• wabafee@lemmy.world
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    10 months ago

    We’ll probably be able to harvest solar power from space then beam it to Earth in a practical way first, than nuclear fusion becomes practical.

      • aidan@lemmy.world
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        10 months ago

        It’s not efficient, a huge amount of it gets diffused or absorbed

        • Knock_Knock_Lemmy_In@lemmy.world
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          10 months ago

          It doesn’t need to be efficient. Capture all the light that hits earth for 5 minutes and that’s the world energy demand for a year.

        • Cosmic Cleric@lemmy.world
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          10 months ago

          It’s not efficient, a huge amount of it gets diffused or absorbed

          The amount that’s left over though is more than enough, especially with today panels which only convert a very small percentage of that remaining energy.

          As the panels improve even more they’ll be a very large energy surplus, even with how much solar light actually gets through the atmosphere.

        • Furbag@lemmy.world
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          10 months ago

          Wow, you’re right! We should just build a Dyson sphere around the sun. 100% efficiency achieved. What could possibly go wrong?

          • GojuRyu@lemmy.world
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            10 months ago

            Did you understand the person you respond to as saying its inefficient because the sun shines in other directions than the array proposed?
            I’m pretty sure the person talked specifically about the beam from the array to earth being inefficient.

      • excitingburp@lemmy.world
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        10 months ago

        The nice thing about space is that there isn’t any weather up there to make the solar panels dirty etc. There’s also a lot of space, which solar panels need a lot of.

          • nymwit@lemm.ee
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            10 months ago

            Microwave transmission is what’s usually said, then someone says anything in the beam’s path will get zapped, then it’s pointed out the energy density isn’t that high. Just wanted to shortcut that for ya

          • Cosmic Cleric@lemmy.world
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            10 months ago

            How would you move the power down to earth?

            Last time I read up on it it was via converting the energy into microwaves and beaming it down.

            • excitingburp@lemmy.world
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              10 months ago

              I think masers (microwave lasers) are the new theory for achieving this, previously it was beaming microwave down much like your microwave oven beams your food.

          • cygnosis@lemmy.world
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            10 months ago

            Funny thing is, no matter how you arrange to do that it becomes a de-facto death ray. Stick a terawatt of solar panels in space, use the power to shine a laser/maser down to earth, then build a station to turn the laser power back to electricity? Great, until some hacker figures out how to control where the laser is pointed. Then you get Dr. Evil holding the world for ransom.

            • Dogyote@slrpnk.net
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              10 months ago

              Nah it’s not really bad at all:

              The use of microwave transmission of power has been the most controversial issue in considering any SPS design. At the Earth’s surface, a suggested microwave beam would have a maximum intensity at its center, of 23 mW/cm2 (less than 1/4 the solar irradiation constant), and an intensity of less than 1 mW/cm2 outside the rectenna fenceline (the receiver’s perimeter). These compare with current United States Occupational Safety and Health Act (OSHA) workplace exposure limits for microwaves, which are 10 mW/cm2,[original research?] - the limit itself being expressed in voluntary terms and ruled unenforceable for Federal OSHA enforcement purposes.[citation needed] A beam of this intensity is therefore at its center, of a similar magnitude to current safe workplace levels, even for long term or indefinite exposure.

              https://en.wikipedia.org/wiki/Space-based_solar_power?wprov=sfla1

        • Cosmic Cleric@lemmy.world
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          10 months ago

          The nice thing about space is that there isn’t any weather up there to make the solar panels dirty etc.

          There’s a lot of junk though can that can damage those panels.

      • TIMMAY@lemmy.world
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        10 months ago

        We dont need to collect it in space, just direct more of it to certain ground based collectors?

    • Rutty@sh.itjust.works
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      10 months ago

      I’m not sure what comment to reply to, but I feel obligated to remind people that the sun is a fusion reaction.

      • TrueStoryBob@lemmy.world
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        10 months ago

        Basically, the idea is to build orbital solar farms (where is always sunny), then beam the energy produced back to the ground with microwave transmitters and ground recievers. It’s technically feasible, unlike fusion we have all the technology needed to do it right now. However, it’s cost and resource prohibitive. The US government studied building such a system in the 1970-80’s after the energy crisis. We could do it, but building it would take a generation to get running and about double the US’s current military annual budget. Launch costs are coming down since then, but the industrialization of space and the moon will take generations and would need to be an international effort to have any chance of success.

    • CileTheSane@lemmy.ca
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      10 months ago

      We’ll probably be able to harvest solar power from space then beam it to Earth in a practical way first, than nuclear fusion becomes practical.

      You mean solar panels?