FINLAND - Finnish companies have built the world's first operational "sand battery".

Dezeen has announced that Finnish companies Polar Night Energy and Vatajankoski have built the world's first operational "sand battery", which provides a low-cost and low-emissions way to store renewable energy. The battery, which stores heat within a tank of sand, is installed at energy company Vatajankoski's power plant in the town of Kankaanpää, where it is plugged into the local district heating network, servicing around 10,000 people.

According to Dezeen, the company behind the technology says that it helps to solve one of the key obstacles in the transition to full renewable energy: how to store it for use during times when the sun isn't shining or wind isn't blowing, and particularly for use in the wintertime when demand is high.

According to the company, Polar Night Energy's sand battery stores heat for use weeks or even months later. It works by converting the captured renewable electricity into hot air by using an industrial version of a standard resistive heating element, then directing the hot air into the sand. The heat transfers from the air to the sand, which ends up at temperatures of around 500 to 600 degrees Celsius and retains that heat well. To unlock it for use, the process is reversed, and the hot air is funneled into a heating system used for homes or industry.

Source: Dezeen