Most of the around 27-kilometre high-voltage line between Innertkirchen and Ulrichen, which passes over the Grimsel Pass, is over 60 years old and must be brought in line with the current state of the art. At the same time, the voltage will be increased from today's 220 kilovolts (kV) to 380 kV throughout. The increase in power of the line between Mettlen (LU) and Ulrichen is an important project in Swissgrid's «Strategic Grid 2025».
Why the project is necessary
The expansion of electricity production from hydropower is a central pillar of the Energy Strategy 2050; the replacement and power increase of the line between Innertkirchen and Ulrichen is important for transportation of the growing electricity production from the cantons of Berne, Valais and Ticino to the conurbations in the Swiss Central Plateau. The distribution of energy flows along several north-south axes also increases grid stability. In view of the federal government's energy strategy, the capacity increase is necessary to transport the growing electricity production from hydropower in the cantons of Bern, Valais and Ticino to the Swiss Central Plateau and to increase security of supply throughout Switzerland in the long term.
Sectoral planning process for transmission lines (SÜL) started
At the beginning of July 2020, Swissgrid submitted an application to the Swiss Federal Office of Energy (SFOE) for the definition of a planning corridor between Innertkirchen and Ulrichen in the Federal Transmission Lines Sectoral Plan. The first step was for Swissgrid to develop various corridor variants; these are geographical areas in which a route with a specific transmission technology—overhead line or underground cable—can be implemented once the project moves forward. Swissgrid has developed three main corridors, some of which include sub-variants: