Charge Mode ONLY mpg

Discussion in 'Prime Main Forum (2017-2022)' started by Maple88, Mar 10, 2025 at 6:12 PM.

  1. Maple88

    Maple88 Junior Member

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    I looked and looked and cannot find a direct, non-technical answer to this.
    What is the average miles per gallon on a Prius Prime using Charge Mode (engine only) from a completely empty traction battery to full battery?
     
  2. vvillovv

    vvillovv Senior Member

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    That's because it's variable, depending on how or / and when it's used. Using a few extreme examples of the differences that can show up.

    Middle of winter below freezing temps switching on charge mode right after starting the car while driving up hill to enter the freeway at 80 mph into a 20 mph headwind (for whatever crazy reason(s) )

    Middle of summer temps around 80 F 20 mph tailwind at speeds around 40 mph with a steady decent and no stop signs or traffic lights.

    Another big variable is how long charge mode is left on. 10 minutes to give a few % EV range (which the Prime wouldn't do by itself after running out of EV range, unless sometimes when on a long decent, it might. )
    Or running out of EV range and switching on charge mode and leaving it on until the Prime reaches 80% SOC when the Prime shuts charge mode off automatically and switches the Prime back into EV mode.

    All these scenarios give different results, but all of them give lower than normal MPG.
     
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  3. Maple88

    Maple88 Junior Member

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    So how many miles per gallon?
    I can put it into continuous Charge Mode by holding the EV button for about 2 seconds. It will charge until the battery is fully charged, and then it will revert to EV.
     
  4. bisco

    bisco cookie crumbler

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  5. john1701a

    john1701a Prius Guru

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  6. notspam3

    notspam3 New Member

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    I'm in Canada with below freezing temps, snow on the roads and many hills. We went from a fill every 1.5 weeks on our old HEV Prius @ 5.5L/100km to a fill every 4 weeks this winter in our 2024 Prime XSE, new getting ~2.0L/100km = 105MPG. Our fuel economy has been improving in the warmer weather above freezing - no surprise!

    You can view other owner's reported fuel economy at the Fuelly website
    under /car/toyota/prius_prime/2024

    Your fuel economy will depend on how you drive and how far you drive each trip and between re-charge cycles. If all your trips are under 50km between charges you won't be re-fuelling very often.
     
  7. Maple88

    Maple88 Junior Member

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    I'm sorry. I only want the answer to my question.
    If you go to any new car dealership, the sticker on the window tells you the average miles per gallon, be it highway, city, or combined. I am asking for charge mode only mpg, engine only, no electric motor used. Please, I am not asking for any other information.
     
    #7 Maple88, Mar 11, 2025 at 5:17 PM
    Last edited: Mar 11, 2025 at 10:43 PM
  8. jfschultz

    jfschultz Active Member

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    I tried it in town to help burn off the full tank of E10 that the dealer provided and the readout was about 25 MPG. -- Gee I need to replace the picture of a 2013 Plug-In Prius that I no longer own.
     
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  9. john1701a

    john1701a Prius Guru

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    Huh? Is that just demo MPG you're talking about. The video above used E10 and got much better efficiency, despite also charging at the same time.
     
  10. BiomedO1

    BiomedO1 Senior Member

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    If all your looking for is the Monroney sticker - here you go.
    Window Sticker Lookup by VIN | National Motor Vehicle Database
     
  11. vvillovv

    vvillovv Senior Member

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    There is no Average MPG rating for charge mode.

    It depends on how, when, speed, hills or flat, temps at the time charge mode is used.

    Pick a number, any number between 2 gallons per hour if using charge mode in your driveway while in Park -
    to 10 - 15 MPG less than what what the gauges in your car show the way you
    Normally drive the car.
     
  12. Maple88

    Maple88 Junior Member

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    Every car is subject to variable driving conditions, yet an average mpg is a figure that is printed on its new car sticker. If a Prius only had the gas engine that it came with, what would be the average mpg?
     
  13. vvillovv

    vvillovv Senior Member

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    There is no average MPG for charge mode.
    If you want one pick one yourself or complain to the EPA for not putting on on the Primes new car sticker.
     
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  14. Maple88

    Maple88 Junior Member

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    I am only asking for others knowledge and experience for an estimate on the question that I posed.
     
  15. vvillovv

    vvillovv Senior Member

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  16. MAX2

    MAX2 Active Member

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    How do you expect to charge the high voltage battery using only the engine without using the electric motors?
     
  17. Nick r24

    Nick r24 Junior Member

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    Charge mode means thr engine is always going to run. I would assume the fuel economy would repuclate a corola at that point.
     
  18. Trollbait

    Trollbait It's a D&D thing

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    Those numbers are from EPA testing that is a mix of different speeds. No one has the the Prius PHV through the tests while charge mode.

    As for owners testing it, well you'll need to also know the speed and other conditions, as the mpg will change with those. Then what is reported is most likely coming from the dash display that can be optimistic.

    Zero, as it can't move without the electric motors.