Energie Electrique du Simplon is investing CHF 20 million in the comprehensive refurbishment of the Tannuwald hydropower plant in the Swiss canton of Valais, with the first of the new machine groups currently being installed.
The Tannuwald hydropower plant is a part of the hydropower complex Simplon belonging to Energie Electrique du Simplon. It is located in the Zwischbergental valley and utilises the waters from the Fah reservoir situated at an altitude of 1759m. The complex also includes the Gondo and Gabi power plants and the Eggen and Sera reservoirs.
The seven machine groups at the plant, which were commissioned in 1981, are being replaced by two new, more powerful groups. The first group consists of a Pelton turbine, generator and ball valve. The transformers and power lines are also being replaced.
The 2.8km pressure line connecting the Fah equalising reservoir with the power plant was already completely overhauled in the summer of 2019. This increased the capacity from 2.1m3 to 2.7m3 per second. The only part of the power plant that will be retained is the shell of the building, the height of which will, however, be increased by 2.6m.
The power plant is scheduled to resume operation in June 2020. The new systems will increase the power plant’s output from 5.8 to 6.8MW. In future, the plant will generate approximately 22GWh of electricity per year.
The shareholders of Energie Electrique du Simplon – Alpiq (81.9%), EnAlpin (10.8%), EWBN (3%), FMV (2.7%) and private shareholders (1.6%) – are continuously investing in the various plants in order to ensure efficient and productive operations over the long term. In 2017, EES modernised the Gondo hydropower plant. Starting in 2021, it will also upgrade the Gabi power plant to increase its capacity. The modernisation measures at the EES power plants are geared towards optimising the utilisation of the potential of hydropower and are in line with the Swiss federal Energy Strategy 2050.
After the recommissioning of the refurbished Tannuwald power plant, EES will operate with a total capacity of 75.8 MW and generate 243 million kWh of electricity per year on average, which corresponds to the annual electricity consumption of some 60,000 households.