This weekend I had about a 170 mile drive. When I left the house, my range said I should arrive with about 67 miles to spare. Temp was in the 30's without much wind and there were scattered snow flurries and intermittent wet roads. As I drove the gap between range and mileage left kept narrowing. When I was about 12 miles away it stopped showing a range calculation. I did make it, but definitely had some range anxiety and the conditions really reduced the expected range. (Note: Trip was made with 12 passenger van with ICE engine. It's not just electric that suffers from cold and wet conditions.)
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Range reduction in cold
- Thread starter cdeleo
- Start date
For the data geeks, or those trying to extract the last mile of range, TeslaFi can schedule charge limit adjustments, start/stop charging, and start/stop climate. I know there are other apps that can do the same, but this is the one I've been using. A split charge should be easy to set up. The morning charge would the always be starting and ending at the same charge levels and should have a consistent time duration.
That 55% is misleading. Your note suggests that all of that range reduction is due to cold. That is not true.
What is your range loss on a 75F degree day with the same driving characteristics? I bet that would be around 20% given that you have driven 75 mph for half the distance.
So that leaves a 35% hit for cold weather, which is in the ball park of what you would expect.
Cold weather is a triple whammy:
- battery shows less than what it really has (if it is cold soaked overnight), but you get thaat back when battery warms
- energy spent on heating cabin (and sometimes for the pack too when it is close to 0F).
- Increased air resistance due to denser air when temps are cold.
I don't know what the range loss is at 75F as I have not driven the car in that kind of weather lol. I'll let you know next year. Again my post was more for a direct comparison to what I had with my ICE vehicle. I got really good at knowing the range of my ICE car. So much so that I could bring it right down to what most people would think would be crazy.
You do make a really good point that my title is misleading I should have stated in reference to EPA ratings. As far as speed goes I don't know what EPA uses to reference "highway" and city. is the 310 miles of range estimated for 55mph driving? an avg of between 55 and 75 or even 80mph, which some states have highway speed limits?
My goal of the post was just to provide a real world number with some description of my commute.
I'll admit I don't spend much time driving 12 passenger vans but I think you would be hard pressed to find an ICE car that the mpg dropped by 35% in the cold. I know from my experience that my old ICE car would drop about 1.5 maybe 2 MPG in the winter. from a summer average of about 24mpg at around 12000 miles of summer driving to about 22mpg in the winter also about 12000 miles of driving. at 35% that would be a drop of around 8mpg so that would have been more like 16mpg in the winter and that's using 35%.
I just think it's important to post some data about this to try and help people who are trying to figure out if SR MR LR or god forbid less then that range will work for them. Just relying on EPA ranges is not enough. I'll be honest I didn't even think of the charging to only 80% for good battery health.
Just another data point for my way home tonight
The weather actually ws about the same wind was lower around 3mph but at a head wind this time. temps where about the same as in the am around 30F when I left and around 24F when I got home. This time range lost was 48 miles for the 33 mile trip. The battery and car where much warmer as it was in the underground garage at work. Which is around 55F. Also I noticed that I had much more regen when I left it was right under the D for drive on the display. In the am I had basically none. I kept the same driving style as the am used AutoPilot for about 85% of the drive and had about 50% at 77mph and the other at 60mph. traffic was about the same with no issues. temp and seat settings where the same. obviously I had headlights on this time so that was a difference.
Also just for reference I used to drive an awd lexus GS 350 which again with the same driving style got about 24mpg in the summer and 22mpg in the winter. It used to get much better than this but with 150k miles on it and being a 2010 car it started to reduce the mpg. All and all though I felt that it was a pretty good comparison car to the Model 3 LR AWD. obviously not perfect but in the same pricerange when new, about the same weight. I would say about the same performance but I know that would get me in trouble lol because it did 0-60 in 5.7 which is a lot less than the tesla I have now doing it in 4.5 But I don't know if the Tesla can do the 4.5 at the end of my day when the battery is closer to the 50% mark. Guess maybe that should be another forum post. 0-60 times with different state of charge.
The weather actually ws about the same wind was lower around 3mph but at a head wind this time. temps where about the same as in the am around 30F when I left and around 24F when I got home. This time range lost was 48 miles for the 33 mile trip. The battery and car where much warmer as it was in the underground garage at work. Which is around 55F. Also I noticed that I had much more regen when I left it was right under the D for drive on the display. In the am I had basically none. I kept the same driving style as the am used AutoPilot for about 85% of the drive and had about 50% at 77mph and the other at 60mph. traffic was about the same with no issues. temp and seat settings where the same. obviously I had headlights on this time so that was a difference.
