Finland warms up the world’s largest sand battery, and the economics look appealing

It does not seem much, but Finland recently turned the key over the world’s largest battery.

Yes, sand.

The sand battery is a type of thermal energy storage system that uses sand or broken rocks to store heat. Electricity is used – usually from renewable sources – to heat the sand. This heat stored later on various ends can be used, including warm buildings.

Economics are convincing, and it is difficult to get any cheaper than the crushed soap stone now inside a silo in the small town of Pornainen. The soap stone was mainly – it was ignored by the Finnish fireplace maker.

Although it may not be visually impressive like a large Li -Ion battery package, 2000 metric tons of crushed rocks inside the seamlessness of 49 feet are promised to cut carbon emissions in Pornainen, which helps the city get rid of the oil that is currently helping to operate the city area heating the city area currently.

Like many Scandinavian cities, Pornainen runs a central kettle that heats water for homes and buildings throughout the city. The Polar Night Night Battery can store 1000 MW an hour of heat for weeks at one time, enough for a week of heating in the cold Finnish winter. From storage to recovery, about 10 % is lost to only 15 % of heat, and the temperature in the exit can reach 400 ° C.

The city’s heating system in the city also depends on burning wood chips, and the sand battery will reduce this consumption by about 60 %, according to Polar Night. The heat can also generate the electricity battery, although the process will sacrifice some efficiency.

Since renewable energy sources have become cheaper, interest in thermal batteries has grown. Behind the polar night, many startups follow heat batteries. Sunamp, which is based in Scotland, builds one -based seat based on the same material that gives potatoes salt and treachery its flavor. Solutions Thermal Solutions, second place in Battlefield 2023, ranked second in Techcrunch, created a kind of brick that could result from heat approaching 2000 ° C. The fourth energy is made by graphite blocks that store electricity by 2400 degrees Celsius.

Pornainen battery is charged using electricity from the network, and the enormous storage of the operator allows the power to draw when it is cheaper. Finland is mostly renewable energy sources (43 %) and nuclear (26 %), which means that electricity is very clean. It is also cheaper in Europe at less than 0.08 euros per kilowatt hour-less than half of the European Union.

Polar Night did not reveal the cost of the project, although the raw materials are cheap and the structure itself is not particularly complicated. It costs a much smaller preliminary model that was built a few years ago about $ 25 per kilowatt hour of storage, as the company was estimated at that time. The new version is likely to be cheaper. Lithium Ion batteries cost about $ 115 per kilowatt hour.