Switzerland – Works for complete or part construction and civil engineering work – UW Winkeln - GU Baumeisterarbeiten und Gebäudetechnik

**General Project Information**

The secondary systems and auxiliary systems of the Winkeln substation have reached the end of their technical lifespan and need to be renewed. The combination transformers (except for SBB fields) will be replaced with modern transformers made of composite materials. The Swissgrid systems will be largely decoupled from the Axpo systems. For this purpose, Swissgrid is building a new, separate substation building. The project essentially comprises:

· Construction of Swissgrid substation building

· Renovation of existing field houses

· Creation of a separate building for grounding material

· Creation of a platform in the upper/lower plant level area for the busbar grounding

· Replacement of combination transformers

· Renewal of grounding system and lightning protection

· Renewal and decoupling of secondary systems

· Renewal and decoupling of telecommunications

· Replacement of auxiliary systems and accommodation in the new substation building

· Supply of own consumption by Axpo and SBB

· Renewal of Physical Protection of Substations (PSU) with fencing, gates, and monitoring

· Renewal of lighting for 220-kV outdoor switchgear

**Project Digital Construction**

The project "UW Winkeln 220 kV" is being implemented as a pilot project for Digital Construction. The aim is to apply the corresponding methodologies consistently for the construction and renovation of the substation to significantly improve planning, execution, and documentation quality. The contractor for packages 10+15 acts as the lead company on the construction site. The goals and requirements for package 10+15 include the mandatory use of the central CDE platform, model-based execution and as-built documentation, and the comprehensive provision of the digital construction site infrastructure, including a "Digital Control Room" and high-performance construction site internet.

**Digital Construction Requirements for the Main Contractor (Package 10+15)**

· **Leadership & Data Management:** The Main Contractor acts as the lead company. The entire project handling (documents, pending items, defects) is mandatory via the Swissgrid provided platform Autodesk Forma as the "Single Source of Truth".

· **Digital Construction Site Infrastructure:** The Main Contractor is responsible for providing and operating a "Digital Control Room" (BIM-Box) and a high-performance internet connection. In case of insufficient coverage, alternative systems including backup solutions (4G/5G) must be used.

· **Model-based Execution & Documentation:** The execution is based on 3D discipline models (BIM2Field), including digital staking and machine control. Geometric deviations must be continuously reported via CDE for as-built documentation (Field2BIM). The BIM methodology as part of Digital Construction is to be understood as an integral service and must be fully included in the unit prices; no separate remuneration will be made. The additional infrastructure (control room, network) will be remunerated additionally.

**Tender for Building and Building Services**

As part of the renovation project, a General Contractor (GU) tender is planned for the building and building services with the following structure, content, cost scope, and deadlines:

**10.01 Building Work Execution:**

· Construction site installation

· Temporary fencing (site and within the outdoor switchgear)

· Dismantling and disposal of existing apparatus foundations, cable duct blocks, sewerage systems, existing fence foundations, grounding systems, existing fencing, and secondary cables in the outdoor switchgear

· Foundations for apparatus racks, cable duct blocks, drainage, fencing, camera masts, gates, and interface cabinets

· Shell construction of new substation building (reinforced concrete construction)

· Asbestos removal of cable trays in the cable tunnel

· Site works

**Coordination:**

· All disciplines within the GU

· Interfaces to the outside

**15.01 Lightning Protection, Grounding, and Signage**

Design, execution, commissioning, training, and documentation:

· Lightning protection

· Grounding

· Room signage

**15.02 Electrical Installations incl. HVAC Cabling**

Design, execution, commissioning, training, and documentation:

· Electrical installations with all necessary measures for energy distribution and supply of building services: - Sub-distribution building services - Surface-mounted installations in all areas - Switches, pushbuttons, and sockets in interior spaces accessible via grid channels - Socket outlets in the outdoor area - Charging stations for electric vehicles in front of the building - Network connection sockets for WLAN access points and DECT antennas - Parapet channels in the control room - Cable ducts and riser zones for structured cable routing - Cable ladders in the raised floor for flexible cable laying - Power supply for HVAC systems (monoblock, outdoor unit, cooling units, KWL units, fire dampers, humidity/temperature sensors) with electrical energy - Interior lighting: Basic lighting with suspended light rail system throughout the building - Emergency lighting: Includes safety and standby lighting, emergency exit signs, portable safety lights, and a central emergency power supply - Lighting control: Control for basic lighting in the building with central on/off and area lighting with on/off function in the new substation building, the field houses, and the building for the grounding material.

**15.03 Central Control HVAC incl. Control Cabinet**

Design, execution, commissioning, training, and documentation:

· Central control HVAC incl. control cabinet and field devices

**15.04 Heating/Cooling**

Design, execution, commissioning, training, and documentation:

· Cooling and heating of substation building

· Electrical resistance heating of field houses

**15.05 Ventilation**

Design, execution, commissioning, training, and documentation:

· Ventilation system substation building general

· Ventilation system battery rooms