Why I Hate my Prius Prime

Discussion in 'Prime Main Forum (2017-Current)' started by stevepea, Apr 29, 2017.

  1. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    14,787
    6,595
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    Don't forget, a portion of the engine's torque output is always going to MG to make electricity while running, and some of that goes into the battery.
     
  2. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,924
    3,554
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    It doesn't have to. It can be going into MG2 to propel the car. In fact, battery power can even add to that.
     
  3. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    14,787
    6,595
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    Of course it could. Just saying the electricity for engine off driving in hybrid mode doesn't all come regen braking. Some does come directly from the engine, and it all comes from gasoline burned. Which is EV% display on a hybrid dash is mostly for bragging rights, and using the one from the gen4 is useless info on the Prime.
     
    bisco likes this.
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    86,293
    38,192
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
  5. stevepea

    stevepea Senior Member

    Joined:
    Apr 16, 2017
    511
    554
    0
    Location:
    California
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    I know this thread has gone off onto a few different tangents, but in case someone missed my question earlier, I'm wondering if anyone has the answer for this (as I do know someone who has the original PiP and has never once charged his car):

    (2)
    : Regarding battery longevity, if one drives almost all freeways, and were to never use anything but the HV mode (never plug in his car and never use the all-EV mode): Over the long run, is it better to (a) not ever plug in, and have the car keep the battery just at around the lower 20% HV buffer level, or (b) to have plugged it in once three months ago, and have the car keep the battery around the 90% level?

    Thanks!
     
  6. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,924
    3,554
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Better between 20% and 50% than 90%.
     
    fuzzy1 likes this.
  7. stevepea

    stevepea Senior Member

    Joined:
    Apr 16, 2017
    511
    554
    0
    Location:
    California
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Thanks, that's what I figured...
     
  8. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    14,787
    6,595
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    Keep in mind that there is buffer capacity kept above and below what the Prime and PiP uses. So the 20% used in hybrid mode could be closer to 30% from the battery's perspective.
     
  9. Ed From Syracuse

    Ed From Syracuse Junior Member

    Joined:
    Apr 4, 2017
    28
    35
    0
    Location:
    Syracuse
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    That is some mileage there! When I first got my Prius it was only charging 23 miles. Now when I charge it at home it's about 32.4. Now that spring is here I can travel to work and back home and have 5.6 miles left. In winter time I will have about 7 miles when I arrive at work left because I use the heater. I haven't used the AC yet but I'll keep you guys posted.
     
  10. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,001
    1,166
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Great thoughts! Thanks.

    I'm guessing that you might the P.Prime most usable just as ... "more of a Prius." Here's what I mean that: One of the main historical goals of the Prius design has been to make sure that the ICE only runs when it can do so at optimal efficiency, which is typically (maybe not strictly, but typically) sustained, medium-to-high-speed driving.

    So, with a 60-mile commute, you might do well to take a strategy like, "switch to hybrid mode when you expect to be driving above 50MPH for a while" and EV otherwise, or for-sure EV when you expect to be driving at low speeds or stop&go for a while.

    FWIW, the two main things that deter me from getting a Bolt are, first, its lack of auto emergency braking and radar-adaptive cruise control (DRCC), and second, the fact that the main places I expect to take long road trips to have about 3 times as many Tesla connections as anything the Bolt can connect to.

    Admittedly, I probably am going a little overboard regarding ADAS functions, since I'm a very cautious driver anyway, and haven't had an accident of any significance in ~40 years of driving. For me, TSSP is to improve the confidence and relaxation of my commute more than to make it greatly safer. I just want to know that TSSP can improve my awareness and "has my back" if I were to make a mistake!


    iPhone ? Pro
     
  11. Witness

    Witness Active Member

    Joined:
    May 6, 2013
    112
    115
    0
    Location:
    San Francisco Bay Area
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    I have the old Prius Plug-In. Would love a Prime. The complaint about the EV mileage isn't a thing, in my opinion.

    I drive at minimum 110mi every weekday to get to work. Sometimes I'm driving up to 140mi, depending on where I need to be during the day. I only have about 11mi of EV to work with and I average about 60mpg using a combination of EV and Hybrid.

    If I were you, I wouldn't really be using EV on the freeway, or not much. The way I do it is run EV for about 2.5mi to get to the freeway then switch to HV. I get to the final 5mi stretch of the freeway where I can run EV in moderate traffic and get away with only using about 2.5mi of EV. At lunch, I may run out to grab some food or run an errand - all EV. Leaving the office, I'm running EV for about 1.5mi to get to the freeway where I'll switch to HV. On the ride back, I charge stack and can accumulate up to about 3.5mi EV charge. As soon as I get off the freeway, back to EV to pick up kid and drop off to a class, then roll back home with barely any charge left. A short charge later, I go pick up my kid with just enough to make the round trip.

    That's how I do it with my limited range. It's a hacking game to me with a lot of strategy to maximize mpg. When I need to switch to HV and the ICE starts to warm, I want to be moving instead of idling and burning fuel. This helps the mpg average. I save my EV for short trips during the day, because warming up the ICE is where I waste the most fuel. I didn't finish more than a 1/4 of your post, but to me it looks like you're still learning how to take advantage of the Prime. I can't go EV until it has a 200mi battery and even then, I take 1000mi round trips with the family several times a year and the PiP has been great for it.
     
    bwilson4web likes this.
  12. stevepea

    stevepea Senior Member

    Joined:
    Apr 16, 2017
    511
    554
    0
    Location:
    California
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Thanks everyone, for your responses. I think that's what I'll most likely be doing: using EV on streets (small percentage of driving) and HV on freeway. The car does seem to be quite good at MPG (and switching back-and-forth between EV and ICE even in HV mode if you're driving flat and even speeds). One more note about the Bolt mr88cet, is that it's also missing Navi.
     
