• ShortN0te@lemmy.ml
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    1 year ago

    There is no actual information on how self sufficient the car actually is. There is only 1 number which states how long the car drives on a sunny day with solar+battery combined.

    The car probably needs to charge for days via the solar panels in order to fill up the battery.

    • blazera@kbin.social
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      1 year ago

      Yeah, nothing on how much is pre-loaded battery and how much is solar charging, or how long the trip was.

      • chowder@lemmy.one
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        1 year ago

        None. It was entirely solar based. This is their 2nd vehicle smaller and lighter than the camper they made. So 440 ranged is fully charged, otherwise 620 miles in a week and a half off of just solar.

        week-and-a-half-long experiment

    • vrighter@discuss.tchncs.de
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      1 year ago

      there doesn’t need to be. It’s not. plain and simple. There just isn’t enough area on a car’s body (remember, most of them won’t even be oriented properly most of the time) for panels to generate enough power for self sufficiency. Even if the panels were 100% efficient. This will always be the case for any solar car.

      • HughJanus@lemmy.ml
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        1 year ago

        I mean that’s just not true unless you’re referring to the very narrow scope of powering itself while driving down the highway at 70MPH.

        With a sufficiently efficient design and enough solar panels and sun exposure, like can be seen on the Aptera, you can get 30-40 miles of range/day, which is more than sufficient for a daily commute.

        • vrighter@discuss.tchncs.de
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          1 year ago

          assuming average conditions, somewhere on the order of 20 kw at cruising speed. More is needed to accelerate.

          On the earth’s surface, we get about 1kw per meter squared of energy from the sun. That’s before factoring in inefficiencies in the panels, inefficiencies due to panels not oriented correctly, the battery charging system etc. Actual usable energy generated is significantly less than that.

          So, with 100% efficient panels, you would still need, in theory, at minimum around 20 meters squared of perfectly efficient, perfectly oriented panels. Probably about 3 to 4 times more, in practice. There just is not enough surface area on a car.