Merus Power will deliver a €17 million energy storage system for Exilion
Finnish companies Merus Power and Exilion have signed an agreement to build an energy storage system with parameters of 30 MW / 66 MWh. The contract is valued at approximately EUR 17 million. The installation will be constructed in Kuortti, in the municipality of Mäntyharju in eastern Finland, and its completion is planned for 2026. The project will strengthen the local energy infrastructure in the South Savo region and become one of the key investments in this part of the country.
Merus – developer and technology supplier
Merus Power serves as the main developer of the project. Thanks to its ability to deliver and commission the system quickly, the company will enable Exilion to bring significant balancing capacity to the energy market. As the manufacturer highlights, the project will use the same platform that recently powered the first grid-forming energy storage system in Scandinavia.
The technology applied will support the natural inertia of the grid and increase the stability of the power system, especially during periods of high wind and solar generation. This responds to the growing share of renewables in Finland’s energy mix and the increasing demand for regulation services. With the new BESS, operators will gain a resource capable of responding quickly to frequency fluctuations, and consumers will benefit from a more reliable grid.
Security of supply and flexibility
“We are proud and pleased with the agreement concluded with Exilion. The 30 MW / 66 MWh energy storage system is one of the largest we have developed in Finland. This project is significant not only because of its size, but also in terms of energy security, system flexibility, and the ecological transition,” says Kari Tuomala, CEO of Merus Power.
“We see energy storage as a key enabler of the renewal of the energy system and the shift towards environmentally friendly sources. The Mäntyharju project is an important step for us. We are pleased to have our long-term partner by our side – a strong and experienced Finnish technology company,” adds Tommi Riski, Director of Business Development and Electricity Markets at Exilion.
Schedule and scope of work
The contract includes the design, delivery, and commissioning of the energy storage system, as well as the implementation of control solutions necessary to provide services for the power system. Completion of the project is scheduled for 2026, which will allow new flexibility resources to be integrated into the system relatively quickly. The Kuortti site in the municipality of Mäntyharju was chosen due to the importance of eastern Finland in the development of renewable energy sources and the need for local stabilization services.
Why this matters for the region
The South Savo region is becoming an attractive location for wind and solar energy. In such conditions, energy storage systems act as buffers—storing surplus production and releasing it during periods of deficit, while also helping maintain power quality parameters. The new project will increase the grid’s resilience to disturbances and shorten response times to sudden changes in generation, improving supply reliability for end users.
The new 30 MW / 66 MWh BESS will deliver balancing and stabilization services, meeting the rapidly growing demand for flexibility in systems with high shares of renewables. Its location in eastern Finland will help support security of supply in the region and increase grid resilience during periods of high wind and solar generation. The project also confirms the competitiveness of Finnish technological expertise and strengthens Merus Power’s position in the energy storage market.