Summer vs Winter KWh use

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Hofty

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Folks,

Getting 15-18Kwh in summer.
Getting 24-28Kwh in winter.
Anyone else getting same results?

Notes: Did add steel rims and winter tires including a roof box so maybe that's also the reason. Ambient outside temperature is 2-7degrees celcius
 
Winter tires have only about 5-10% effect on consumption, roof box definitely makes things much worse at highway speeds, freezing temperature and precipitation are also big factors. Your numbers seem pretty normal otherwise.

Sent from my SM-G955W using Inside EVs mobile app
 
I assume this is your consumption and not charge rate and it is Kwh/ 100km. This would equate to
4.14 -3.45 miles per Kwh in summer (USA Kona EV report of consumption)
2.6 to 2.2 miles per Kwh in winter.
Only difference is you divide 62.15 by your consumption.
This is a close for us in Summer but a bit low for winter. Our winter is not as cold as yours. This looks like it's in normal usage range.
 
So yes the KWh measurement are for Canada hence KWh/100km. It is interesting how drastic the change was with the winter tires/rims and box added.
 
Anything at all on the roof can make a big difference. The box is more aero than a ladder or a bicycle, however. I will give you that[emoji1].

When we first bought out house in Delaware. I went down in my ICE car with two ladders on the roof. Made a horrible noise the whole way down.
 
How cold does it need to be to make a noticeable difference? Thus far in cool but temperate San Francisco (recent days have had highs around 58-62 and lows in the mid-40s), I've seen no difference at all.
 
Bruce M. said:
How cold does it need to be to make a noticeable difference? Thus far in cool but temperate San Francisco (recent days have had highs around 58-62 and lows in the mid-40s), I've seen no difference at all.
Click to expand...
Your car's climate control is using less (if any A/C) now and not cold enough to use the heater much. But once you get below 40F, you'll notice a diff. Also, colder air is more dense, hence more drag. That however, is more linear and in San Fran you never really get very hot there, or cold, so that also has less effect where you live.
 
R P said:
Also, colder air is more dense, hence more drag.
Click to expand...

While there is an effect from that, it isn't a strong one. I looked up the density of air at various temperatures:

1.225 kg / m3, at 15 degrees C and at sea level.
1.292 kg / m3, at 0 degrees C and at sea level.
1.367 kg / m3, at -15 degrees C and at sea level.

I have seen various things suggested as to the cause for lower economy in the winter.
  1. Increased rolling resistance from stiffer tires.
  2. Increased drag from more dense air.
  3. Increased internal resistance in the battery when it is colder resulting in lower efficiency.
  4. Use of heater to keep the cabin comfortable.
My sense (without a lot of evidence of my own) is that it is #3 and #4 that are the big ones. This link suggests that just preconditioning the battery can buy you back a good chunk of the range you lose in the winter:

https://www.greencarreports.com/new...ic-cars-in-winter-tips-from-experienced-owner

That being said, if one were on a longer trip of several hours, the battery pack ought to warm up just from scavenged heat, and the #3 penalty would gradually go away. I haven't been able to do exhaustive tests to try out this theory however. I would sort of want to wait for a really cold day, and then map pack temperature as a function of time once I got on the highway. It just hasn't gotten cold enough here yet to make it worth my while to attempt such a test. And we have a heated garage which complicates matters (I suppose I could just leave the car outside overnight).
 
Well, like I said, it depends a lot where you live. In a place like Manitoba (APU) 80F in summer and -30F in winter are not uncommon. That equates to a diff of 8000 ft in density altitude, and 25% in drag effect. I am a pilot, and for us it is well known that if we fly at 8000 ft, the air is 75% as dense as at sea level (less drag). Here is a density altitude calculator if you want to play around with it. 59F is standard temp and 29.92 is standard air pressure.
http://www.pilotfriend.com/pilot_resources/density.htm

Also your car's rolling resistance incl internal shafts/gears/bearings are also much higher at -30F. Lots working against you in severe cold.
 
ericy said:
While there is an effect from that, it isn't a strong one. I looked up the density of air at various temperatures:

1.225 kg / m3, at 15 degrees C and at sea level.
1.292 kg / m3, at 0 degrees C and at sea level.
1.367 kg / m3, at -15 degrees C and at sea level.

