Finland researchers install world’s first ‘sand battery that stores clean energy’

Researchers from Finland have installed the world’s first fully working “sand battery”, which can reportedly store power from renewable energy sources. 

Markku Ylönen and Tommi Erone, the developers, who spoke to the BBC, said the innovation could solve the problem of year-round supply of renewable energy such as solar and wind.

The device, which is said to use low-grade sand, is charged with heat made from electricity from solar or wind. The sand then stores the heat at around 500C, which can warm homes when the weather is colder and energy is more expensive.

Ylönen and Erone, who are also founders of Polar Night Energy, said they had been modifying the sand battery idea and had first tested its operations in the Finnish city of Tampere during the winter of 2020 to 2021.

They have now completed the first commercial installation of the sand battery in the town of Kankaanpää, and installed the device in the Vatajankoski power plant, which runs the district heating system for the area.

“Whenever there’s like this high surge of available green electricity, we want to be able to get it into the storage really quickly,” Ylönen told BBC. 

The developers believe the device can solve the problem of affordable energy, because sand is a very effective medium for storing heat and loses little over time. They said the device could keep sand at 500C for several months.

According to a statement issued by Polar Night Energy on Tuesday, Ylönen said the innovation will make a significant impact in terms of providing green energy solutions.

“This innovation is a part of the smart and green energy transition. Heat storages can significantly help to increase intermittent renewables in the electrical grid,” he was quoted as saying.

“At the same time, we can prime the waste heat to usable level to heat a city. This is a logical step towards combustion-free heat production.

“The construction of the storage went well, especially considering that the solution is completely new. We managed to get everything in order despite some challenges and a short delay. Now the sand is already hot.” 

Meanwhile, the development is believed to be good for Finland because it is coming at a time when Russia has halted its gas and electricity supplies to the country because of the former’s decision to join the North Atlantic Treaty Organisation (NATO).