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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

#61

Post by privatelypublic »

stavros wrote: post #49
privatelypublic wrote: post #38

Earlier quoted context omitted.

Also to add some practicals: you can drive a steam turbine with the concrete temps, but not with the water. Also, looking at how hot water could theoretically get (decomposes between 2200-3300C), it looks like 1200C is an interesting limit. Above that and you get safety(practical) and cost issues with every material I could find (common salts, pure elements). Sand just makes sense! Though, don't ever youtube sand bat…

Why not YouTube sand battery? I did it, and nothing much happened.

Previously it was a bunch of overunity nutjobs.

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

#62

Post by whimsicalism »

IshKebab wrote: post #55
whimsicalism wrote: post #26

Earlier quoted context omitted.

presumably you need the insulation from the air, otherwise it would just sort of dissipate through the ground

Open air is not a good insulator; that's why we wear coats! In contrast the ground is actually a pretty good insulator - that's why the London underground is so hot; the heat is all stuck in the ground. It'll just be cheaper to build it on the ground than to dig a big hole and then build it in the hole.

i don’t really know what to say, i wasn’t suggesting that the ground is very conductive of heat - but it is certainly much more conductive than the air is. just search.

the reason we wear coats has more to do with convection than the heat conduction of air

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

#63

Post by sfn42 »

trhway wrote: post #57
killingtime74 wrote: post #40

Earlier quoted context omitted.

Interestingly that's also about the pressure of gas in scuba tanks. Can't imagine how much energy to pressurize water to that

Due to incompressibility of liquids, pressurizing a liquid is very cheap energy-wise - orders of magnitude cheaper than pressurizing a gas. The issue is that pressurized liquid also requires correspondingly strong and expensive vessels and pipes.

You don't need to pressurize it. You just put it in a tank and apply heat, the water evaporates and creates pressure. Like a pressure cooker.

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

#64

Post by yurishimo »

looofooo0 wrote: post #45
kitd wrote: post #12

I like these technologies. They may not be as energy efficient as using more exotic materials, but what they do use is simple, cheap and often sourced locally. Such economic factors are often as important to the ROI as the purely scientific ones.

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.

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

#65

Post by testdelacc1 »

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,…

I really like this comment. Concisely explains the points of view on an investment like this. There’s not much more to add.

This is why I open the comments before the link.

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

#66

Post by dguest »

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 and wind power.

[1]: https://ourworldindata.org/grapher/energy-consumption-by-sou...

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

#67

Post by pintxo »

diggan wrote: post #37
pintxo wrote: post #31

Really like the idea, but my house alone has roughly 16 MWh/a heat consumption. Of which half gets consumed November through January. So this system could supply 12 houses? Shows the importance of proper insulation, which is still on our todo list.

Sweden seems to have some of the highest "Electricity consumption per dwelling" ( https://www.odyssee-mure.eu/publications/efficiency-by-secto... ) in Europe, and sits at 10 MWh, which makes sense, it's a very cold country but with very well isolated houses in general :) It sounds to me like you're likely an outlier here, for curiosities sake, where do you live?

Germany, and these are numbers from our gas heater. But the house is almost 50 years old and not insulated to current standards (yet).

We got a heatpump this year, going to be interesting to see how this changes things.

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

#68

Post by Avamander »

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

It's partially that, other part is that we aren't really pricing in all the externalities of everything out there. So it's not that "there's no ROI", it's that "we aren't factoring things in the ROI calculation".

So while a heat battery might not make a huge profit, the ability to burn less fuel (less air pollution, less waste, etc), to offer redundancy and stability, the know-how and work it creates, that is all valuable as well.

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

#69

Post by Hikikomori »

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…

Most of that is not for generating electricity as it includes transport and heat. Direct heating of homes traditionally used oil, wood and pellets, same as other Nordic countries. This is slowly being replaced with heat pumps that mainly use electricity from wind, water, nuclear or solar (not so much solar in Finland though).

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

#70

Post by lupusreal »

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 also reasonably fair, even if it turns out to be wrong.

And what does such cynicism have to do with "MAGA"? That asserted association seems much worse than the initial cynical assertion.

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