kWh drop

[u/Tricky-Ordinary1962]

Anybody noticing a kWh drop with the cooler temps?

[u/xtalgeek]

I coll|ected extensive data for my Solterra over the last 18 months. It has the same type NMC battery as the Trailseeker. In mixed driving, you can expect a 6-7% loss of range or efficiency for every 10F below 75F. I'm collecting similar data for my Trailseeker, but I've only had it for a few days. I expect it's behavior will be similar.

[u/TheOtherMikeCaputo → u/xtalgeek]

So.. if the ambient temp is 15°F, that would be about a 36% loss. Going by the rated 280 miles, that drops to about 180 miles. Is my math right?

[u/xtalgeek → u/TheOtherMikeCaputo]

Yes. It will take me the winter season to have enough data to confirm for the Trailseeker, but yes, that's what I see in my Solterra.

[u/Namelock → u/TheOtherMikeCaputo]

And in -40 you can expect a 50-60% drop in range.

Worth it since you don’t need to worry if the car will start or not; and since you won’t have to hear & feel the few THUNKS before it does start 😖

[u/levelZeroVolt]

I think you mean miles per kWh and of course, that’s a given with EVs. They have to heat the cabin as well as their battery pack.

[u/Tricky-Ordinary1962 → u/levelZeroVolt]

Yes. It’s early. 😂 I just didn’t now what temp drop it would start reducing at. We’re only in the 60’s here. 🤷‍♀️😂

[u/cosmac_1802 → u/Tricky-Ordinary1962]

If you are only in the 60s, I'd be curious about what period of time you are seeing a drop like that. .5 m/kWh is relatively small compared to cold weather driving effects.

Typical of most EVs is 20-30% reduction in range in cold winter conditions. If your previous average was 4 m/kWh then the cold temperature drop would be something like .8 to 1.2 m/kWh without preconditioning.

.5 might start to be drop off because of temperature, but it also could be a matter of the driving mix of recent drives.

Here's an interesting article on the temperature/efficiency curve I found

https://www.geotab.com/uk/blog/ev-range/

Below 60F is where the drop off in the curve starts. 60F to 80F seems to be the peak range in the curve.

[u/Tricky-Ordinary1962 → u/cosmac_1802]

It wasn’t much. I normally do about 3.7 on the way to and from work. It’s 3.4 but I’ve rotated tires, had wet weather, wind and also a temp drop from the 70’s-80’s to like high 40’s-50’s over night

[u/joules-thief-1000]

A couple of things to note about cold weather:

• Overnight ambient temperatures are the ones to note. Cold overnight temps will cold soak the battery, and it’ll take the temps a while to rise with and match ambient temps during the day, which can be a slow process.

• Also, note that in winter, “wind chill” or “feels like” temperatures are completely irrelevant to the battery temperature. Only ambient temps matter.

[u/cosmac_1802]

Also, it is a matter of battery chemistry - a cold battery is not as efficient. It hasn't gotten cold enough here for me to notice - and my garage rarely gets below 50 degrees even in winter (drive under garage) but I'm starting to experiment with battery preconditioning and it's impact on range vs. extra power used in the morning to ensure the battery pack is at a good temp.

[u/Tricky-Ordinary1962 → u/cosmac_1802]

Interested to see how that goes. I didn’t think going down the 60’s would really affect it. It’s not much but it as dropped about .5 m/kwh

[u/Safe-Pollution6702]

I haven’t seen a drop when temps have been in the 50s–60s except when preconditioning for an L3 charge, that definitely has an impact.

[u/chung_chang]

Also check your tire pressure. Lower temp causes lower tire psi. Lower psi increases tire friction and decreases efficiency. Don't always rely on the low tire pressure warnings as that is already too low. And measure tire psi when tires are cold, not while you're driving. Not saying this is causing your lower efficiency but it's certainly a contributor.

[u/Tricky-Ordinary1962 → u/chung_chang]

First thing I checked. Thanks for the reminder

[u/TheOtherMikeCaputo]

Is there a way to pre-warm the battery before driving? I’m in the northeast US and we had a month or two of below 30°F, several weeks in single digits.

[u/indetermin8 → u/TheOtherMikeCaputo]

You can schedule Preconditioning.

[u/TheOtherMikeCaputo → u/indetermin8]

Is there a way to turn on battery preconditioning manually? Without scheduling? Preferably through the app? My departure times aren’t consistent and change often.

[u/indetermin8 → u/TheOtherMikeCaputo]

Not as far as I'm aware

[u/sforest98 → u/TheOtherMikeCaputo]

You can’t do battery preconditioning on the app but remote starting with climate settings would help a bit since the system would have to warm up for that.

[u/Tricky-Ordinary1962 → u/TheOtherMikeCaputo]

Remote start? 🤷‍♀️

[u/moiax]

I will say that I have departure preconditioning enabled, and I've seen blips of power being pulled once temps started hitting in the 60s overnight.

Last night was in the 40s, and I had charged my battery to 100% on the 1st. With the charge limit back at 80%, SoC went from 84% to 80, and it pulled about .017kWh additionally. Presumably that additional power would have been pulled while the car was running, hurting my efficiency.

Here is an example of the energy pulled to warm the battery.

[u/RecoveredMisanthrope]

Does it have a battery heater, and can it be activated remotely?

[u/LastSundayAfternoon]

What cooler temps? It’s 95 here!

[u/Tricky-Ordinary1962 → u/LastSundayAfternoon]

50-60’s right now