From a grid stability point, you can’t produce more than is used, else you get higher frequencies and/or voltages until the automatics shut down. It’s already a somewhat frequent occurence in germany for the grid operator to shut down big solar plants during peak hours because they produce way more power than they can dump (because of low demand or the infrastructure limiting transfer to somewhere else)
Negative prices are the grid operator encouraging more demand so it can balance out the increased production.
As someone with a technical background this is the stupidest problem with solar that I don’t get… just turn off the panels in groups until generation is closer to demand… how have engineers not figured that out. And if they have why does this still get written about.
I’m adjacent to this problem, so I have a little context, but am not an expert at all.
To my knowledge, we don’t have granular control over panels. So we can shut off legs of a plant, but that’s a lot of power to be moving all at once.
Instead, prices are set to encourage commercial customers to intake more power incrementally. This has a smoother result on the grid, less chance of destabilizing.
A customer like a data center could wait to perform defragmentation or a backup or something until the price of power hits a cheap or negative number.
Well I wasn’t expecting to find THE right answer in the comments already. Kudos!
And to everyone reading through this post: If you have questions, need more explanations or want to learn more about the options that we have to “stabilize” a renewable energy system and make it long term viable, just ask!
But the thing is, you CAN simply turn them off at the press of a button (or an automated script) so its really a complete non issue. As long as big solar installations control systems are accessible by the grid operators, it should be fine.
If you’re spending billions to build a solar plant that has to turn off all the time during peak hours then you’re wasting your money. That seems like a fundamental issue to me, not a non-issue.
Are there any solar plants that cost a billion dollars each?
Secondly, you want to over build solar, so that you have enough capacity during off peak hours. Grid storage is obviously the better solution, but seems not widely available enough yet.
Ok, but what do you do when you’re short of power at night? Keep in mind to turn on conventional power stations it’s expensive & time consuming. Once they startup they need to stay on for a long while to be efficient & cheap.
The real solution is to store excess power in batteries. Lithium ion is too expensive to scale, Sodium ion batteries are economically & capacity viable AFAIK.
I’ve read that gravity batteries and sand batteries are ecologically sound options that work on the scale needed to support large sections of the electrical grid.
that work on the scale needed to support large sections of electrical grid
That first link is for a 10MW, 8 hour battery. 10MW is on the smaller end of generators, you’d need quite a few of these to start making an impact. For example, a small gas turbine is like 50MW, a large one is over 250MW.
And you could say “just build a lot of them” but the capacity per unit of area tends to be pretty low for these types of technologies.
Building them where we have ample space is okay. But now this power has to be transmitted, and we are already having a lot of problems with transmission line congestion as-is. The real advantage of energy storage is when it’s done local, no need for transmission lines.
Plus there’s permitting/stability issues as well. These wouldn’t work if the area was prone to earthquakes or other natural events.
From a grid stability point, you can’t produce more than is used, else you get higher frequencies and/or voltages until the automatics shut down. It’s already a somewhat frequent occurence in germany for the grid operator to shut down big solar plants during peak hours because they produce way more power than they can dump (because of low demand or the infrastructure limiting transfer to somewhere else)
Negative prices are the grid operator encouraging more demand so it can balance out the increased production.
As someone with a technical background this is the stupidest problem with solar that I don’t get… just turn off the panels in groups until generation is closer to demand… how have engineers not figured that out. And if they have why does this still get written about.
Someone is an idiot. Maybe it’s me?
I’m adjacent to this problem, so I have a little context, but am not an expert at all.
To my knowledge, we don’t have granular control over panels. So we can shut off legs of a plant, but that’s a lot of power to be moving all at once.
Instead, prices are set to encourage commercial customers to intake more power incrementally. This has a smoother result on the grid, less chance of destabilizing.
A customer like a data center could wait to perform defragmentation or a backup or something until the price of power hits a cheap or negative number.
Well I wasn’t expecting to find THE right answer in the comments already. Kudos!
And to everyone reading through this post: If you have questions, need more explanations or want to learn more about the options that we have to “stabilize” a renewable energy system and make it long term viable, just ask!
Spot on! I hoped this comment would be higher! The main problem isn’t corps not making money, but grid stability due to unreliability of renewables.
To be fair, the original tweet is kinda shit to begin with. They’ve unnecessarily assigned monetary value to a purely engineering (physics?) problem.
But the thing is, you CAN simply turn them off at the press of a button (or an automated script) so its really a complete non issue. As long as big solar installations control systems are accessible by the grid operators, it should be fine.
If you’re spending billions to build a solar plant that has to turn off all the time during peak hours then you’re wasting your money. That seems like a fundamental issue to me, not a non-issue.
Are there any solar plants that cost a billion dollars each?
Secondly, you want to over build solar, so that you have enough capacity during off peak hours. Grid storage is obviously the better solution, but seems not widely available enough yet.
Ok, but what do you do when you’re short of power at night? Keep in mind to turn on conventional power stations it’s expensive & time consuming. Once they startup they need to stay on for a long while to be efficient & cheap.
The real solution is to store excess power in batteries. Lithium ion is too expensive to scale, Sodium ion batteries are economically & capacity viable AFAIK.
I’ve read that gravity batteries and sand batteries are ecologically sound options that work on the scale needed to support large sections of the electrical grid.
https://interestingengineering.com/innovation/two-massive-gravity-batteries-are-nearing-completion-in-the-us-and-china
https://www.bbc.com/news/science-environment-61996520
I hesitate on
That first link is for a 10MW, 8 hour battery. 10MW is on the smaller end of generators, you’d need quite a few of these to start making an impact. For example, a small gas turbine is like 50MW, a large one is over 250MW.
And you could say “just build a lot of them” but the capacity per unit of area tends to be pretty low for these types of technologies.
Building them where we have ample space is okay. But now this power has to be transmitted, and we are already having a lot of problems with transmission line congestion as-is. The real advantage of energy storage is when it’s done local, no need for transmission lines.
Plus there’s permitting/stability issues as well. These wouldn’t work if the area was prone to earthquakes or other natural events.
Thats just not what this post is about. Obviously storing is the way but until then yiu just gotta turn em off