EirGrid, the Irish power transmission system operator (TSO), has unveiled its EUR6bn investment programme for the next five years (EirGrid press release, 23/06/2026). It aims to upgrade up to 1,000 km of existing circuits, add up to 450 km of new transmission lines, and 65 substations and to enable 3.5 GW of renewables, including offshore infrastructure and interconnectors for offshore wind. It also aims to maintain strong momentum on the North South Interconnector project, expected to be commissioned in 2031.
The plan also supports key offshore projects, including facilitating final investment decisions (FIDs) for Phase 1 East Coast developments and preparing planning applications for the Phase 2 South Coast Tonn Nua project by 2029. EirGrid also to complete all onshore works and energise the converter stations for the Celtic Interconnector in 2026, targeting a complete the installation of the marine cable for the Celtic Interconnector in 2028.
EirGrid aims to enable the power system to operate with up to 95% renewable sources by 2030 and 100% by 2035, integrating 500 MW of long duration storage. The programme is aligned with Ireland’s goal of generating 80% of its electricity from renewable sources, requiring the integration of 9 GW of onshore wind and 5 GW of offshore wind.