Sand Battery: Finland’s Fossil Fuel-Free Heat
Pornainen, Finland, pioneers a groundbreaking solution: a sand battery designed to slash emissions by 70% adn ditch fossil fuels for heating. This innovative project,spearheaded by Polar Night Energy,harnesses excess renewable energy,storing it in a 2,000-metric-ton structure. The system heats crushed soapstone to 600°C, releasing heat to warm the town’s homes and businesses. This technology showcases a commitment to enduring heating solutions, offering an efficient and clean option. With a massive 100 MWh output, the sand battery marks a pivotal step toward a green future in Finland. News Directory 3 follows energy developments closely. Discover what’s next for this revolutionary energy storage system.
Finland Town Warms Up with Massive Sand Battery for Renewable Energy
Updated June 11, 2025
The town of Pornainen, Finland, is set to revolutionize its heating network by integrating a large sand battery for energy storage.This initiative, spearheaded by Finnish startup Polar Night Energy, aims to eliminate fossil fuels from the town’s heating system.
Located an hour north of helsinki,Pornainen,with its 5,000 residents,will now have its homes and businesses heated by this innovative system. The sand battery, utilizing excess renewable energy, is projected to slash the town’s emissions by an estimated 70%, marking a significant step toward lasting energy.
The energy storage structure, standing 13 meters tall and 15 meters wide, contains 2,000 metric tons of crushed soapstone. This new sand battery dwarfs Polar Night Energy’s initial pilot project launched in Pornainen in 2022.
The sand battery works by channeling clean electricity, generated from renewable sources, to heat the sand to 600°C. The insulated structure allows the energy to be stored efficiently for extended periods. When heat is needed,the battery discharges hot air to warm water in the district heating network,providing warmth to homes,factories,and even swimming pools.
“This project is a powerful example that effective solutions for mitigating climate change do exist,” said Liisa Naskali, COO at Polar Night Energy. “Combustion is not a sustainable option for the climate or the habitat.”
With a 100 MWh power output, Polar Night Energy estimates that a single charge can heat Pornainen for a week during winter or a month during summer. A biomass boiler will remain as a backup energy source during peak demand.
While charging the sand battery to 600°C takes approximately four days, the system is continuously replenished with excess renewable energy, maintaining a consistent temperature.
“Of course, we alone cannot solve the whole problem of climate change, but we need different solutions, and our sand battery is one of them,” Naskali said.
What’s next
polar Night Energy is exploring opportunities to install larger sand batteries both in Finland and internationally, aiming to provide a cleaner alternative to fossil fuels for heating.