• iii@mander.xyz
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    3 hours ago

    That means the battery array would charge in 7-8hrs of sun, and provide nearly 16hrs of output at 1Gwh

    How many days a year does that occur? How much additional storage and production do you need add, to be able to bridge dunkelflautes, as is currently happening in germany, for example (1)?

    That’s why I mentioned the 90%, 99%, etc. If you want a balanced grid, you don’t need to just build for the average day (in production and consumption), you need to build for the worst case in both production and consumption.

    The worst case production in case for renewables, is close to zero for days on end. Meaning you need to size storage appropriatelly, in order to fairly compare to nuclear.

    • mosiacmango@lemm.ee
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      1 hour ago

      So you agree that solar + battery resolves 90-99% of power needs now at a drastically reduced cost and build time than nuclear today?

      I expect that 10% will get much closer to 1% in the next decade with all the versatile battery/solar tech coming onboard, but to compensate for solar fluctuations, you use wind, you use hydro, and you use the new “dig anywhere” steady state geothermal that is also being brought online today. We can run more HVDC lines to connect various parts of the country also. We are working on some now, but not enough. With a robust transmission system, solar gets 3hrs of “free” storage across our time zones. With better national connections, power flows from excess to where its needed, instead of being forced to be regional.

      Worst case? You burn green hydrogen you made with your excess solar capacity in retrofitted natgas plants.

      There are lots of answers to steady-state that are green and won’t take 15-20 years to come online like the next nuclear plant. We should keep going with them, because they can help us now and in the future.

      • iii@mander.xyz
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        30 minutes ago

        I’m saying you can get to 90% yes.

        But, as often happens, the last 10% is as hard or harder as the first 90%. The law of diminishing returns.

        There are lots of answers to steady-state that are green and won’t take 15 years

        I’m aware of and have studied them. But general public seems to greatly underestimate the scale of storage that’s needed. Germany, for example, consumes about 1.4TWh of electrical energy a day. That’s more than the world’s current yearly battery production. It does not suffice to power Germany, for one day.

        Pumped storage, if geology allows for it, seems like the only possible technology for sufficient storage.

        Demand side reduction is possible as well, but that’s simply a controlled gray out. The implications for a society are huge. Ask any cuban or south african.

        Others, like lithium ion batteries, green hydrogen, salt batteries, ammonium generation, … have been promised for decades now. Whilst the principle is there, they do store power, it simply does not scale to grid scaled needs.

        The sad part is that it sets a trap, like we in EU have fallen into. You get far along the way, pat yourself on the back with “this windmill powers a 1000 households” style faulty thinking. But as you can’t bridge the last gap, your reliance on fossil fuels, and total emissions, increases.