Irish transmission system operator (TSO) EirGrid has completed the first phase of marine and coastal surveys along Ireland’s south coast, which includes cable route corridor options from Maritime Area A, or Tonn Nua, offshore wind area of the Irish Government’s South Coast Designated Maritime Area Plan (SC-DMAP) .
The survey work is being carried out by Fugro as part of EirGrid’s Powering Up Offshore – South Coast project and under the TSO’s Offshore Marine Survey Framework, with subcontractors TechWorks Marine and Green Rebel conducting metocean and environmental surveys, respectively.
The work, which began in July 2025, covered geophysical, environmental and metocean surveys around potential subsea cable route corridor options in Maritime Area A, as well as intertidal non-intrusive landfall investigations.
Over the course of the 2025 campaign, the company surveyed 3,770 kilometres of seabed, involving more than 40,000 man-hours, with engagement from fisheries, industry and local communities, EirGrid said earlier this month.
Two metocean data buoys have been deployed and will remain on site until late 2026 to support offshore planning and environmental monitoring.
EirGrid said the data collected in 2025 will now be analysed, and further surveys, including geophysical, geotechnical and unexploded ordnance (UXO) investigations, are planned to take place in 2026.
“These surveys would not be possible without a huge amount of coordination and strategic planning of staff across EirGrid, our strategic partners, fishing communities and local landowners”, said Liam Ryan , Chief Transformation, Technology and Offshore Officer at EirGrid.
“The data being gathered from this research is essential in shaping plans for the installation of this transmission infrastructure for offshore wind and creating a cleaner energy future for Ireland by helping to inform our optioneering processes, technical and design elements and build on our understanding of the environment in the vicinity of our potential offshore cable routes and offshore substation locations.”
EirGrid said the project aims to deliver grid transmission infrastructure to connect up to 900 MW of offshore wind capacity to onshore points along the south coast, which is in line with Ireland’s climate action targets.