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

Optimal Driving Mode Select and EV/HV drive mode combo?

Discussion in 'Prime Fuel Economy & EV Range' started by IABoy987, May 20, 2020.

Tags:
  1. IABoy987

    IABoy987 Member

    Joined:
    Nov 25, 2011
    180
    76
    0
    Location:
    Iowa
    Vehicle:
    2018 Prius Prime
    Model:
    Plug-in Base
    I looked through several pages of this forum but did not see quite a specific answer.

    Wife and I read and re-read the manuals for Driving Mode Select (normal,power mode, eco driving mode) and EV/HV drive mode (EV mode within/not in a box, EV auto), and not sure what is optimal settings. In Iowa its mostly "flat land driving" as such no serious hills or mountains to climb. We know that we don't need power mode as there is just two people in car and we don't pass everything on the road, driving nice and easy at speed, in no hurry.

    We concluded that ECO drive mode and EV auto should be best combo (let those $$$ computers figure it out ;)). What have you experienced Prime owners found to be the best setting combo? :)
     
    Tips likes this.
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    there is no one best setting, it's multi factorial. and tbh, there's no big difference for any of them.

    ev keeps you in ev when you want it to.

    ev auto lets the computer decide.

    hv runs the engine more an little ev.

    eco is to help people improve their mpgs by remapping the throttle sensor, but uses the same power by pushing harder the power mode.
    there is no more power available in power mode, it just comes faster with a lighter touch of the pedal.

    if your main concern is saving a few sheckles, compare the cost of gas and electricity, and use the cheaper fuel.
     
    MTN and IABoy987 like this.
  3. schja01

    schja01 One of very few in Chicagoland

    Joined:
    Apr 22, 2005
    1,731
    1,154
    0
    Location:
    Chicagoland
    Vehicle:
    2018 Prius
    Model:
    Prime Advanced
    For me EV Auto is of little value. It basically runs EV until the battery depletes and then goes HV. This to me is what leaving it in EV initially does. To each their own.
     
    jerrymildred and IABoy987 like this.
  4. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    10,958
    8,836
    0
    Location:
    New England
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Unless I am driving on a busy city highway, Eco mode works fine for me. I switch EV and HV modes back and force to improve EV efficiency unless my trip is short enough to finish all EV. As stated, EV Auto has no value in my driving situation.
     
    IABoy987 likes this.
  5. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,306
    1,328
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I haven’t used EV Auto much (in fact, I don’t think I’ve ever used it in the 3 years we’ve our Prime!), but my *impression* is that it works much like the original Prius Plug-In: it drives on EV all the time, except that it kicks in the engine to assist the motors when you accelerate hard, to keep from expending the battery charge quite so quickly.

    I’d say the best way to drive would be, basically, just drive; it does a great job of figuring out the best usage on its own. However, if you want to get more involved in it, I’d suggest: If you can take your trip entirely on electric, then do so. If not, then stay on electric at low speeds, and kick in HV once you’re mostly cruising.

    The mode I *wish* it had instead of EV Auto is what might perhaps be called “HV Auto“: In this hypothetical mode, it would behave exactly as it does in HV mode, except that it imposes an absolute lower limit on instantaneous MPG. That is, it drives in plain HV, except that if at any instant in time it needs to add power from the ICE, and if doing so would drop your instantaneous MPG below, say, 50MPG, it sources that power from the battery instead.
     
    #5 mr88cet, May 20, 2020
    Last edited: May 20, 2020
  6. eatriceyo

    eatriceyo Member

    Joined:
    May 12, 2020
    45
    31
    0
    Location:
    Honolulu
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    leave the car in normal mode and use ev driving when you're in the city. definitely use cruise control for long drives to maximize mpg.
     
    mr88cet likes this.
  7. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,549
    719
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    If you really want to minimize fuel use, and your trips are regularly long enough that you can't make it in EV mode, using HV mode for acceleration and hills and EV for cruising and downhill will maximize your overall efficiency.
     
    Raytheeagle likes this.
  8. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,474
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    +1;).

    That's what I do everyday for my 38 mile each way trip to work:).

    Over 23k miles (which includes longer trips) I've averaged 139.7 mpg. Blend the modes to maximize efficiency(y).
     
