Going gas

Discussion in 'Clarity' started by Ken7, Oct 29, 2019.

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  1. As shown in the above spreadsheet, I think we average about 42 mpg on the highway. Probably a tad more in town.
     
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  3. fotomoto

    fotomoto Active Member

    As a former, early Gen1 volt owner I can say the misconception was initially perpetuated by GM. Eventually they released some engineering animation videos that demonstrated the ICE assist. Quicker 0-60 mph times in hybrid mode confirmed.

    Disagree. The PHEV, as the acronym implies, is basically a plug & charger added to a hybrid drivetrain; a technology that is increasing in availability across the industry and will be around for a long time. Start/stop tech (a very mild form of hybrid) is now just about available on everything even trucks. Just like BEV tech, it takes butts-in-seats to demonstrate the advantages of PHEV over traditional ICE and that can only come with more available models.

    Cheap batteries that can charge quickly with little to no long term affects (solid state most likely) along with economical and widespread public charging will make PHEV tech obsolete. None of that is remotely close to happening in the USA nor the world right now. My guess? Another 15-20 years. PHEV tech doesn't need to wait nor rely on the rollout of massive infrastructure, it's already in place (chicken and the egg).

    IMO.
     
    Last edited: Oct 31, 2019
  4. KentuckyKen

    KentuckyKen Well-Known Member

    AFAIK from posts of data here and some Google-Fu, the efficiency of the onboard charger may best be estimated at 92% (ranges run from 86 to 94% depending on the source). The EVSE is just an intelligent switch that directs the power to the charger per its commands. Also Level 2 EVSEs are a little more efficient in the charging process than Level 1s are.

    Don’t worry about what’s coming from the wall (what you’re paying for) vs. what actually gets into the battery (what you get to use). You’re paying for what your EVSE app or external device like a Killawatt records and that’s what you’re calculating MPGe, kWh/100 miles, miles/kWh, etc. with.
    Just like when you calculate mpg in a gasmobile, you don’t try to subtract out all the taxes from the price per gallon. You calculate with total cost for what ends up in the tank.
    Gas cost is straight forward, but it does get a little tricky with the electricity cost, since there may be different rate schedules to contend with like TOD, Tiers, and base charges.

    Hopefully @MrFixit will post more data on how he calculated the slope on his very helpful and much appreciated graph.

    As a foot note, posts here seem to indicate about a maximum of 14.4 kWhs to charge a fully depleted battery, but that is if course temperature (mostly) and battery health dependent. Taking 14.4 kWhs from the EVSE and adjusting for an estimated 92% on board charging system efficiency, one gets ~13.2 kWhs entering the battery that is actually usable. For our 17 kWh battery that is about 78% usable capacity giving about a 22% buffer for battery protection and longevity that is split in some ratio between top and bottom of SOC. (My feeling is that these figures are probably +/- 10% but do have close agreement with other calculations so they’re in the ballpark)
    This is a very good feature of the BMS (Battery Management Software) as repeatedly charging to full capacity and discharging to completely empty will destroy a Li-ion battery.

    And yes, I routinely get an honest 49 mpg on HV on the few HV trips I have taken. You just have to remember that driving styles (lead foot, higher speeds, aggressive driving, etc.) and conditions (# of passengers, weight of luggage, heater/defroster [big drain] or AC [less drain] usage), can have a large impact on MPG, MPGe and efficiencies, as will external conditions like rain, night, wind, and elevation changes. All these factors cause varying amounts of charge to be used to go the same distance.
    So don’t beat yourself up over not getting the same rosy results of some post here unless you can verify their conditions were the same as yours, that they are reporting round trip results, and are accounting for any charge depleted while in HV. You must compare apples to apples and sometimes that is not fully done on our forum.
    In my location and experience, my Clarity is 4 to 5 times cheaper in EV than any of my former gas-mobiles. And even if electricity was a little (not a lot, my wallet is only so fat) more per mile that gas, I’d still drive in EV for the comfort and the environment.
     
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  5. Robert_Alabama

    Robert_Alabama Well-Known Member

    I took @coutinpe 's post to be poking at GM for killing the Volt, not for the Volt's lack of an ability to pick between gas and electricity. Even with the Volts prior to 2013, it was pretty easy to burn gas when you wanted to and to burn electricity when you wanted to. The "Mountain" mode was much like HV charge in that it held about 40% of the battery in reserve and burned gasoline. If you never charged the early Volts and left Mountain mode on, you only burned gas as an overall energy source. On the flipside, if you left it in normal or sport mode and plugged in every 40 miles or so, you used 100% electricity.
     
