'A Very Finnish Thing': Huge Sand Battery Starts Storing Wind Energy In Soapstone (cleantechnica.com)
- Reference: 0179040730
- News link: https://hardware.slashdot.org/story/25/09/06/027211/a-very-finnish-thing-huge-sand-battery-starts-storing-wind-energy-in-soapstone
- Source link: https://cleantechnica.com/2025/08/30/finnish-city-inaugurates-1-mw-100-mwh-sand-battery
The battery "will enable residents to eliminate oil from their district heating network, thereby cutting emissions by nearly 70%," [2]notes EuroNews :
> Euronews Green previously spoke to the young Finnish founders, Tommi Eronen and Markku Ylönen, who engineered the technology... Lithium batteries work well for specific applications, explains Markku, but aside from their [3]environmental issues and expense, they cannot take in a huge amount of energy. Grains of sand, it turns out, are surprisingly roomy when it comes to energy storage... The sand can store heat at around 500C for several days to even months, providing a valuable store of cheaper energy during the winter... The battery's thermal energy storage capacity equates to almost one month's heat demand in summer and a one-week demand in winter in Pornainen, Polar Night Energy says...
>
> Polar Night Energy has big ambitions to take its technology worldwide, and is currently in "active discussions" with both Finnish and international partners.
This project (in the Finnish city of Pornainen) "is really important for us because now we can show that this really works," a spokesperson for Polar Night [4]told Clean Technica :
> The profitability of the sand battery is based on charging it according to electricity prices and Fingrid's reserve markets. Its large storage capacity enables balancing the electricity grid and optimizing consumption over several days or even weeks... "The Pornainen plant can be adjusted quickly and precisely," explained Jukka-Pekka Salmenkaita, vice president of AI and special projects at Elisa Industriq, "and it also has a remarkably long energy buffer, making it well suited for reserve market optimization. Our AI solution automatically identifies the best times to charge and discharge the Sand Battery and allocates flexibility capacity to the reserve products that need it most. Continuous optimization makes it a genuinely profitable investment."
Thanks to Slashdot reader [5]AleRunner for sharing the news.
[1] https://www.the-independent.com/tech/sand-battery-renewable-energy-finland-b2818348.html
[2] https://www.euronews.com/green/2025/06/15/sand-batteries-could-be-key-breakthrough-in-storing-solar-and-wind-energy-year-round
[3] https://www.euronews.com/green/2022/02/01/south-america-s-lithium-fields-reveal-the-dark-side-of-our-electric-future
[4] https://cleantechnica.com/2025/08/30/finnish-city-inaugurates-1-mw-100-mwh-sand-battery/
[5] https://www.slashdot.org/~AleRunner
Bur we can burn Fossile Fuels!! (Score:2)
Why don't you want to just convert Carbon and O2 into CO2? It seems to be more expensive now, but what the hell? It can't hurt. huh?
Heat? (Score:2)
Heat is useful in Finland's metropolitan heating systems, no doubt, but I wonder how they convert that heat into electricity, which is something a chemical battery doesn't need to do. They clearly have chosen a solution,since there are surely many...I'm just too lazy to look it up.
Re: (Score:2)
> Heat is useful in Finland's metropolitan heating systems, no doubt, but I wonder how they convert that heat into electricity, which is something a chemical battery doesn't need to do. They clearly have chosen a solution,since there are surely many...I'm just too lazy to look it up.
I RTFA, and I'm pretty sure that they don't convert the heat back to electricity. I think that they use it for home heating - including hot water for showers, laundry, etc. - and to provide some heat for industry.
If I'm correct, the "optimizing consumption over several days or even weeks" is entirely about converting electricity to heat when supply is high and demand is otherwise low, allowing the stored heat to be used directly as needed rather than converting it back into electricity.
So it works in a cold
Use in warmer climates (Score:2)
Hot water always has at least a little demand, but with heat pump systems, they could use excess power to produce cold water, to be used for cooling during high demand periods.
Basically, imagine if for my house I had a X gallon insulated water tank. Rather than heating it, it's cooled using a heat pump when power is cheap and temperatures lower, such as at night, making the cooling more energy efficient.
Then, during the day, rather than going through the high-power compressor for the cooling and the conden
Re: (Score:2)
They don't produce electricity, this is a heating solution.
They keep and use what the Sun sent in last summer instead of burning the solar energy stored as gas hundreds of millions of years ago.
Finnish? (Score:2)
Really. Rofl.
Re: Finnish? (Score:2)
Oh, because of saunas? (pronounced sa-ow-na, btw, not saw-na).
Facts behind it (Score:2)
So I read the actual source, rather than all the silly editorials.
[1]https://www.loviisanlampo.fi/b... [loviisanlampo.fi]
Then I followed up on some of the links in it leading to relevant companies.
It's basically a sponsored grade local thing that seems to be done mostly for PR/environmental credits/environmental promises reasons for participants. 1MW hypothetical output, 100MWh potential storage. Thermal only, intended for remote heating. Blog breaks down project sponsors as follows:
Municipal government has their own net zero pr
[1] https://www.loviisanlampo.fi/blogi/loviisan-lampo-invests-in-polar-night-energys-sand-battery-in-pornainen---towards-non-combustion-heat-production
Re: (Score:2)
> (i.e.you just add an additional circuit in a typical power plant, where some of the steam is directed into a separate heat exchanger to heat remote heating circuit contents of which are then pumped across remote heating network).
Depending on how the heating system is set up, typically the steam is used for heating AFTER passing through the turbine. Basically, rather than going through a condensor that puts the heat into the air or a water source like a river, or even evaporating water, like nuclear power plant cooling towers, it's used for district heating.
High grade dry steam is used for electricity generation, low grade wet steam for district heating. Done that way, it's practically free except for the infrastructure to utilize
It rings a bell... (Score:2)
If I recall correctly, I read that London's "Big Ben" bell took an entire month to cool off after forging it.