A new type of substation is being built at the ÜSTRA Hannoversche Verkehrsbetriebe AG at the Hannover-Döhren site as part of the GUW+ research project funded by the BMVI. This will allow the existing electric light rail infrastructure to be used for charging battery buses. In order to absorb additional load peaks, provide grid-serving services and maintain limited operation in the event of a blackout, an energy storage unit will be integrated into the substation. After prior processing, this storage will be built from discarded bus batteries that no longer have the necessary capacity for mobile use in bus operation, but have not reached the end of their service life either. The stationary operation of the storage unit is part of a sustainable battery after-use concept.

The Chair of Electric Railways at the "Friedrich List" Faculty of Transport and Traffic Sciences accompanies the research project on a scientific level. Among other things, the professorship is conducting studies to clarify the connection conditions of the substation, to define and technically implement blackout scenarios, and to plan and evaluate the validation phase of the GUW+. The validation phase includes the preparation, implementation and evaluation of measurement campaigns in order to examine the operating modes of the GUW+ in real operation for the fulfilment of the technical, operational and economic objectives. The reproducibility of the findings obtained from the validation phase depends primarily on the preparation of the energy storage system in the GUW+ research project.

Therefore, the project partners are pleased that the bus manufacturer EvoBus, a subsidiary of Daimler AG, could be won as an associated partner for the research project. Together with Mercedes Benz Energy GmbH, an energy storage system is being prepared for the pilot application, with the help of which a future operation of the GUW+ can be mapped realistically.