Under the contract with E.ON Kraftwerke, Voith will replace, assemble and commission the stator and rotor of machine 6 at the plant.
The project is expected to increase the machine unit’s efficiency by around 10%.The contract includes a €5m option for further modernisation at the facility.
The Waldeck 2 pumped-storage power station features two generators, which have a 265 MVA capacity.
Voith supplied the original generators when the plant was constructed in 1970.
The company said the vertical placement of the classical pump-turbine unit presents a challenge in modernization. The turbine is located vertically above the motor-generator and a multi-stage pump is installed below. Voith is required to first disassemble the original turbine to replace the generator.
Voith Hydro chairman of the management board Roland Münch said: "Pumped storage power plants such as Waldeck will continue to make a vital contribution to secure and stable energy supplies.
"As giant batteries they store energy from irregularly available regenerative sources such as wind and solar and feed this energy quickly and flexibly back into the grid as and when required.
"Hydropower is reliable, sustainable and climate-friendly, and has long become an indispensable part of the renewable energy mix. This is why we are consistently developing our technologies for utilizing these energy sources."