Also just for reference I used to drive an awd lexus GS 350 which again with the same driving style got about 24mpg in the summer and 22mpg in the winter. It used to get much better than this but with 150k miles on it and being a 2010 car it started to reduce the mpg. All and all though I felt that it was a pretty good comparison car to the Model 3 LR AWD. obviously not perfect but in the same pricerange when new, about the same weight. I would say about the same performance but I know that would get me in trouble lol because it did 0-60 in 5.7 which is a lot less than the tesla I have now doing it in 4.5 But I don't know if the Tesla can do the 4.5 at the end of my day when the battery is closer to the 50% mark. Guess maybe that should be another forum post. 0-60 times with different state of charge.
2012MS85
Member
I have wonderful news for @cdeleo and all others worrying about range loss due to cold weather
You didn't lose 55% of your expected range, as I think you flipped the numerator and denominator when doing your calculation. To compute what your "real world" efficiency (as compared to expected range your Tesla is showing when you leave home), please divide how far you're driving (33 miles round-trip to work) by the miles used (starting range minus ending range). If you do that on your two examples, here are your actual "cold weather" results (which are exactly what most of us driving EVs in cold weather achieve):33 / 51 = 65% efficient...ergo, a 35% "loss" due to cold/speed
33 / 48 = 69% efficient...ergo, a 31% "loss" due to cold/speed
Voila! You just "found" some kWh of energy that were never really "lost"
I have a 2,005-mile Supercharging trek from Seattle to the Mississippi River this weekend in my newly purchased 2012 P85, so I'm double-checking every calculation to ensure the cold weather (forecast down to 0 F in Butte, Montana, which is also the state with no actual speed limit
) doesn't prevent me from reaching each of my 19 Superchargers along my journey! Based on my previous experience of sub-zero driving in the Midwest with my previous S85, the worst-case scenario (heat blasting, pedal to the medal, and bone-chilling cold outside) I experienced was a 50% efficiency (of the range showing on my TESLA's dash).
ljbad4life
Member
My experience in the cold so far is stop and go traffic combined with heater usage throws my consumption up by about 25%. My suggestion is precondition while plugged in then and use the seat heaters liberally. When i keep the heat to 67F and the seat heater set to high. I'm comfortable and the range hit is equivalent to if I didn't have the wheel covers on. My avg so far is 209wh/mi compare to 230wh/mi over the last couple of cold days.
How can I get my wh/mi for my avg. So far? I only see trip and 5, 15 and 30 min.
Swipe right over the bottom left of the screen (below the car display) and your trip calculations will show up. There will be Trip A, Trip B, current drive and since last charge.
If you swipe left, it will show your tire pressures.
2012MS85
Member
That's why I'm here as your numbers geek
To help everyone make this calculation easy to remember so no one runs out of juice on their commute home after a long, hard day of work The key is to remember that the bottom number (denominator) should always be the miles your TESLA said you'd get (i.e., your expected range...which is the 51 miles). So what you used will be your efficiency (i.e., 33 miles traveled, divided by 51 miles your car said you'd get under ideal conditions...which means nice Spring or Fall weather with no heat or A/C). In that scenario, you're at 33/51, or 65% efficient...which for simple memory is 2/3 of "IDEAL". So if your Tesla says you're charged to 150 miles, you can feel pretty confident you're good to drive 100 miles before you might need a flatbed tow to the nearest Supercharger And if you want to look at it in reverse, the 18 miles "lost" can also be divided by 51, which shows you've "lost" 35% of your ideal range. Whichever way your brain most easily computes numbers
"33 / 51 = 65% efficient...ergo, a 35% "loss" due to cold/speed"33
I guess the other way to look at this would be, how many 33 miles trips could you do.
For 100% efficiency, it should be 310/33 = 9.4 trips
What you're actually getting is 310/51 = 6.1 trips
So you 'lost' 9.4-6.1=3.3 trips. At 33 miles, that is 108.9 miles. Or 108/310 = 34% loss.
Also I wanted to add that the loss due to cabin heating works against us in the winter compared to an ICE. Since the heat is a byproduct of its inefficiency, cabin heating is a useful by-product. But in the summer the opposite is true. The ICE car will continue to generate this heat but it's unwanted, decreases efficiency, and requires complex cooling systems.
I guess the other way to look at this would be, how many 33 miles trips could you do.
