Finnish City Unveils 1 Megawatt, 100 Megawatt-hour Sand Battery for Inauguration
In the heart of Finland, a groundbreaking energy storage solution is making waves. Polar Night Energy, a company founded by Markku Ylönen and Tommi Eronen, is leading the charge with their innovative sand battery technology.
Three years ago, Polar Night Energy unveiled a prototype of their sand battery in the town of Kankaanpää. Since then, the company has been in active negotiations for several large-scale thermal storage projects, including district heating, hot air, and process steam production.
The larger sand battery, now operational in the city of Pornainen, is a 42-foot tall, 50-foot wide steel cylinder filled with 2,000 tons of crushed stone. This colossal structure is expected to reduce carbon emissions from district heating by an impressive 70 percent.
The Pornainen project serves as a critical proof point for Polar Night. Liisa Naskali, Polar Night's COO, believes that industrial applications are particularly promising, especially where heat above 100°C is required.
The sand battery works by using excess renewable electricity to heat up the crushed stone, which is stored until needed. When demand for heat increases, the heat is released, travelling through a system of pipes filled with hot water to other buildings.
Sauli Antila, the investment director at CapMan Infra, sees the sand battery as a cost-efficient and sustainable investment. Jukka-Pekka Salmenkaita, vice president of AI and special projects at Elisa Industriq, explains that the Pornainen plant can be adjusted quickly and precisely, and has a long energy buffer.
The profitability of the sand battery is based on charging it according to electricity prices and Fingrid's reserve markets. Polar Night is in talks with district heating companies and factory owners for potential sand battery projects, with Loviisan Lämpö, a Finnish district heating company, already collaborating with Polar Night on a larger sand battery.
Looking to the future, Polar Night Energy plans to construct an electricity production pilot in Valkeakoski, Finland, in the coming weeks. This project could further solidify the sand battery's position as a versatile and sustainable energy storage solution.
With its impressive round trip efficiency of 90 percent in operation, the sand battery is poised to make a significant impact on Finland's energy landscape and potentially beyond. As the world continues to grapple with the challenges of renewable energy storage, the sand battery concept offers a promising solution.
