Ultra-white ceramic cools buildings with record-high 99.6% reflectivity::undefined

  • Treczoks@lemmy.world
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    10 months ago

    Probably illegal here because of the high reflective value. Depending on the sun’s position, it could dazzle and blind people, e.g. people driving cars or riding bikes. I know that for this reason, shiny metal roofs are not allowed.

    • KapiteinPoffertje@lemmy.world
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      10 months ago

      There is a difference between mirror like reflection and diffuse reflection. Mirror reflection is what you get with metal roofs which beam the sun directly to a target resulting in one spot being blinded. Diffuse reflection will spread it around, resulting in more light all around which is what we can handle as humans.

      • Jojo@lemm.ee
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        10 months ago

        Can mostly handle. Snow blindness is a thing, and that’s all diffuse reflection too, not specular. But it’s unlikely a roof would be such a problem.

        • intensely_human@lemm.ee
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          10 months ago

          The reason for snow blindness is the fact the snow fills such a high portion of the visual field.

          • Jojo@lemm.ee
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            10 months ago

            Yeah, hence it’s unlikely a roof would fill it to the same extent and wouldn’t be a problem.

    • AstridWipenaugh@lemmy.world
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      10 months ago

      It’s not visibly reflective. Yes, it’s white, but it’s cool to the touch because the majority of the energy is radiated out into space via non-visible wavelengths. Someone has already posted a great YouTube video from Night Hawk In Light in a comment where he explains how this tech works and makes his own paint!

    • ladicius@lemmy.world
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      10 months ago

      I have aluminium foil covering my windows in summer and that doesn’t blind anyone by far, even in full sunlight.

      Not everything reflecting is a mirror.