If I had a strong source of radio-frequency photons, can these be converted to electricity like a solar panel does for light?

  • Admiral Patrick
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    12 hours ago

    Rectenna

    It’s the basis for the receiving end of “beaming” power (long distance; not the induction kind used in wireless chargers).

    • @fargeol
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      1311 hours ago

      Oh, it’s Rectifying antenna! Phew!

    • @[email protected]OP
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      311 hours ago

      I like that there’s a direct analog for light and it makes use of semiconductor as well.

      • @Treczoks
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        110 hours ago

        You can “receive” and therefore energy-harvest infrared with semiconductor antennas and circuits. Still a research thing, but could be an interesting add-on on the back of solar panels one day.

  • @[email protected]
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    58 hours ago

    Yes, these devices exist. But, IR is significantly, even several orders of magnitude, less powerful from the sun than visible and UV light. The only applications derive from receiving power from human sources that are bright enough, some examples are here in the other comments.

    Even then, I have doubts that human IR emitters produce enough power for anything but the most highly efficiently engineered device, outside of a microwave.

  • hendrik
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    1612 hours ago

    That would be an antenna or a coil, if you’re trying to harvest electromagnetic fields.

  • slazer2au
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    12 hours ago

    Isn’t this essentially near field charging like Qi Charging?

    • Natanael
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      311 hours ago

      Also microwave projection is used sometimes for power transfer at a distance (mostly stuff like between mountaintops or islands, also only in clear weather)

      • slazer2au
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        111 hours ago

        The amount of free air loss would be horrific. Spend the money on a subsea power cable at that point.

  • FuglyDuck
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    17 hours ago

    You mean like…. Inductive power transmission? Like every modern cell phone uses?

    It’s been around for quite a while, actually, and chances are solid, you use it every day without realizing it.

    Nikola Tesla worked on it because he wanted to create a sort of electromagnetic shield that would prevent any sort of attack. The problem with the shield was it would- theoretically-prevent all the -modern attacks. (It sort of worked. The problem was it required horrible amounts of power, just for a single tower, would require a massive power grid and still had the problem of frying any bit of metal. Details.)

    The inductive power transmission actually worked quite well, besides the efficiency involved in the inverse square law.

    Which, brings us to the new-modern era, with inductive charging for devices- electric toothbrushes were the first since it let you seal the toothbrush and still charge it- then we see it in RFID type things

    the RF powers a chip that modulates the carrier wave and rebroadcasts something different. This is used for access control, mostly, but it was basically the same thing as The Thing- a Soviet era bug in the US’s embassy in Moscow. Located in the seal they gifted. This is also used when you “tap” credit or debit cards.

    We also see it while charging phones, or apple watches or anything like that.

    The reason it’s all relatively low-power is that as you increase in power, it becomes increasingly inefficient. Horribly so.