Dr. Hubert Lienhard, President and CEO of Voith AG spoke for all suppliers as he thanked Illwerke AG for the good and successful cooperation: "All of us are proud to have been able to contribute to this trendsetting project. We wish Kopswerk II and its operators a productive future and safe and accident-free operation."

Pumped storage power plants are the backbone of modern electricity supply. In the light of an increasing share of renewable energies from wind or solar worldwide, the importance of pumped storage for grid stability will grow further, too.

Kopswerk II sets standards with regard to available volume and response times. Within seconds, it can feed up to 525 MW into the grid to serve peak load demand, or absorb up to 450 MW of surplus energy form the grid to store during low demand phases. Each of the plant's units consists of a Pelton turbine, a motor-generator, a starting converter, and a storage pump. For good reasons, Kopswerk II uses separate machine sets with separate pumps and turbines rather than reversible pump-turbines: The machine sets are designed to operate with so-called short hydraulic circuits, where the storage pump and the turbine can operate simultaneously. A certain amount of water is channeled to the turbine and generates electricity. As a result, the machine set is able to absorb just the amount of electricity available from the grid.

The stability of modern electrical grids with a rapidly growing share of wind energy relies on pumped storage plants such as Kopswerk II to a significant extent. Wind is intermittent, and during times of strong breezes pumped storage plants serve as storage medium, i.e. the surplus energy is absorbed from the grid to pump water into reservoirs. In times of low or no wind, the water from the reservoirs is used to generate energy on demand from the grid.

Currently, Voith Hydro also works on equipment for pumped storage schemes in Germany, Spain, North America and South Africa.

Voith Hydro is a Group Division of Voith and - with a workforce of around 3,600 employees and an order intake of almost 1.4 billion Euros in the past business year - belongs to the world-wide leading companies for hydro power equipment.

Voith is a global leader in the paper, energy, mobility and service industries. Founded on 1st January 1867, Voith employs 43,000, and has sales of EURO 4.9 billion. Operating from 290 locations worldwide, Voith is one of Europe's largest family-owned companies.