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Finnish City Inaugurates 1 MW/100 MWh Sand Battery

cleantechnica.com

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Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#91

Post by grues-dinner »

yurishimo wrote: post #64
looofooo0 wrote: post #45

Earlier quoted context omitted.

I think with enough renewable in the grid, there will always be times when the costs are 0 or negative, so you can help stabilize the grid by consuming.

Are there downsides to "just" sending all of the extra energy to ground? I've often wondered why overpowering the grid has been talked about as this huge unsolvable problem. I understand it's wasteful, of course, but waste in a ecosystem of vast abundance seems like a feature, not a bug.

> but waste in a ecosystem of vast abundance seems like a feature, not a bug.

The problem is that it's not a ecosystem of vast abundance, just occasional abundance. Literally no-one in the world right now is sitting on a constant supply of TWs of excess electrical power and saying "golly gee what are we going to do with all this". Perhaps France got closest in history and their prices still aren't "too cheap to meter".

You can "waste" the power (either by actually "burning" it to heat and dumping it, or just disconnecting the solar panels), but then you'll be short of power later and need to fall back on something expensive or with high externalities. It's also bad in terms of the capex for the solar panels (assuming solar), as you can't use your expensive plant as much as you want. If you can you'd rather use "$10" of energy that you can't sell to store and sell it later, even as heat, at any price than just lose it all.

Even if you massively, massively overbuilt solar and wind so that you were in a "vast abundance" scenario on average, you still have to store some of it for night and/or winter.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#92

Post by mzl »

dguest wrote: post #66

Finland is still 25% oil for electric generation [1] (and almost 40% fossil fuel). That means a lot of the electricity to heat the sand still comes from oil. It makes me wonder if this is more efficient than just using oil heating. Or some hybrid approach that uses oil to heat the sand. Of course there are other benefits: it's still a good way to level electric generation, which is important for e.g. nuclear plants a…

The point of these types of systems is that you can store energy when it is cheap to do so (there is an abundance of wind and/or solar energy) and use it later.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#93

Post by blueflow »

lupusreal wrote: post #70
arowthway wrote: post #50

This is super cool but the ending is bizarre. > A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days. Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric…

> And I understand that debunking low-effort accusations is asymmetric warfare Is the comment even that unfair? Asserting that it will never pay off because the presentation avoided mentioning anything about the payoff might be a little bit cynical, but not terribly so. It could be fairly presumed that if the project is a clear economic win, they would be proudly bragging about it; and the opposite presumption is als…

> And what does such cynicism have to do with "MAGA"?

"Everyone i don't like is Hitler". It's a rather immature way of disagreeing.

There is a KYM page about this phenomenon: https://knowyourmeme.com/memes/everyone-i-dont-like-is-hitle...

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#94

Post by kragen »

lupusreal wrote: post #84
yurishimo wrote: post #64

Earlier quoted context omitted.

Are there downsides to "just" sending all of the extra energy to ground? I've often wondered why overpowering the grid has been talked about as this huge unsolvable problem. I understand it's wasteful, of course, but waste in a ecosystem of vast abundance seems like a feature, not a bug.

As I understand it, you need to limit the current flow to ground to not create a fault that burns out the whole setup. The most practical way to do that is with a bank of resistors. At that point, the resistors are doing the work and you're just using the ground as a return path, which isn't necessary.

To clarify, the current flow never goes to ground; it goes back to where it started, which is why we call it a "circuit". When you do it without routing it through a load like a bank of resistors, it's called a "short circuit". Electromechanical generators will generally tend to catch on fire if you short-circuit them.

Solar panels have no problem with being short circuited; the amount of heat they produce in that state is the same as any other black object in sunlight.

Windmills are like any other electromechanical generator in this sense. You have to stop them with a brake. But that is totally a thing you can do, and quickly, and every mainstream windmill does it regularly (if only to handle overspeed winds safely), although, when this system fails, you get spectacular viral video content.

In the usual case where it works, though, you don't need a load bank either.

