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P85D vs. P85 Efficiency Testing, Take 2

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wk057

Former Tesla Tinkerer
Feb 23, 2014
6,504
17,139
X
Update:
Final results!

P85: 111.3 miles, 35.0 kWh, 315 Wh/mi
P85D: 112.3 miles, 35.4 kWh, 316 Wh/mi

For comparison, the results of the previous test (pre-torque sleep) were:
P85: 111.3 miles, 34.1 kWh, 306 Wh/mi
P85D: 112.2 miles, 39.5 kWh, 352 Wh/mi

----------------

So, I did a preliminary test of the new firmware received this evening (v6.1 2.2.140) immediately and the results are very promising. Enough that I'm going to make sure that I talk my fiance into doing an updated side-by-side test with her P85 tomorrow like in my previous thread and video. She is returning early from a short trip, so, could work out!

Should be about the same conditions and route as last time.

Differences being:
  • that this time I will use TACC to pace the P85 instead of setting cruise to the same value and then having the P85 slowly pull away over the miles like it did last time (some reason the cars couldn't maintain perfect cruise sync)
    • No way to disable TACC or fall back to the old style cruise.
  • the P85D having torque sleep now
  • 1000+ miles more on both cars/tires than last time

Hoping to try this tomorrow afternoon, heading to the same Japanese restaurant for lunch. ;)

If I'm right in my estimates based on my ~35 mile drive tonight the P85D will use less energy than the P85 this time...

So, for the first fun part, here are the details of the test trip I did alone that have convinced me a new side-by-side is needed:


  • Total trip was 34.8 miles, 11.1 kWh, 318 Wh/mi
  • Battery was a little cold for the first part with regen limited around 35kW.
  • Trip included a single 0-60 insane/non-range mode launch
    • According to timing from my video, no improvement on this front yet and same power consumption as before according to the dash
      • That's not what I was going for tonight anyway. Just tested for completeness ;)
  • Rest of trip was Sport/Range Mode
  • ~6 miles of rural and in-town driving.
    • This leg is somewhat uphill
    • Last several trips on this stretch were 500+ Wh/mi in the P85D.
    • I reset trip B after the 0-60 launch (1.5 miles into this stretch) and the remaining 4.5 miles yielded a respectable 369Wh/mi, roughly on par with the P85.
  • Jumped on the interstate and set cruise at 65 MPH (minor interuptions due to TACC slowing as people moved around)
    • First 14 miles were a slight net uphill yeilding 319Wh/mi.
      • The first 3 miles of this part of the trip were < 180 Wh/mi!
    • Turned around, reset trip B
    • Return 13 miles were a slight net downhill yielding 233 Wh/mi.
    • Average for the round trip on the highway at 65 MPH: 277 Wh/mi.

First, I've never seen a Wh/mi in the 200s on the P85D... ever. Not even on short stretches. Second, this same trip (just about) I did in the car a few days ago at ~430 Wh/mi.

I'm impressed so far. Regen/coasting seems to work much more efficiently than previously. I noted a few times during the first side-by-side test that at some points the P85 would be in regen while the P85D was either still using power or barely breaking even on power. The P85D seems to so better with this now. I was seeing slight regen even on small downward inclines with cruise set. Pretty cool.

Additionally, I did note three independent instances of hiccups in the new firmware, all at < 10 MPH and while turning sharply and decelerating. (I'll be sending a note to Tesla after I finish this post.) Into my driveway, a U turn, and a left turn on to the highway on ramp. For anyone who has driven a manual ICE car, it felt like a sloppy downshift. Like if I had let the clutch out too fast when downshifting. I'm guessing this may relate to one of the motors engaging or disengaging it's regen at the time and not being smooth about it. Was exactly the same all three times. Probably pretty repeatable. In the final instance when I was turning right to prepare to back into my driveway I felt what I believe were the front wheels skip as it happened, as if they had locked or slowed substantially for a moment (split second).

