An entire town in Finland could very well get a lot of its heat from a giant sand battery before too long. The new battery has officially been announced and will be built by Polar Night Energy. It’s a really clever concept that will essentially just be made up of a massive silo filled to the brim with tons of sand or a similar material. The idea here is to pump excess energy generated during a spike from renewable energy sources and then transfer it into the sand using a heat exchange.
Extra energy generated by renewable sources like wind turbines can be turned into heat and stored in sand batteries for months at a time. Polar Night says that these amounts equate to one week’s worth of heat in Pornainen during the winter or a month’s worth of it during the summer. The battery is expected to be roughly 13 meters tall and 15 meters wide. That’s a pretty manageable size considering how much electricity it will be able to store for long periods of time without much loss.