Author(s): Rodolfo Alvarado Montero; Andre Niemann; Dirk Schwanenberg
Linked Author(s): Dirk Schwanenberg
Keywords: Pumped storage; Hydropower; Energy storage; Coal mining; Renewable energy
Abstract: The further development of renewable energies and their integration into the German power grid is currently a primary task of the country’s energy policy. However, the problem of energy storage has not been fully solved yet. In addition to new energy storage technologies and conventional pump storage facilities, the implementation of underground pump storage is alternative for energy storage to be explored. Coal mining facilities in Germany are fading out due to environmental constraints as well as economic pressures related to the complexity of extracting material at greater depths. All of these facilities will end operations in 2018 and cavities inside the pits might become available for alternative uses. One of such potential uses is the implementation of an underground pumped storage project using the existing infrastructure as a lower reservoir. There is a high energy potential of these sites since the available head can reach up to 1200m inside the shafts. This head is sufficient to operate the pump storage plant even with small or medium underground storage reservoirs. Facilities of this type have not been yet developed, therefore, a validation of feasibility and an economic viability still needs to be done. This paper presents the current research on the feasibility of such projects using the example of the Prosper-Haniel mine in the Ruhr region in Germany. The options to establish a pumped-storage project could be either as a closed system (in which water is kept in a closed loop) or else in an open, interconnected system that uses the existing drainage network of various mines in the region. Both options are further explained in this document. Preliminary results display a range of possible configurations for underground pump storage facilities. Depending on the design flow and the configuration of equipment, the installed capacity may vary from 20MW to 400MW.
Year: 2013