The Celtic Interconnector High Voltage Direct Current Electricity Cable (HVDC) will enable the exchange of 700 MW of electricity between Ireland and France. Moving this electricity across a distance of 575 kilometers, with 500 kilometers of the cable running under the sea, this interconnector will have the capacity to supply electricity to 450,000 homes. It will make an important contribution to shoring up Ireland's security of electricity supply by providing a direct link to continental Europe. Once complete, the Celtic Interconnector will run from Knockraha, in east Cork, under the sea and on to the French network connection point in La Martyre, Finistère, France. The project is a joint venture between the Irish transmission system operator (TSO) EirGrid and French TSO Réseau de Transport d'Électricité (RTE).

A HK250 Trailer HDD-Rig was used for the construction of the 3 parallel 440-meter-long HDD landfalls on the French Brittany coast. The DA 350 mm and DA 250 mm protection pipes run at a depth of 10-12 meter under the sea, beyond a field of laminaria algae to be preserved. The three horizontal directional drillings were successfully completed in July 2024.