Operator Alpiq’s Gondo plant in the Alpine municipality of Simplon came online in 1952 with a capacity of 45 MW. After its recommissioning in June, it is now rated at 57 MW and its average annual production has increased by 15 GW, now totalling 198 GW.
The modernization has also increased the flexibility of the power plant, which can now supply primary control power and reactive power to the nation’s grid operator Swissgrid.
The plant features three Pelton turbines. According to a press statement, the third turbine was replaced with a new turbine in order to increase output and generation capacity, while turbines 1 and 2 were overhauled in order to guarantee a high level of availability.
A range of measures was carried out on the machinery and the secondary components (control unit, regulation, protection, internal service and auxiliary installations). To optimize the operation, the plant is now controlled remotely from Alpiq’s operations centre in Lausanne.
Total investment in the modernization project amounted to CHF22m ($23m).
The Gondo plant uses water from Lake Sera in the Zwischbergental valley. It is a part of the Energie Electrique du Simplon hydropower facility, which also comprises the Gabi and Tannuwald plants and the Eggen and Fah reservoirs.
The total output of the complex is 74 MW and it generates an average of 247 GWh per year.