I don't understand the SCORE

Discussion in 'Gen 4 Prius Fuel Economy' started by alanclarkeau, Jul 7, 2016.

  1. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    5,083
    5,824
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    No, not on my piano score - that's fine.

    BUT I don't understand how my PRIUS works out scores - these were 2 trips today and one yesterday. I'd have thought that the first one, with 2.8l/100km (84 US MPG) would have scored best, but only 77/100? Little traffic around, so I was able to ease off.

    But Samantha gave me a better score with the 4.0l/100km (59 US MPG) driving of 78/100. Maybe she realised there was a lot of traffic around and some hills and gave me a bonus score?

    And the best score for 3.0l/100km (78 US MPG) of 88/100. It was a steady run with one passenger and only light traffic around.

    She congratulated me with that trip for Excellent A/C scores - with 4.0l/100km the A/C was OFF the whole time!!! But with 2.8l/100 it was ON the whole time. It's winter here.

    I was driving purposely to try to get good scores in Eco Mode. I don't anticipate that being possible continually.

    One thing I've noticed is that the l/100km often goes quite high early in a trip, but gradually goes down - the middle trip started off with about 6l/100km, but gradually dropped, and that's happened with almost all trips I've taken.


    2.8 l per 100.jpg 3 l per 100.jpg 4l per 100.jpg
     
    ETP likes this.
  2. pakitt

    pakitt Senior Member

    Joined:
    Aug 10, 2009
    1,919
    1,136
    0
    Location:
    None
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    The score is not based on fuel consumption, but based on how you do 3 things - accelerate, "glide" and brake. And nothing else from what I could see. It is updated each time you start moving and each "rating cycle" is closed each time you move to a stop. When you turn off the car, it gives you the summary for that drive (I don't think it is related to the Trip you have selected).

    I don't look at it much, except for the braking - it is teaching me slowly to improve my braking which I know tends to be too aggressive. I get 5 dots already for accelerating and gliding.

    In the end, what counts is fuel consumption. Score it is a nice playful way to teach drivers to be more smooth in driving, and hence achieve better mileage (that would be valid for all cars in any case...; it's called physics :D).

    I find the acceleration indication bar in the HSI (the light blue bar that changes length as you drive around showing you how much you can accelerate "ecologically") more helpful to understand how much I can actually accelerate without affecting MPGs too much.

    All the above fuel consumptions at which temps? and how do you drive? do you pulse & glide? do you have traffic lights? what average speeds?

    As for the fuel consumption, it is higher at the beginning because the warm up sequence uses "a lot of fuel" to warm up quickly and with low pollution levels at low engine temps. A cold engine is also the most inefficient. And also because you have driven not much to average it out.
    Moreover, since the L/100km is not a linear scale (km/L is), it takes a lot more "effort" to push it down 0.1L/100km at 3L/100km than when you are at 6L/100km...see table below:
    ComsumptionPsychologyTable.png

    As you see the change in L/100km looks the same, but in fact at lower numbers, you are driving a lot more to achieve the same 0.1L/100km delta. %-wise it is practically the same because the variations are proportionally bigger as the km/L numbers are getting bigger.
     
    #2 pakitt, Jul 7, 2016
    Last edited: Jul 7, 2016
    alanclarkeau likes this.
  3. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    39,494
    10,992
    40
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    In the higher scores, you scored higher in A/C usage so that 5th bar for A/C use may have been the factor that bumped up your score. Your acceleration and gliding is the same for all 3 that you posted (Braking is better on one of them).
     
    alanclarkeau likes this.
  4. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    5,083
    5,824
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    Thanks - I guess I was thinking that the ULTIMATE criterion was l/100km. A/C was off for most of those 3 trips.

    But I can now see what it's doing - it's analysing each of the DRIVING BEHAVIOUR criteria and giving an average of the DRIVING BEHAVIOUR criteria - not the outcome of $$$ - l/100km.

    I guess the reality is that improved Driving Behaviour will improve $$$ - l/100km.

    My other observation is that using Cruise Control gives me a rap over the knuckles with a "need to improve acceleration" & "need to improve cruising". I get better scores by ignoring the tech and doing it myself.
     
    Tideland Prius and pakitt like this.
  5. pakitt

    pakitt Senior Member

    Joined:
    Aug 10, 2009
    1,919
    1,136
    0
    Location:
    None
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Yes, amazingly CC does not a good job at reducing fuel consumption - amazing as it may sound, as it has no way to know if a hill or a descent is coming up and adjusting accordingly speed and acceleration. Typically downhill I let the car roll and never brake, especially on a highway and not being an issue considering traffic, etc. The CC would brake to keep speed constant, or even accelerate in case it is not steep enough, and what would be beneficial would be to either glide or simply let the speed go a bit down, while charging the battery.
    Similar considerations when going uphill.
     
