Best mode for long upgrades

Discussion in 'Clarity' started by neal adkins, Oct 17, 2019.

  1. David Towle

    David Towle Active Member

    Wow I didn't realize that. That makes no sense for efficiency! (And if true adds evidence to debunk Insightman's engineering optimization theory) But its one factor that helps explain why my winter gas mpg is so much worse than summer. I averaged about 36 last winter, versus a pretty consistent 50 over the summer in similar conditions.

    Not only would electric heat use up more charge, but it also has to drive the generator harder, which results in less time it can go into efficient gear mode. Of course friction and higher drag snow tires are part of this too. But this all adds up as there were times in winter when the car would not go into gear mode at all on the highway.

    My 3 series BMW that the Clarity replaced would typically go from 30 mpg in the summer to 27 in the winter, a tiny range in comparison, but of course that car is a lot lower on the efficiency scale.
     
  2. skylines

    skylines New Member

    It has been somewhat amusing to see the number of threads and complaints on this group about the engine coming on for short periods when the battery is fully or mostly charged. I can just imagine the outrage if the ICE was on continuously to provide heat to the cabin.
     
    insightman likes this.
  3. David Towle

    David Towle Active Member

    Yeah I drive the car completely different from most on this list, only plugging it in once a month to exercise the full range of the battery. So different priorities.
     
  4. skylines

    skylines New Member

    Okay. It isn't the perfect fit for your particular usage. Which clearly isn't the norm as you admit. There just no way to satisfy everyone's edge use cases. Not saying there is anything wrong in your preferences and complaints at all of course. It is just amusing to see both ends of the complaints in the same place.
     
  5. neal adkins

    neal adkins Active Member

    One member has it right in saying he wished he would have went all in on an ev. No ice to complain about. But i like the idea of about 90 percent of my driving days being 90 percent electric. The purpose of this thread was to help those who get rattled by the Claritys performance in long climbs, and, how to use ice/ev in an intelligent way. Many champion how little or almost no ice usage. I think this can be a snare resulting in decreased longevity of the ev battery especially in situations that put a heavy, rapid draw on the ev battery for an extended time. Of course imho.
     
    Clarity_Newbie likes this.
  6. Walt R

    Walt R Active Member

    This aspect of PHEVs is something that I didn't know about before buying the Clarity, and I am so glad that the Clarity can provide heat in EV mode. I expect I would have been quite disappointed if I had bought a Sonata or another mild-PHEV which would run the ICE all winter (or I would be refusing to turn on the HVAC). This is the main reason I now consider there to be two sub-types of PHEV - those intended to run in EV whenever there is battery, and those intended to run ICE most of the time and have the battery "help". I think only the Volt, Clarity, and maybe Pacifica may be in the first group.

    The Clarity has made me a big fan of the serial hybrid (or, more sexy to call it a locomotive-type powertrain). I hope that we see additional heavy-duty usage which can't operate on battery-only adopting this approach. To me, eliminating the multi-gear transmission and getting the immense torque of an electric motor are wins for heavy-load applications.

    I was never in real danger of getting a mild-PHEV though, as my shopping criteria was adequate EV range for my commute, which meant minimum 40 miles for PHEV, or more for EV to have safety margin.
     
    TomL likes this.
  7. HagerHedgie

    HagerHedgie Member

    The clarity also made me a fan of the serial hybrid especially with the addition of the direct drive gear.
    I’m still sold on the Prius style planetary gear set for non plugin hybrids.


    Sent from my iPhone using Inside EVs
     
  8. neal adkins

    neal adkins Active Member

    I have had my clarity for about 15 months. I still have a since of amazment with the car overall and think its alot of car for the money. I had my 2nd oil change at about 12k miles. The dealer recommended to change the air filter but i thought since the ice doesn't run alot i would check it myself first. Turns out it still looked brand new. I probably have around 5k miles on the ice.
     
    TomL likes this.
  9. David Towle

    David Towle Active Member

    I assume this means you understand how the Prius system works? My assumption has been its very similar to the Clarity, except there is a 2 speed transmission so the engine can power the wheels directly at a much lower speed than with the Clarity's 1 speed transmission. Is this correct?
     
  10. David Towle

    David Towle Active Member

    Another good example of how differently the Clarity can be used. While you would refuse to use heat to avoid the ICE, I have never used the heat in EV (I live in CT) because I hate to waste the kw. Whenever I'm driving more than about 5 miles I always put it in HV or HV charge so I get the "free" waste heat from the engine. I am annoyed at learning here that in HV it still uses electric heat on top of the ICE heat. To me in EV it should be using all electric heat, and in HV or HV charge it should be all engine heat. If the passenger compartment temp drops a little low from not enough engine heat it should be just allowed to do so.

