Environmental Impact of Underground Pumped Storage

OECOS GmbH worked on the partial study “Pumped storage underground: Identification of critical points from the environmental perspective in the re-use of abandoned mines as pumped storage” as part of a research project on “Wind energy storage through re-use of disused mines” (FKZ: 0325074). The study was written for the Energy Research Centre of Lower Saxony (EFZN) as a subcontractor of the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU).

The aim of this research project is to investigate the potential of abandoned mines and for subsequent use as underground pumped storage power plants (PSWuT) to compensate for the discrepancies between wind power feed and loss. In this study possible area- and environmental-factor-related restrictions on the construction, installation and operation of underground pumped storage power plant were examined and evaluated both in general and on the basis of two model projects. It was found that, among other things, special attention should be paid to the possible remobilisation of pollutants deposited in deep water and the resulting potential construction and operational impacts on the water balance.