    JohnF and alanclarkeau like this.
  6. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    5,083
    5,824
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    Re "The CC would brake to keep speed constant" - I've not noticed mine attempt to brake to correct over-speed. Do you have braking including (other than regenerative braking) on your model? Hopefully it isn't something else

    I'm finding it a bit frustrating on back-roads which are up-hill and back down-hill. My diesel manuals before would mostly keep to the speed limit (70km/hr yesterday), with only occasional need to brake to bring it back on the steeper hills. But Samantha was up to 85km/hr on many of the down-hill slopes, requiring me to intervene (the POLICE here are SAVAGE when it comes to speed - only a couple of km/hr over and you've lost $$$ & licence points).

    It's fine on Motorways etc, and also when following another vehicle (if that vehicle keeps to the speed limit), the dynamic RADAR cruise control will keep a set distance from that vehicle.
     
  7. pakitt

    pakitt Senior Member

    Joined:
    Aug 10, 2009
    1,919
    1,136
    0
    Location:
    None
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Gulp, now I am doubting if it does it or not... I have to check again... I remember some (minor) braking though on Gen3...
    ACC is in any case quite smooth. And maybe a tad too slow in catching up speed. I don't know if the modes do have an effect also on ACC behaviour.
     
    alanclarkeau likes this.
  8. Mendel Leisk

    Mendel Leisk Obtuse Angler

    Joined:
    Oct 17, 2010
    34,234
    23,224
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    3rd gen with cruise on (just regular cruise) will definitely use regen braking on downhills where there car's prone to accelerate above the set speed, just due to inertia. My one concern: does it light the brake lights? Otherwise it would be a hazard if someone was following close.
     
    alanclarkeau likes this.
  9. krmcg

    krmcg Lowered Blizzard Pearl Beauty

    Joined:
    May 15, 2008
    2,282
    2,097
    0
    Location:
    Whittier, CA
    Vehicle:
    2016 Prius
    Model:
    Four
    The score was a short-term novelty to me. I appreciated seeing it at first and payed attention to it for a week or two. It seemed at times to be counter-intuitive. Better scores for lousier MPGs and such.
    Now I completely disregard it and use the MPGs alone to determine how I am doing. Maybe it trained me? Maybe not.
     
    PriUncut, JohnF and alanclarkeau like this.
  10. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    39,494
    10,992
    40
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    I think the Gen 2 is more aggressive than the Gen 3 on CC (not enough experience with the Gen 4 yet). The Gen 2 is typical CC - i.e. it maintains the speed. I think the Gen 3 allows a bit more leeway b/c of fuel economy. I suspect there must be a limit they won't cross, otherwise people might complain (or sue) that the CC isn't maintaining speed like it's supposed to.

    Depends on how hard it brakes. It's the same if you were to lightly brake vs. moderately brake.
     
    Mendel Leisk likes this.
  11. Mendel Leisk

    Mendel Leisk Obtuse Angler

    Joined:
    Oct 17, 2010
    34,234
    23,224
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I think you explained this to me before, lol.
     
  12. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    39,494
    10,992
    40
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    Possibly haha. I now recall you asking me to try it on a local hill.
     
    Mendel Leisk likes this.
  13. Gen 2 Tom

    Gen 2 Tom Active Member

    Joined:
    May 15, 2016
    333
    282
    0
    Location:
    Lincoln Park NJ
    Vehicle:
    2016 Prius
    Model:
    Three
    Mine gave me hell for poor A/C control. I do this a lot, climate on Auto with the air conditioning off. Cools the car with outside air. It makes no sense, Toyota needs look what they think is a bad non green thing.
     
    alanclarkeau likes this.
  14. JohnF

    JohnF Active Member

    Joined:
    Aug 22, 2009
    497
    419
    0
    Location:
    Essex, CT
    Vehicle:
    2016 Prius
    Model:
    Two
    I quit using CC when I discovered that the car does not go into EV when the load drops below 50%, unless the load drops on down to less than 25%. In CC, the car "hangs" in engine-on mode when the load is between 25 and 50%, which is a lot of the time. On the highway, running in EV as much as possible, cycling the battery up and down, seems to give me the best fuel economy, and CC doesn't seem to maximize EV.

    When CC is off, the load is between 25% and 50%, and the gas engine is on, assuming the battery has charge you can "nudge" the car into EV by letting up on the accelerator for a split second. Of course you can't press down too hard on the accelerator afterwards or the load will climb to >50% (there is a tiny momentary bit of slop allowed) and the gas engine will kick in again.

