A small town in Finland is about to give up fossil fuels in your heating network thanks to a sand -filled energy storage tank the size of a house.
The Finnish Startup Polar Night Energy recently switched on the so -called sand battery in the municipality of Pornainen, an hour north of Helsinki.
The machine that uses dirt to store excess renewable energies as heat will heat the houses and shops in the city 5,000 people. It is expected that natural gas and oil are completely replaced in the porn navigation of District Heating Network in order to lower emissions by An estimated 70%.
“This project is a strong example of the fact that effective solutions for reducing climate change exist,” said Liisa Naskali, COO from Polar Night Energy. “Burning is not a sustainable option for the climate or the environment.”
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The energy storage structure measures about 13 meters high and 15 meters wide and is filled with 2,000 tons of crushed soap stone, a by -product of the construction industry. The new battery is 10 times larger than the first of the startup Pilot plant In PornPresent Started in 2022.
The sand battery from Polar Night contains 2000 tons crushed caterpillar. Credit: Polar Night
If there are plenty of renewable energies like on a sunny or windy day, clean electricity is wired to the battery. There it moves a heater, which sends hot air into the huge sand tax through a series of pipes and heats it to a toasted 600 ° C.
Thanks to the isolated wall of the battery, this energy can be saved for weeks or even months. If necessary, the battery loads the hot air on demand – warm water in the district heating network. This can give households, factories and even swimming pools heat.
“Of course we cannot solve the entire problem of climate change alone, but we need different solutions, and our sand battery is one of them” Naskali in A video.
With an output of 100 MWh, the polar estimates that the battery can heat the entire city of Pornainen for a week in winter or a whole month in summer if demand is lower – at just one fee. The city is still retained a biomass kettle that burns wood chips as a backup source during the peak requirement.
Loading the sand battery from ambient temperature to 600 ° C takes about four days. In practice, however, it has continuously risen with excess renewable energies when it is available – so it rarely falls back to the temperature of the surrounding air.
The insulation plates on the outside of the sand battery help to keep the heat longer. Credit: Polar Night
Polar Night said it is currently discussing the installation of new, larger sand batteries in Finland and internationally. The aim is to offer a cleaner alternative to fossil fuels for heating houses.
After International energy agency (IEA)The heating accounts for about half of the total energy consumption. In Europe, the majority of this heat comes from combustion Natural gas, oil, wood chips or waste.
For European cities, especially those with access too much renewable energies, sand batteries could be lowAFruits Ningen. If you are scaled, you could be an integral part of the Energy Storage Toolbox in addition to other options such as lithium ionPresent GravityPresent HydropowerPresent And CO2 domes.