Overall... seems like a very promising update. Can't wait until tomorrow! *puts GoPros on charge*

Edit: It is worth noting: At 277 Wh/mi that is roughly 270 miles @ 65 MPH (using the highest usage I've seen out of my P85's battery at ~75kWh). Consider the elevation changes in my @ 65 MPH test legs and factoring for the efficiency of regen... I think the original quoted 285 miles @ 65 MPH number may be completely doable on flat terrain.
It is also worth noting that I beat the P85D rated miles on this trip by several %. Usage was closer to (P)85 rated miles...
 
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  • Informative
Reactions: tedsk
So, I did a preliminary test of the new firmware received this evening (v6.1 2.2.140) immediately and the results are very promising. Enough that I'm going to make sure that I talk my fiance into doing an updated side-by-side test with her P85 tomorrow like in my previous thread and video. She is returning early from a short trip, so, could work out!

Wow, this is awesome to hear, and thanks for all of your testing and postings on this topic. I have been traveling the last few days while my P85D sits at home in the garage waiting for me to start the update. The timing of this couldn't be better as I have to make a roadtrip to Detroit on Friday night, and the range increase will be very welcome. Last road trip to Detroit to attend the special Tesla NAIAS event turned into a bit of a charging nightmare for me between the subzero temperatures and "insane" energy use.
 
This is just awesome. A few days I was ready to downgrade my close-to-production P85D to an 85D, because of all the reported range issues (and your original comparison video). It looks like I get to keep the P after all!!! Thanks for the detailed report, and looking forward to the new comparison video 2.0.
 
@wk057, waiting with bated breath! Thank you for dedicating so much time and effort! My P85D is still on .139 and haven't had much chance to test it. Most of my driving has been in the city and I can't say I've seen much improvement. I'm hoping highway driving and .140 yields better results. Looking forward to your findings!
 
This is horribly unscientific, but for what it's worth, I've noticed an improvement in range on my P85D since the update. On the commute to downtown SF from the outer reaches of the East Bay, a 90 or so mile r/t with some nasty traffic, what used to use up about 100 miles of range now uses 92 or so.

I know, it's the wrong metric to really know what's going on, but I didn't even realize there had been an update and hadn't been tracking the WH/mi on this trip previously.
 
My unscientific observation after loading .140 this evening is I took a 120 mile roundtrip (60 miles each way) and don't see any noticeable improvement. 48 degrees F, no wind, all interstate with speed varying between 60 and 70 MPH. Range Mode = ON. Used 355 Wh/mi. Would have been about 300-310 Wh/mi in my P85+ with Range Mode OFF.

Obviously I won't pass judgement until I'm able to log more miles under varying conditions but my initial impression is not good.
 
I can't speak for any improvements between .139 to .140 because I never received .139 and went straight to .140. I can, however speak about improvements between delivery and .140. :)
 
Additionally, I did note three independent instances of hiccups in the new firmware, all at < 10 MPH and while turning sharply and decelerating. (I'll be sending a note to Tesla after I finish this post.) Into my driveway, a U turn, and a left turn on to the highway on ramp. For anyone who has driven a manual ICE car, it felt like a sloppy downshift. Like if I had let the clutch out too fast when downshifting. I'm guessing this may relate to one of the motors engaging or disengaging it's regen at the time and not being smooth about it. Was exactly the same all three times. Probably pretty repeatable. In the final instance when I was turning right to prepare to back into my driveway I felt what I believe were the front wheels skip as it happened, as if they had locked or slowed substantially for a moment (split second).

I absolutely experienced the same thing (I have .139 btw). My neighbors thought I was nuts as I rolled through my neighborhood going between 3-8 mph as I tested this thing "shift" over and over again. During slow "acceleration" you could clearly feel it shift, and when letting off the pedal under 10 mph it feels as though the regen kicks in hard, then smooths out. Not noticeable at higher speeds, but in a crawl you can definitely feel it.

As for the range.. the improvements are great. Had a 54 mile round trip today that would typically run me around 370-400 kW/mi. This time around it was 270. I'll take the shift issue all day for that range. Very happy.
 
