Higher energy usage in winter?

[MrSled]

I just took my first winter drive from Nashville to Savannah and found there was a big difference between the actual miles and the rated miles used because of the cold weather. for example, My Macon GA supercharger to Chattanooga Supercharger route was 199 miles according to Google maps. I charged my model S to 245 miles in Macon GA thinking that would be enough to get me to Chattanooga but I ended up using up the entire 245 plus went 5 miles into the reserve to get to the Chattanooga TN airport charger. I made the same trip in the summer with about 10 miles to spare but in the cold weather, I barely made it. outside temps were in the mid 20's (which is cold for this time of year) and I drove roughly 70 mph the entire way with the cabin temp set at 68 degrees.

 

[AndreyATC]

Not odd at all:

1. The oil in the reduction gear adds a lot of friction when cold. - Ok, but my commute is 3 miles and car was in warm garage.

2. Cold air is denser making it harder to push though (but easier to take off if you're piloting). - Yeah, but i dont expect such variance on 30-40mph drive

3. The cold tires add a bit of rolling resistance until they have been driven far enough to warm up. - See above, car in warm garage

4. Even with range mode on, there is still some battery heating taking place. - Same as above

5. If you haven't adjust the tires upwards, the air will contract in them making them underinflated when actually driving. - I'll check the tire pressure, but doubt it's much different

I agree with your statements, but it seems they should not apply in my case

P.S. Car has beed set to ECO mode for the past a few months

 

[AnOutsider]

Yes, I need to get myself into winter mode as well. Not yet time for the snow rubber, but I do need to set the HVAC to range mode and re-check my tire pressures -- thanks for the reminder on that.

 

[dsm363]

What is general rule of thumb for putting winter tires on? When highs get below 60 but before any snow or ice of course?

 

[jerry33]

I agree with your statements, but it seems they should not apply in my case

P.S. Car has beed set to ECO mode for the past a few months

1. Try charging and pre-warming with range mode off, then switch to range mode for driving.

2. Even at 65 F, the tires aren't warm, nor is the reduction gear fluid.

3. Short distances always kill Wh/mi.

And if it's very cold, don't check the pressures outdoors. Ice will form and let all the air out (that's why you inflate inside the garage).

- - - Updated - - -

What is general rule of thumb for putting winter tires on? When highs get below 60 but before any snow or ice of course?

For most people it's one day too late However, when temperatures start to get below 45 F, that's a good time--this somewhat depends on what summer tires you have on. Another way is to watch the forecast and install when the first snow shows up in next week's weather (assumes you already have winter tires and just have to put them on).

It also depends on where you live. Some places have somewhat predictable weather and other places can change in a few hours (Calgary for example).