For 100% efficiency, it should be 310/33 = 9.4 trips
What you're actually getting is 310/51 = 6.1 trips
So you 'lost' 9.4-6.1=3.3 trips. At 33 miles, that is 108.9 miles. Or 108/310 = 34% loss.
Also I wanted to add that the loss due to cabin heating works against us in the winter compared to an ICE. Since the heat is a byproduct of its inefficiency, cabin heating is a useful by-product. But in the summer the opposite is true. The ICE car will continue to generate this heat but it's unwanted, decreases efficiency, and requires complex cooling systems.
This morning at 42F my efficiency was 270 Wh/mile, whereas in summer I was averaging at 225 wh/mile.
So that is an increase of 35 Wh/mile or 35/225 = 15% increase in consumption. Which means instead of 310 miles at full charge I will get 263 miles (a 15% range reduction). I can live with that.
Now in much lower temps in the teens, I am sure there will another 15% loss, or a full range of 200+ miles.
So that is an increase of 35 Wh/mile or 35/225 = 15% increase in consumption. Which means instead of 310 miles at full charge I will get 263 miles (a 15% range reduction). I can live with that.
Now in much lower temps in the teens, I am sure there will another 15% loss, or a full range of 200+ miles.
WATT TF
Member
The efficiency and consumption calculations are definitely appreciated. I'm an engineer and would love to continue talking numbers, but I think it is safe to say battery performance is not ideal in cold climates - even concerning at times.
My energy loss due to cold weather is similar to what everyone describes above.
I drive 60 miles roundtrip to work, about 40 miles spent going 70-75mph and the remaining 20 miles in stop and go traffic. Each trip is about 1 hour. Based on this schedule I was expecting to charge to 80-90% once every 3-4 days at a local (typically empty) supercharger. When at work my car is parked outdoors (20°-30°) and indoors when at home (40°-45°). I left for work yesterday morning with 89% charge and did run an errand requiring 10 additional miles - 70 miles total yesterday.
I got to work this morning and my range was 120 miles (30 mile drive), and after sitting in the parking lot for 5 hours it is at 99 miles (now at 98!). I am unfortunately sitting at work wondering if 99 miles is enough for me to make my 30 miles commute home over some of the flattest terrain in our country. Also need to account for loss of another 3-5 miles before leaving.
Calculating energy loss is not very helpful for someone that commutes 60 miles daily and potentially needs to charge everyday, or drive home every other day with an extremely low charge. I definitely did not plan on charging everyday when buying a car with 310 mile range, even after accounting for a minor reduction in range during winter.
My energy loss due to cold weather is similar to what everyone describes above.
I drive 60 miles roundtrip to work, about 40 miles spent going 70-75mph and the remaining 20 miles in stop and go traffic. Each trip is about 1 hour. Based on this schedule I was expecting to charge to 80-90% once every 3-4 days at a local (typically empty) supercharger. When at work my car is parked outdoors (20°-30°) and indoors when at home (40°-45°). I left for work yesterday morning with 89% charge and did run an errand requiring 10 additional miles - 70 miles total yesterday.
I got to work this morning and my range was 120 miles (30 mile drive), and after sitting in the parking lot for 5 hours it is at 99 miles (now at 98!). I am unfortunately sitting at work wondering if 99 miles is enough for me to make my 30 miles commute home over some of the flattest terrain in our country. Also need to account for loss of another 3-5 miles before leaving.
Calculating energy loss is not very helpful for someone that commutes 60 miles daily and potentially needs to charge everyday, or drive home every other day with an extremely low charge. I definitely did not plan on charging everyday when buying a car with 310 mile range, even after accounting for a minor reduction in range during winter.
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Kermee
It's Not Easy Being Green
It's been in the mid to upper 20F's where I live the past few days. My daily commute is about 100 miles, about 3 hours worth of driving, so I decided to do some testing using the trip meters.
1. Drive normally with HVAC at 72F (A/C on, Recirculating Air) with heated seats. Energy usage average was around 350 Wh/mi.
2. Drive normally with HVAC at 60F (A/C off, Outside Air), no heated seats. Energy usage average was around 230 Wh/mi.
3. Drive normally with HVAC completely off, no heated seats. Energy usage average was around 210 Wh/mi.
For #3, I did have to crack open the windows every once in a while to help reduce foggy windows (Outdoor humidity is non-existent so opening the windows sucked out all the moisture for a short while). I was also tripled layered, wearing gloves, so I didn't freeze and the Tesla mobile app on my phone showed the interior temperature to be around low 40F's after driving a bit, which was about 20F above outside ambient. (Maybe my own body heat and other electronics warming the cabin naturally along with sunshine on a black vehicle).
