Pumped storage hydropower (PSH)

Pumped storage hydropower contributes to the balance of the electricity network while limiting production costs during peak consumption periods

Stockage hydraulique par pompage-turbinage

Pumped storage power stations operate using two water reservoirs at different elevations. They can operate the turbines to generate electricity during peak demand periods, while the water is pumped back up from the lower reservoir to the higher reservoir during off-peak times.


The turbine can be activated at any time to cope with peak consumption or inversely, pump water to absorb excess electricity production from the network. 


PSH is a flexible, simple and proven technology, which currently represents the only large-scale storage mechanism and is essential to the short-term equilibrium of electricity networks. 


Key figures in 2023

  • Pumped storage capacities (2023) 3.8 GW