The Waldeck Pumped Storage Scheme consists of two power plants, Waldeck 1 and Waldeck 2. Each station draws water from a separate upper reservoir and empties into Affolderner lake. Both plants were built to shift energy from off-peak demand hours to peak demand hours.

Waldeck 2 contains two machine sets with Francis turbines rated at 140 MW each. E·ON has been planning to add 300 MW of capacity to Waldeck 2 since 2010, but construction has yet to begin.

Open-loop Pumped Hydro Storage