Developers SENS and Callio have revealed a hybrid project in Finland which could combine a battery energy storage system (BESS), pumped hydro energy storage and solar PV technology.
The companies have struck a principal agreement to develop the project at the decommissioned Pyhäsalmi mine in Pyhäjärvi, central Finland.
The location will allow the project to utilise existing grid infrastructure and integrate with the nearby Callio Business and Olcconen Green Industrial parks, SENS (Sustainable Energy Solutions Sweden Holding) said.
SENS is primarily a BESS project developer active mostly in Sweden while Callio is owned by the Pyhäjärvi Municipality.
Enjoy 12 months of exclusive analysis
- Regular insight and analysis of the industry’s biggest developments
- In-depth interviews with the industry’s leading figures
- Annual digital subscription to the PV Tech Power journal
- Discounts on Solar Media’s portfolio of events, in-person and virtual
Or continue reading this article for free
The BESS portion of the project is designed for a power output of 85MW and is already at the ready-to-build (RTB) stage, with commercial operation expected in 2025. It will provide frequency response services and participate in the energy arbitrage market, SENS said.
The pumped hydro energy storage (PHES) unit would be a 75MW/530MWh, 7-hour system built underground though a timeline for its development, construction or operation was not provided. The third stage of the project is a solar PV plant but details on size or timeline were not provided either.
The Pyhäsalmi mine is the deepest metal mine in Europe at 1,444 metres deep and its underground mine operation and copper and zinc processing ended in 2022, although some above-ground refining is set to continue until 2025. The underground mine is currently in the closure and decommissioning stage. It is owned by Canadian company First Quantum Minerals.
Financing for the project will be shared between SENS, Callio, the Calllio Business and Olcconon business and industrial parks, UB Corporate Finance and the Finnish government via €26.3 million (US$28.5 million) in subsidies for foreign direct investments (FDI) in renewable energy.
Axpo, a Switzerland-headquartered independent power producer (IPP) and energy trading firm, has also launched projects in neighbouring Sweden, commissioning a 20MW project in February which was acquired from SENS. A month prior SENS secured the land for another 40MW BESS project.
Sweden and Finland are leading BESS deployments in the Nordic region largely off the back of a lucrative ancillary services market.