I absolutely experienced the same thing (I have .139 btw). My neighbors thought I was nuts as I rolled through my neighborhood going between 3-8 mph as I tested this thing "shift" over and over again. During slow "acceleration" you could clearly feel it shift, and when letting off the pedal under 10 mph it feels as though the regen kicks in hard, then smooths out. Not noticeable at higher speeds, but in a crawl you can definitely feel it.

As for the range.. the improvements are great. Had a 54 mile round trip today that would typically run me around 370-400 kW/mi. This time around it was 270. I'll take the shift issue all day for that range. Very happy.

Good to know I'm not crazy... and I did pretty much the same thing (after I got back and posted this thread) in front of the house.

Definitely something noticeable, but yeah I'll take it vs the old efficiency.
 
My unscientific observation after loading .140 this evening is I took a 120 mile roundtrip (60 miles each way) and don't see any noticeable improvement. 48 degrees F, no wind, all interstate with speed varying between 60 and 70 MPH. Range Mode = ON. Used 355 Wh/mi. Would have been about 300-310 Wh/mi in my P85+ with Range Mode OFF.

Obviously I won't pass judgement until I'm able to log more miles under varying conditions but my initial impression is not good.

@NOLA_Mike: I wonder why your experience is so different from that of everyone else who's reported efficiency improvements under .139/.140? It seems very odd, and I hope we can find a good explanation in the end.
 
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I wonder why your experience is so different from that of everyone else who's reported efficiency improvements under .139/.140? It seems very odd, and I hope we can find a good explanation in the end.

I'm not really sure, but, like I said... I've never seen Wh numbers in the 200s driving around here, ever, in the P85D... let alone ~233 Wh/mi over a dozen miles.

Looking more closely at my highway stretch:

The westbound part shows a net elevation change of +203 ft over ~14 miles. EV Trip Planner says 361 Wh/mi at 65 MPH. I achieved 319. (Included exiting the hwy and turning around)

The eastbound part (which was a hair shorter because I exited at a different exit) shows a net elevation change of -190 ft over ~13 miles. EV Trip Planner says 306 Wh/mi at 65 MPH. I achieved 233. (Included exiting the hwy and parking in a parking lot)

2015-02-04 20.00.28-cropped-desc.jpg


Interestingly enough the 15mi avg matched the Trip B avg for that eastbound stretch.

In between cruise was set at 65. This isn't a flat highway, many ups and downs. (I-40 a bit east of Asheville, NC)
 
The westbound part shows a net elevation change of +203 ft over ~14 miles. EV Trip Planner says 361 Wh/mi at 65 MPH. I achieved 319. (Included exiting the hwy and turning around)

The eastbound part (which was a hair shorter because I exited at a different exit) shows a net elevation change of -190 ft over ~13 miles. EV Trip Planner says 306 Wh/mi at 65 MPH. I achieved 233. (Included exiting the hwy and parking in a parking lot)

Interestingly enough the 15mi avg matched the Trip B avg for that eastbound stretch.

In between cruise was set at 65. This isn't a flat highway, many ups and downs. (I-40 a bit east of Asheville, NC)

Hahahaha. That's flat. :)

The test loop that I've been doing starts with -220 ft over 1 mile, followed by +500 ft over 5 miles, then flat for 2 miles, then back again. Like I said, it's hilly here.

Perhaps that's why I'm not seeing any improvement with .139, with Range Mode on or off. With all of this elevation change, maybe the rear motor isn't getting a chance to idle.

@NOLA_Mike: I wonder why your experience is so different from that of everyone else who's reported efficiency improvements under .139/.140? It seems very odd, and I hope we can find a good explanation in the end.

NOLA_Mike, what sort of terrain are you driving over? Hilly?
 
@NOLA_Mike: I wonder why your experience is so different from that of everyone else who's reported efficiency improvements under .139/.140? It seems very odd, and I hope we can find a good explanation in the end.

