Almere, 6 March 2025 – Alfen will deliver a 20MW/40MWh battery energy storage system (BESS) for E-Connection, co-located with a wind hub and a private 150kV grid at the coast of Neeltje Jans in the southwest of the Netherlands. The “EOS Volans” project adds to Alfen’s growing portfolio of large-scale battery systems that are helping to maximise the use of wind energy and keep the electricity grid stable. It’s expected to be operational in the first quarter of 2026.  

Signed in February 2025, the battery system will be placed on a unique location in the province of Zeeland: the artificial Dutch island Neeltje Jans at a private onshore wind hub that connects six wind farms.  

The two-hour system, in which a battery system can discharge its full capacity within two hours under a constant load, will support energy trading and grid services, including frequency regulation and reactive power, allowing the operator to optimally use wind power while providing critical flexibility to the Dutch electricity grid. 

“We are proud to build a battery system at such a unique and iconic Dutch location, where our state-of-the-art technology enhances regional sustainability and respects the dynamics of the coastal landscape,” said Stephanie Schockaert, Commercial Director for Alfen’s Energy Storage Systems business line. “The system allows the operator to optimally use wind power while providing critical flexibility to the Dutch electricity grid. The process with E-Connection and its advisor, Enerzien, has been nothing but constructive and pleasant, and we expect to see the system’s inauguration in less than a year.”  

Engineered for extreme coastal conditions 

This project is designed for durability in a high-corrosion environment with continuous exposure to salt air. Based on Alfen’s latest containerised energy storage solution, the system will feature higher grade coatings, enhanced filters, extra sealing and corrosion resistant materials with additional maintenance activities taken into account to ensure long term performance in harsh coastal conditions.  

A key feature of the Alfen system is “Island Mode”, which temporarily allows it to operate independently of the public grid. This means that if the wind hub needs to disconnect from the public electricity grid—for example, during its yearly maintenance—the battery can step in to keep the local energy system running independently to ensure continuity of renewable energy generation and powering of auxiliary systems of the wind turbines, thereby saving the operator time and money. 

“The Zeeland power distribution system requires battery systems to provide grid balancing services,” explains Rick Wasser, director of E-Connection. “As a large wind farm operator, we are happy that we have found a way to meet those needs at our site on Neeltje Jans. It adds robustness to the local grid, as well as to the grid of distribution system operator TenneT to which it is connected.” 

Alfen as full EPC partner

Alfen is delivering this project as a complete Engineering, Procurement, and Construction (EPC) provider, responsible for: 

• Civil works 
• Medium-voltage (MV) grid integration 
• End-2-end delivery, construction, engineering and commissioning of TheBattery system  

This turnkey approach ensures seamless integration with E-Connection’s wind assets, delivering an end-to-end solution.  

Set to be operational in the first quarter of 2026, the project highlights how battery storage can maximise wind energy efficiency while ensuring grid stability. 

About Alfen 

Alfen is at the forefront of Europe’s energy transition, providing integrated solutions that help customers address their electricity challenges and achieve climate neutrality. With a history of innovation dating back to 1937, Alfen’s energy storage systems, smart grid solutions, and EV charging stations are installed across more than 30 countries in Europe. The company has been developing energy storage systems since 2011, with installations totalling over 1+ GWh of energy capacity across 11 European countries.  

For more about Alfen’s TheBattery solutions, visit TheBattery.  

About E-Connection 

E-Connection develops, builds, operates and owns complex and innovative renewable energy projects as well as private HV-grid connections for more than 30 years, in close cooperation with the community and with an eye for nature. With several wind farms, E-Connection is contributing to the decarbonisation of the Dutch energy sector. And with this EOS Volans project, E-Connection is expanding its activities with energy storage. In short, E-Connection is committed to delivering reliable and sustainable energy solutions.