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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

#121

Post by dguest »

myrmidon wrote: post #75
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…

> 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. This is not a valid conclusion. Battery projects like this are gonna charge/heat up when the electricity price is low, electricity price is low when supply/demand ratio is high and this often happens when renewable electricity is most available and makes up a…

I think the primary energy does include electric generation, but you're right, I posted the wrong chart. The correct one is here:

https://ourworldindata.org/grapher/electricity-prod-source-s...

and it backs up your point. Sorry to any Fins I might have offended with my lazy post.

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

#122

Post by moooo99 »

grues-dinner wrote: post #110
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…

There's also some long-term risk here. If we, humans, did massive amounts of dispatchable solar and wind, plus systems like this, static battery storage, other storage and things like widespread EV capacity arbitrage, it's not guaranteed that the negative or even low energy price events would even happen. The more people think they can store it and sell it later, the higher the demand for off-peak power. You could en…

Its of course true that this will somewhat even out once storage becomes more available. But there are still market forces at play. If the electricity prices are higher, operators have a renewed financial incentive to generate more power (more power = more revenue), for example by re-powering solar and wind farms.

Theoretically this would be an endless cycle, which is of course constrained by very practical needs of the electricity users.

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

#123

Post by grues-dinner »

flowerthoughts wrote: post #104
davedx wrote: post #81

Good idea but why is it being measured in MW/MWh when it’s not an electrical battery? I know they can be converted but maybe it should be measured in actual thermal units like Btu?

W and J are the SI units for power and energy. Those units make the most sense to use in Europe, regardless of the type of energy. Wh is an abomination that has come about because professionals think consumer brains would expose if they ever saw the unit watt-seconds (J). No consumer had any preconceived notion of either Wh or J, so had we used J from the start, it wouldn't have been a problem... (Yes, same with Ah v…

I dunno, 1kWh seems quite natural as a unit of building-scale energy usage when you know a kettle or space heater is about 3kW. We think about energy usage much more in terms of kW and hours than in watts and seconds. And even in small devices like an LED bulb, 5W is more obviously 0.005kW than, say, 2 hours is 7200 seconds.

And in this context it's much more obvious that it can notionally deliver energy at a peak rate of about 1% capacity per hour. If you said 1MW/360GJ, I don't think that would be nearly as clear.

Same for batteries, which started with car batteries/deep cycle batteries, rather than AA batteries, which usual don't even say, and phones. A battery that provides 1 amp (at 12V, but that's already given in a system) for 50 hours. Makes immediate practical sense, especially when equipment is often labelled in current draw and you can measure amps with an ammeter. 2.16MJ far less so.

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

#125

Post by alkonaut »

haspok wrote: post #111

This is not a battery, this is thermal storage. No electricity is stored or generated. (Unlike liquid-metal batteries, for example, which are actual battery storage.)

No one is claiming it is storing electricity. I think people who use imperial (BTU) units for heat but SI units for electric power some times get confused by what power really is and what a battery is.

Something that stores _energy_ is a battery. Not necessarily electric energy. You can absolutely have a battery with mechanical energy (wound up springs), a battery with kinetic energy (a weight in a shaft) a battery with nuclear energy (Thermal reactor in a satellite), a battery with thermal energy (silo full of very hot sand) or a battery with chemical energy such as a Li-ion battery.

This stores 100 MWh heat energy, so it is a battery.

From wikipedia:

> Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an accumulator or battery.

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

#126

Post by hulium »

bryanlarsen wrote: post #114
kragen wrote: post #96

Earlier quoted context omitted.

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…

Finland is the only country in the world where solar isn't the cheapest form of electricity because they get so little sun and they have good alternatives.

Certainly not the only country. Iceland is even more extreme in this regard and unlike Finland it is powered by 100% renewables, hydro and geothermal energy. In Finland the only good renewable alternative is wood/biomass.

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

#127

Post by IshKebab »

crote wrote: post #78
IshKebab wrote: post #55

Earlier quoted context omitted.

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.

Rather the opposite, actually. Air is a pretty good insulator, we wear coats to prevent air from moving around . How do most coats keep you warm? Trapped air. The London underground is hot because the ground is an okay-ish heat conductor: it carries heat away well enough that for a century it essentially acted as an unlimited heat sink, so during its initial construction they never bothered to build proper ventilatio…

> How do most coats keep you warm? Trapped air.

That is why I very specifically said open air.

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

#128

Post by IshKebab »

whimsicalism wrote: post #62
IshKebab wrote: post #55

Earlier quoted context omitted.

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

I said open air.

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

#129

Post by conception »

echelon_musk wrote: post #120
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…

What does MAGA have to do with Finland?

Authoritarian populism support is rising globally.

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

#130

Post by skrebbel »

zahlman wrote: post #112
skrebbel wrote: post #98

Earlier quoted context omitted.

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…

It has nothing to do with political partisanship (except to the extent that false-flagging happens or that powerful individuals have bad ideas about how to propagandize for their cause). Most people are just terrible at critical thinking, and most of the interesting claims (especially statistical ones) are simply not verifiable by random individuals. Plenty of leftists have their own reasons to distrust media. But sc…

Appreciate your response. I think I agree with all of it, great points.
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