On 29th May 1951, the Société Electrique de l'Our S.A. (SEO), was formed upon the initiative of the government of Luxembourg.
In addition to the exploitation of the pumed storage plant in Vianden, the group SEO exploits different run of river plants an wind farms.
The surplus energy thus available during off-peak hours is used to pump water from a lower reservoir to an elevated storage basin. This water is released during peak hours to produce high-value current. The Vianden powerstation is connected to the german power grid and represents an important link in the western European interconnected network. The first scheme of nine 100.000 kW sets comprises three main works:
- the upper reservoir consisting of two artificial basins
- the lower reservoir was created in the Our valley by the erection of a gravity dam up-stream from Vianden al the place called “Lohmühle";
- the underground power house