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

ALL EV Modes explained

Discussion in 'Prime Technical Discussion' started by Bobenhaus, Sep 4, 2017.

  1. Bob Comer

    Bob Comer Active Member

    Joined:
    Sep 20, 2010
    708
    456
    0
    Location:
    South Carolina low country
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Of course it knows my destination, it's been keeping track of my commute and that's all it has to do, act like it's my commute until some kind of deviation cancels it. It really, really, does make sense to do it that way, it knows my habits and the drive and it's easy to calculate the best power mode for every part of the commute.

    My commute is definitely outside the EV range, but if I just use EV until depleted, I get bad gas mileage in comparison to if I start out in HV mode (it's the fastest part of my commute, the first 20 minutes) I know, I've tried, i get in the 70's if I start in EV, and in the 90's if I start in HV. If I'm even more careful about what mode I'm in when, I can break 100MPG. It most definitely matters!!
     
    john1701a likes this.
  2. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    12,749
    5,243
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Classic words uttered when a Prius owner achieves the next level of efficiency awareness.

    It's amazing how empowered we become upon discovery of how much those seemingly simple displays actually tell us.
     
    heiwa and Bob Comer like this.
  3. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    21,739
    11,327
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    All of which points to EV Auto not needing to exist.

    For what most were expecting of EV Auto, destination doesn't need to known by the car. Only the driver needs to know that they will be going beyond their EV range. They want lower thresholds to ICE use from EV Auto in order to extend the grid charged miles instead of manually switching between EV and HV. Yes, the motors are efficient at higher speeds, but they are still more efficiency at lower ones.

    As is by most reports, there is no difference between driving in EV and EV Auto, which has people questions why EV Auto is there. North America was not the primary market in mind while Toyota was designing the Prime. What the NA calls EV auto was likely programed then. The pure EV mode that NA gets was likely developed later, and EV Auto simply wasn't changed for the market.
     
    jaqueh and Bob Comer like this.
  4. Since2002

    Since2002 Senior Lurker

    Joined:
    Nov 12, 2011
    936
    1,097
    0
    Location:
    Duluth, GA
    Vehicle:
    2006 Prius
    Model:
    N/A
    It seems like EV Auto is being discussed by some people as an efficiency feature, when in fact it is supposed to be a power feature, at least according to the owner's manual:

    EV Auto.png

    Based on comments in this and other threads, as a general statement it sounds like HV is most efficient (i.e. let the computer run things). However it seems that owners are able to look at the bigger picture of their entire driving day and in many cases are better equipped to manage the use of the limited amount of EV range that is available between charges, by being able to switch to EV mode (or out of it) during certain segments of their route.

    However EV has a power limitation compared to combined electric and ICE. EV Auto is designed for owners who want to be able to drive in EV mode for some segments of their route but not sacrifice power when needed.

    Based on some of the comments it sounds like maybe EV Auto is not working like it should, either that or people are not pushing beyond what the electric motor is capable of.
     
  5. mdhare

    mdhare Member

    Joined:
    Feb 7, 2017
    58
    33
    0
    Location:
    Madison, WI
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    I wish EV auto was like HV without the forced regen (same ice/ev usage algorithm in terms of acceleration demand). I too do not use ev auto because it operates nearly identical to pure EV for my habits. Like many here I swap to hv as soon as i hit ~45 mph and know I can't do the whole run in EV. Sometimes I come home with charge precisely because I'm bad at estimating remaining distance at highway vs city speeds. Car claims to have 40+ miles on full charge but I know that is only at city speeds assuming lots of ideal variables.
     
  6. Flaming

    Flaming Active Member

    Joined:
    Aug 9, 2017
    138
    122
    0
    Location:
    QC , Canada
    Vehicle:
    2017 Prius Prime
    Model:
    Technology
    same situation here , EV = EV Auto .. the engine never start. I would like EV Auto mode to be programmable by the user .. i mean i would like to set HV mode when i go 75 Km/h or faster and pure EV at lower speed than 75 Km/h. This is what ''auto'' mode should be ... so i don't have to hit the HV button at all .
     
  7. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,018
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Like I keep saying, that's an illogical way to do it - speed based. This is because speed isn't the only thing that affects power demand. The other ones are acceleration and slope.

    For example, 45mph uses the same power as 25mph climbing a 2% slope or 73mph descending a 2% slope.
     
    heiwa likes this.
  8. OptimalPrime

    OptimalPrime Member

    Joined:
    Sep 17, 2017
    107
    74
    0
    Location:
    Keene/Nashua
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    That's a mode I'd also like, but I'm not sure I'd want to give up the current EV Auto mode to get it. I like the idea that absolutely flooring the pedal in EV Auto mode gives you the absolute maximum power the car can deliver, without the distraction of having to hit the EV/HV button button....just mash the gas pedal.

