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EV Trip Planner website estimate vs. P85D actual energy use

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Everyone here seems to appreciate data, and I've been curious how accurate EV Trip Planner is in estimating energy use for the Model S. I just purchased a P85D and since the EV Trip Planner website does not have a profile specific for that model, I was even more curious to see how the this site would work for my car. Here's how I did the comparison:

EV Trip Planner site
EV Model: Model S/P (21" wheels)
Speed multiplier: 1.0
Cabin temp: 36 deg F
Exterior temp: 36 deg F
Payload: 300lbs

Payload is high. I'm 220 and there is probably only another 10-15 lbs in emergency equipment in my car, but there you go.

Car variables
The exterior temp according to my car was 31-37 degrees. I didn't use any climate control. Kept the driver side seat heater at level 2 and only used the rear defroster for about 10 minutes. Glad I remembered to bring a jacket!

I used cruise control to exactly match the average speed listed in the "Details" tab of EV Trip Planner which meant at times I was going slower than necessary on city streets but I wanted to be as accurate as possible. I accelerated gently when leaving a stop light or stop sign and when passing a truck.

Results
From my place of business to the Casa Grande supercharger (to test out charging there) was 38.3 miles with 230 feet of net elevation change (472 up and 243 down) according to EV Trip Planner. Actual mileage was 38.5
Total energy used (estimate): 14.3 kWh (374 Wh/mi)
Total energy used (actual): 15.2 kWh (395 Wh/mi)
% over estimate total kWh: 6.29%
% over estimate Wh/mi: 5.61%

From Casa Grande supercharger to my home was 57.0 miles with -115 feet of net elevation change (462 up and 577 down) according to EV Trip Planner. Actual mileage was 57.4
Total energy used (estimate): 20.6 kWh (361 Wh/mi)
Total energy used (actual): 21.1 kWh (367 Wh/mi)
% over estimate total kWh: 2.43%
% over estimate Wh/mi: 1.66%

Some conclusions that jump out at me:
1. The P85D can be driven in a way that energy efficiency is close to the P85.
2. The P85D seems to use more power climbing than is estimated for the P85. I think this data is inadequate to draw much of a conclusion, my guess is that the P85D is more power hungry climbing than a P85
3. EV Trip Planner seems fairly accurate even though there is not a P85D specific profile. I think I can trust it when I travel to Los Angeles this month.

Most importantly, it took a lot of discipline not to drive this car the way it wants to be driven :)
 
Here are my tryouts - keep in mind that last 2 trips had wind ~20-25 mph. I Have 985D with 19" Tesla Winter tires. If you use EV TripPlanner with the Tesla S/P 21" selection, it looks reasonably good at decent temperatures. The very low temperatures are completely off - both directions; trip 4 I had 563 vs 460 estimated (72 mph); return was same route at 65 mph, and I had 413 Wh/mi vs 460 estimated. This is in part due to the battery being cold (would not allow complete regen) for most of trip 4, while warm for trip 5, and possibly due to favorable wind direction on trip 5. Bottom line, in extreme conditions calculators are to be taken with caution....

speed
distance
kwh
Wh/mi
EV TripPlanner at 1.1 (for 72 mph) and 1.0 (for 65 mph)
estimated range from 100% (assuming 75 KWh available)
temp
wind
snow/rain
76
94.5
43.6
461
451
162.7
30
72
39.3
16.4
417
418
179.9
32
65
43.9
16.3
372
410
201.6
33
72
19.4
10.9
563
464
133.2
1
some
65
25
10.3
413
466
181.6
1
some