Ilmatar and Nuveen Launch 30MW Co-located BESS in Finland
—
Developer Ilmatar and investor Nuveen Infrastructure have officially commenced operations of a 30MW/41MWh Battery Energy Storage System (BESS) in northern Finland. This project, named the Ainola BESS, is integrated with the Piiparinmäki wind farm in the North Ostrobothnia region and features a storage capacity that lasts for 1.36 hours.
Ilmatar has stated that this facility is among the largest BESS in Finland directly linked to renewable energy production, indicating that it shares some grid infrastructure with the wind farm, likely through an interconnection point. Energy-Storage.News has reached out to Ilmatar for further clarification on this matter.
The BESS will engage in the wholesale electricity market, participating in both the day-ahead and intraday markets, and is currently undergoing the approval process for reserve markets. Mika Jantunen, head of technology at Ilmatar, expressed pride in the Ainola BESS, highlighting the innovative solutions and forward-thinking strategies that were essential for its development and deployment.
Ilmatar developed and constructed the project, retaining a 10% equity stake, while Nuveen Infrastructure owns the remaining 90%. Nuveen acquired the wind farm from Ilmatar in 2019, following a previous acquisition of the project by Glennmont Partners, which was subsequently absorbed into Nuveen in 2021. The BESS was co-developed by Glennmont Partners, and according to initial construction information released in 2023, the system was integrated by the Netherlands-based company Alfen.
Originally slated to be operational by the second quarter of 2024, Ilmatar recently received planning approval for additional projects in Finland, including a 50MW photovoltaic (PV) system and a 20MW BESS. The company is also collaborating with Polar Night Energy, a firm specializing in ‘Sand Battery’ technology, to develop power-to-heat-to-power applications utilizing their thermal energy storage solutions. Polar Night Energy has recently commissioned its largest project to date, which consists of a 1MW/100MWh system for district heating.
As Finland’s renewable energy generation expands, opportunities in the energy trading and ancillary service markets are also growing, driving demand for large-scale BESS installations. In 2025 alone, several large-scale projects (ranging from 30MW to 70MW) have been launched by companies such as Eco Stor AS, Ingrid Capacity, SEB Nordic Energy, NTR, Renewable Power Capital (RPC), and Ardian.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/ilmatar-and-nuveen-launch-30mw-wind-integrated-battery-energy-storage-system-in-finland/
