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 S.A 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: 1950 - 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
3 Pelton turbines
Cleuson-Dixence Société simple: 15/22 Grande Dixence SA: 7/22 Alpiq Suisse SA
2,200 GWh together with Grande Dixence SA