Large-scale storage system begins operation
In the Smart Power Flow project, scientists are testing the use of a large vanadium redox flow battery in a local low-voltage grid. The local storage system recently commenced operation in Tussenhausen in Bavaria.
The transformation of the energy provision in Germany is having a major impact on regional electricity grids. The grids were originally created for distributing the electrical current. Today, in Bavarian Swabia they are collecting increasingly more electricity from the numerous photovoltaic systems.
In the local low-voltage grid belonging to LEW Verteilnetz, researchers working in the Smart Power Flow project are investigating how a vanadium redox flow battery can be used as a large-scale storage system to relieve the electricity grid. The battery storage system is intended to support and relieve the regional electricity grid. It is to date the largest storage system of its kind in Bavaria. In addition to LVN, the Reiner Lemoine Institute, SMA Solar Technology and the storage pioneer Younicos are also involved in the pilot project.
It is intended that the new local storage system will temporarily store surplus electricity on the spot that has been produced from renewable energy and later deliver it on demand back into the local grid. The battery storage system therefore aims to create an efficient, local balance between the generation and consumption. The scientists are also investigating how regional grid expansion can be avoided through the use of battery storage systems. The local storage system helps to support the local voltage control, thus minimising future grid expansion costs and maximising the ability of the distribution grid to absorb renewable energy. In addition, the project partners want to try out various operational and marketing practices with the local storage system, such as voltage control, frequency control, reactive power management and participation in the balancing energy market.
Advantages of vanadium redox flow
The market town of Tussenhausen in the rural district of Unterallgäu was selected from 80 possible sites as the location for the local storage system. It was chosen because on the one hand several photovoltaic systems feed electricity into the local grid with a maximum output of 560 kilowatts and, on the other hand, a correspondingly large local grid transformer is present. The local storage system is the largest of its kind with an output of 200 kilowatts and a capacity of 400 kilowatt-hours, whereby the battery stores the electrical energy in the form of liquid electrolytes.
Vanadium redox flow batteries offer numerous advantages: they have a long service life, almost unlimited charging cycles and can be fully discharged without any problems. Thanks to the modular design, the battery capacity can be expanded as required and also requires hardly any maintenance. Large-scale storage systems are especially suitable for use as district storage systems or for industrial or commercial applications. For example, in future local communities, large-scale enterprises, commercial customers or agricultural businesses could use such storage systems to increase their own consumption or to participate in the balancing energy market.