SENS acquires energy storage project at former Pyhäsalmi mine in Finland

Sustainable Energy Solutions Sweden Holding AB (SENS) has acquired project companies designing energy storage at the former Pyhäsalmi mine. The acquisition includes an 85 MW Battery Energy Storage System (BESS) and a 75 MW underground Pumped Hydro Storage (UPHS) facility. This pumped storage power plant, planned for Europe’s deepest mine, would generate electricity by channeling water from the surface down through turbines to generate energy during high price periods. Conversely, during low price periods, water would be pumped back to the surface, thereby providing flexibility to the power grid.

The pumped plant will be integrated with a battery storage system larger than the 56.4 MW battery storage currently under construction in Yllikkälä, Lappeenranta, which is the largest in the Nordics by Nidec. In May, SENS reached an agreement with development company Callio Pyhäjärvi for the provision of technical solutions for the planned energy storage at the Pyhäsalmi site. The company has now acquired ownership of the project components, which are already preparation-ready for construction.

SENS is currently seeking investors, aiming to fully finance both projects in a short time frame. The BESS project is expected to be operational by 2025, leveraging price differences across markets. Funding for the underground pumped storage facility is anticipated to be secured by the end of 2024, with construction slated to begin in 2025. According to the company, a €26.3 million grant from the Ministry of Economic Affairs and Employment is available for the UPHS project. Previously, EPV Energia was preparing the pumped power plant but withdrew from the project last October due to cost estimates rising to approximately €250 million.