• kent_eh
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    1 year ago

    Regenerative braking has more influence on battery charge in stop-and-go traffic than it does on thw highway

    • Ecksell@lemmy.one
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      1 year ago

      You beat me to it, regenerative braking is strong in modern EVs. In several of them you can one-foot drive them, meaning take your foot off the throttle pedal, and the generator(s) will start harvesting hard enough to slow the car to a stop, charging the batteries the whole time. You only need the brake to emergency stop. And if you do choose to brake, you are just harvesting even more energy.

    • semibreve42@lemmy.dupper.net
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      1 year ago

      As well, EV’s lose very little of their energy to heat or other losses between the battery and wheels unlike ICE vehicles. The result is drag plays a more significant percentage of where the energy is “going”, so the impact of higher speeds on range is greater then it is for ICE vehicles.

    • JoJo@social.fossware.space
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      1 year ago

      This was a lab test so regenerative braking didn’t factor, they just measured how much power they got from discharging the battery at full vs half load.

      If you draw more power from a battery, you get more voltage drop. Voltage drop is a measure of the power lost (heat generated) within the battery and circuitry and it’s the internal resistance of the battery plus circuitry multiplied by the amps drawn. More power = more amps = more losses. This is why higher power applications use higher voltage battery packs because higher voltages mean fewer amps and smaller losses (power = amps x volts).

  • PerogiBoi
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    1 year ago

    Something about intermittent power draw vs. constant draw.

    I have the same effect on my electric dirtbike. I get a lot more mileage off-road up and down hills at 15-40km/h than I do on flat road at 70 km/h.

  • B0rax@feddit.de
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    1 year ago

    Next you tell us that they have more mileage in moderate temperatures rather than in the winter or the summer…

    • Bad_Company_Daps
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      1 year ago

      The reason this is interesting is because it’s the reverse of gas cars. Typically the best efficiency of a gas vehicle is on the highway but for EVs you get much more efficiency in local streets

      • B0rax@feddit.de
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        1 year ago

        Well that’s only true if you don’t drive fast. When you go above 120 km/h you will see that the fuel consumption increases noticeably

      • seang96@spgrn.com
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        1 year ago

        The top commenter was pointing out this is extremely obvious and known which makes it less interesting.

  • dark_stang@beehaw.org
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    1 year ago

    This is something everybody with an ev already knows. Drag is a big factor at high speeds. But under 40mph (65kph) it’s pretty negligible. If you did a constant 30mph you could probably triple your estimated range.

    With an ICE vehicle, you’re wasting a lot of energy at low speeds being inefficient. But with an electric motor, you’re always using exactly as much energy as needed to move.

  • Irina@beehaw.org
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    1 year ago

    Well, yeah? Electric motors require more energy to go faster, and a petrol car has gearing to solve this problem. The slower you drive in an EV, the more range you get.

    • dark_stang@beehaw.org
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      1 year ago

      It’s the drag that reduces range at higher speeds. I even get better range in CO because the wind is thinner up here.