The goals for the future are even more ambitious. Switzerland wants to shut down its nuclear power stations by 2050 and switch completely to renewables. Therefore, small hydropower plants, such as “Kraftwerk Doppelpower”, “Kraftwerk Rufi” and “Kraftwerk Cotlan”, based in the Canton of Glarus, are playing an increasingly important role.“With these projects we have reached the limits of what is possible – and pushed beyond them,” says Wim Feyen, Senior Construction Manager at contractor K-Boringen from Belgium. K-Boringen carried out the pipe jacking work for the power plants. They produce electricity for 8,700 households.
Rockslides with giant boulders, gravel, high water pressure, extremely hard rock, large pipe diameters of up to 3.8 meters and gallery lengths of way more than 1,000 meters were real challenges for Feyen and his crew. Additionally, during the pipe jacking operations the machines had to pass beneath underground pipes, alpine rivers or a railway line with a small overburden. For the “KW Rufi” power plant, the machine drove a 3D curve with a radius of 260 meters – a record for a gallery like this. “Herrenknecht‘s machines mastered the complex tasks brilliantly,” says Feyen. “What I also like about working with them: when there are problems, you solve them together.”