These new installations contribute to the supply security of the French-speaking part of Switzerland and improve the stability of the transmission network.
After more than six years of construction, the new 380/220 kV transformer and the 380 kV gas-insulated substation (GIS) were brought into service on 6 October 2017. They are housed in a new building on the site of the former 220 kV overhead station, which dates back to the 1960s and was replaced in 2015 by a new 220 kV GIS.
It became necessary to modernise these facilities as electricity requirements have evolved significantly since that time. The new 380/220 kV transformer with an output of 800 MVA is also an integral part of Swissgrid's «Strategic Grid 2025» which is necessary to implement Switzerland's Energy Strategy 2050. In addition, the Bois-Tollot – Chamoson 380 kV electricity transmission line, which previously ran above the station, has been connected to these new installations, ensuring improved stability of the electricity transmission system.
However, work at the Romanel substation is still not complete: Lausanne Industrial Services (SiL) are currently completing construction of a new building which will house a 125 kV GIS, two 220/125 kV transformers, two 125 kV/MT transformers and a medium voltage substation.
The Romanel station is of considerable importance to the French-speaking part of Switzerland. The purpose of these new installations is to guarantee and improve electricity supply security for the Lake Geneva region.