  13. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,001
    1,166
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Just a couple (further) thoughts on your thoughts:

    First, I don't see anything bad about crafting the would-be fast-charge half of the charge port into a cap holder. If it were left to dangle, it could scratch the paint.

    Second, the reason Toyota make the P.Prime strictly a four-seater almost certainly is weight. By categorically precluding five people, they don't have to engineer the car -- the suspension, resulting fuel economy numbers, etc. -- for the weight of a fifth person as well as the battery and cargo weight.


    iPhone ? Pro
     
    Tideland Prius likes this.
  14. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,001
    1,166
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Good point! The counterpoint, however, is that the Bolt does support Apple CarPlay and Android Auto, which gives you NAV and many other features.


    iPhone ? Pro

    The other thing, however, is that part of the reason why we're getting the P.Prime, and not trading in our 2009 Prius, is that my wife is working on getting her driver's license, meaning that we'll need two cars anyway. (Actually the hardest part is studying up for her learner's permit in English, since we mostly speak Mandarin at home!)

    Buuuuut, having TSSP to help me teach her to drive has a couple of advantages: First, it will be very thorough; it will let her know when she makes a wide variety of basic-driving mistakes. Second, it won't be **me** complaining to her! If I try to point out every mistake that TSSP can point out for me, it might strain our marriage!


    iPhone ? Pro
     
    #74 mr88cet, May 4, 2017
    Last edited by a moderator: May 5, 2017
    jmarkd7 and Trollbait like this.
  15. Since2002

    Since2002 Senior Lurker

    Joined:
    Nov 12, 2011
    936
    1,091
    0
    Location:
    Duluth, GA
    Vehicle:
    2006 Prius
    Model:
    N/A
    I was thinking that to squeak out the maximum efficiency you would always want to arrive home with absolutely no remaining EV charge, in order to maximize the amount of grid power that you are able to put into the car. Even though this means ICE will come on for the last mile or so, it would already be warmed up since you just got off the freeway.

    Unless you need that bit of charge left over because you don't have quite enough time to charge up for your final chauffeur run of the day?
     
  16. Since2002

    Since2002 Senior Lurker

    Joined:
    Nov 12, 2011
    936
    1,091
    0
    Location:
    Duluth, GA
    Vehicle:
    2006 Prius
    Model:
    N/A
    Recycling somewhat a post that I made a few months ago - the system should be able keep track of how much electricity is coming from grid charging, how much comes from regen, and how much from ICE. Then for calculation purposes it could just assume that the electricity consumed first is the electricity that came from grid charging. Then once that "pool" of electricity is used up then it would assume that electricity consumed after that is from regen, and once that is used up any additional electricity consumed would be attributed to ICE. Then after a say 100 mile trip the display could show you that the power consumed during those 100 miles came from:

    X kWh of plug charging
    Y kWh of regenerative braking
    Z kWh of regenerative coasting
    Z1 gallons of gasoline

    HV battery charging as well as charge mode would be accounted for in the gasoline column. Any unused grid or regenerative electricity left over after the trip would be carried over to the next trip.

    I realize this has limits in terms of accuracy, but at least it would give you some ballpark idea of what is going on in terms of power consumption. And I suppose it could be argued that regen electricity actually comes from gasoline, true but since in most cars that energy is lost, in this case it would be considered "found" energy.
     
  17. Witness

    Witness Active Member

    Joined:
    May 6, 2013
    112
    115
    0
    Location:
    San Francisco Bay Area
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    On the freeway, it's ICE. Running EV at highway speeds is just not efficient on a per mile basis. On the street is where I use EV and I know how much I'll need to get home. So, I wouldn't be using EV on the freeway except for entry and maybe exit. The problem with running EV to zero and letting the engine run for the last mile or so (with stop lights) is that it'll make the trip's mpg even worse. If I hit a red light, the engine would still run to charge the battery back to a minimum level. So, best to ensure the engine doesn't come back on - it's better continue running the engine until you have enough EV power to take you the rest of the way home.
     
  18. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,924
    3,554
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Running Ev on the highway is just fine if you have enough range to get where you're going without the engine starting.
     
    joachimz likes this.
  19. mr88cet

    mr88cet Senior Member

    Joined:
    Sep 9, 2008
    2,001
    1,166
    0
    Location:
    Austin, TX
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Yes, I definitely agree. A lot of my ~19-mile commute is bumper-to-bumper, but the last part of it usually gets up to highway speeds for a short time. I'm sure as heck still going to do it all in EV mode, since it's a known 19-mile journey with a charger at the end of the "rainbow."

    But for quasi-indefinite distances, or at least >25 or so miles, better bet to do HV on those long highway-speed portions.


    iPhone ? Pro
     
  20. Since2002

    Since2002 Senior Lurker

    Joined:
    Nov 12, 2011
    936
    1,091
    0
    Location:
    Duluth, GA
    Vehicle:
    2006 Prius
    Model:
    N/A
    Why would it do that? I assumed that HV mode in the Prime is like HV in a regular Prius, it doesn't run ICE when you are stopped unless the HV battery happens to be really low. So I would think that even if the EV "segment" of the Prime's traction battery is depleted, as long as the HV "segment" has a normal amount of charge it won't run ICE while you are stopped. And even if it does need to start ICE to charge the HV segment of the battery, that shouldn't reduce the amount of grid charging that you will be able to do when you get home. I realize it's just a mile, but a mile a day adds up, 300+ miles a year that you could be charging from the grid but instead are using gasoline.

    Or maybe it doesn't make that much difference, I don't know since I am currently "Primeless" (one level above clueless). I have just been under the impression that the simplest way to maximize grid use is to always try and deplete EV charge on each trip.
     
Loading...