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No, It’s Real: EV Range Down

Discussion in 'Prime Technical Discussion' started by mr88cet, Jul 12, 2018.

  1. tpenny67

    tpenny67 Active Member

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    Hopefully some hysteresis in the system, so you can continue to gain as the temperatures continue dropping!
     
  2. mr88cet

    mr88cet Senior Member

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    Hopefully...

    Still, a pretty big drop from 31-32ish a mere 5 months ago.

    On the upside though, I can still get to most of the places I need to go day-to-day strictly in EV mode. When it was down to 25 miles, one twice-a-week destination didn’t quite make it...
     
  3. bisco

    bisco cookie crumbler

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    what has the average temp been?
     
  4. john1701a

    john1701a Prius Guru

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    What data have you collected ?

    Seeing daily efficiency results (especially miles/kWh) would be informative. Without any detail, it's just wild guessing.

    You want to do it right, use Hybrid Assistant. The automatic reporting tool it provides collects a ton of easy to share data.
     
  5. mr88cet

    mr88cet Senior Member

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    Evenings have gone as low as the lower-mid-70s, although that only for the past few days, more typically mid-80s.
     
  6. mr88cet

    mr88cet Senior Member

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    Data above: Charging 5.3-5.4 KWh from the HV threshold to full, estimated range from 25.x to 27.x miles.

    No substantial difference in efficiency as far as I can tell — still on the order of 4.7 miles/KWh.

    Hybrid Assistant = ?
     
  7. john1701a

    john1701a Prius Guru

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    You're not actually collecting any data, it's just anecdotal observations.

    Detail, like battery temperature, is vital for understanding what's happening.

    The phone-app provide that.
     
    #87 john1701a, Sep 11, 2018
    Last edited: Sep 11, 2018
  8. mr88cet

    mr88cet Senior Member

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    Well, amount charged is hard data, although, yes, I agree that doesn’t say much about *why* those data values are down. Typical outdoor temperatures that I’ve reported might give hints.

    I have a Carista thingie, but unfortunately haven’t had a chance to plug it in yet... BZ

    “Phone app” = “Hybrid Assistant”?
     
  9. bisco

    bisco cookie crumbler

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    you're still a little warm. are you charging in a garage?
     
  10. mr88cet

    mr88cet Senior Member

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    I keep the car in one garage or another most of the time and, yes, almost always charge it in the garage at home or in a covered parking garage.
     
  11. bisco

    bisco cookie crumbler

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    my garage is sometimes pretty warm.
     
  12. mr88cet

    mr88cet Senior Member

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    Ours at least is quite a bit cooler than outdoors.
     
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  13. mr88cet

    mr88cet Senior Member

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    Hmmm... The guesstimatron is up to 28.7 miles this time around. Unfortunately, I don’t know exactly how many KWh, since I didn’t discharge it quite to the HV threshold. Well, actually pretty darned close though: I discharged it down to 0.3 miles, and it charged 5.433KWh.
     
  14. john1701a

    john1701a Prius Guru

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    You have the data. The dashboard screen provides efficiency and distance traveled. Just do the math.
     
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  15. mr88cet

    mr88cet Senior Member

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    Mostly letting you folks hear what I’m seeing, since you folks haven’t seen this huge of a drop (yet at least!). “War stories,” so to speak. That, to give you an idea what you might see if any of you end up following in my footsteps!

    It’s been reading 4.7 miles/KWh pretty consistently since I got it, and at least a rough manual calculation concurs that it should indeed be in that range.

    The question is why it decided to stop charging as much, in particular in three distinct steps, from which it’s now gradually creeping back up. It’s highly likely that summer temperatures were at least one reason why it dropped.

    Well, actually, what I most am wondering about is whether and how much of the 32ish original range I’ll eventually get back. That might just be a “time will tell” kind of thing.
     
  16. bisco

    bisco cookie crumbler

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    do you have any records of actual max ev distance?
     
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  17. mr88cet

    mr88cet Senior Member

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    (Reasonable question.) Not actual EV range, in detail.

    BTW, this is the first time in 4ish months I’ve gotten home, after charging at work, and still had more than 10 miles of (predicted) EV range left. Before this strange drop, it had been more like 12ish.
     
    #97 mr88cet, Sep 12, 2018
    Last edited: Sep 13, 2018
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  18. mr88cet

    mr88cet Senior Member

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    Today was a curious case, and I think it’s more or less along the lines of what Bob mentioned:

    I came coasting in to work on electron fumes (insert joke about Heisenberg and electron “clouds”). No chargers were available, so I parked it with 0.1 miles to spare.

    When a charger came available and I fired it up to move it over to the charger, the Guesstimatron said 1.2 miles. Wanting to get a reading on it, I drove it ... less than “around the block,” until the ICE kicked in. I then plugged it in.

    When it finished charging, the GoM estimated 27.5 +-0.2 miles (I forget the exact number). That’s less than the 28.7 estimate this morning after charging overnight. However, the interesting part is that ChargePoint reported charging 5.755KWh, which is considerably more than the 5.43KWh charged yesterday, and a lot more than I’ve seen for quite a while.
     
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  19. mr88cet

    mr88cet Senior Member

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    Well now, this is interesting: Charging an extra 0.32KWh probably didn’t translate to longer EV range; probably just compensated for the extra mile or so I drove to ultra-deplete the battery. I landed at home with only about 5 miles of range rather than 10 miles yesterday.

    The biggest difference was that traffic went faster today, so more wind resistance and more power required.
     
  20. m8547

    m8547 Senior Member

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    I thought I was having the same problem. I live 15 miles form work, so I can usually just barely make it home on EV without charging at work. I can't make it if I use the AC too much, or if I drive slightly more aggressively. Recently the weather has become mild, so I haven't needed the heat or AC. But I was getting to work with only about 40% charge left, despite careful driving. Going home is slightly more downhill, but that's not quite enough to make it.

    It turns out my tire pressure was just low! After 3 months and about 30 degree lower temperatures it had gone from 36-ish to 30-ish. I inflated my tires last night, and made it to work with 49% charge remaining today, which is plenty to make it home if I drive carefully.

    I don't have any good way to measure energy consumed while charging, so I can't see how much is going into the battery.
     
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