Hyvinkään Lämpövoima has begun construction of a €33 Million thermal energy storate facility in Hyvinkää, located in the Helsinki Ring of Industry region. The facility will become the largest of its kind globally – and the first of its kind in Finland. Built into a decommissioned gravel pit, the project marks a major leap forward in renewable heat storage and positions the region as a frontrunner in climate-smart infrastructure.
The facility will hold 380,000 cubic meters of water, with a single full charge storing 18,000 MWh of energy. Over the course of a year, up to 100,000 MWh of heat will flow through the system, covering nearly a quarter of the annual heating demand in the city.
The project is expected to reduce CO₂ emissions by 4,400 tons annually and generate millions in savings. It will also support flexibility of the electricity market in tandem with electric boilers and strengthen the city’s energy self-sufficiency and the security of supply for its district heating system.
“This thermal storage is a cornerstone of future district heating system in Hyvinkää, which will rely entirely on waste heat and renewable sources. It allows us to fully utilize affordable energy from electric boilers and waste heat, ensuring stable heating prices for residents and businesses,” explains Sanna Kytömäki, CEO of Hyvinkään Lämpövoima Oy.
Construction will take approximately two years, with completion scheduled for autumn 2027. The Finnish Ministry of Economic Affairs and Employment has granted €7.7 million in funding through its major demonstration project program.
Energy Storage Is Reshaping the System
According to Professor Esa Vakkilainen, professor emeritus energy systems at LUT University, the Hyvinkää project reflects a broader transformation in energy markets. “Energy storage has moved from hours and days to full-year solutions. When heat can be transferred from Summer to Winter, fuel consumption drops and prices stabilize.”
“During Summer, electricity is cheap and abundant, but heating demand is low. If surplus heat can be stored and used during Winter, the system operates on a completely different logic. Hyvinkää’s solution is an excellent example of this,” he adds.
Vakkilainen notes that waste heat from data centers fits this pattern perfectly.
“Data centers produce heat all year round, and when this heat can be stored efficiently, we are talking about true circular economy. This is also a competitive factor: companies prefer to locate in areas where waste heat can be utilized.”
Smart Location for Energy Investments
The Helsinki Ring of Industry is no stranger to energy innovations. In Pornainen, the Sand Battery by Polar Night Energy is expected to reduce annual CO₂-equivalent emissions from the local heating network by around 160 tons, cutting the municipality’s district heating emissions by nearly 70 percent.
And let’s not forget the region’s upcoming data centers, such as those by Microsoft and Verne, and their waste heat recovery projects. In addition, Mäntsälän Biovoima by Auris Energy, which transforms organic waste into renewable energy, and in Kerava, one of Europe’s largest carbon capture facilities, Carbo Culture’s R3 plant, is under development.
These projects show how operators across the Helsinki Ring of Industry are actively shaping the future of energy – through both bold investments and agile pilots. With cost-effective plots, skilled workforce, and stable business climate, the region is ready for large-scale, forward-looking investments.
If you’re looking for space for a clean energy project, smart manufacturing, or circular economy solutions, the Helsinki Ring of Industry welcomes you!
Hyvinkään Lämpövoima
Hyvinkään Lämpövoima Oy is a service company fully owned by the City of Hyvinkää. More than 90% of its heat procurement is based on energy recovered from waste and bio-based heat sources. Local companies can benefit from the district heating and natural gas services provided by the company.
