Tractebel supports major battery storage project in Germany

As Germany accelerates its energy transition, large-scale battery energy storage systems (BESS) are becoming critical to ensuring a reliable, flexible and resilient electricity grid. Tractebel is supporting the development of the Weissenthurm-Kettig BESS project, a major battery energy storage facility that will help stabilize the grid, optimize renewable energy integration and strengthen energy security.

Commissioned by VERBUND, Austria’s leading energy company and one of the largest producers of hydroelectricity in Europe, the project marks another important milestone in the expansion of Germany’s storage infrastructure and highlights the growing role of battery systems in enabling a low-carbon energy future.

Tractebel named project manager at Weissenthurm-Kettig

Tractebel’s renewable energy experts are responsible for project management covering planning and permitting, as well as construction supervision and coordination with the building authorities. The project, which began in December 2024,  is currently progressing according to schedule. Commissioning is slated for February 2027. This landmark development spans an area of approximately 8,000 m² and includes:

• 2,750 tons of precast reinforced concrete foundations
• 17 medium-voltage supply units
• Two technical buildings for high- and medium-voltage systems
• A 300-m cable route connecting the facility to Westnetz’s 110 kV grid
• A comprehensive safety system including perimeter fencing, video surveillance, lightning protection and access control

The 8,000 m² Weissenthurm-Kettig BESS project will provide an output of 50 MW over two hours

Delivering flexibility, resilience and grid stability

Located in western Germany along the Rhine River, the battery storage facility will provide an output of 50 MW over a duration of two hours, with an installed storage capacity of approximately 123,000 kWh. The system consists of 165 battery cubes, each with a nominal capacity of 745 kWh, enabling the facility to inject significant amounts of electricity into the grid when needed.

Major installation works completed, final integration underway

All outdoor technical equipment has been installed or mounted on its foundations, and the cable routes and cable ducts have been completed. The cooling systems for the 165 battery blocks are temporarily connected and operational to prevent any loss of battery capacity. Cabling work (connecting all individual components to the technical buildings) is underway, and the final section of the building (the medium-voltage area) will be constructed shortly.

Starting in late July, control and switchgear cabinets will be installed and wired within the building. The 300-meter-long cable route for connection to the Westnetz power grid is also currently being constructed. In parallel, final exterior work—such as path paving, site grading, fencing, the lightning protection system, and lighting poles—will be carried out in the coming months.

Powering Germany’s energy transition

The storage facility will provide critical services that support the stability and reliability of the electricity grid. It will stabilize the grid frequency by providing operating reserves, smooth out price spikes through the provision of flexibility in spot and intraday trading, and level the volatility that arises in electricity generation from renewable energies.

Weissenthurm-Kettig is one of many battery energy storage initiatives currently supported by Tractebel worldwide, helping clients in their transition towards more sustainable, resilient and independent energy systems.

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