Polar Night Energy, a startup in Finland, has developed a sand battery that can store heat for many months and ensure the supply of green energy throughout the year. This device, which has been installed at the Vatajankoski Power Plant in Finland, uses a silo with thick walls that is filled with 100 tonnes of builder’s sand.
The sand is charged using low-cost solar and wind energy. Passing electricity through a non-super-conductor material like sand causes friction, generating heat. The hot air produced is circulated in the sand battery and this keeps the sand hot for many months. The battery is connected to a heating network and is used to warm offices and homes.
Did You Know?
Energy can neither be created nor destroyed; it can only be transformed.