Celtic Interconnector

As Ireland’s state-owned transmission system operator (TSO), EirGrid is statutorily obliged to explore and develop opportunities for further interconnection. We carry out studies and assessments on an ongoing basis of potential opportunities for interconnection for Ireland. In 2009, the ‘Interconnector Economic Feasibility Report’ identified an interconnector with France as one such opportunity.

The Celtic Interconnector is a proposed electrical link, which if built will enable the movement of power between Ireland and France. We have been working with our counterpart in France, Réseau de Transport d’Electricité, to investigate the feasibility of an electrical link between our two countries.

A series of joint studies into the feasibility of the interconnector have been carried out with the French TSO Réseau de Transport d’Électricité (RTE) since 2011. These studies have indicated that if built, an interconnector between the two countries would be beneficial for electricity customers in Ireland, France and the EU.

As part of the feasibility study, potential routing between the south coast of Ireland and the north-west coast of France was considered for the Celtic Interconnector.  The length of the subsea cable would be approximately 500 km. The total length of the interconnector between the two countries would be approximately 575 km.

The industry standard for such interconnectors is High Voltage Direct Current (HVDC), as was used for the East West Interconnector (EWIC) which EirGrid developed between Ireland and Wales. Converter stations at each end would convert the electricity back to High Voltage Alternating Current (HVAC).  This conversion is needed as, Ireland’s transmission system relies on HVAC technology to move electricity around the country.   

What are the benefits of this project?

If built the Celtic Interconnector will bring many benefits, including:

  • Ability to import and export 700 MW (megawatts) of electricity, the equivalent of supplying power to around 450,000 homes
  • Enhanced security of supply for Irish electricity users. It will provide Ireland’s only direct energy connection to an EU Member State once the United Kingdom leaves the EU
  • Apply downward pressure on the cost of electricity to consumers in Ireland
  • Help facilitate Ireland’s transition to a low carbon energy future
  • Provide a direct fibre optic communications link between Ireland and France.

Project of Common Interest

The European Commission views interconnection as key to a more integrated European electricity system with the aim of completing the European energy market, as it improves the movement of electricity around the system to the places that need it. In turn this is seen as important in order to help the EU achieve its energy policy and climate objectives of affordable, secure and sustainable energy for all citizens, as well as the long-term decarbonisation of the economy. Interconnection also allows electricity to be exported to markets and users in other countries.

The European Commission has designated the Celtic Interconnector as a Project of Common Interest (PCI). PCIs are key infrastructure projects, especially cross-border projects that link the energy systems of EU countries. Read more about the Celtic Interconnector as a PCI project here.

PCI projects can also benefit from accelerated planning and permit granting and also have access to financial support from the Connecting Europe Facility (CEF). The Celtic Interconnector has already been supported with over €3.5m provided for the Feasibility Phase of the project and a further €4m allocated to the Initial Design & Pre-Consultation phase of the project. EirGrid and RTE made an application in June 2019 for financial support under the CEF to cover the detailed design and construction of the Celtic Interconnector. In October 2019 it was announced that we had received €530 million of funding from the European Commission. EirGrid welcomed this decision and we look forward to engaging regularly with the public and other stakeholders as the project progresses.

What does the Celtic Interconnector consist of?

The Celtic Interconnector will enable the transfer of electricity between Ireland and France. A fibre optic cable will also be installed, facilitating enhanced telecommunications capacity with continental Europe. The main elements of the proposed infrastructure in Ireland are illustrated in the graphic below.