  6. MrFixit

    MrFixit Well-Known Member

    @Mark W - The basis for my chart is shown on the annotations. The chart can be easily generated knowing the kWh/100mi, and the MPG. I simply used the EPA numbers for the Clarity (31 kWh/100mi, and 45 mpg).

    BTW - I believe the EPA number is based on the power into the vehicle (not on how much actually reaches the battery). To me, the car is a black box ,and you pay for what goes into the charging port. So, the way the EPA does it seems perfectly correct.

    Is this exact? - Of course not. Driving style, seasonal temperatures, terrain, speed, etc. will all affect this.

    BUT I keep meticulous records of both electric input (wall power into the vehicle as measured by my Level 2 JuiceBox), and of gasoline input. I have found that this 'simple' assumption seems to be remarkably close for my circumstances. I would guess it is within a few percent.

    I feel like some people get hung up trying to get the 'right' answer, to the point of analysis paralysis. In this case, you will never have a precise answer (nor do you need one) if your goal is to compare the cost of gas vs. electric. I believe this rather simple 'approximation' is actually surprisingly good. Further attempts to be 'more accurate' seem futile because the variables outweigh the precision of any 'equation' you might come up with.

    Engineers (myself included) can easily get mired in too many details that are unimportant !! There are a lot of engineers and technical people on this forum, and that can be both good and bad !!
     
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  8. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    That's a very bad idea. It's of no help at all for battery health or life. Some claim it's necessary in a BEV to recalibrate the BMS (Battery Management System) occasionally by running the battery pack down to near 0% battery charge, and then up to 100%; but you can't do that with a PHEV because it will just kick in the gas motor when the pack gets down to around 30% charge or so.

    Even those who are well-informed on the subject and claim the discharge-to-near-zero-and-charge-to-100% cycling is occasionally necessary, only claim that you need to do it every 3 months or so. Claiming you should do it several times a month would be just putting unnecessary wear-and-tear on the battery cells.

    * * * * *

    The InsideEVs article below (and the discussion in comments following) discuss this issue as it relates to Tesla BEVs, which isn't all that relevant to the issue as it relates (or doesn't) to PHEVs, but at least it has discussion of the issue:

    "Does Battery Calibration Actually Recover Lost Range In A Tesla?"
     
    Last edited: Oct 31, 2019
  9. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    Yeah, GM did a lot of deliberate deception in how they originally described the operation of the Gen1 Voltec powertrain. They even claimed, before they actually started selling the car, that it was a pure serial hybrid, which indicated there was no direct engagement of the ICE in the powertrain!

    Later, some GM spokesman actually claimed that they did that only to protect their patents. I think that's B.S.; how would deceiving the public, telling them that a combined hybrid is actually a pure serial hybrid, help at all with legal patent rights? I've never seen anything I regard as a convincing explanation for why GM was so deceptive about that, for so long.

    I'm glad that GM finally issued an animation video showing how the powertrain was configured in its various operating modes. Until I saw that, I had no idea of how it actually works. It's much too complex to figure out how it works just by examining it carefully, as those of us with good mechanical aptitude used to be able to do with ICE powertrains, back before they started putting all those electronics into them.

     
  10. Under normal operation we cannot charge the batteries to 100% or discharge them to 0%. We can run down to EV zero and charge until the charger turns off. That’s not 0-100.

    I have yet to see anyone publish the charging protocol/BMS that Honda uses for the Clarity. We do know that 4.1v is a target voltage for each cell, 4.2-4.3v is considered to be 100%. 3v is the lower limit for a cell and I believe Honda has set a cutoff around 3.4-3.5v. Cell balancing is most likely built into the BMS. We just don’t know when it occurs.

    I doubt we can harm the batteries without going out of our way to do so. I regularly charge until full and run on EV to 10 miles or less. Some charge to 85% and turn off EV at 50%. I believe the BMS is capable of dealing with either practice. I choose to use the battery capacity that I paid for. If they die in 8 years Honda will give me new ones. If not, I’ll repurpose them for solar storage and part the car out.
     
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  11. Danks

    Danks Active Member

    Yes. People are getting 45 mpg in HV mode in the real world - at least in the summer. We've had 12 HV trips with fill ups. We've ranged from a low of 43 mpg to a high of 50. Only 2 were less that 45 mpg.
     
