Finnish company develops sand-based heat storage for batteries

Polar Night Energy and Vatajankoski, an energy utility company in Western Finland, have made a storage solution for renewable energy. The specialty of the storage is that it uses sand instead of lithium-ion or other battery technologies. The storage system has the capacity of storing electricity as heat in the sand. The company on their website said, “Polar Night Energy’s first commercial sand-based high-temperature heat storage is now in operation at Vatajankoski power plant area. The heat storage, which has a hundred tons of sand inside, is producing low emission district heating to the city of Kankaanpää in Western Finland. BBC made a story about Polar Night Energy’s heat storage solution.”


Other organizations working on sand-based heat storage


Other companies are working on the sand-based heat storage project to use sand as energy storage but as mentioned above the Finnish company is the first fully working commercial installation of a battery made from sand. NERL, a Research Laboratory of the United States that claims that they focus on creative answers to today’s energy challenges on their website said “National Renewable Energy Laboratory (NREL) are in the late stages of prototype testing a game-changing new thermal energy storage technology that uses inexpensive silica sand as a storage medium. Economic Long-Duration Electricity Storage by Using Low-Cost Thermal Energy Storage and High-Efficiency Power Cycle (ENDURING) is a reliable, cost-effective, and scalable solution that can be sited anywhere.”


According to an article by Engadget, “Similar to traditional storage systems for renewables, Polar’s technology stores energy from wind turbines and solar panels that isn’t used at once. To be precise, it stores energy as heat, which is then used for the district heating network that Vatajankoski services. Sand is inexpensive and is very effective at storing heat at about 500 to 600 degrees Celsius. Polar says its technology can keep sand “hotter than the stoves in typical saunas” for months until it’s time to use that heat during Finland’s long winters.”