Voith Hydro has won an order from ENGIE Electrabel to upgrade three power units at Belgium’s largest pumped storage power plant, Coo-Trois-Ponts. The project will take four years and will bring a 79MW increase in plant capacity.

An international team of Voith Hydro engineers in Germany and the USA will undertake model testing, while the subsequent work on turbines and generators to increase performance will be conducted partly on site in the power plant and partly at Voith’s facilities in Heidenheim.

Among other things, new runners and distributors will be manufactured for the turbines. For the generators, the priority will be to improve cooling and insulation. For Voith Hydro, the project is an important follow-up order from ENGIE Electrabel; Voith had earlier completed an extensive automation contract that included the supply of new ‘control and excitation technology’ as well as speed governors for the power plant’s six machines.

Pumped storage is an essential part of Belgium’s energy mix and is currently the only option for storing electricity on a large scale, with the Coo power plant essential to maintaining balance in the grid. The turbines can currently be ramped up at any time to balance out a sudden drop in generation or absorb excess power.

If demand is too low, Coo ‘stores the electricity’ that has been produced at another location and makes it available again at peak consumption times. The maximum output of the power plant is 1,080MW, making it one of the most efficient plants of its kind in Europe.

Today, Voith has more than 20,000 employees, sales of 4.2 billion euros and locations in over 60 countries. It is one of Europe’s larger family-owned companies.