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  13. MPower

    MPower Well-Known Member

    My experience with long trips is that HV will maintain your nearly full SOC indefinitely. The biggest cause of the reduction is driver @KentuckyKen's head smacking failure to turn on HV again after stopping for gas.

    Also, if you turn off HV and turn it on again when the SOC is lower before it has recovered to the previous set point, the new lower SOC will become the new set point and as you can see from @Fast Eddie B'S trip chart over a long trip this slowly eats away at the SOC.
     
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  14. neal adkins

    neal adkins Active Member

    I didn't say that its nessacary to go down to zero or even 30 percent, although i dont think its disadvantageous to do so. But the clarity manual reccomends charging to 100 % before each drive. I do agree this may not apply to a Tesla.
     
  15. neal adkins

    neal adkins Active Member

    It depends. If you drive on a freeway (in hv) with little regenerative breaking it would be different than in town. If i drive on an upgrade (in hv) i loose battery faster. So i would say on flat road you would engauge direct gear drive and use little or no battery. Heater/ a/c usage comes into play as well. If i used only hv this time of the year i think it would take 3 or more tanks of fuel before i got down to 2 bars if starting at a full charge. But I have not tested this.
     
  16. coutinpe

    coutinpe Active Member

    Maybe we are not talking about the same stuff. I was referring to GM discontinuing the Volt and now even the Malibu Hybrid. Unsure how is that handling 'it' much better. On my end I would have preferred to buy an American PHEV but the choices were taken from me.
     
  17. M.M.

    M.M. Active Member

    It's funny, the tank is small but thanks to the high efficiency I didn't really have any problem with the gasoline range when on road trips. I went from Northern CA to Death Valley, and all over the place in the valley, without the tank size bothering me. In terms of miles of range, it's not that much different than the old Acura TL I had a few years ago, especially if I hang on to half the battery to use as a backup if I screw up and do run out of gas.

    No kidding on the financial part being geographic, though--right now my winter off-peak rate is $0.14/kWh (if I didn't have PV and had to buy electricity) and I'd pay about $4.50/gallon of gas if I ever bought any. On the other hand, I don't have a Clarity for financial reasons so I would use electricity even if it were the other way around.
     
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  18. Ditto on our road trips - we’re more than ready to get out and stretch and get a snack after three hours or so.

    I have to remind myself that electricity isn’t free. We’re spending about 80% of our time in our new TN home and charging nearly daily. Our electric bill last month was about $100, but I have nothing to compare it to, since we’ve never had a bill without Clarity charging involved. (As an aside, with overnight temps in the 30’s in E TN, our EV range just took a big hit, back to 39 miles yesterday and 36 this morning, down from around 50 all summer/spring).

    We filled up yesterday for $2.05/gal with our Weigel’s club discount. I think our electric rate is about .015/kwh, so no real financial impetus to run all electric, though we still try to do so as much as possible. We have a 200 mile round trip we make regularly, so we need gas pretty regularly as well. As such, the Clarity is a perfect “transitional” vehicle for us until pure EV ranges go up a bit more.
     
  19. Got it. I was a happy Volt owner for six years but a red light runner totaled it in late July. Picked up a used LEAF for a song and am waiting to see if Honda will even make a Clarity available outside of California for 2020. Honda may be taking this away from us as well, for much the same reason as GM--the need for a sustainable profit.
     
  20. insightman

    insightman Well-Known Member Subscriber

    I assume there will be no reductions from MSRP for 2020 Clarity PHEV's special-ordered from non-California states. My question is, did Honda actually set the car's MSRP high enough to produce a sustainable profit? Or, as with the gen-1 Insight, did Honda forego profit to obtain real-world data from a limited-production car?
     
  21. David Towle

    David Towle Well-Known Member

    I would be happy to pay a little more too, but from all I read "until gas prices go up" is going to be a very long way off. Lots of new oil coming on the market from new sources is likely to bring prices down in coming years and keep the oil economy going far longer than it should. Unless governments grow a set and start taxing oil the way it should be.
     
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  22. Groves Cooke

    Groves Cooke Active Member

    I got 47 mpg (real world, miles / gas pump gal) on an 800 mile road trip recently. Top speed mph on interstate type roads, not many hills. AC was on auto.
     
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  23. Not necessarily. It would depend on the EV range per charge.

    If EV range is 35 miles, cost per mile at $2.08 will be $.059.

    If a gallon of gas costs $2.40 and gives 48mpg, cost per mile will be $.05.
     

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