I have seen various things suggested as to the cause for lower economy in the winter.
  1. Increased rolling resistance from stiffer tires.
  2. Increased drag from more dense air.
  3. Increased internal resistance in the battery when it is colder resulting in lower efficiency.
  4. Use of heater to keep the cabin comfortable.
My sense (without a lot of evidence of my own) is that it is #3 and #4 that are the big ones. This link suggests that just preconditioning the battery can buy you back a good chunk of the range you lose in the winter:

https://www.greencarreports.com/new...ic-cars-in-winter-tips-from-experienced-owner

That being said, if one were on a longer trip of several hours, the battery pack ought to warm up just from scavenged heat, and the #3 penalty would gradually go away. I haven't been able to do exhaustive tests to try out this theory however. I would sort of want to wait for a really cold day, and then map pack temperature as a function of time once I got on the highway. It just hasn't gotten cold enough here yet to make it worth my while to attempt such a test. And we have a heated garage which complicates matters (I suppose I could just leave the car outside overnight).
Click to expand...
That's definitely hard to test. Since you would have to rule out things like road conditions and elevation changes (going uphill/downhill). But definitely interesting to try.
 
R P said:
Well, like I said, it depends a lot where you live. In a place like Manitoba (APU) 80F in summer and -30F in winter are not uncommon.
Click to expand...

Yes, for those extremes, the difference in air density gets to be a lot more significant. I don't get the joy of -30F very often these days, and my wife absolutely hates those temperatures.

But in our climate it rarely even goes much below freezing, and even here we get a fairly significant hit to the range - far more than one can explain with just a change in air density.
 
R P said:
Your car's climate control is using less (if any A/C) now and not cold enough to use the heater much. But once you get below 40F, you'll notice a diff. Also, colder air is more dense, hence more drag. That however, is more linear and in San Fran you never really get very hot there, or cold, so that also has less effect where you live.
Click to expand...

Heh. It's San Francisco. I used the A/C maybe 5-6 times before our "summer" (which is Sept/Oct) ended.
 
My experience here in Eastern Ontario is a reduction of 25 to 30% in range from summer to winter. I was typically showing about 14 kWh per 100 km during the summer, not needing AC with the sunroof open. Now in late November with zero to 10 Celsius, with the same driving pattern and using the heater, it is showing about 18 kWh per 100 km. This includes Bridgestone Blizzaks replacing the OEM tires/wheels. I guess this could get worse when winter really sets in....
....Rickker
 
R P said:
Well, like I said, it depends a lot where you live. In a place like Manitoba (APU) 80F in summer and -30F in winter are not uncommon. That equates to a diff of 8000 ft in density altitude, and 25% in drag effect. I am a pilot, and for us it is well known that if we fly at 8000 ft, the air is 75% as dense as at sea level (less drag). Here is a density altitude calculator if you want to play around with it. 59F is standard temp and 29.92 is standard air pressure.
http://www.pilotfriend.com/pilot_resources/density.htm

Also your car's rolling resistance incl internal shafts/gears/bearings are also much higher at -30F. Lots working against you in severe cold.
Click to expand...
-30F or -34C before any adjustment for wind chill effect is down right brutal to even the best ICE vehicles. Fortunately my average winter is closer to -20C with only perhaps 2 or 3 weeks where it can drop into the -30s. If you have the "pleasure" of this experience in a Kona EV you will loose 40-45% of your range, your shocks will stop dampening, tires will be rock hard and your resistance heater will be running at a constant 3+Kw just to keep the windows from completely frosting over. On the upside I love how an EV will more likely start than ICE vehicle in these extremes and doesn't take 5+ minutes for the engine to heat up to get going or provide heat. IMHO, despite the range loss EVs are superior to ICE vehicles in the winter.
 
