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Driving in Charge Mode and mpg

Discussion in 'Prime Fuel Economy & EV Range' started by Robert21PrimeLTD, Aug 31, 2024.

  1. Robert21PrimeLTD

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    I charge my plug-in at home to a full charge and drive in ECO Mode. I go approx. 25 miles on the traction battery before the ICE turns on.

    My question is, if I switch the drive mode to CHARGE Mode so that the ICE charges the HV while driving will my overall mpg decrease? Logic says that it will. I don't drive enough miles to test it in a timely manner.

    Does anyone have experience with Charge Mode?

    [​IMG]
     
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  2. Louis19

    Louis19 Active Member

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    Charge mode will decrease your overall mpg , ICE will work harder accomplishing 2 tasks meanning propulsion of the car and charging the traction battery simultanously . Charge mode will not happen over 80% of traction battery charge level.If you need a quick charge to 80% , charge mode will get you there more rapidly
    than L1 or Level 2 charging ....
    I use it to burn aging old gas before it gets stale, mind you I use one tank per season.;)
    For my usage , when I need gas , I go for half a tank , unless I need to go for a long trip.
     
    #2 Louis19, Sep 1, 2024
    Last edited: Sep 1, 2024
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  3. Robert21PrimeLTD

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    Wow, one tank per season. I've been using 1 tank per 1,500 miles. I do like your 1/2 tank idea. Thanks for your insight.
     
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  4. bisco

    bisco cookie crumbler

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    It will certainly reduce mpgs, but idk if anyone has calculated it
     
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  5. The Tramp

    The Tramp Italian Prius Expert

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    I have.

    In Charge mode it "steals" 8kWh from the ICE. How much is that in MPG, well, it depends how fast or slow you go.

    But whatever the ICE produces, 8kWh will go to the battery.

    That is twice as much you can get from the Level 2 charging, and it stops at 80% so not to overheat the battery - we know how much Toyota babysits the car.
     
    #5 The Tramp, Sep 3, 2024
    Last edited: Sep 3, 2024
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  6. Louis19

    Louis19 Active Member

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    Hey thanks for your info. For @Robert21PrimeLTD living in Nashville USA , where gas price are very cheap by my standards (I live in Canada) ,it could be a GO for charge mode since 8KW/h will do the trick in less than an hour to acheive 80% of charge level(y)
    P.S it also depend of your electicity rate:rolleyes:
    It could be less mpg but less operating cost also
     
    #6 Louis19, Sep 3, 2024
    Last edited: Sep 3, 2024
  7. Robert21PrimeLTD

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    I currently pay a little less than 10 cent/kWh and calculate that it costs me about 68 cents to fully charge the HV from 0-100% as recorded on the dash graph (20-80%) and takes 90 minutes with a level 2 charger. Today's price of gas in my area averages around $3.29/gal. My trips are relatively flat and mostly less than 45 minutes. Not sure how i could calculate which way to go, ECO mode or Charge Mode? Either way I won't save much on electricity or gas. Just seems that charging at home is better for the environment.
     
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  8. The Tramp

    The Tramp Italian Prius Expert

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    Assuming 0-100 is 6.1 kWh, 0-80% is 4.88 kWh.
    At 8 Kwh, it takes 36 minutes.
    To charge 4.88 kWh with an ICE efficency of 40%, you need 12.2 Kwh worth of gas. According to an online calculator, that is 0.365 gallons of gas, @ $3.29 = $1.20.

    68 Cents to fully charge = 54 cents to charge 0-80%.

    There is the Maths, IMHO not worth Force charging. Esp[ecially me at $8 per gallon.
     
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  9. Robert21PrimeLTD

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    Now my head is spinning and I'm a retired engineer, lol. As I suspected, not worth me using the Charge Mode. Thanks for the data and math.
     
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  10. Louis19

    Louis19 Active Member

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    [QUOTE="

    There is the Maths, IMHO not worth Force charging. Esp[ecially me at $8 per gallon.[/QUOTE]
    Yes indeed , in my part of the world , gas prices range is $4.77 to a peak around 5.65 USD a gallon , so not worth Force charging see post no 2.