To provide Network Rail a supply connection for their electrification scheme for the Trans Pennine Railway scheme. This involved the supply of two new traction transformers, fault limiting reactors and connecting to the existing 275kV GIS substation at Stalybridge.

Stalybridge 275kV GIS substation was extended at either end of the substation creating two new circuits. The GIS was extended outside the GIS building by GIB to AIS bushings to connect to the new 275kV HV AIS plant via step down transformers to 25kV cable sealing ends. The 25kV substation was built in a separate compound and connected to the main site via HV cables. The HV cables were installed in ducts beneath a live road by Horizontal Directional Drilling (HDD).

The existing 300kVA diesel generator was deemed to be insufficient to support the additional works and was replaced with a self-contained 500kVA unit. The extension also included new protections, extensions to the SCS and a Portable Relay Room.

The following summarises the civil works under this project:

  • Ground works for the 25kV and 275kV substation sites.
  • Design and construction of new piled Super Grid Transformer plinths and bunds.
  • Extension of substation road to accommodate SGT delivery and maintenance.
  • Design and construction of all civil works for the new Substation HV plant and structures and extension of existing cable trench system.
  • New 25kV Compound Substation boundary fence.