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

**General Project Information**

The secondary equipment and ancillary 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. To this end, Swissgrid is constructing a new, dedicated substation building. The project essentially comprises:

· Construction of the Swissgrid substation building

· Renovation of the existing field houses

· Construction of a separate building for grounding material

· Construction of a platform in the upper/lower plant level area for 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 ancillary systems and accommodation in the new substation building

· Supply of self-consumption through Axpo and SBB

· Renewal of physical protection of substations (PSU) with fencing, gates, and monitoring

· Renewal of 220-kV outdoor switchgear lighting

**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 Planning House" and high-performance construction site internet.

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

· Lead & Data Management: The main contractor acts as the lead company. The entire project processing (documents, pending items, defects) is carried out mandatorily via the Swissgrid-provided Autodesk Forma platform as the "Single Source of Truth".

· Digital Construction Site Infrastructure: The main contractor is responsible for providing and operating a "Digital Planning House" (BIM-Box) and a high-performance internet connection. In case of insufficient access, 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 within the framework of digital construction is to be understood as an integrative service and must be fully included in the unit prices; no separate remuneration will be made. The additional infrastructure (planning house, network) will be additionally remunerated.

**Tender for Construction Work and Building Services**

As part of the renewal project, a general contractor (GU) tender is planned for the construction work and building services with the following structure, content, cost scope, and deadlines:

10.01 Construction Work Execution:

· Construction site installation

· Temporary fencing (site and within the outdoor switchgear)

· Dismantling and disposal of existing apparatus foundations, cable duct blocks, drainage 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 the new substation building (reinforced concrete construction)

· Asbestos removal of cable trays in the cable tunnel

· Surrounding works

Coordination:

· of all specialist areas within the GU

· of interfaces to the outside

15.01 Lightning Protection, Earthing, and Signage Design, execution, commissioning, training, and documentation:

· Lightning protection

· Earthing

· 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 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 trays and riser zones for structured cable management - Cable ladders in the raised floor for flexible cable laying - Supply of HVAC systems (monoblock, outdoor unit, cooling units, ventilation 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 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 generation substation building

· Electrical resistance heating field houses

15.05 Ventilation Design, execution, commissioning, training, and documentation:

· Ventilation system substation building General

· Ventilation system battery rooms