Finland inaugurates world’s largest 1 MW/100 MWh sand battery
Finland has inaugurated the world’s largest sand battery, a 1 MW/100 MWh thermal storage system developed by Polar Night Energy. The unit is already exceeding efficiency targets. August 28, 2025 Patrick Jowett Image: Polar Night Energy Finland has inaugurated the world’s largest sand battery this week, a 1 MW/100 MWh thermal storage system developed by Polar Night Energy. The industrial-scale unit in Pornainen began operating in June after district heating company Loviisan Lämpö commis...