Comment on power generator

frank@sopuli.xyz ⁨5⁩ ⁨days⁩ ago

• marcos@lemmy.world ⁨5⁩ ⁨days⁩ ago

  Take a look at reverse electro-dialysis.

  It’s pushing thermal energy into electricity directly by the force of entropy.

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  • bitjunkie@lemmy.world ⁨5⁩ ⁨days⁩ ago

    The what now

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    • marcos@lemmy.world ⁨5⁩ ⁨days⁩ ago

      Entropy is maximized by turning heat into electricity, so electricity appears on the device, as it gets cooler (by a tiny amount).

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  • frank@sopuli.xyz ⁨5⁩ ⁨days⁩ ago

    Yeah, it’s a super rad tech! A bit pricey but a neat renewable that almost generates opposite to solar in a way, in that if it’s raining you’re getting some energy in the form of fresh water

    Can you ELI10 an intuitive explanation on why the salinity gradient provides energy? It doesn’t make intuitive sense to me and never has. Like why is fresh water mixing with salt water energy positive?

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    • marcos@lemmy.world ⁨5⁩ ⁨days⁩ ago

      why the salinity gradient provides energy?

      It doesn’t. It’s the thermal energy that is converted to electricity.

      The salinity gradient provides an entropy dump. The dialysis machine is built in a way that the only possible way for that entropy to increase is by generating some electricity.

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    • rain_enjoyer@sopuli.xyz ⁨4⁩ ⁨days⁩ ago

      when you dissolve salt in water, then salt splits into ions and each can hold up specific number of water molecules, which means that this water can’t do water things. so on top of salt’s physical presence, there’s a fraction of water that can’t water, or salt water is less watery in a sense than fresh water. now it turns out, if you put a membrane between these two that allows water through but not salt, water goes to higher salinity on its own, because there’s less watery there. how hard it happens is quantified as osmotic pressure and it can be in tens of atmospheres. reverse electrodialysis is just a clever arrangement that avoids energy recovery from low volume of high pressure liquid, like how reverse of reverse osmosis would work

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• Lost_My_Mind@lemmy.world ⁨5⁩ ⁨days⁩ ago

  Your name makes me think you’re about to lather your own naked body in vasoline, and hide inside the couch.

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  • frank@sopuli.xyz ⁨5⁩ ⁨days⁩ ago

    I’m known to lather a bit, as a treat.

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• Rooskie91@discuss.online ⁨5⁩ ⁨days⁩ ago

  Personally, I like the mirror plants that use the suns energy to superheat salt.

  And then use that to boil water. /s

  For real, what China is doing with PVs is pretty fucking cool.

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