Comment by direwolf20

15 hours ago

And this is an expected problem with renewables that can be engineered around. It's unlikely the whole world has a drought at once during a calm night, so developing ways to transmit power long distances will be important.

Or just use nuclear as base load, and battery storage as much as you can.

  • The economics of new nuclear plants don't make sense. They take too long to build and cost too much. By the time a new plant is ready, alternate sources (likely solar + battery and long-distance HVDC) will have eaten its lunch.

    • > They take too long to build and cost too much.

      The global average to build one is ~7 years. People have been saying they take too long to build as an excuse for not building them for what, two decades or more? It seems to be taking longer to not build them than to build them.

      > By the time a new plant is ready, alternate sources (likely solar + battery and long-distance HVDC) will have eaten its lunch.

      Neither of those have the same purpose. Solar + battery lets you generate power with solar at noon and then use it after sunset. It doesn't let you generate power with solar in July and then use it in January. More than a third of US energy consumption is for heating which is a terrible match for solar because the demand is nearly the exact inverse of solar's generation profile both in terms of time of day and seasonally.

      HVDC is pretty overrated in general. It does nothing for the seasonal problem and it's expensive for something that only provides a significant benefit a small minority of the time, i.e. the two days out of the year when the entire local grid has a shortage but a far away one has a surplus. It's also hard to secure because it inherently spans long distances so you can't have anything like a containment building around it and you end up with an infrastructure where multiple GW of grid capacity is susceptible to accidental or purposeful disruption by any idiot with a shovel or a mylar balloon.

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    • How much of this is unnecessary regulatory burden, though? There probably is some margin of improvement over what the anti-nuclear lobbyists have imposed.

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  • Or just gradually taper off fossil fuel use until storage and renewables carry everything.

    Exactly what "storage" means there is the key, especially at high latitude. Do not assume just batteries.

  • Nuclear doesn't really solve this particular problem - solar is already cheaper than nuclear, so no one is going to replace their entire solar capacity with nuclear. And nuclear doesn't spin up/down rapidly like natural gas, so its a lousy solution for nighttime.

    • This is just wrong. Nuclear is perfectly fine for nighttime because nighttime is highly predictable and doesn't fluctuate very much.

      My state (NSW, Australia) for example uses no less then 6 GW at all times of day. Variable load is on top of that during the day.

      If we had 6GW of nuclear plants, our grid would be almost completely green and they'd run at 100% utilization.

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  • You don't need battery storage if you've got hydro.

    You need solar. Make hydro the backup, fill reservoirs as your reserve and sell extra energy when they're nearly full.

    • I can see this makes sense especially for medium term storage. A lot full of batteries is great for the next ten seconds, next ten minutes, even to some extent the next ten hours, but it surely doesn't make much sense to store ten days of electricity that way compared to just keeping the water behind a dam. We know that many of the world's large dams are capturing snow melt or other seasonal flows, running them only when solar or wind can't provide the power you need lets you make more effective use of the same resource.

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    • There are two types of hydro - run of river, and ones with large lake storage. You need the ones with large lake storage, rather that the ones with a lake to build a head.

    • Pumped hydro storage only holds about 8-12 hours of power. To be economically viable to build you need to cycle it daily.

      It uses enormous amounts of land and capital to build, and is ongoingly dangerous in a unique way. If LiFePO4 can do 4 hours at full output already, and be placed anywhere using volume manufacturing to expand, then batteries are straight up better.

      Pumped hydro is an expensive dead end.

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  • Over-provisioning with renewables is cheaper

    • Which of course is why the countries that do that the most have the highest energy costs in the world. And just for fun, they usually have some of the dirtiest grids because of all the drawbacks of renewables.

  • Get a drought and you have to shut them down, ask France.

    "Base load" is just some nonsense from nuclear fans to get the cost per GWh down.

    • Base load is an industry term coined by the very engineers who make the grid work. But I'm sure a random poster on an Internet forum knows more than the engineers who actually do the work.

      PS France has the cleanest grid in Europe

  • Nuclear seems to be the worst option:

    You can't quickly change the amount of power it generates. Which is what you need if you want to use it together with dirt cheap solar.

    It's very expensive. In fact, noone knows how expensive it will end up being after a couple thousand of years.

    It's dangerous. For millenia. Vulnerable to terrorism. Enabler of nuclear weapons.

    It takes a long time to build and bring online.

    It doesn't scale down.

    Finally, Kasachstan is the major producer of Uranium. Yay?

    • > You can't quickly change the amount of power it generates. Which is what you need if you want to use it together with dirt cheap solar.

      You always need something in the grid that can change the amount of power it generates regardless of what you use in combination with it, because the demand from the grid isn't fixed. All grids need something in the nature of storage/hydro or peaker plants.

      The advantage of combining solar with nuclear is that their generation profiles are different. Nuclear can generate power at night and doesn't have lower output during the peak seasonal demand period for heating. Nuclear is baseload; it doesn't make sense to have more of it than the minimum load on the grid, but no one is really proposing to. The minimum load is generally around half of the maximum load.

      > It's very expensive. In fact, noone knows how expensive it will end up being after a couple thousand of years.

      If you actually reprocess the fuel there is no "couple thousand of years". If you instead put it in a dry hole in the desert, you have a desert where nobody wanted to live to begin with that now has a box of hot rocks sealed in it. It's not clear how this is supposed to cost an unforeseeable amount of money.

      > Vulnerable to terrorism.

      Nuclear plants are kind of a hard target. The stuff inside them isn't any more of a biohazard than what's in a thousand other chemical/industrial plants that aren't surrounded in thick concrete.

      > Enabler of nuclear weapons.

      The US already has nuclear weapons and would continue to do so regardless of how much electricity is generated from what sources. The argument against building nuclear reactors in Iran is not an argument against building nuclear reactors in Ohio.

      > It takes a long time to build and bring online.

      Better get started then.

      > It doesn't scale down.

      Decent argument for not having one in your house; not a great argument for not having one in your state.

      > Finally, Kasachstan is the major producer of Uranium. Yay?

      The country with the largest uranium reserves is Australia. Kazakhstan is #2 and has about the same amount as Canada. Other countries with significant reserves include Russia, India, Brazil, China, Ukraine and several countries in Africa. The US has some itself and plenty of other places to source it. It can also be extracted from seawater.

      The US is also in the top 4 for thorium reserves with about 70% as much as the #1 (which is India), and thorium is 3-4 times more abundant overall than uranium.

Having a continent-wide draught (or cold winter or other weather effect) is rather common though. Just a few years back Europe had a massive issue where draught caused both drop of hydro production and cooling for French nukes, causing energy prices to spike.

  • No. Cooling french nukes was never a problem. In that period France was net exporting 14GW. Cooling in general isn't a problem - some modulation is done just to save fish.

    Maybe you are confusing with 2022 when half of french fleet was shut down to check for potential pipe cracks/corrosion esp in one of their reactor designs due to poor geometry. But that's unrelated to droughts

  • Cooling for French nuclear reactors, yes. More than once since 2020. But nukes?