Gougra storage power plant

The Gougra power plant harnesses the power of the waters from Val d’Anniviers and the Turtmann Valley thanks primarily to the Moiry dam, which was constructed in 1954 above Grimentz. The dam is 148 meters high and 610 meters long. The water is fed from the reservoir to the power stations in Mottec, Vissoie and Chippis (Navizence).

Moiry dam – alt. 2249 m

  • Type: Arch-gravity dam

  • Concrete volume: 814,500 m3

  • Height: 148 m

  • Length: 610 m

  • Reservoir capacity: 77 million m3

Turtmann dam – alt. 2177 m

  • Type: Arched prestressed concrete dam

  • Height: 30 m

  • Length: 110 m

  • Reservoir capacity: 780,000 m3

Moiry-Mottec head – Collected in the Moiry reservoir

  • Headrace tunnel: Length 3,380 m, diameter 2.4 m, capacity 12 m3/s

  • Geology: Gneiss

  • Pressure shaft: Length 1,050 m, diameter 1.7/1.5 m, incline 80 %

  • Energy coefficient: 1.324 to 1.551 kWh/m3

Mottec-Vissoie head

  • Headrace tunnel: Length 6,910 m, diameter 2.4 m, capacity 12 m3/s

  • Geology: Gneiss

  • Pressure line: Length 900 m, diameter 1.7/1.5 m, incline 68 %

  • Energy coefficient: 0.986 kWh/m3

Vissoie-Chippis head

  • Pressure tunnel: Length 8,500 m, diameter 2.3x1.9 m, capacity 11.5 m3/s

  • Geology: Paragneiss

  • Pressure line: Length 1,106 m, diameter 1.67 m, incline 70 %

  • Energy coefficient: 1.277 kWh/m3

Facts & figures

Plant type:

Storage power plant

Location:

Anniviers/Tourtemagne, Switzerland

Number of turbines:

Mottec: 3 Pelton turbines and 2 pumps / Vissoie: 3 Pelton turbines / Navizence: 3 Pelton turbines

Capacity:

164 MW

Shareholding:

54 %

Commissioning:

1958

Average annual production:

643 GWh

Guided tours:

Yes

Status:

In service

Certificates