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I don't see you countering my argument, only attempting to ridicule it ("slighty more sophisticated", "trope", "these silly hippies", "been aware of the concept

by adwn 10mo ago

I don't see you countering my argument, only attempting to ridicule it ("slighty more sophisticated", "trope", "these silly hippies", "been aware of the concept of winter", "existence of winter as a gotcha"). That sucks, man :-( > If you want to critique their plans for dealing with it […] There are many ideas for seasonal storage of PV-generated electricity, but so far there is no concrete plan that's both scalable to TWh levels and economically feasible. Here on HN, there's always someone who'll post the knee-jerk response of "just build more panels", without doing the simple and very obvious calculation that 5x to 10x overprovisioning would turn solar from one of the cheaper into the by far most expensive power generation method out there [1]. [1] Except for paying people to crank a generator by hand, although that might at least help with obesity rates.

dinfinity 10mo ago
> 5x to 10x overprovisioning would turn solar from one of the cheaper into the by far most expensive power generation method out there. This is trivially false if the cost of solar generation (and battery storage) further drops by 5x to 10x. Additionally that implies the overprovisioned power is worthless in the summer, which does not have to be the case. It might make certain processes viable due to very low cost of energy during those months. Not trivial as those industries would have to leave the equipment using the power unused during winter months, but the economics could still work for certain cases. Some of the cases might even specifically be those that store energy for use in winter (although then we're not looking at the 'pure' overprovisioning solution anymore).
- adwn 10mo ago
  > This is trivially false if the cost of solar generation (and battery storage) further drops by 5x to 10x. That's a huge "if". The cost of PV panels has come down by a factor of 10 in the last 13 years or so, that's true. I doubt another 10x decrease is possible, because at some point you run into material costs. But the real issue is that price of the panels themselves is already only about 35% of the total installation cost of utility-scale PV. This means that even if the panels were free, it would only reduce the cost by a factor of 1.5.
  - dinfinity 10mo ago
    > But the real issue is that price of the panels themselves is already only about 35% of the total installation cost of utility-scale PV. This means that even if the panels were free, it would only reduce the cost by a factor of 1.5. 1. Do the other costs scale with the number of panels? Because if the sites are 5 times the scale of the current ones I would imagine there are considerable scale based cost efficiencies, both within projects and across projects (through standardization and commoditization). 2. Vertically mounted bifacial PV already greatly smoothes the power production curve throughout the day, improving profitability. Lower cost panels make the downside of requiring more panels in such a setup almost non-existent. Additionally, they reduce maintenance/cleaning costs by being mounted vertically. 3. Battery/energy storage (which further improve profitability) costs are dropping and can drop further. Also, please address the matter of using the overprovisioned power in summer. Possible projects are underground thermal storage ("Pit Thermal Energy Storage", only works in places where heating is required in winter), desalination, producing ammonia for fertilizer, and producing jet fuel.
    - adwn 10mo ago
      > 1. Do the other costs scale with the number of panels? Mostly yes. Once you're at utility-scale, installation and maintainance should scale 1:1 with number of panels. Inverters and balancing systems should also scale 1:1, although you might be able to save a bit here if you're willing to "waste" power during peak insolation. But think about it this way: If it was possible to reduce non-panel costs by a factor of 5 simply by building 5x larger solar plants, the operating companies would already be doing this. With non-panel costs around 65%, this would result in 65% * (1 - 1/5) = 52% savings and give them a huge advantage over the competition. > 2. Vertically mounted bifacial PV […] 3. Battery […] costs are dropping I agree that intra-day fluctuations will be solved by cheaper panels and cheaper batteries, especially once sodium-ion battery costs fall significantly. But I'm specifically talking about seasonal storage here. > Also, please address the matter of using the overprovisioned power in summer. I'm quite pessimistic about that. Chemical plants tend to be extremely capital-intensive and quickly become non-profitable if they're effectively idle during half of the year. Underground thermal storage would require huge infrastructure investments into distribution, since most places don't already have district heating. Sorry, very busy today so I can't go into all details, but I still wanted to give you an answer.
adrianN 10mo ago
What amounts to „concrete plan“? Right now we’re still in the state where building more generation is the best use of our money with batteries for load shifting a few hours ramping up. So it’s entirely expected that there is no infrastructure for seasonal storage yet. However the maths for storing energy as hydrogen and heat looks quite favorable and the necessary technology exists already.
- adwn 10mo ago
  "Concrete plan" means a technology which satisfies all of these requirements: 1) demonstrated ability in a utility-scale plant 2) already economically viable, or projected to be economically viable within 2 years by actual process engineers with experience in scaling up chemical/electrical plants to industrial size Yes, that's hard to meet. But the thing is, we've seemingly heard of hundreds of revolutionary storage methods over the last decade, and so far nothing has come to fruition. That's because they were promised by researchers making breakthroughs in the lab, and forecasting orders of magnitude of cost reductions. They're doing great experimental work, but they lack the knowledge and experience to judge what it takes to go from lab result to utility-scale application.
  - adrianN 10mo ago
    Electrolysis hydrogen is only a little bit more expensive than hydrogen derived from methane and electrolyzers with dozens of megawatt are available. That seems pretty solid to me at this point in the energy transition.
    - adwn 10mo ago
      Hydrogen generation isn't the problem, storing it over several months is. Economical, safe, and reliable storage of hydrogen is very much an unsolved engineering challenge. If it weren't, hydrogen storage plants would shoot out of the ground left and right: Even here in Germany, we have such an abundance of solar electricity during the summer months that wind generators have to be turned off and the spot price of electricity still falls to negative values(!) over noon, almost every day.

