Design and construction of the tunnel geothermal system in Jenbach / Planung und Bau der Tunnel-Geothermieanlage in Jenbach

On contract H8 - Tunnel Jenbach on the northern approach route to the Brenner Base Tunnel, a 54 km section of tunnel is currently being equipped with a geothermal system making use of energy lining segments, which enable the laying of absorber pipework in the TBM-driven tunnel. The system will be able to supply energy to the building yard in Jenbach though a connection in the emergency exit shaft. The design of the geothermal energy system covers the design of the energy segments, the sizing of the geothermal system, the installation of the segments in the tunnel and connecting them together in the tunnel and the laying of the connection pipework. Various restrictions resulting from the practicalities of tunnel construction had to be taken into account in the geothermal system. This article describes the experience gained during the design phase and the current state of the works. Then follows a discussion of the conditions for the future application of geothermal systems in tunnels.