Cyclical Processes related to Underground Pumped Storage Power Plants using abandoned mines© Martin Brechtl
The storage of electrical energy is becoming increasingly important in the context of the energy transition. On an international level, the Institute for Mine Surveying, Mining Subsidence Engineering and Geophysics in Mining (IFM) is therefore conducting research in cooperation with other university institutes on the possibilities of underground pumped storage plants in old mines. The focus is on monitoring the plant with regard to long-term stability and mine gas development in the context of cyclical filling and pumping processes.
Coal phase-out and a move away from nuclear energy are certain in Germany. The share of energy from volatile sources will also grow globally in the future. Against this background, uncertainties arise with regard to the constant availability of electrical power. In this context, IFM is working on the feasibility of an underground pumped storage plant (UPSP). This should make it possible to store an energy surplus in the electrical grid and to retrieve it when needed. Since, for geographical reasons, Germany has hardly any capacity for the construction of further conventional pumped-storage plants, the idea of using disused coal mines for this purpose has come into focus. In this way, the remaining structures of the old mines could also be used sensibly and sustainably.
In cooperation with other institutes at RWTH Aachen University and the China University of Mining and Technology in Xuzhou, and with funding from the German Research Foundation (DFG), IFM is investigating in particular the effects of cyclical processes during the operation of a UPSP.