1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Predicted EV Range Down

Discussion in 'Prime Technical Discussion' started by mr88cet, Jul 10, 2018.

  1. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    For the past month or so, I’ve seen the Toyota Guess-O-Tron’s EV range go down. In early-to-mid-April, it dropped from about 30 miles or so to ~28 miles. A couple days ago it dropped again to ~25ish.

    The interesting part though is that the *actual* range does *not* appear to have reduced much, and all in all its estimates are probably more accurate now. I’m seeing about the same number of miles left after each leg of my daily, ~19-mile commute.

    The actual range probably has gone down a *little* bit though just because of slightly greater air-conditioner load (I usually keep it at 80ish though, so probably not a huge impact).

    Anybody else seeing anything similar on your P.Primes?
     
    #1 mr88cet, Jul 10, 2018
    Last edited: Jul 10, 2018
  2. stevepea

    stevepea Senior Member

    Joined:
    Apr 16, 2017
    533
    581
    0
    Location:
    California
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Hm, not really. My Guestimate has fluctuated a bit as is normal, after doing either more city or freeway driving, but has remained pretty consistent in the same general range. At least you're still getting the same range, even if the "numbers" aren't showing it. It could be that it's noticing your increased use of the A/C and guessing you'll be using it more...
     
    #2 stevepea, Jul 10, 2018
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,156
    50,059
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    maybe it is factoring temperatures.
     
    #3 bisco, Jul 10, 2018
    mr88cet likes this.
  4. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Yes, that’s probably a big piece of it.

    I find it … wacky ... that it gives me a low climate-control score when I turn off the A/C and set it on “LO,” which of course shuts climate control off completely, so it should be the best possible score...
     
    #4 mr88cet, Jul 10, 2018
    bisco likes this.
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,156
    50,059
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    what score do you get with it on full blast?
     
    #5 bisco, Jul 10, 2018
  6. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    5,608
    3,788
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    I have an Energi and it does the same thing.

    A short trip in the afternoon when the car has been sitting all day heat soaking will use a tremendous amount of electricity per mile to cool it down and the guess-o-meter will plummet accordingly. Then the next morning, after cooling off in the garage, a 5 mile trip with much lighter a/c loads might only show a 2 or 3 mile reduction in estimated range because the trip was much more efficient (kWh per mile) than the previous hot one the day before and the algorithm hasn't accounted for that. Eventually it catches up.
     
    #6 fotomoto, Jul 10, 2018
  7. benagi

    benagi Active Member

    Joined:
    Jan 4, 2012
    525
    280
    4
    Location:
    Utah
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I saw an interesting thing this morning on my guess-o-meter. When I got in the car and put it in ready mode the EV mileage read 33 miles. I had the air on from last nite, so I went to turn it off, since I didn’t need it this morning, then my EV miles jumped to 39 miles. Wow, I’ve never paid attention what running the a/c does to your EV miles . Changed it by 6 miles before I even pulled out of the driveway. That’s almost as bad as my winter driving changes.
     
    #7 benagi, Jul 11, 2018
  8. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Curiously, I’ve only once seen the prediction change as I turn the A/C on or off. However, I have seen the number in the app somewhat higher than that on the dashboard, as if the app were accounting for air conditioning and the app’s number not.
     
    #8 mr88cet, Jul 11, 2018
  9. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I don’t know numerical scores, and I haven’t run it at full blast long enough to show the numerical score.

    However, as I adjust the temperature, it displays a five-dot indicator of how much energy it will burn. It goes up as I turn the temperature down regardless of whether the A/C is on or off.

    Sometimes, as I turn off the engine and it gives me my score, it says to choose a more-moderate temperature, even with the A/C turned off.
     
    #9 mr88cet, Jul 11, 2018
    Last edited: Jul 11, 2018
    bisco likes this.
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,156
    50,059
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    sounds like the goofy estimated mileage drop when you turn the fan on.
     
    #10 bisco, Jul 11, 2018
  11. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Yah know, I’m not so sure anymore that the *actual* range has not gone down. In fact, it may be down considerably.

    Today, charging at work, it only charged just over 5KWh. I’m pretty sure I’ve historically seen ~5.8KWh (plus or minus 200Wh or so) on a pretty-much “empty” battery (down to HV threshold).

    Actually, I had noticed lower numbers earlier, but those times, I had some residual charge (so hard to tell).

    This upcoming weekend, I’ll be taking a certain trip that has historically consumed almost exactly one battery’s charge. I’ll see if it fits anymore.

    iPad ? Pro
     
    #11 mr88cet, Jul 11, 2018
    Last edited: Jul 11, 2018
  12. zigzag

    zigzag New Member

    Joined:
    Jan 18, 2018
    21
    19
    0
    Location:
    Basingstoke, UK
    Vehicle:
    2017 Prius PHV
    Model:
    Excel
    My EV range has gone up steadily since February when i bought the car. Its seems to be in line with the temperature. In February it was showing around 25 miles after a full charge. This morning it showed 34.1. Actual range is much reduced if I use the air conditioner. I am in the UK so outside temperature in the mornings mean I can manage without A/C at that time.
     
    #12 zigzag, Jul 12, 2018
    bisco and mr88cet like this.
  13. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Perhaps, with outdoor temperatures rising (and we’re talking Texas here, so highs in the high-30s Celsius), Toyota is intentionally reducing the total charge of o keep from impairing battery life. In other words, increasing the charging margin at the top.
     
    #13 mr88cet, Jul 12, 2018
  14. zigzag

    zigzag New Member

    Joined:
    Jan 18, 2018
    21
    19
    0
    Location:
    Basingstoke, UK
    Vehicle:
    2017 Prius PHV
    Model:
    Excel
    My guess is that the battery has an idea operating temperature and in the UK winter time (0 deg C) I'm below it and in the current UK summer time (20 deg C at the time I drive to work) I'm about optimum. It has been hotter here recently, but in the afternoon and by then I'm using the internal combustion engine as I have no place to plug in at work.

    Maybe I'll try driving to work on the petrol engine tomorrow and see if the range is better or worse in the hotter afternoon temperature.
     
    #14 zigzag, Jul 12, 2018
    mr88cet likes this.
  15. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,311
    1,335
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    That would be an interesting comparison, although if there’s an elevation change on your commute, that could confuse the results. Traffic conditions potentially as well.
     
    #15 mr88cet, Jul 12, 2018
(You must log in or sign up to post here.)