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What Mode should i use to go up/down the hill...

Discussion in 'Prime Fuel Economy & EV Range' started by prius4owner, Feb 26, 2018.

  1. prius4owner

    prius4owner Member

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    I live on the hill. It is about 5 miles drive all going up the hill.
    My question is what mode should i use to drive up and down the hill for my daily commute.
    Any strategy to maximize the MPG ?
    Also, i noticed that it charge about 9% battery when i go down the hill for work.

    Thanks
     
  2. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    B mode all the way down.
     
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  3. Lucifer

    Lucifer Senior Member

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    The traction battery is charged already as you go down the hill, so enjoy, the ice will come on in the first 5-10 minutes, just bear it, as you go about your drive save some traction battery to get back up the hill, if you have 15miles left, use the ice for steep slopes and the traction for less steep, just assuming you are driving 40 miles on your commute, D is unnecessary driving down, you're already charged.
    If the five miles uphill is at 55 mph, save the 20-30 traction miles for the uphill drive.
     
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  4. Prime8

    Prime8 Member

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    If the up hill is at the beginning of the drive, use EV Auto.

    If the down hill is at the beginning of the drive, and like me, you fully charge the battery, since there is no other option, use EV. If you want to stop regen from starting the engine, because the battery is already full, the only suggestion that I have heard to keep the engine off is to use Neutral and brake during the down hill parts until you have used some of the battery capacity, then EV.

    I have used B mode, on occasion, but it tends to bring the engine on more easily. I have used B mode around town, and it prevents the engine from turning off at stop lights when the battery is in HV mode(bottom 1/3). Use B mode with discretion.

    For mountains and some hills, HV up, EV down. Regen can add 8-9 miles of EV range per 1000' of elevation drop. EV does not climb mountains efficiently.
     
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  5. muleman

    muleman Junior Member

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    I love the neutral roll.
     
  6. Prime8

    Prime8 Member

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    I finally got a chance to use the neutral roll today, and the ICE successfully failed to come on. This saved me the fuel of the warm up since the trip was short.
     
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  7. Wuzki

    Wuzki Member

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    Turn on ev auto mode for extra power. If not hv mode is best for uphill. I don’t see any good mpg for going up hill unless you had ev mode on.
     
  8. CraftyCoder

    CraftyCoder Member

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    I did some ROUGH calculations on strictly the energy used to drive your roughly 3600 pound car up a hill. Ignoring all inefficiencies(which is a major over simplification), you will still use about 1.4 Kwh for every 1000 feet of elevation gain.

    Since this is about 20% of your available charge(6.5 Kwh), it translates to about 5-7 miles on a level surface. So as a rule of thumb delete about 5 miles of your range for every 1000 feet of elevation gain. Of course, you get much of this back on the down hills.
     
  9. E-GINO

    E-GINO Active Member

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    Well, if I were you, I'd program the charge at home in such a way it will not be completed at the time you usually leave, i.e. if you leave at 0730 am you could instruct the car to complete the charge by 0815 am. This precaution should leave enough room in the traction battery to complete the charge going downhill.
     
  10. Roy2001

    Roy2001 Active Member

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    When you leave home, only keep partial charged. When you climb the hill, keep at lease 5 miles electricity.