cross-posted from: https://lemmy.world/post/22892955

The Prius Prime is a dual fuel vehicle, able to run 100% on Electric, or 100% on gasoline, or a computerized blend in-between. This presents me a great opportunity to be able to do a direct comparison with the same car of an EV engine vs an ICE engine.

  • Toyota computer claims 3.2mi-per-kwhr.

  • Kill-a-watt (https://en.wikipedia.org/wiki/Kill_A_Watt) claims 2.2mi-per-kwhr.

  • Additional 1.5% losses should be assumed in the wires if you wish. (120V drops down to 118V during charging, meaning 2V of the energy was lost due to the resistance of my home’s wires).

  • Level 1 charger at home (known to be less efficient).

  • Toyota computer claims 53miles-per-gallon (American Gallon).

  • I have not independently verified the gallon usage of my car.

  • 295 miles driven total, sometimes EV, sometimes Gasoline, sometimes both.

  • 30F to 40F (-1C to 4.5C) in my area this past week.

  • Winter-blend fuel.

  • 12.5miles per $electricity-dollar (17.1c / kw-hr home charging costs)

  • 17.1 miles per $gasoline-dollar ($3.10 per gallon last fillup).

If anyone has questions about my tests. The main takeaway is that L1 charging is so low in efficiency that gasoline in my area is cheaper than electricity. Obviously the price of gasoline and electricity varies significantly area-to-area, so feel free to use my numbers to calculate / simulate the costs in your area.

There is also substantial losses of efficiency due to cold weather, that is well acknowledged by the EV community. The Prius Prime (and most other EVs) will turn on a heater to keep the battery conditioned in the winter, spending precious electricity on battery-conditioning rather than miles. Gasoline engines do not have this problem and remain as efficient in the winter.

  • @dragontamerOPMEnglish
    1•5 days ago

    At -1 my range loss was only like 15-20%.

    Measured from the wall or your car’s computer?

    Because my L1 charger is clearly loosing a lot of electricity here in the winter. I’m pretty sure its the battery-heater that’s using much a substantial amount of power and losing efficiency.

    To get 11kWh into the battery, I needed over 13.5kWh (2.5kw-hr of losses between the wall and the battery). I expect the 15% to 20% loss to only be the “running battery during winter” penalty, but you’re missing the 2nd ping when the heater must turn on for the battery during charging at night.

    Note that I have an inefficient L1 charger and I do plan to upgrade to L2 eventually. (3 hours of heater instead of 10-hours of heater overnight will clearly improve my charging efficiency, but then I lose the ability to measure the energy at the wall).

    • NomecksEnglish
      2•4 days ago

      So how much does it cost to drive your Prius 100km?

      • @dragontamerOPMEnglish
        2•4 days ago

        $4.50 in electricity, or $3.63 in gasoline.

        Which is a bit surprising to me. All the pro-EV people were making it sound like EVs were way cheaper…

        EDIT: Today it is 50F in my area and the Electric costs have dropped down significantly. I’m estimating about $3.20 in electricity costs when the temperature is 50F.

        100km in 0C is $4.50 in electricity

        100km in 10C is $3.20 in electricity. Holy shit, it’s a huge difference.

          • @dragontamerOPMEnglish
            2•4 days ago

            Wait wait wait. You followed my posts to a different topic on a different community? OMFG that’s hilarious.

            I’m glad that I’m living in your head rent-free.