BW ESS Begins Construction on 1GW/5.7GWh Energy Storage Project in Germany
en.Wedoany.com Reported - BW ESS's first energy storage project in Germany—the Klostermansfeld Centralized Energy Storage Station—has commenced full construction. With a capacity of 1GW/5.7GWh, it is currently the largest energy storage project under construction in Germany. The company completed a 100% equity acquisition of the project in early 2026, achieving full ownership and development control.
The project is located in the Mansfeld-Südharz district of Saxony-Anhalt, Germany, as a single large-scale centralized energy storage station. According to a BW ESS spokesperson speaking to ESS News, overall construction progress is steady, and the project is expected to commence commercial grid-connected operations in 2028.
The project was initially developed by Zelos Energy Developments, with BW ESS entering the investment landscape as early as 2024. After two years of deep engagement and advancement, BW ESS completed the full acquisition in early 2026. Zelos Energy Developments continues to support project implementation, handling local site-related matters. Technical and site support will extend until the second half of 2026, after which the team will formally conclude its involvement once the project enters a stable construction phase.
A key highlight of this construction start is that the project is entirely funded by BW ESS's own capital, with no external financing involved, ensuring strong financial autonomy. Regarding the project's future revenue and operational model, the company is still refining its approach. With its massive 1GW/5.7GWh capacity, the project can provide over four hours of long-duration energy storage regulation, setting a new record for single energy storage projects in Germany and establishing itself as a benchmark in the local long-duration storage sector.
Roberto Jiménez, Managing Director of BW ESS, stated that the German energy storage market holds long-term development potential, and the company remains committed to deepening its presence in the local new energy sector. As BW ESS's first energy storage asset to break ground in Germany, this project will serve as a key regional foothold. The company will leverage its global experience in project construction and operations to facilitate the cross-regional application of technical and operational expertise, continuously strengthening its European energy storage market presence.
BW ESS is a subsidiary of the multinational maritime group BW Group, whose business spans shipping, offshore gas facilities, and deep-sea oil and gas development. Leveraging the resources of its parent company, BW ESS has been actively expanding in the global energy storage sector in recent years, steadily growing its business footprint to cover countries including the UK, Australia, Italy, Germany, Spain, and Sweden.
As of now, BW ESS has over 540MWh of energy storage projects connected to the grid globally, with approximately 11GWh of total capacity under construction. In addition to the massive German energy storage project now under construction, the company has previously entered into a strategic partnership with Munich-based energy storage developer MIRAI Power to jointly develop a 1GW energy storage project in southern Germany. Meanwhile, BW ESS has also participated in the first publicly implemented capacity lease agreement in the UK energy storage market. With these multiple strategic initiatives, the pace of its overseas energy storage expansion continues to accelerate.
