things in the summer, and I'm using the same wheels/tires as used in summer, where I usually see ~4.6-5 ml/kWh for this same driving scenario.
 

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Added graph and image of cars total consumption info into the the link above.


Battery was down to 24.8F for the return trip in +5F afternoon temps and the battery heater ran the whole time like yesterday afternoon. Total power used for the ~28.2 mile commute was 13.3 kWh, or ~2.12 ml/kwh. Will be interesting to see how low the efficiency gets next week when things are supposed to be even colder.
...

Added another chart and pic of total consumption for the round trip today. 0F in the morning with a battery that started at a toasty 57F after the departure charge and ~30 mins of post charge conditioning in my attached garage, and cooled off to 15.8F after sitting outside for 7.5 hrs (I left work a little early today....) with 0F air temps in the afternoon.



Averaged 2.058 ml/kWh today.



Overnight lows around -30F air temp (-55F wind chills) and predicted highs tomorrow of -18F air temp. Similar for the following day. But almost everything is getting canceled and our large corporation has taken the unusual step of telling people they don't "have to come to work IF they don't feel safe for the next 2 days ... but the doors will be open if you want to come in." So I may just feel unsafe and stay home and not log the Bolt getting <2ml/kWh....
 

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I've sent a note to ParkMSP:
http://mspairport.com/contact-us

I haven't heard back yet but just sent it yesterday.
Got a reply - they will be adding 50 L2 EVSEs in the new Silver ramp opening in April 2020. They also said they would take my recommendation of adding some 120V plugs in a designated area for a trickle charge using the owners own cable (and hopefully a little battery heating)...
 

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... So I may just feel unsafe and stay home and not log the Bolt getting <2ml/kWh....

Added more data for today on the link.


Went to work today despite the -30F air temp. We're starting to warm up, however, and the afternoon temp was up to a balmy -3F for the return trip. The bolt consumed 14.4kWh for the 28.3 mile round trip for a whopping low 1.965 ml/kWh consumption figure. And this doesn't include all the extra power used to condition the battery (I finish charging ~30 minutes before departure which is about enough to get the battery conditioned from the normal charging procedure to close to 60F as seen in the plots for the morning drive). The morning drives with a warm battery are more efficient than the return trips with a battery that has cooled off while parked at work.



I'll be compiling the daily charger total power consumption for the car as well (it keeps track of total power pushed into the car for charging and all the other things like heating the battery), so this will give a better "kWh for miles driven" as opposed to what is reported by the car.



Note: I have not used pre-conditioning of the car for these tests as that would just use MORE total power.
 

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Just a couple of F's and F's, in case someone is compiling these:

Distance, roundtrip: 78.1 mi
Average Speed: 46 mph
Weather: 10F to 20F (fluctuations mostly due to the road's elevation profile), dry, low to no wind
Juice Efficiency: 2.85 mi/kWh
Cab Heating: HVAC doodad at 68F + seats.

On this route I get 5.1 mi/kWh in optimal weather. The readings from yesterday represent 44% lower juice efficiency vs. optimal/peak and 34% vs. lifetime average. The extrapolated range would be 171 mi. With this juice efficiency the Bolt, in order to stay a 200+ mi EV, would need a 70 kWh battery, which his not an insurmountable challenge.
 
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