© SUREVIVE
Innovative battery storage connected to the grid
On 10 October, a battery storage farm operated by a consortium formed by Westnetz, Schoenergie GmbH, the Fraunhofer Institute for Solar Energy Systems ISE and Stuttgart University was connected to the grid. The field test is about integrating battery storage, several grid-forming power inverters with a capacity of more than a MW, existing PV installations and electricity consumers.
Grid-forming power inverters are key-enabling technologies for the future electricity system. So far, grid stability has mainly been assured by power plants with rotating generators. In future, this task will be taken on by inverters, which will, for instance, provide an inertial reserve (a reserve that is capable of rebalancing the grid within the space of milliseconds and therefore indispensable for stable operations). Without a sufficient inertial reserve, the grid would be more vulnerable to disruption and even blackouts.
20 megawatts of installed capacity and 54 megawatts of storage capacity
Combining battery storage and grid-forming power inverters makes it possible to boot the electricity grid again after a large blackout. As part of the SUREVIVE project (stability experiments with an inertial reserve from installations that are part of the distribution network), a storage farm has been directly connected up to a transformer station between the medium voltage and the high voltage grids to ensure that the medium voltage grid can be restarted after a blackout.
The battery storage farm has an installed capacity of 20 MW and a storage capacity of 54 MWh. From the start of operations, field experiments for real-life experience with grid-forming power inverters began with a view to supporting their integration into a market-based procurement of inertial reserve starting at the beginning of 2026.
Guidelines for the connection and operation of grid-forming power inverters in distribution networks
One intended outcome of the field experiments is to be the establishment of guidelines for the connection and operation of grid-forming power inverters in distribution networks. These guidelines are to be aimed at installation manufacturers, project managers and operators, and at distribution system operators.
The SUREVIVE project is embedded in the System Stability Roadmap and supported by an advisory board. The Federal Ministry for Economic Affairs and Energy is also represented on that advisory board. The project has been running since July 2024 and is to be completed in June 2028. It receives some €5 million in funding from the 8th Energy Research Programme of the Federal Ministry for Economic Affairs and Energy.