The technology used to harvest clean, renewable energy from the sun and wind is rapidly advancing, and that means scientists need to figure out how to store that energy efficiently so that it can be doled out when needed.
In Finland, a team of scientists has figured out how to do just that at a relatively low cost — by building a giant battery made of sand, as detailed by Euronews Green.
Polar Night Energy, the company behind the innovation, deployed its first sand battery in 2022 in the town of Kankaanpää. Now, the company is building another sand battery that is 10 times larger than the first. It will be capable of storing 100 megawatt-hours of thermal energy and will help the residents of Pornainen, Finland, heat their homes while cutting planet overheating pollution by nearly 70%, as Euronews Green reported.
Though the most common method of storing green energy is in lithium batteries (which are found in the vast majority of electric vehicles, for example), these batteries come with a few drawbacks. Lithium has to be mined — with environmentally destructive consequences — making it expensive. It is also a non-renewable resource, and lithium batteries are much better at storing energy over short durations than long periods of time.
Sand, on the other hand, is not rare at all, meaning that sand batteries can be built with minimal expense and environmental impact.
Polar Night Energy has even found a supplier that happens to have a lot of sand lying around as a byproduct of its fireplace manufacturing business. That means that if sand-battery usage becomes widespread, it could result in cheaper, cleaner energy for everybody.
“There’s really nothing fancy there,” Markku Ylönen, one of the co-founders of Polar Night Energy, told Euronews Green. “The complex part happens on the computer; we need to know how the energy, or heat, moves inside the storage, so that we know all the time how much is available and at what rate we can discharge and charge.”