apu said:
On the upside I love how an EV will more likely start than ICE vehicle in these extremes and doesn't take 5+ minutes for the engine to heat up to get going or provide heat. IMHO, despite the range loss EVs are superior to ICE vehicles in the winter.
Click to expand...
Actually, that is a good point, too, about the loss of range with ICE vehicles.

BTW, I grew up in Manitoba and still remember well how brutal the winters are (to cars). Back then we had frost shields on the inside back windows and front sides to help with keeping a visibility hole so we could see. With the fronts, just a lot of scraping... Brrrr, just thinking about it.
 
Esprit1st said:
I have a very consistent commute and compared warm vs. cold temperature driving:

Click to expand...

Perhaps I missed something but did you mention anything about climate control? What I'd like to know is how does temp affect mileage range if climate control is not running? My GOM clearly shows a large difference in estimated range by turning climate control OFF but that's an estimate. Real world performance data is worth having. I suspect there's a "sweet spot" where climate control can be used to "moderate" interior temps and still maintain reasonably good range. When my car begins heating from stone cold the temp always seems to default to something like 75°F, which feels great but is unneeded since I'm dressed for winter conditions. I immediately set it down to around 60° since that is waaaay warmer than the outside 20°F temp. I can see the GOM move up in range incrementally as I lower the climate control temp.

What I'd love to see is a chart that compares measured outside temps to the "set" climate control interior temps with a resulting percentage change in estimated range. That would be really useful.

(Hmm. As I wrote this I suddenly realized it would be possible to do this by sitting in my driveway and recording the estimated range at different interior temperature settings. As a starting point it would be possible to make a baseline for future comparisions. I'll look into this.)
 
Yeah, I guess it depends on how important saving a couple bucks on electricity are to you. In my case, all my charging has been free so far, so Climate is on all the time, winter or summer. But even if I had to pay, for me comfort would come first. Heck, skipping a Starbucks Vente Latte would probably pay for a week of extra electricity used by Climate. Or put it another way, I would have shelled out 50K for a car if I couldn't afford to run Climate.
 
It's not the cost. I routinely charge for free too. I have a 175 mile round trip commute with zero chargers on the route. At 10°F with full heat on, lots of hills, driving in snow and darkness puts the Kona right on the margin of making it home or not. Less heat gets me more miles. I'd rather be chilly than have to walk.
 
Jgood said:
Perhaps I missed something but did you mention anything about climate control? What I'd like to know is how does temp affect mileage range if climate control is not running? My GOM clearly shows a large difference in estimated range by turning climate control OFF but that's an estimate. Real world performance data is worth having. I suspect there's a "sweet spot" where climate control can be used to "moderate" interior temps and still maintain reasonably good range. When my car begins heating from stone cold the temp always seems to default to something like 75°F, which feels great but is unneeded since I'm dressed for winter conditions. I immediately set it down to around 60° since that is waaaay warmer than the outside 20°F temp. I can see the GOM move up in range incrementally as I lower the climate control temp.

What I'd love to see is a chart that compares measured outside temps to the "set" climate control interior temps with a resulting percentage change in estimated range. That would be really useful.

(Hmm. As I wrote this I suddenly realized it would be possible to do this by sitting in my driveway and recording the estimated range at different interior temperature settings. As a starting point it would be possible to make a baseline for future comparisions. I'll look into this.)
Click to expand...
Actually I didn't use heating at all other than for a few miles when it got really cold in the car. So I used the heated seats (no heated steering wheel) for the whole drive. And I heated the cabin for a few minutes after it just got too cold for me.

During the warm time I used some AC. Probably about half of the drive.
 
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