The West of Ireland and County Mayo in particular has significant potential for the development of
renewable generation, particularly wind and ocean energy (tidal/wave). EirGrid is planning to provide
infrastructure to connect 647MW of wind energy from a number of wind farm developments in County
Mayo, in the Bellacorick area. To accommodate these connections and as part of the EirGrid Grid25
strategy to develop the Irish electricity transmission system, EirGrid is planning a new electricity
transmission line from the Bellacorick area (hereafter referred to as the Bellacorick node) to connect to
the existing grid at either of the existing 220 kV substations at Flagford in County Roscommon or Cashla
in County Galway. EirGrid�s analysis of the requirements of this line has concluded that a new 400 kV
line with associated substation at the Bellacorick node and extensions to the existing substation at either
Flagford or Cashla will be required. This project is designated the Grid West project.