German transmission system operator (TSO) TransnetBW GmbH is starting the construction of a 250-MW battery-based energy storage-as-transmission project in Baden-Wuerttemberg after the approval process was concluded.

Having received planning approval from the regional council of Stuttgart, the company intends to hold the groundbreaking ceremony on June 10 as planned. The system, also called a grid booster, will be installed at Kupferzell, a major North-South grid hub.

The facility will serve as a safety buffer in case of emergencies. It will enable the operation of the existing grid at a higher capacity than before, maintaining supply reliability without active energy feed-in. Thus, the need for additional power lines and interventions in grid operation will be reduced.

TransnetBW is working on the project in co-operation with energy storage solutions provider Fluence Energy which will supply the required components later in 2024.