Before Cleuson-Dixence was built, approximately 2,200 hours were needed to empty the Grande Dixence dam, in other words, the turbines had to operate at full capacity 11 hours a day from October to April.
The new Cleuson-Dixence hydropower scheme enables production to be concentrated over just 1,000 hours, thus multiplying the Alpiq and Grande Dixence generating capacity by 2.5. It enables the output of a big nuclear power plant to be injected into the very high voltage grid in three minutes.
Built entirely underground between 1993 and 1998 by EOS and Grande Dixence at a cost of CHF 1.3 billion, the scheme comprises:
- a new water intake in the Grande Dixence dam
- 15.8 kilometres of collecting works
- a surge tank dug out of the Dent-de-Nendaz mountainside
- a 4.3 km steel-lined shaft
- the Bieudron underground powerhouse
Bieudron power plant - alt. 481 m
3 Pelton turbines – Total capacity: 1269 MW (1395 MVA)
Gross head: 1883 m
380 kV grid connection
The Cleuson-Dixence complex is closely linked to the operating of the Grande Dixence SA facility.
After the accident at the Bieudron power station in December 2000, it stood idle for nine years. Following completion of the repair work, the Cleuson-Dixence complex was put back into service in January 2010.
Grande Dixence dam - alt. 2365 m
Built: 1951 - 1961
Type: gravity dam
Height: 285 m
Crest: 700 m
Reservoir capacity: 400 mn. m3
Area: 4.04 km2
Catchment area: 46.3 km2
Experience the power of water
Discover the power plant in the hart of the Alps.
Storage Power Plants
Bieudron station, Riddes, VS
3 Pelton turbines
Cleuson-Dixence Société simple: Alpiq 7/22 and Grande Dixence SA: 15/22
2000 GWh together with Grande Dixence facility