Celtic Interconnector - Feasibility Study

Why is this project needed?

We are currently undertaking a joint feasibility study to investigate the development of a High Voltage Direct Current (HVDC) interconnector between south Ireland and north-west France, called the “Celtic Interconnector”. This study is in collaboration with French transmission system operator, Réseau de transport d’électricité (RTE).

We have conducted initial joint studies which showed that an interconnector between the two countries could be beneficial for electricity customers in Ireland, France and the EU.

Based on these positive results a feasibility study of the project is being carried out. No decision has yet been made on whether or not to proceed with the proposed project. This decision will not be made until 2016 at the earliest and would be made with our partners on this proposal, RTE.

The route being considered for the Celtic Interconnector runs between the south coast of Ireland and the north west coast of France. The route is approximately 600 km long, of which the subsea element comprises approximately 500 km. The industry standard for such interconnectors is High Voltage Direct Current (HVDC), as was used for the East West Interconnector which EirGrid developed between Ireland and Wales. Converter stations at each end would be used to convert the electricity to enable it to be carried on the respective transmission networks.

EirGrid currently operates the existing East West Interconnector between Wales and Ireland, providing electricity to the Irish and UK electricity transmission networks.

The potential capacity of the Celtic Interconnector is estimated at approximately 700 megawatts (MW), enough to power 450,000 households.

What are the benefits of this project?

  • Importing and Exporting energy; 
  • Securing security of supply by providing a reliable high capacity link;
  • Increasing competition in the electricity market; and
  • Enhancing the flexible exchange of power flows with mainland Europe.


The Celtic Interconnector would also act as a piece of key, strategic infrastructure for Europe, by:

  • Supporting a single European Electricity Market;
  • Increasing interconnection between European Countries;
  • Facilitating Renewable Energy; and
  • Increasing Competition.