Question-2025 Prius in EV Mode: Reply quickly!

Discussion in 'Gen 5 Prius Technical Discussion' started by iRun26.2, Jun 13, 2025 at 6:28 PM.

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  1. Gokhan

    Gokhan Senior Member

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    That (4.4 mi/kWh) is actually dismal, let alone impressive.

    I routinely average around 6.5 mi/kWh in the city with my 2021 Prius Prime Limited. I can average 6.3 mi/kWh on the highway if I keep the speed at 55 mph or below. My record in the city was 8.1 mi/kWh (round trip, 25 mph).
     
  2. iRun26.2

    iRun26.2 Active Member

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    I have the most advanced models and it is rated as having less range than the cheaper models. Probably the more expensive models are both heavier and more wasteful of electricity because of the added functions.

    In any case, if I can get 4 miles / kWh , that still amounts to greater than 40 miles EV, correct? I find it confusing when the battery capacity is stated like 13.8 kW-hr yet the battery is claimed only used down to 25% (how many real kW-hr do we really get)?

    I am greatly looking forward to driving to work on Wednesday. This will give me a good idea of what time I can expect in the intended use for EV
     
  3. Gokhan

    Gokhan Senior Member

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    The EPA formula is:

    Useable BEV battery capacity at the 240-V plug (kWh) = 33.705 kWh/ge × BEV range (mi) / mpge
    Useable BEV battery capacity at the battery output (kWh) = ~ (0.90 to 0.95) × 33.705 kWh/ge × BEV range (mi) / mpge

    0.90 to 0.95 in the second formula is the charger efficiency.

    The car displays the kWh at the battery output (not the 240-V plug).

    You can plug in the EPA numbers to the formula to get the mi/kWh on the car display. Basically it is mpge divided by 33.705 and then divided by (0.90 to 0.95).

    mi/kWh at the battery output = (mpge / 33.705 kWh/ge) / (0.90 to 0.95)

    Gen 4 PHEV is more fuel-efficient (higher mi/kWh) than the Gen 5 PHEV.

    The EPA rating for Gen 4 PHEV is 25 miles. I get around 38 miles in the city and 30–33 miles on the highway.
     
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  4. iRun26.2

    iRun26.2 Active Member

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    Why would they go backwards (Gen 4 PHEV > Gen 5 PHEV)? And by how much?
     
  5. iRun26.2

    iRun26.2 Active Member

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    One thing I don’t understand, and I’m certain you do, is the usable battery charge on the Gen 5 PHEV. If they cut off the EV at 25% (I’ve read this someplace) and only let it charge to 90% to 95% (read this somewhere too), was is the usable EV kWhr available for Gen 5 PHE?. I’d like to know, based on the miles/kWh I see how far I could expect my car to go on EV