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Could use a different kind of cruise control

Discussion in 'Model X' started by Mrcook4590, Aug 2, 2017.

  1. Mrcook4590

    Mrcook4590 Member

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    I'm curious if it is possible to create a cruise control that works not only on speed but also takes into account whether you need to conserve battery or not, like CC2 or something. The area I was driving in this past weekend is very hilly, which is never friendly to any cruise control. I ended up driving watching energy usage more than speed because the cruise just ate up my range. I didn't drive slower than the speed limit but ended up several times going well above! My right leg was so tired by the time I got home, but I 'picked up' 5% battery, from 6% up to 11% by the time I got home. I was thinking to myself that it would be great if there was a 'conserve battery' cruise so I didn't have to concentrate so much on how much pressure I was putting on the accelerator. (My husband, who was driving his S on the same route, texted me, "Show Elon you trust the machine!" because I had wanted to stop at a destination charger to grab a little more range. If I were a tweeter, I would have tweeted that. Kind of funny now.)
     
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  2. TOBASH

    TOBASH Member

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    I have found my cruise on my 2017 P100D keeps me within 1MPH.

    I have not been on high mountains but steep hills are ok.

    I suggest not tweeting and driving. Then again I suggest never tweeting at all. I'm not a social media kinda' guy. I figure that anyone interested in what I have to say needs a better life and better role models.

    Best,

    T
     
    • Funny x 1
  3. DarkMatter

    DarkMatter Member

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    Are you new to the vehicle? Because it sounds like you would have made it home either way, and it would have been a lot less stress to just let the cruise do it.
     
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  4. flar

    flar Member

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    I've wondered if it is really advantageous to pick up speed on downhills, though. While you might think that you are banking kinetic energy, you are also increasing drag. If you let the car slow, it will use regenerative braking to get energy back. While regen is not 100% efficient, neither is feeding excess kinetic energy to aerodynamic drag because that drag is not going to give you anything back for your trouble.

    Has anyone done any controlled experiments on this?
     
  5. DarkMatter

    DarkMatter Member

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    It's advantageous in gas cars to let the speed gain happen. I suppose there would be a balance on an EV, but it's probably with less regen than you might think.
     
  6. Mrcook4590

    Mrcook4590 Member

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    No, I'm not talking about staying within a certain mile per hour range or even coasting, I'm talking about energy consumption range. Normally, cruise control on hills eats up my range. I've had the car since March but haven't made frequent long range trips - we've been on maybe four long trips, and mostly, my husband drives on long trips like this. It's probably a personality thing, but I'm not at all comfortable having only 8 miles of range left when I get to the house, but he's perfectly OK with it... trust the machine! :) I like to leave a cushion in case of accidents or road work - maybe that's a mom thing or just a neurotic thing.

    I am thinking about having a cruise control that will stay within a set of energy usage parameters instead of/along with speed. Instead of hitting the accelerator hard going up a hill, gradually doing so and keeping the energy used to a minimum. Even after all of the hills I went on, I rarely spiked to high energy usage, but it wasn't like I was going slow up the hills either. Know what I mean? I don't think I was clear in my original post. Brain fog from kids waking me up twice in the night!
     
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  7. mal_tsla

    mal_tsla Member

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    I'm not understanding how hills are so costly to range unless they're all uphill?

    I would imagine on the way up you use more power and on the way down gravity does the work and Regen captures excess momentum back to the battery?
     
  8. aesculus

    aesculus Still Trying to Figure this All Out

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    Try this thread:

    Hypermiling Technique in an EV
     
  9. Peteybabes

    Peteybabes redneck drivin' a tesla...

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    i just went to Knoxville TN from Columbus OH this past weekend which is very hilly and the last leg has Mt. Jellico to climb...my range never changed.

    what i mean by this was when i started up the mountain it said that my final destination charge level was going to be 17%, when i got to the top it said 11-12%, but by the time i got to the bottom after going down the other side it had risen back up to 16-17% final arrival SOC.

    my friend who has done the trip several times in his MS90D said he's found the same thing.
     
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  10. tezzla

    tezzla Member

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    Isn't this forum considered as Social Media? :)
     
  11. Chopr147

    Chopr147 Active Member

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    Anytime I feel a need to conserve energy I don't use cruise. It's just not as efficient as doing it yourself.
     
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  12. TOBASH

    TOBASH Member

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    Cruise control is most efficient with no other drivers on the road.

    Cruise then will be at its most efficient.

    Cruise control with stop and go traffic is not efficient, and leaves you at the mercy of the driver directly in front, HOWEVER ACC will prevent rear-ending the guy in front. You will accelerate at that front driver's speed or some pre-determined optimum rate that is set by Tesla.

    Cruise is also a defensive necessity. It locks in your maximum speed limit, preventing speeding summonses.

    I use cruise control judiciously.
     
  13. TOBASH

    TOBASH Member

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    [QUOTE... snip... Initially posted by TOBASH

    I figure that anyone interested in what I have to say needs a better life and better role models. QUOTE]

    Tezzla, You obviously need a better life and better role models... ;-)~~~~~~~~
     
  14. animorph

    animorph Member

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    I don't think TACC uses any more energy than I do going up hills at the same speed. I'm not going to coast down hills above my set speed. Not worth saving a few cents.

    The battery level at destination is not a super accurate measurement. I've had it get better and worse on different trip legs using TACC. My first leg through the mountains occasionally showed -6% battery remaining at destination as I was driving, but I ended up with 20% without slowing down. (I trusted EVTP a little too much.)

    The best way to save energy with TACC would be to set the speed lower.

    Try the same trip 10 times with TACC and 10 times without TACC, record the kWh or rated miles used, distance, and elapsed time. Then let us know the results. Currently we have one impression without TACC and no direct comparison.
     
  15. Mrcook4590

    Mrcook4590 Member

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    It a lot of uphill and not as much downhill, and the downhill sections are not steep enough to regenerate a lot of the energy lost so I end up with less than the estimated battery percentage by the time I get home.
     

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