Needless to say, I'm disappointed. I even rebooted the system at the midpoint of my drive to see if that would help on the return trip. I probably won't get a chance to test anything today but will be doing extensive testing over the weekend.

If everybody else gets dramatic improvement on .139/.140 then I guess I have to consider the possibility of something hardware related/wrong with my car that is not allowing the torque sleep to activate.

Mike

- - - Updated - - -

NOLA_Mike, what sort of terrain are you driving over? Hilly?

I-12/I-10 in south Louisiana - doesn't get any flatter than that... :)
 
The eastbound part (which was a hair shorter because I exited at a different exit) shows a net elevation change of -190 ft over ~13 miles. EV Trip Planner says 306 Wh/mi at 65 MPH. I achieved 233. (Included exiting the hwy and parking in a parking lot)

That is crazy talk! 233?! I didn't even think that was possible in a P85D. I'm sure hoping I see something like that when I get a chance to do some testing. That's very impressive.
 
If everybody else gets dramatic improvement on .139/.140 then I guess I have to consider the possibility of something hardware related/wrong with my car that is not allowing the torque sleep to activate.

I'm pretty sure I'm going to be joining you in the no or little improvement category, NOLA_Mike. I hadn't posted yet because my trip yesterday was into a head wind, and not exactly one that is taken quite as regularly as my wife's almost daily drive into work that she took this morning. I had her document that, and I'm going to compare the numbers to EV Trip Planner before posting, but based on other trips, I'm pretty sure we've seen little or no improvement. The only real variable is that I now have the ability to monitor windspeed, thanks to the new tool discussed in this thread: Tool to estimate the head wind while driving !

I didn't have that before. Today she was driving into a headwind of 5-7 MPH for some of the time. But I imagine that was true of some of her other trips as well.

I'll write up something more detailed when I have some more time later, but I just didn't want you to think you were all alone. I'm pretty sure you are not.

I have .139, but not .140, and have only taken those two trips with it.
 
So, for the first fun part, here are the details of the test trip I did alone that have convinced me a new side-by-side is needed:


  • Total trip was 34.8 miles, 11.1 kWh, 318 Wh/mi
  • Battery was a little cold for the first part with regen limited around 35kW.
  • Trip included a single 0-60 insane/non-range mode launch
    • According to timing from my video, no improvement on this front yet and same power consumption as before according to the dash
      • That's not what I was going for tonight anyway. Just tested for completeness ;)
  • Rest of trip was Sport/Range Mode
  • ~6 miles of rural and in-town driving.
    • This leg is somewhat uphill
    • Last several trips on this stretch were 500+ Wh/mi in the P85D.
    • I reset trip B after the 0-60 launch (1.5 miles into this stretch) and the remaining 4.5 miles yielded a respectable 369Wh/mi, roughly on par with the P85.
  • Jumped on the interstate and set cruise at 65 MPH (minor interuptions due to TACC slowing as people moved around)
    • First 14 miles were a slight net uphill yeilding 319Wh/mi.
      • The first 3 miles of this part of the trip were < 180 Wh/mi!
    • Turned around, reset trip B
    • Return 13 miles were a slight net downhill yielding 233 Wh/mi.
    • Average for the round trip on the highway at 65 MPH: 277 Wh/mi.

First, I've never seen a Wh/mi in the 200s on the P85D... ever. Not even on short stretches. Second, this same trip (just about) I did in the car a few days ago at ~430 Wh/mi.

I'm impressed so far.

I'm jealous! I have .139 and did a test run this AM.

I ran approx 50km on mixed flat and mildly rolling hills, clear dry pavement with cruise control on, 58mph, sport mode. Car was fully preheated, in a heated garage and I ran it in range mode.

Average consumption: 488Wh/mile. I'm sure the temperature is a factor. Thermometer on the dash read -32C which is roughly -26F. Ugh.... I'm looking forward to March. That said, I haven't seen any noticeable improvement from .113 to .139.
 
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