Finnish mine to host 75 MW/530 MWh underground pumped hydro facility

The European Commission has approved €26.3 million of funding to the Finnish government, which the Ministry of Economic Affairs and Employment has awarded to Suomen Energiavarasto Oy (Sevo).

The Finnish developer will use the funds to build an underground pumped hydro storage station at a former zinc and copper mine owned by First Quantum Minerals in Finland. Mining activities will be completely shut down by the end of this year.

“The storage unit will participate in the electricity spot markets, as well as in electricity balancing markets,” the commission said in a statement. “The storage unit will effectively substitute in the grid electricity generated by high-cost gas-fired units with low-cost, clean electricity available notably during strong renewable energies generation conditions.”

Finnish energy company EPV Energy joined the project in early 2021. The pumped hydro station will have a capacity of 75 MW/530 MWh and generate between 60 GWh and 160 GWh of electricity per year. The Pyhäsalmi Mine is the deepest base metal mine in Europe, at a depth of 1,444 meters.

“This energy storage project, if implemented, would bring excellent flexibility to EPV’s future energy system,” the company said. “Several studies have already been carried out on the feasibility of the energy storage project, and EPV Energy has contributed to them by carrying out market forecasts of renewable energy and providing background information on rock engineering in collaboration with its partners.”

Sevo is developing the project under the Calilo initiative, which was launched in 2019 to oversee the redevelopment of the Pyhäsalmi Mine. According to the project’s website, the storage facility should be built in three years and its operational lifetime should at least 50 years.