    BTW I absolutely love this car, just passed my one year anniversary a few days ago. Almost 25,000 miles of enjoyable driving. Not cheap to maintain though, got a crack in the windshield that got fixed this week, total bill to the insurance company was almost $2100 (OEM windshield). Wish I could get a Honda warranty for longer than the 120,000 miles I got.
     
  11. insightman

    insightman Well-Known Member

    Management on Tuesday: "Engineers, did you finish replacing that fuel cell with an engine?"
    Engineering on Tuesday: "Yes, sir."
    Management on Tuesday: "Did you finish reducing that 22.5 kWh battery to 17 kWh?"
    Engineering on Tuesday: "No, sir, we'll try to get that done tomorrow."
    Management on Wednesday: "Engineers, did you finish cutting down that battery?"
    Engineering on Wednesday: "Yes sir, we just have to fine-tune the ECU for maximum efficiency."
    Management on Wednesday: "No. You're done. Ship it."
     
  12. Kerbe

    Kerbe Active Member

    Actually Prius and Clarity are very, very different: Prius is a parallel hybrid - an ICE-powered vehicle with an electric motor in the transmission. The only real difference between a standard Prius hybrid and a Prius Prime PHEV is the size of the battery. All Prius models use a planetary gear-based variation on a CVT - so there's no shifting even though there are gears. Clarity is a serial hybrid - an electric motor-powered vehicle with an ICE generator that can, in rare situations, add torque to the drivetrain: The ICE in a Clarity never works on its own to power the vehicle - it works only in conjunction with the electric motors. The second electric motor/generator in the Clarity simulates a transmission which is why Honda refers to it as an "eCVT" - "Electronic Continuously Variable Transmission". Hope this info clarifies the situation!
     
    TomL likes this.
  13. HagerHedgie

    HagerHedgie Member


    https://auto.howstuffworks.com/hybrid-car7.htm

    Check out that link. I remember seeing another website a few years ago with a moving diagram that shows how each gear moves in relation to the other, but I couldn’t find it.
    Toyota and Honda approach the challenge completely differently. IMO Honda is very similar to ships, heavy equipment and locomotives that have a engine-generator making power for a drive motor. Honda also adds a rather large battery that may be charged externally. And the direct drive gear. This works great when the electric motor can handle all the power needs of the car. It also allows relatively efficient use of gas at higher speeds.
    Toyota uses a clever system of planetary gears with two motor/generators and an ice linked together. One m/g has a fixed ratio to the drive shaft. The other, smaller m/g unit allows the drive ratio from the ICE to be adjusted by changing its speed and direction of motion. It’s a very clever CVT with no pulleys, torque converters or clutches. Its also simple, efficient and robust.
    My ‘13 Prius gets 45mph at a steady 80mph. It also revs up very smoothly and I don’t feel any anxiety flooring it repeatedly on the highway. 160k miles so far.
    Clarity is a dream with EV mode, especially around town. I feel bad for everybody else I see driving around in a German luxury sedan and that’s before I remember that I only paid half as much!


    Sent from my iPhone using Inside EVs
     
    TomL likes this.
  14. ClarityBill

    ClarityBill Active Member

    Just remember, even my statements are just some unknown guy on the internet... Your winter efficiency is similar to my experience, and that is how I 'determined' the resistance heater runs in HV mode: I could be wrong.

    I also tried reducing the heating load, and it seemed to increase my winter mpg dramatically. (I used recirculated air rather than fresh air for a winter highway trip.)
     
  15. David Towle

    David Towle Active Member

    Thanks for clarifying Unknown Internet Guy! (ever consider changing your list name to that?)

    I'll try the same experiments but of course that doesn't work in a lot of conditions without fogging the windows.

    Recirc buttons are one of the great annoyances of modern cars to me, I remember even a bottom of the line 1982 Datsun Sentra I bought new had a control so you could continuously adjust from 0% to 100% recirc and anywhere in between. So much better. Although you really did need it in that car since lots of heat was required with all the bare metal in the interior.
     
  16. ClarityBill

    ClarityBill Active Member

    I believe modern cars are required to have some fresh air at all times (never 100% recirc)... The tightness of modern cars could build CO2 levels and harm occupants, if no fresh air is brought in by the HVAC system. Therefore, pressing the recirc button would not shut off all fresh air.
     
  17. David Towle

    David Towle Active Member

    It does shut off the outside air enough to fog the windows under many conditions. I would be fine with adjustable recirc limited to 80% max or whatever is safe, as long as its adjustable.
     

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