  9. PiPLosAngeles

    PiPLosAngeles Senior Member

    Joined:
    Nov 18, 2012
    1,549
    719
    0
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    It took me a year of careful trial and error to confirm that is the best overall strategy. Now my problem is that if I use HV for every start and every hill I will return home with significant amount of EV remaining, which is suboptimal. Before all the lockdowns I was experimenting with only using HV when accelerating uphill or driving uphill.

    EDIT - My pipe dream for a plug-in is to have a programmable EV AUTO mode, where I can set the switchover point based on engine load. Even if they dummied it up and just let you set some kind of bias towards EV or HV (like setting an arbitrary number from 1 to 10, with 1 being staying in EV under all conditions and 10 being staying in HV under all conditions), it would greatly improve efficiency.
     
    #9 PiPLosAngeles, Jun 13, 2020
    Last edited: Jun 13, 2020
    Tips and Raytheeagle like this.
  10. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,474
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    I don't do it for every incline, but I make sure at each end of the work trip I finish at 1% or less;).

    So the steepest inclines get HV and the more gradual ones get EV mode:).

    My charging at work is free, so I ensure that I get there near empty and since I work kore than 8 hours, leave full(y).
     
  11. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    10,958
    8,836
    0
    Location:
    New England
    Vehicle:
    Other Hybrid
    Model:
    N/A
    For optimal overall mpg using EV and HV mixed and switched, the daily drive has to be substantially longer than the EV range. I think 70-80miles is the best distance to get most out of and EV (high miles/kWh) and HV (high mpg). With my commuting of 36 miles round trip and no charging opportunity at work, I can make almost home all on EV during summer. If I use HV for the portion of this commute on the start-up, accelerate, and uphill, I can get extremely good EV efficiency, but will end up not using all of the charge and substantially lower mpg than just driving EV until it depletes to zero.
     
  12. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    44,767
    16,015
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    My daily drive is within EV range so it’s Eco mode with Eco Heat/Cool and S-Flow Auto and EV Drive Mode.

    My area has free public charging so if I need to extend my range, I can top off within an hour while I do errands. Less so now given the current conditions and the fact I have a full tank of gas so I’m not as picky when the engine comes on.
     
    jerrymildred likes this.
  13. NSXT

    NSXT Active Member

    Joined:
    Sep 13, 2018
    137
    117
    0
    Location:
    Toronto, Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    To maximize EV I use the following flip combo:
    EV = local, downhill
    HV = highway, uphill

    If wife drives, just drive and do nothing :ROFLMAO:
     
    douglasjre and benagi like this.
  14. schja01

    schja01 One of very few in Chicagoland

    Joined:
    Apr 22, 2005
    1,731
    1,154
    0
    Location:
    Chicagoland
    Vehicle:
    2018 Prius
    Model:
    Prime Advanced
    Which is probably how Toyota engineers designed the car to be driven.
     
    Tips and jerrymildred like this.
  15. Tips

    Tips Member

    Joined:
    Dec 22, 2019
    128
    64
    0
    Location:
    Grand Forks, B.C. Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Plug-in Base
    I've started using ev auto in eco mode . The Prime in ev auto decides the mode. My last trip 110 kilometers there and back with two passes over 5200 hundred ft.. The trip was from Grand Forks, BC. too Trail, BC and return! I started with 30% charge (not on the ball) and started with hv mode to warm the ice up! After five min. I hit the ev auto twice. On the 15kilo hill down too Trail I switched too b mode and managed too get 40% full pack. On the return trip ( same route in reverse) I kept the car in ev auto! When I arrived home I had 10% ev! My trip was a total off 220 kilometers and the fe was 3.1 kil per 100 kilometers or 75 mpg .

    Posted via the PriusChat mobile app.
     
    Tideland Prius likes this.
  16. Tips

    Tips Member

    Joined:
    Dec 22, 2019
    128
    64
    0
    Location:
    Grand Forks, B.C. Canada
    Vehicle:
    2020 Prius Prime
    Model:
    Plug-in Base
    Probably the best thing you can do is to keep your speed at 60 mph in the flat country and watch the high mpg you can get. It will surprise you. This car can be amazing if you smell the and enjoy the ride!

    Posted via the PriusChat mobile app.
     
    samlarson and Tideland Prius like this.
  17. samlarson

    samlarson New Member

    Joined:
    Aug 18, 2020
    5
    2
    0
    Location:
    Clifford
    Vehicle:
    2016 Prius
    Model:
    Two
    Yeah, that what I usually do
     
    Tips likes this.