When I first received my Model 3 in August, I was averaging about 215 Wh/mi when the ambient was about 70F. So to me, it's obvious that the major cause of range reduction is my Model 3 trying to keep the cabin temperature close to 50F above ambient, for the entire duration of my 3 hour commute. I don't think there's much loss of "efficiency" due to the cold, in the technical sense. However, obviously at lower temperatures, LiON batteries suffer in the sense that the available energy available to be used when the pack is "cold-soaked" is reduced. You gain that energy back as the pack warms up.
Also, you don't see this type of range reduction in ICE vehicles in similar conditions are due to the fact you're using waste heat (it in itself, the literal definition of efficiency loss) to heat the cabin.
So moral of the story is, plan accordingly with the knowledge nuggets peppered in this thread.
EDIT: P.S. This is how you really "mess" with your energy graph when you have the HVAC to "Hi" and drive around hills a bit...
1. Drive normally with HVAC at 72F (A/C on, Recirculating Air) with heated seats. Energy usage average was around 350 Wh/mi.
2. Drive normally with HVAC at 60F (A/C off, Outside Air), no heated seats. Energy usage average was around 230 Wh/mi.
3. Drive normally with HVAC completely off, no heated seats. Energy usage average was around 210 Wh/mi.
For #3, I did have to crack open the windows every once in a while to help reduce foggy windows (Outdoor humidity is non-existent so opening the windows sucked out all the moisture for a short while). I was also tripled layered, wearing gloves, so I didn't freeze and the Tesla mobile app on my phone showed the interior temperature to be around low 40F's after driving a bit, which was about 20F above outside ambient. (Maybe my own body heat and other electronics warming the cabin naturally along with sunshine on a black vehicle).
When I first received my Model 3 in August, I was averaging about 215 Wh/mi when the ambient was about 70F. So to me, it's obvious that the major cause of range reduction is my Model 3 trying to keep the cabin temperature close to 50F above ambient, for the entire duration of my 3 hour commute. I don't think there's much loss of "efficiency" due to the cold, in the technical sense. However, obviously at lower temperatures, LiON batteries suffer in the sense that the available energy available to be used when the pack is "cold-soaked" is reduced. You gain that energy back as the pack warms up.
Also, you don't see this type of range reduction in ICE vehicles in similar conditions are due to the fact you're using waste heat (it in itself, the literal definition of efficiency loss) to heat the cabin.
So moral of the story is, plan accordingly with the knowledge nuggets peppered in this thread.
EDIT: P.S. This is how you really "mess" with your energy graph when you have the HVAC to "Hi" and drive around hills a bit...
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dgpcolorado
high altitude member
While using cabin heat is the greatest contributor to reduced range in cold weather, there are other factors at play:
•Cold air has greater density and increases aerodynamic drag.
•Cold tires and gear lube cause increased rolling resistance.
•Snowy or slushy roads can also lead to greatly increased rolling resistance.
•Regen braking is reduced for cold batteries; this can be significant for those descending steep hills.
•A cold battery will be heated to perform better — this energy comes from the battery until the drive system warms up.
So, even if you don't use climate control at all, mileage efficiency and range will decline in cold weather.
While you don't see the same losses in ICE cars, due to cabin heat being "free," gas mileage does decline in cold weather. It just tends not to be noticed much unless one keeps meticulous logs, as I did for decades. Few people care about the range of an ICE car when there are gas stations almost everywhere.
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WATT TF
Member
Very helpful experiment!
I typically drive with HVAC on auto at 66°. My ICE car did not have auto climate and the only circumstance I had A/C on with the heat was with foggy windows. I knew the A/C harmed efficiency and very rarely used it during winter months and turned it off when condensation disappeared. On my M3 I am obviously unable to use the auto climate control with A/C permanently deselected as that is not truely automatic.
Your experiment is validating my assumption that it's possible to improve range by manually controlling climate to leave AC off.
I think the reason most of us experience a loss of energy due to cold weather is from the car preventing the battery from reaching a "cold soaked" state. The amount of energy "lost" with the car parked was probably consumed to keep the battery from freezing. I have a hard time believing otherwise considering my car has already lost 12-15 miles while parked outside today and it's only lunch time.
For comparison purposes here is a graph of my drive to work where I consumed an average of 324 Wh/mi - in line with situation #1.