by adwn 10mo ago

dinfinity 10mo ago

> 5x to 10x overprovisioning would turn solar from one of the cheaper into the by far most expensive power generation method out there. This is trivially false if the cost of solar generation (and battery storage) further drops by 5x to 10x. Additionally that implies the overprovisioned power is worthless in the summer, which does not have to be the case. It might make certain processes viable due to very low cost of energy during those months. Not trivial as those industries would have to leave the equipment using the power unused during winter months, but the economics could still work for certain cases. Some of the cases might even specifically be those that store energy for use in winter (although then we're not looking at the 'pure' overprovisioning solution anymore).

adwn 10mo ago
> This is trivially false if the cost of solar generation (and battery storage) further drops by 5x to 10x. That's a huge "if". The cost of PV panels has come down by a factor of 10 in the last 13 years or so, that's true. I doubt another 10x decrease is possible, because at some point you run into material costs. But the real issue is that price of the panels themselves is already only about 35% of the total installation cost of utility-scale PV. This means that even if the panels were free, it would only reduce the cost by a factor of 1.5.
- dinfinity 10mo ago
  > But the real issue is that price of the panels themselves is already only about 35% of the total installation cost of utility-scale PV. This means that even if the panels were free, it would only reduce the cost by a factor of 1.5. 1. Do the other costs scale with the number of panels? Because if the sites are 5 times the scale of the current ones I would imagine there are considerable scale based cost efficiencies, both within projects and across projects (through standardization and commoditization). 2. Vertically mounted bifacial PV already greatly smoothes the power production curve throughout the day, improving profitability. Lower cost panels make the downside of requiring more panels in such a setup almost non-existent. Additionally, they reduce maintenance/cleaning costs by being mounted vertically. 3. Battery/energy storage (which further improve profitability) costs are dropping and can drop further. Also, please address the matter of using the overprovisioned power in summer. Possible projects are underground thermal storage ("Pit Thermal Energy Storage", only works in places where heating is required in winter), desalination, producing ammonia for fertilizer, and producing jet fuel.
  - adwn 10mo ago
    > 1. Do the other costs scale with the number of panels? Mostly yes. Once you're at utility-scale, installation and maintainance should scale 1:1 with number of panels. Inverters and balancing systems should also scale 1:1, although you might be able to save a bit here if you're willing to "waste" power during peak insolation. But think about it this way: If it was possible to reduce non-panel costs by a factor of 5 simply by building 5x larger solar plants, the operating companies would already be doing this. With non-panel costs around 65%, this would result in 65% * (1 - 1/5) = 52% savings and give them a huge advantage over the competition. > 2. Vertically mounted bifacial PV […] 3. Battery […] costs are dropping I agree that intra-day fluctuations will be solved by cheaper panels and cheaper batteries, especially once sodium-ion battery costs fall significantly. But I'm specifically talking about seasonal storage here. > Also, please address the matter of using the overprovisioned power in summer. I'm quite pessimistic about that. Chemical plants tend to be extremely capital-intensive and quickly become non-profitable if they're effectively idle during half of the year. Underground thermal storage would require huge infrastructure investments into distribution, since most places don't already have district heating. Sorry, very busy today so I can't go into all details, but I still wanted to give you an answer.

adrianN 10mo ago

What amounts to „concrete plan“? Right now we’re still in the state where building more generation is the best use of our money with batteries for load shifting a few hours ramping up. So it’s entirely expected that there is no infrastructure for seasonal storage yet. However the maths for storing energy as hydrogen and heat looks quite favorable and the necessary technology exists already.

adwn 10mo ago
"Concrete plan" means a technology which satisfies all of these requirements: 1) demonstrated ability in a utility-scale plant 2) already economically viable, or projected to be economically viable within 2 years by actual process engineers with experience in scaling up chemical/electrical plants to industrial size Yes, that's hard to meet. But the thing is, we've seemingly heard of hundreds of revolutionary storage methods over the last decade, and so far nothing has come to fruition. That's because they were promised by researchers making breakthroughs in the lab, and forecasting orders of magnitude of cost reductions. They're doing great experimental work, but they lack the knowledge and experience to judge what it takes to go from lab result to utility-scale application.
- adrianN 10mo ago
  Electrolysis hydrogen is only a little bit more expensive than hydrogen derived from methane and electrolyzers with dozens of megawatt are available. That seems pretty solid to me at this point in the energy transition.
  - adwn 10mo ago
    Hydrogen generation isn't the problem, storing it over several months is. Economical, safe, and reliable storage of hydrogen is very much an unsolved engineering challenge. If it weren't, hydrogen storage plants would shoot out of the ground left and right: Even here in Germany, we have such an abundance of solar electricity during the summer months that wind generators have to be turned off and the spot price of electricity still falls to negative values(!) over noon, almost every day.