Small Flex : Modèle d’exploitation flexible d’aménagements hydroélectriques de haute chute au fil de l’eau en Valais

The Kraftwerk Rhone Oberwald hydropower was selected as a pilot site to analyze the possibility of running hydropower plants along a river in alpine regions during winter months. The KRO Gletsch-Oberwald hydropower facility has been operating since the beginning of 2018 is a run-of-the-river installation that has been designed without restraint and only works when the Rhone's water supply is abundant, between the May and September. The flow of the Rhone outside this range cannot be turbined and are therefore lost. The project studies the possibility of storing those debris and turbining them in order to provide peak energy despite the lack of upstream basin. These waters will be stored in the settling basin, which is used as a settling basin when flows are plentiful and will pass through holes installed between the Settling basin and the forebay. Secondly, the project studies the sediment dynamics upstream of the intake in order to establish a threshold for the use of the Settling basin as a storage unit and to define the periods during which the settling basin will be used as a sand drap. The project also lists the improvements that should be made at the instrumentation level to reduce uncertainties about the estimates made. This project is part of the activities carried out at the Laboratory of Hydraulic Constructions at the Swiss Federal Institute of Technology in Lausanne as part of the energy transition in Switzerland (Swiss Competence Center for Energy Research - Supply of Electricity) including, in parallel, environmental monitoring activities and studies on the hydraulic machines of the plant.