Influence of pumped-storage operation on reservoir sedimentation

In Europe, renewable energy sources are rapidly growing but are often linked to a highly volatile production, as for solar and wind energy. Pumped-storage plants have become very important since they can ensure grid stability and safe power supply at any moment. In Alpine countries, many new pumped-storage schemes are planned or already under construction, often using the artificial lakes of existing storage power plants as upper or lower reservoir. The sustainable use of these reservoirs is endangered by sedimentation. In the Framework of a research project it was studied for the first time if sedimentation behavior can be correlated to pumped-storage sequences. The relevant problem was addressed applying an integrated approach combining prototype measurements with systematic laboratory experiments and numerical simulations. Results are helpful in designing location and type of inlets and outlets aiming to maintain high turbulence in the reservoir to reduce settling of suspended sediments.