• KoboldCoterie
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    1 year ago

    This is very neat. I wonder what the energy loss is, between what’s required to lift the water and what’s gained by releasing it. Regardless, eco-friendly high density “batteries” are a great concept.

    • RickRussell_CA@lemmy.world
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      1 year ago

      It’s probably very low efficiency, but if you can design renewable energy systems to provide enough overage during peak generation periods, maybe it doesn’t matter.

      As an example, MKBHD’s solar roof produces something like 30KW during peak sunlight, which is so much more than his home uses (even with air conditioning turned on) that it can charge his house batteries to 100% and gives him power to sell back to the electric company for future power credits.

      Admittedly, not everybody has a house with a large roof or $120K to spend on solar. But if we can drive solar and wind power down enough in price per unit, the efficiency of the storage system becomes a lot less of a concern.

      • flawedFraction@lemmy.world
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        1 year ago

        A system like this is designed to use excess generated power during times of low demand and then to put power back into the grid during peak usage times. This can help negate the need to bring another plant online and they can probably sell the power at higher prices during peak usage.

        • Rivalarrival@lemmy.today
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          1 year ago

          Pumped storage is great, but it is only a partial answer. You describe the “supply shaping” aspect of grid management, where we assume the demand for power is outside of our control, and we adjust our supply to meet whatever is being demanded. The problem is that pumped storage is not scalable. There are only so many places you can build reservoirs.

          We need to focus on “demand shaping”. Instead of (or rather, in addition to) putting power into storage so we can take it back out at a different time of the day, we need to shift our consumption of power so it is used when it can be produced.

          Supply shaping is the flattening and shifting of the supply peak to match the demand peak. It is far more efficient and scalable to flatten and shift the demand peak to match supply.

          We need large appliances like home and commercial water heaters and deep freezers to be directly aware of grid conditions and temporarily adjust their setpoints a few degrees.

          Steel production, aluminum smelting, and other heavy industries are commonly done overnight during the demand trough, where they increase the base load and reduce reliance on peaker plants. They need to be shifted to daytime operation during the supply peak.

          We need massive energy sinks such as desalination plants, hydrogen electrolysis plants, and Fischer-Tropsch synfuel production plants collocated with and powered by solar, wind, wave, and tidal energy facilities. They need to suck up any cheap, free, or “negative rate” power they can get, but shut down production and back feed the grid with their own generation when prices rise during the day.

          • InvertedParallax@lemm.ee
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            1 year ago

            It would take Musk all of 5 seconds of his “giant megabrain” to tell his cars to talk to each other and power companies to enable load management of charging.

            So of course he won’t.

            Power companies are just places to put dumb relatives of politicians nowadays anyway, they’re slush funds with hard hats.

      • Edgelord_Of_Tomorrow@lemmy.world
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        1 year ago

        Yeah at the end of the day renewable energy is rapidly becoming pretty close to free. Efficiency doesn’t matter as much when the energy costs nothing to generate.

    • Qualanqui@lemmy.nz
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      1 year ago

      If you have the system always running most of the cartage back to the top could be handled by the siphoning effect, like draining a washing machine or siphoning patrol.

      You’d need energy to get it started but after that it should keep siphoning as long as there’s liquid to siphon.

      • KoboldCoterie
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        1 year ago

        I don’t understand how that would work in this case; if this is true, I think I’d need to see a diagram.

        My understanding is that they use energy to pump the liquid up during times of excess, and release it to generate energy when there’s more demand.