Developer Merus Power has delivered and commissioned a 38MW/43MWh battery energy storage system (BESS) in Lappeenranta, Finland.
The BESS is jointly owned by a partnership between Ardian’s Clean Energy Evergreen Fund (ACEEF), a private equity firm, and the local energy company Lappeenrannan Energia.
Merus says it is the company’s largest BESS manufactured and one of the largest BESS facilities in use on the Finnish electricity market.
The BESS is located in the Mertaniemi area of Lappeenranta and is integrated into the regional energy system.
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Ardian enlisted Merus for the project in 2024.
At that time, Merus reported its ‘share of the investment’ in the project as €15 million (US$16 million at the time), covering delivery, testing, and commissioning of the BESS. The overall investment is higher, encompassing locally built infrastructure and a long-term maintenance contract, which is also provided by Merus.
In an in-person interview at the Energy Storage Summit EU 2024 in London last year, Merus’ sales director Markus Ovaskainen and eNordic’s investment and M&A director Aleksi Lumijärvi discussed the project’s timing, grid-forming capabilities, and the decision to use a 1-hour duration.
Regarding the project’s grid-forming capabilities in particular, Ovaskainen said:
“This is a new regulation that has come in only very recently in Finland by the Finnish TSO Fingrid, and it’s now valid for systems of this size. It will be one of the first to support the grid in this way.”
“It is partially about artificial inertia, but ultimately it’s about how the system must react to sudden electrical phenomena in the network so that it reacts in a similar way to turbine-based generation. In Finland, there is a big pipeline of wind and power, and the TSO is worried about the inertia and a lot of power electronic interfaced generation in the grid. So energy storage requirements are getting stricter so that it supports the grid in all situations.”
Notably, the project was completed in 18 months, which Benjamin Kennedy, Managing Director Infrastructure – Renewables, Ardian, highlighted, saying:
“The completion of Mertaniemi is a major milestone for us, representing the Ardian Clean Energy Fund’s first investment in battery energy storage in Finland. As the country’s wind power capacity continues to grow, the demand for storage solutions has only increased, making this asset critical to maintaining the stability of the grid and providing greater reliability.”
“We are proud to have brought this solution online within 18 months, and we see significant opportunity to invest in battery storage in the Nordics, where we plan to continue building out our platform.”