    Once the battery discharges to a bit below 2 bars, the gas engine kicks in to charge it. Ideally this will happen while you are on an uphill steep enough to push the load above 50% so the gas engine will fire up anyway. You can play games with this: (1) using the battery a bit harder approaching the base of a hill to pick up speed and also empty it to "make room" for more charge on the way up the hill, or (2) even if the charge is not at 2 bars as you are going up a gentler hill, consider increasing the load to induce charging that you can use later.

    I also like to nudge the car into EV just before reaching the top of a hill, letting the speed ease off just over the top and build back up on the descent, which should be in EV (you can adjust the load to 0 with your foot if you want to coast, or let up on the accelerator if regen would be useful).

    On steeper downhills I'll do regen braking rather than get going too fast, which just wastes useful energy to air drag (and money to any cops in the area).

    Today I got this, which I found amusing. On the one hand, I'm wondering what I have to do to score 100??? On the other hand, I suspect it remembers the segment where I was going (gulp!) 70mph because I was late for a Dr's appointment. I just happened to see the score, normally I ignore the score and go by mpg, which suffered due to that section. Most of this was without AC if that matters.
    96 score.JPG
     
    #14 JohnF, Jul 11, 2016
    Last edited: Jul 11, 2016
    RoadNoise and alanclarkeau like this.
  15. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    39,494
    10,992
    40
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    I don't know but I have gotten 99 and 100 before so it is possible.
     
    alanclarkeau likes this.
  16. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    5,083
    5,824
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    I think I've decided that it's unimportant - I got 2.8 l/100 yesterday on one run and 78/100 score, later I got 3.8l/100 and managed 88/100.

    But I've worked out it will give me a better score on 1) keeping the HSI in the variable blue zone (why isn't it green?) 2); maximising regenerative braking; 3) keeping out of the "FUN" zone - woops, "POWER" at the Freeway entrance; 4) driving on days which aren't too hot or cold; 5) not using RADAR Cruise Control.

    I could be wrong, but I'm not sure that "TRYING" to keep it in EV has much bearing on score, or economy, though, and the battery indicator wanders around from 1 to 7 bars as it feels - I think Samantha sorts that bit out herself.

    Still learning - I'll get there.
     
    krmcg and pakitt like this.
  17. pakitt

    pakitt Senior Member

    Joined:
    Aug 10, 2009
    1,919
    1,136
    0
    Location:
    None
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Interesting comments.
    It all depends on average speed. If I go on the highway here, I (have to) drive at the very least more than 120km/h (GPS real) - 75mph. At those speeds it doesn't matter anymore what the CC does. Last weekend I drove to Stuttgart and I set the ACC to 140km/h // 87mph...which about 135km/h real, which is totally normal for most EU highways.

    At what average speed did you get the reported fuel consumption in the pic?

    I got 100 too. I have instead a really hard time to understand how to get a high score on the braking. No matter what I do, I hardly get more than 3 dots...
     
    alanclarkeau likes this.
  18. bhtooefr

    bhtooefr Senior Member

    Joined:
    Apr 4, 2016
    1,363
    1,447
    0
    Location:
    Newark, OH, USA
    Vehicle:
    2016 Prius
    Model:
    Three
    One fun thing with the score is how it counts the cruising score.

    Accelerate at the rate that eco accelerator guidance says to, cruise at a smooth speed, lift off, brake gently, come to a complete stop, then turn, you'll get an excellent score.

    Accelerate at the rate that eco accelerator guidance says to, cruise at a smooth speed, lift off, brake gently, continue rolling, and turn, and your cruising score will take a huge hit... but you'll use less energy, because you didn't have to accelerate again. Therefore, you can avoid starting the ICE, reduce ICE load if it had to start, stay in EV longer, etc., etc.

    5 dots on the braking, from what I've seen, usually requires not maxing out the HSI's braking portion, and smooth braking with consistent HSI level (tricky, with how the brakes are mapped in the Gen 4). Your braking distances will be long when trying to get 5 dots.
     
    alanclarkeau and pakitt like this.
  19. pakitt

    pakitt Senior Member

    Joined:
    Aug 10, 2009
    1,919
    1,136
    0
    Location:
    None
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Honestly, sooner or later I will not look at the score anymore and I hope there is a way to turn off the feature completely. Because in the end the real score is the MPG. The lower the better :)
     
    JohnF and alanclarkeau like this.
  20. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    5,083
    5,824
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    With Regenerative Braking, is it true that you haven't used the Friction Brakes if you keep within the charge area without hitting the bottom of it? If so, I wonder if I've used Friction Brakes much at all, as I've rarely bottomed out the display (except to hold the car at a complete stop).
     
Loading...