FMHL+ extension project of the existing Veytaux powerplant - ongoing works and interaction challenges
FMHL (Forces Motrices Hongrin-Leman SA) is the Owner of Veytaux power plant and belongs to the shareholders Romande Energie SA, Alpiq Suisse SA, Groupe E SA and the City of Lausanne. Alpiq Suisse SA (Alpiq), which acts as the Owner's representative, is in charge of the supervision of the study and the implementation of the extension project. The existing power plant is operated by HYDRO Exploitation SA. FMHL chose the GIHLEM consortium, constituted by Stucky, EDF-CIH and Emch-Berger, to design the project, prepare the tender documents including the specifications and bidding procedure and moreover the execution design and the supervising of the final commissioning of the new power plant.The FMHL+ project consists of extending the existing pumped-storage plant Veytaux I, built in the early seventies, by constructing a new power house cavern. The new power plant is integrated into the existing waterway between the lake Hongrin (upper reservoir with a capacity of around 52 Mio. m3 at 1255 masl), and the lower Leman Lake at 372masl, basically by connecting the new units to the existing pressure shaft and tailrace channel.To increase the total installed capacity of the plant from 240 MW (four ternary units with 60 MW each) to 480 MW (including 60 MW as reserve) using most of the existing upstream and downstream waterway and a gross head of 878 mWC is a challenging task. The new power plant comprises two new ternary units with a capacity of 120 MW each.