Fluence and LEAG Begin Construction on 100MW/400MWh Storage in Germany

en.Wedoany.com Reported - Fluence and German utility LEAG have begun construction on their second battery energy storage project in Germany, with the projects currently being deployed in partnership also including what will be Europe's largest battery energy storage system (BESS) to date.

Fluence announced on August 13 that construction has commenced on the Heinersbrück GridBattery project (100MW/400MWh) in the state of Brandenburg, Germany. Fluence is working with project owner LEAG Clean Energy, one of three new energy business subsidiaries under LEAG. Headquartered in the Lusatia region bordering Poland, LEAG is one of Germany's largest utility companies and is diversifying its existing assets in lignite mining and power generation through new technologies such as renewable energy and energy storage.

In line with common practice in Germany in recent years, the Heinersbrück GridBattery will be located on a reclaimed former open-cast mining site, co-located with renewable energy generation assets, and connected to the grid via LEAG's Heinersbrück substation. Germany plans to phase out coal by 2038, and LEAG is advancing a strategic renewable energy initiative called "GigawattFactory" to support this transition.

The GigawattFactory includes large-scale solar PV and wind power at the Bohrau Energy Park. Currently, the first 133MWp of PV is under construction, with the 105MW Forst-Briesnig II wind farm progressing in parallel, both connected to the 110kV distribution grid via the Heinersbrück substation. LEAG is also building large-scale battery energy storage and hydrogen electrolyzers to optimize the grid integration and operation of the GigawattFactory generation assets.

In November 2025, LEAG Clean Energy and Fluence announced their first collaborative project—GigaBattery Jänschwalde 1000. This standalone BESS has a capacity of 1GW/4GWh and is located on a former open-cast mining site in the town of Jänschwalde in the Lusatia region, near the Bohrau Energy Park and an existing 3GW lignite power plant. LEAG previously owned two open-cast lignite mines that were closed in 2023, one of which has been transformed into a lake and wildlife sanctuary near Cottbus-Nord. When the project was announced, Thomas Brandenburg, Managing Director of LEAG Clean Energy, stated that this 4-hour duration technology design "supports the further expansion of GigawattFactory renewable energy, helps stabilize the grid, and, with lower specific investment costs, optimizes the utilization of existing grid connections."

Currently, Europe's largest BESS project is the Coalburn 1 BESS (500MW/1,000MWh) in Scotland, UK, which was recently brought into commercial operation by its owner, Copenhagen Infrastructure Partners (CIP). Speaking again last week, Brandenburg said that Heinersbrück GridBattery is LEAG's first BESS to share a grid connection point with PV and wind assets. "This allows us to flexibly store surplus renewable electricity and feed it back when needed. In this way, we increase the efficiency of the energy system, relieve pressure on the grid, and strengthen supply security." Fluence is supplying its SmartStack 7.5MWh AC block BESS solution for both GigaBattery Jänschwalde 1000 and Heinersbrück GridBattery.

LEAG is also working with Chinese energy storage system integrator Hyperstrong to advance another major GigawattFactory BESS project. In a deal also announced in November 2025, Hyperstrong was appointed as the engineering, procurement, and construction (EPC) partner and BESS supplier for GigaBattery Boxberg 400. The project, located on the site of LEAG's former gas-fired power plant in Saxony, has a capacity of 400MW/1,600MWh.

Julian Jansen, Managing Director of Fluence Germany, said that as a company with deep German roots, Fluence shares LEAG's commitment to establishing large-scale energy storage as a key pillar of a modern and resilient German energy system. Jansen noted that Fluence has signed or deployed 35 projects in Germany with a cumulative capacity exceeding 6GWh. Fluence is a joint venture between U.S. power producer AES Corporation and Germany-based Siemens, and Germany is an important market among its approximately 17 regional markets.

Fluence released its latest financial results in early August. The company's revenue and profitability were impacted by delays in the capacity ramp-up at its U.S. contract manufacturing plant, leading to a lowered guidance; meanwhile, contract backlog grew to a record $6.5 billion, and the company secured its first data center orders. CEO Julian Nebreda stated that the ramp-up will enable Fluence to reach target levels by early 2027 to meet growing customer demand, and that the company is confident in its long-term opportunities and its positioning to capture them.