Load banks come into play when conventional inflexible baseload generators can't ramp down fast enough or when perverse market incentives pay renewables operators to pump power into the grid when it's not being demanded.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#95

Post by Sharlin »

csomar wrote: post #90
arowthway wrote: post #50

This is super cool but the ending is bizarre. > A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days. Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric…

The battery (am assuming it's just sand and metal) should be very cheap compared to Lithium especially in the places where you generated solar energy (they are hot and have a lot of sand). The problem is: is it profitable to even store energy there? There is no mention beyond "In operation, the sand battery has demonstrated a round trip efficiency of 90 percent.". That doesn't mean much if you do not compare it to Li…

It's right in the title. 1 MW/100 MWh.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#96

Post by kragen »

arowthway wrote: post #50

This is super cool but the ending is bizarre. > A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days. Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric…

If, say, further insulating your house or building a sand battery will pay for itself in 50 years, it's a bad investment, financially speaking, and probably environmentally speaking as well. You can deploy "the same amount" of resources in something else with a higher ROI, like maybe solar panels with a one-year payback, and get a much bigger benefit. This is an important consideration as long as you are constrained by some kind of resource limitation.

So I think ROI is a first-order consideration.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#97

Post by kragen »

csomar wrote: post #90
arowthway wrote: post #50

This is super cool but the ending is bizarre. > A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days. Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric…

The battery (am assuming it's just sand and metal) should be very cheap compared to Lithium especially in the places where you generated solar energy (they are hot and have a lot of sand). The problem is: is it profitable to even store energy there? There is no mention beyond "In operation, the sand battery has demonstrated a round trip efficiency of 90 percent.". That doesn't mean much if you do not compare it to Li…

1 MW is enough to heat somewhere between 100 and 2000 houses, depending on other factors like insulation, climate, and house size.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#98

Post by skrebbel »

arowthway wrote: post #50

This is super cool but the ending is bizarre. > A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days. Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric…

Does anyone understand why people do this? I mean, really why? It's similar to eg climate protestors quoting all kinds of outrageously incorrect statistics as fact, or saying that $TECH can supply "4% of all households" with electricity, fully knowing that households only consume a tiny % of total energy, and so on.

I simply don't get it! The political landscape across the west is that there's swaths of people who've simply stopped believing mainstream media when they're reporting things, and somehow our reaction is to just lie even more? Try to out-lie camp Trump? I mean I don't think it's even possible to lie more than Trump so wouldn't the honest, nuanced truth be a a much better antidote than global left's current strategy of "also lie, but a bit less"?

I simply don't understand where it comes from. Like in what bizarro world is this shit a smart strategy? Is it all just incompetence?

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#99

Post by kragen »

ta1243 wrote: post #58
arowthway wrote: post #50

This is super cool but the ending is bizarre. > A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days. Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric…

People nowadays expect 10% return on their investment, so if you invest 1m you need to make 100k a year from it (120k to cover the deprecation over 50 years) If you made 30k a year for 50 years you'd return 1.5m from your 1m investment, but you're only making 3%, which is a low return especially given the future risk (you'd have to run for 33 years just to get your initial investment back) Either way it's worthwhile,…

> Majority of people and countries in the world do not deem ROI to be the sole or even primary driver for investment

I think this is a little unfair. If it were true, it would be the reason for wealth inequality: you're saying that the majority of people and countries are so financially irresponsible that they consume any resources they get without investing any. But in fact everyone I have observed closely, in every socioeconomic group, tries to optimize ROI. Most of them aren't very good at it, but they do try.

On the other hand, people who expect a 10% risk-free return are just going to get scammed. There are 10% opportunities in most people's lives—weatherstripping, coupon clipping, bulk food buying, etc.—but you can run out pretty quickly.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#100

Post by Sharlin »

jnsaff2 wrote: post #35
napoleoncomplex wrote: post #10

For anyone interested in a breakdown of the basic logic, this recent blogpost that trended on HN is probably the best: https://austinvernon.site/blog/standardthermal.html Really interested in seeing how it fares in reality, almost sounds too good to be true.

Why too good to be true? There are significant trade-offs with this technology. It's storing heat, so if you need electricity then you eat a lot of efficiency. I think Vernon said ~45% round trip efficiency. Batteries are 90%+. The storage is at a high temperature (500-600C) which means that you can't use heat-pumps to produce the heat to be stored. This means that you miss out on ~400% energy gains possible from con…

The whole point is that the thermal energy is used directly, via district heating. These are not meant to store energy for electricity production (though they could do that if really needed – emergency power for various facilities? Maybe not worth it compared to diesel.)

Heat from existing thermal power plants can be stored directly and later distributed with no conversion loss; excess electricity from renewables can be turned to heat at 100% efficiency, but the problem is that peak heat demand and peak electricity supply do not typically coincide. Heat batteries are meant to solve that problem.

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