    What I'd REALLY like, is for the EV/HV button to be EVAuto/HV, and make EV-only the odd man out. Then put the EVAuto/HV button on the steering wheel, backlit to make it the easiest button to find/use all the time. Perhaps additionally rather than just moving it. Make both of them durable, and make them be the redundant backup for each other. You know how the finish gets worn off the garage-door button on your rear-view mirror? That's what I'd expect will happen to many people's HV/EV button in this car.

    The ability to set the car up to ask a couple of questions upon startup about where the next charge is expected, and getting there via what intermediate destinations/routes, would be nice. Something very simple, but with some available options for entering more detailed "trip to next charge" information, such as desired charge state at each intermediate destination including next charge location (e.g., if you won't have time to fully charge there), etc. Or just a choice of different well-chosen, well-named strategies for it to use, and/or miles to next charge.

    And maybe a "record my manual mode changes for this trip" capability, then save/name the strategy yourself. Such as "His winter morning commute via Dunkin", "Her summer evening commute via daycare", "Fastest route to beach house", "Hypermiling to beach house" etc.
     
    Lucifer likes this.
  9. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,018
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Even with a cold engine? I don't want the engine to fire up to full throttle when it's cold. Ever.

    I'd rather them get rid of EvAuto. It's the only one I haven't used and the only one I never intend to use because it's the only one that doesn't serve any useful purpose as far as I can tell.

    Why? I've used it so far only on one of my four long range trips. Otherwise, all Ev, all without pushing any of the buttons.
     
    heiwa and jaqueh like this.
  10. jaqueh

    jaqueh Active Member

    Joined:
    Jul 13, 2013
    341
    199
    0
    Location:
    San Francisco
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Agreed starting the engine in full throttle all of a sudden can’t be good for its longevity.
     
  11. Lucifer

    Lucifer Senior Member

    Joined:
    Aug 23, 2015
    1,014
    485
    0
    Location:
    Nh
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    I would gladly switch the steering wheel heater switch with the EV switch, if anyone has please enlighten.
    I live 1000’ above the daily drive, I use the switch constantly, the steering wheel heater switch is the best safety device ever, but I’m willing to lean over a bit to engage.
     
  12. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    12,749
    5,243
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Since the system doesn't do that, it's a moot point.

    Get an aftermarket gauge. Watch. Ordinary startup, even on a highway ramp, holds the engine to 1500 RPM.
     
    heiwa likes this.
  13. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    44,834
    16,072
    41
    Location:
    Canada
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    They need a small rotary knob on the steering wheel to change between EV, HV and EV Auto if people are actually using them often. (Similar to the knob on Ferraris for switching between snow, normal, sport, race and "all off" [trac, esp])
     
  14. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,018
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    99% of my drives don't involve touching those buttons at all.
    The other 1% including me touching Hv/Ev once or twice.
    I've never touched Ev Auto.

    The only reason I can think of to touch them frequently is "stacking".
     
  15. Bob Comer

    Bob Comer Active Member

    Joined:
    Sep 20, 2010
    708
    456
    0
    Location:
    South Carolina low country
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Or you have a longer commute with fast and slow parts. I hit the EV button twice a day...
     
  16. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,018
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I drove 58 miles each way Sunday. I hit Hv/Ev twice each way.
     
  17. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    12,749
    5,243
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    It stays in the EV default for my entire commute.

    The only time I switch it out is on long highway drives.
     
  18. Bob Comer

    Bob Comer Active Member

    Joined:
    Sep 20, 2010
    708
    456
    0
    Location:
    South Carolina low country
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I can only charge at home, otherwise I'd be doing the same, twice each way. My commute is a bit shorter than that, but nowhere near EV only, even one way.
     
  19. Bob Comer

    Bob Comer Active Member

    Joined:
    Sep 20, 2010
    708
    456
    0
    Location:
    South Carolina low country
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    It's pretty close to useless on a USA based car -- its basically just EV. I could use it instead of the EV button and it would end up being the same mileage.
     
  20. ct89

    ct89 Active Member

    Joined:
    Dec 31, 2010
    323
    266
    1
    Location:
    New England
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I haven't been able to demonstrate a cost benefit of switching between EV/HV for trips that I know will eventually deplete the battery but I will say that I enjoy driving in EV mode more when not on the highway and notice the difference less on the highway.

    From a driving experience point of view, I will spend the effort to reach down and switch to HV after getting on the highway even if I can't prove it results in better net mpg...I not saying it doesn't but just that it seems close and that I personally haven't been able to conclusively see a notable net efficiency difference...