Largest battery developed within Nordic countries commissioned in Järvenpää, Finland

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As part of Fortum’s Batcave battery project, the lithium-ion battery storage system was installed in partnership with Fortum’s biomass-powered plant in Järvenpää. Credit: Fortum
The Batcave battery’s nominal output stands at 2MW, while the energy capacity is tabbed at 1MWh. Credit: Fortum

The largest battery ever developed within the Nordic countries has been commissioned at Fortum’s Järvenpää power plant in Finland.

As part of Fortum’s Batcave battery project, the lithium-ion battery storage system was installed in partnership with Fortum’s biomass-powered plant in Järvenpää.

The Batcave battery’s nominal output stands at 2MW, while the energy capacity is tabbed at 1MWh. The battery consists of approximately 6,600 lithium-ion cells, and it offers quick grid flexibility in frequency regulation.

Tatu Kulla, head of business development at Fortum, said: “Our Batcave project takes us a big step closer towards the solar economy, where electricity storage plays an important role alongside renewable energy production forms. The electricity battery brings flexibility to the national electricity market, benefitting all electricity users. In addition to storing electricity, the Batcave project allows us to test completely new ideas for optimal control of the battery together with other flexible electricity production forms.”

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The investment cost for the Batcave development project was listed at EUR 1.6 million, for which Fortum will gain a 30% energy investment subsidy from the Ministry of Economic Affairs and Employment. The electricity battery was supplied by French company SAFT, which has decades of experience in manufacturing various battery technologies.

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