Range and Estimated Miles Question

[dees]

I just took a ~1000 mile road trip with my 2017 Model S 75D and noticed something odd.

For instance, for one leg of the journey, I drove 166 miles @ 297 Wh/mi (close to the EPA rated efficiency of 303), but my car's battery gauge went from 198 to 14 (184 miles, implying a Wh/mi of closer to ~330). Has anyone else had this issue? It occured throughout my trip.

 

[TexasEV]

It’s winter. You probably had the heat on.

 

[dees]

It’s winter. You probably had the heat on.

So the efficiency in the trips meter doesn't include the heat?

 

[N..8]

Yes and No, If you are driving the car then yes, but if it's not in Drive then No. So any heating of the battery or what not while it's in park is counting against you.

 

[dees]

Yes and No, If you are driving the car then yes, but if it's not in Drive then No. So any heating of the battery or what not while it's park is counting against you.

Interesting, the car was in drive the entire time...198 was when I disconnected from a SC and I made no stops until I got home with 14 miles to go....

 

[N..8]

Not that this will help you out now but if you pull up Trips and look at the usage from last charge sometimes this will be a little more accurate.

 

[dees]

Not that this will help you out now but if you pull up Trips and look at the usage from last charge sometimes this will be a little more accurate.

The trip counter and the usage since last charge are identical.

 

[ishareit]

Similar discussion here - Confusion regarding battery capacity

General consensus seems to be around errors in calculating regen power, discrepancy between how MCU calculates energy vs. BMS, and rounding errors.