Alpiq Group's Forces Motrices Hongrin-LĂ©man (FHML) has opened its 480MW Veytaux underground pumped storage power station in the Canton of Vaud, Switzerland.

The plant is touted to be the second most powerful pumped storage power station in Switzerland.

Located in the canton of Vaud at Veytaux, the pumped storage power station keeps 60MW of its total output as a reserve.

Its stakeholders include Romande Energie with 41.14%, Alpiq with 39.29%, Groupe E with 13.14% and the City of Lausanne with 6.43%.

According to FHML, the power station also has the capability to pump water to the Hongrin reservoir from Lake Geneva with a capacity of 420 MW.

The power station was originally designed to have 240MW of capacity. It has been expanded to 480MW with the addition of two pump turbine groups of 120MW each.

The new pump turbine groups are now fully operational six years after the power station broke ground.

Constructed in a cavern of 100x25x56m, the pump turbine groups are remotely controlled by Centre d’Exploitation et de Gestion de la Production in Lausanne owned by Alpiq.

FMHL board of directors chairman Pierre-Alain Urech said: "The new FMHL power station will make a significant contribution towards meeting our country’s future power supply challenges and is perfectly in line with the Energy Strategy 2050.”

The Veytaux pumped storage power station is likely to produce around 1 billion kWh of peak energy annually. This would be equivalent to meeting the energy needs of 300,000 Swiss households.

The power station is now claimed to generate twice the power output of 520 million kWh it had prior to the construction work.

Image: Two new groups of pump turbines with 120 MW each. Photo: courtesy of David Picard.