The purpose of the Sand Battery is to reduce carbon dioxide emissions of the district heating production in the Pornainen municipality and introduce a new flexible heat production technology.
"Loviisan Lämpö is moving towards more environmentally friendly energy production. With the Sand Battery, we can significantly reduce energy produced by combustion and completely eliminate the use of oil," says Mikko Paajanen, CEO of Loviisan Lämpö.
The impact of the investment on total emissions is approximately 160 tons of carbon dioxide equivalent per year, translating to nearly a 70% reduction in emissions from the district heating network of Pornainen. In addition to eliminating the usage of oil, the combustion of woodchips is expected to decrease by around 60%.
The municipality of Pornainen is enthusiastic about the new heating method, aligning with its goal of "Towards a Carbon-Neutral Pornainen." Many of the municipality's own buildings, including the Comprehensive School, town hall, and library, rely on district heating.
"Our municipality welcomes all innovative development projects that reduce emissions in district heating operations and contribute to network expansion," says Antti Kuusela, Mayor of Pornainen.
The Sand Battery is flexible in both its electricity usage and district heating production. It is charged from the electric grid using charging algorithms developed by Polar Night Energy, minimizing the cost of electricity used for charging while meeting the heat demand of the district heating network. The thermal energy storage capacity corresponds to almost one-month heat demand in summer and a one-week demand in winter in Pornainen.
"We want to enable the growth of renewable energy. The Sand Battery is designed to participate in all Fingrid's reserve and balancing power markets. It helps to keep the electricity grid balanced as the share of wind and solar energy in the grid increases," says Paajanen.
Loviisan Lämpö is owned by CapMan Infra fund, a part of the investment company CapMan. CapMan's vision is to be the most responsible private assets investor in the Nordics, committed to creating a sustainable future by addressing climate challenges and utilizing resources efficiently.
Polar Night Energy will deliver the Sand Battery to Loviisan Lämpö as a turnkey project. The Sand Battery will be approximately 13 meters high and 15 meters wide. The estimated duration for construction and testing is around 13 months. The project has received support from Business Finland's new technology energy aid.
"It's exciting to build a large-scale thermal energy storage, which will also act as a primary production plant in Pornainen's district heating network. This is a significant step in scaling up the Sand Battery technology," says Liisa Naskali, COO at Polar Night Energy.
Loviisan Lämpö's new thermal energy storage will use crushed soapstone produced as a byproduct of Tulikivi's manufacturing process. Tulikivi is the market leader in heat retaining fireplaces in the world.
Sand Batteries can use sand or sand-like materials as the storage material. Soapstone conducts heat better than conventional sand. According to research conducted by Polar Night Energy and Tulikivi, soapstone is an excellent choice for Loviisan Lämpö’s Sand Battery due to its unique properties.
"We always choose the thermal energy storage medium based on the customer's needs. Examining and testing different materials is crucial for us to use materials that are suitable in terms of properties, cost-effectiveness, and promotion of circular economy," says Naskali and adds, "Tulikivi is a well-known and traditional company. The soapstone they use is a very Finnish thing. It's great to collaborate with Tulikivi."
