H&MV Engineering were appointed to deliver a full turnkey 110kV Gas Insulated Substation (GIS) for a wind farm connection. The connection offer was with EirGrid and the hand over was to asset owner ESB.

The existing ‘tail fed’ Garvagh 110kV Substation (provided for the ESB Wind Garvagh Glebe/Tullynahaw WF connection) was being extended to accommodate the Derrysallagh WF connection and provision for future 110kV connections. For the Garvagh project, H&MV’s scope consisted of the civil, structural and building works at the 110 kV Substation associated with the contestable build. The scope included excavation and ground works, equipment foundations, plinths, cable trenches and ducts for 110 kV, 38 kV, LV and control cables within the Substation Extension GIS building.  The Substation extension cable basement was sized to accommodate the future extension to a full 8 bay enhanced ring busbar 110kV Substation. It featured access stairways to the basement at both ends of the building and a gantry crane, floor openings/pockets for future switchgear extension, roller shutter door, internal road and footpaths around the GIS building.

The scope extended to fencing, gates and stoning to complete the Substation extension compound and interface with the existing ESBN Garvagh Substation. We constructed new and modified access roads and reinstatement and landscaping as required to complete the extension and interface to the existing Substation and a storm water drainage system.

Our project team installed the earthing systems and connections to all equipment, steel support structures, fencing, gates and building structures, including provision for connections to the existing Garvagh Substation earthing grid. Our HV Engineers and Commissioners completed the installation testing and pre-commissioning of the completed works to ESBN requirements for handover to the ESBN Commissioning Engineer.

H&MV Engineering thrives on being flexible, dynamic and agile with proven technical knowledge, experienced  and competent staff, with the expertise to quickly mobilize to manage large HV Networks and Distribution projects. The delivery of this project in a safe, high quality, cost effective and timely fashion demonstrates these skills.