Preliminary study for Litti-Baar 132 kV AIS substation (BIM), Switzerland

New air insulated switchgear (AIS) 132 kV substation to supply the Zimmerberg Base Tunnel 2

AFRY has prepared a preliminary study using BIM to clarify the feasibility and space requirements of a new AIS design substation to supply the Zimmerberg Base Tunnel 2.

The route between Zurich and Zug, which is partially single-track, is a bottleneck in the Swiss railway network. Additional connections are no longer possible in spite of the continuing increase in demand. This bottleneck between Thalwil and Zug is planned to be eliminated with the Zimmerberg Base Tunnel II (ZBT II) as part of the STEP Expansion Step (AS) 2035 programme.

To service the Zimmerberg Base Tunnel II (ZBT II), the SBB requires a new substation in the vicinity of the tunnel portal in ‘Litti-Baar’.

In the preliminary study, several possible alternatives for the new substation were developed and evaluated. The main focus of the preliminary project was to determine the space requirements and to find an optimal layout at the given location. In the process, various technology options were analysed.

3D computer model of the Litti Baar substation on a black background
3D BIM model of the proposed Litti Baar substation

The BIM method

The layout planning of the new substation was completed using BIM. Primetech 3D was applied for the AIS switchgear. The BIM methodology was comprehensively used across all technical disciplines. The technology favoured by the customer can now be employed.