World’s largest Sand Battery now in operation in Finland
The Sand Battery, developed by Finnish company Polar Night Energy, is a high-temperature thermal energy storage system that stores clean and affordable electricity as heat in sand or similar solid materials.
Finnish company Polar Night Energy has built an industrial-scale Sand Battery in Pornainen for Loviisan Lämpö’s district heating network. The new Sand Battery delivers 1 MW of thermal power and offers a storage capacity of 100 MWh, making it ten times larger than the Sand Battery launched in Kankaanpää in 2022.
The Sand Battery is a high-temperature thermal energy storage system that stores clean and affordable electricity as heat in sand or similar solid materials. It can be used to produce heat for both district heating networks and a wide range of industrial processes.
“The Sand Battery…allows us to drastically reduce our emissions and improve the reliability of heat production,” said Mikko Paajanen, CEO of Loviisan Lämpö.
The Sand Battery is expected to reduce annual CO₂-equivalent emissions from the local heating network by around 160 tons, cutting climate emissions in Pornainen’s district heating by nearly 70 percent, according to a media release.
With the launch of the Sand Battery, the use of oil in the Pornainen’s heating network will be completely phased out, and the consumption of wood chips will decrease by approximately 60 percent. The existing biomass boiler will continue to serve as a backup and will support the Sand Battery during peak demand periods.
“Combustion is not a sustainable option for the climate or the environment. This project is a powerful example, that effective solutions for mitigating climate change do exist,” said Liisa Naskali, Chief Operating Officer of Polar Night Energy. “Loviisan Lämpö is a great example of a company bold enough to invest in new technologies.”
Polar Night Energy acted as the main contractor for the project and delivered the Sand Battery as a turnkey solution to Loviisan Lämpö. The construction took about a year and involved around 40 subcontractors and over 100 workers, the media release said.
The Sand Battery stands about 13 meters tall and 15 meters wide, and it uses approximately 2,000 tonnes of crushed soapstone as its thermal storage medium. In summer, the Sand Battery can cover almost a month’s heat demand in Pornainen, and in winter, close to a week. The project received energy aid for new technology from Business Finland.
Loviisan Lämpö is owned by CapMan Infra, a fund managed by the private equity firm CapMan.
“From an investor’s perspective, this technology holds tremendous potential: it can participate in electricity reserve markets, reduce dependency on single energy sources in heat production, and serves as a great example of sector integration between electricity and heat,” said Sauli Antila, Investment Director at CapMan Infra.
