Technology firm Polar Night Energy built the project for Loviisan Lämpö, at a scale ten times bigger than its previous project. Its tech works by heating a storage medium using electricity, retaining that heat and then discharging that for industrial or heating use.
“The Sand Battery means a lot to Loviisan Lämpö. It allows us to drastically reduce our emissions and improve the reliability of heat production,” said Mikko Paajanen, CEO of Loviisan Lämpö, which is owned by private equity firm CapMan Infra.
It is expected to reduce the annual annual CO₂-equivalent emissions from the local heating network, reducing climate emissions in Pornainen’s district heating by nearly 70%. It will help the network phase out the use of oil and reduce the consumption of wood chips by 60%. An existing biomass boiler will continue to serve as backup.
Heating for industry and buildings accounts for a huge portion of global emissions, but generally gets less attention than the electricity grid when it comes to decarbonisation, particularly around energy storage technology development.
Polar Night Energy’s project started construction last year. The system, pictured above, is 12 metres tall and 15 metres wide and contains 2,000 tonnes of crushed soapstone as its thermal storage medium. The soapstone comes from the manufacturing processes of heat-retaining fireplace manufacturer Tulikivi.
The project will also participate in the electricity reserve markets of Finland, with Finnish telecoms firm Elisa being enlisted to optimise this activity in January this year.
Polar Night Energy is also investing €2.1 million (US$2.2 million), an amount matched by government agency Business Finland, to test power-to-heat-to-power applications for its tech. This would mean converting the stored heat back into electricity for use in the grid.
