Celtic Interconnector

The Celtic Interconnector project will create an electrical interconnection between Ireland and France to allow the exchange of electricity between the two countries. 

It is being developed with EirGrid and our French equivalent Réseau de Transport d’Electricité (RTE) and will be the first interconnector between Ireland and continental Europe.

The Celtic Interconnector will travel from east Cork to the north-west coast of Brittany.

The project is co-funded by EirGrid and RTE. In 2019, it was awarded €530.7 million from the European Commission’s Connecting Europe Facility (CEF). 

Some EU funding was also received as a Project of Common Interest (PCI). A PCI is an infrastructure project that links the energy systems of EU countries. It gives the project enhanced status, as well as more efficient access to planning permission and permits.

You can keep up with the latest developments in the Updates section below, and you can also read a round-up of major developments in our quarterly newsletters, which will bring you up to date on the works in Ireland and in France, community benefit and other topics related to the delivery of this strategic energy project. 

When built, the Celtic Interconnector will bring many benefits for Ireland, France, and the EU. It will:

The Celtic Interconnector is part of developing an integrated energy system for Europe. A fully integrated energy market will help the EU to:

High Voltage Alternating Current Electricity Cable (HVAC) and High Voltage Direct Current Electricity Cable (HVDC) Land and Submarine Circuits

Ireland and France both use HVAC technology to move electricity around their networks and supply consumers.

However, different technology is needed to transfer electricity at long distances: HVDC. This is the industry standard for long distances.

For this project the following circuits will be used to transport electricity:

The HVDC interconnector between Ireland and France will be about 575km long. This includes the subsea and the onshore cable to the converter station. The cables for the HVAC and HVDC are all underground.

Converter Stations

Converter stations will be built in each country to change the electricity from HVDC to HVAC, and the other way around. After it is converted from HVDC to HVAC technology at the converter station, the electricity will be transferred to the existing substations in each country. 

Network Connection

Two existing substations were identified as the best locations to connect to the transmission system in each country. The existing stations are located at:

You can see the main elements of the proposed infrastructure in Ireland in the graphic below.

We use a six-step approach to developing projects to improve the grid. You'll see these steps mentioned across our project plans. As part of our six-step approach to developing projects, we ask for regular feedback from the public and other stakeholders. The steps indicate how far along we are in a project. Our 'Have Your Say' document explains these steps in more detail.

The European Union has partly funded the Celtic Interconnector and designated it as a Project of Common Interest (PCI). 

A PCI is an infrastructure project that links the energy systems of EU countries. 

It gives the project a higher status, allows more efficient access to planning permission and permitting processes.

As a PCI the Celtic Interconnector also has access to financial support from the Connecting Europe Facility (CEF) – a fund to develop Europe’s energy, transport and digital networks.

The Celtic Interconnector Community Forum brings together people and organisations from across the project area so that stakeholder and community views can be discussed, understood and properly considered prior to and during project delivery. This community forum will create the opportunity for dialogue between stakeholders with diverse and direct interest in the project and the EirGrid project team.

Irish Rural Link has been appointed as the community forum's independent facilitator.

Irish Rural Link (IRL), formed in 1991, is a national network of organisations and individuals campaigning for sustainable rural development in Ireland and Europe. IRL, a non-profit organisation, now directly represents over 600 community groups with a combined membership of 25,000. The organisation has a long, successful track record in designing and implementing community relations plans for development companies, community organisations, semi-state agencies and Government. 

The purpose of the forum is to ensure that stakeholder and community views are understood and properly considered prior to and during project delivery. The group will provide a forum for dialogue between stakeholders with interests in the project and the project team. Community Forum members will also be invited to input on the design and implementation of the Community Benefit Fund.

Communications

To help forum members share information with their community please see the resources below:

Social media notice

This notice provides the Celtic Free Text registration information and is designed for use on WhatsApp, Facebook and other social media platforms. This can be downloaded, saved to and sent from your smart phone. 

To save it to your phone, simply press and hold the image until a menu pops up, and choose the appropriate action. To save it on a computer, right-click the picture and choose "Save image as".

Poster

This is a downloadable and printable poster encouraging people to register for updates on the Celtic Interconnector.

The €2.4 million Celtic Interconnector Community Benefit Fund has been established by EirGrid. Communities play an important role in facilitating grid infrastructure, as we work towards achieving our climate ambitions.

The fund recognises the importance of local communities who support this work. It also recognises the temporary disruption which may be caused within proximity of the cable line during the construction phase of the project.

The overall aim is to increase public and environmental wellbeing in the community and to leave a positive legacy in the communities hosting EirGrid infrastructure.

Successful applicants to the first round of funding include sports clubs upgrading their facilities, community councils, walkways, arts initiatives, and schools. 

December 2024

The next phase of works critical to the progress of the Celtic Interconnector at Claycastle beach, Youghal will commence today Tuesday 3 December.

The works will begin with the establishment of a work site in a section of the car park at Claycastle beach. 

During the works, access to the beach, boardwalk and car park will be always maintained, with occasional pedestrian walkway diversions. 

There will be a temporary reduction of 70 car parking spaces during the works and some disabled parking bays will be relocated. 

Once the work site has been established, the next phase of works will be the building of a cofferdam on a section of the beach leading from the car park to the water. 

This cofferdam is an open-ended enclosure where construction works will take place when the tide is out.  

This cofferdam is for laying the ducts required for the passage of the cables to and from the marine route to France. 

This work is scheduled to start on 9 December, in preparation for the installation of ducting in the cofferdam in 2025. 

Once all works are completed, the beach will be restored to its original condition. 

Details on the works and the work schedule can be seen in the presentation below.

November 2024

Our fifth Celtic Interconnector Community Newsletter is now available. 

This newsletter will bring you up to date on the current works in Ireland and France, including steel works and cable installation, community benefit funding and other topics related to the successful delivery of this strategic energy project.

September 2024

Update on Roadworks Friday 27 September

The latest roadworks update on-land cable works for the Celtic Interconnector is that Nexan’s subcontractor, Sorensen, continue to install ducting and joint bays to facilitate the subsequent installation of cabling along the N25 in east Cork – the first section being from Churchtown Junction (North) to Castlemartyr. 

They are now 75% complete with their work on this section of the N25 and would like to thank residents and drivers for their patience and cooperation.

On Section I (Road Number R-626 – Ballyedmond, Carrigogna, Midleton), they have completed Phase One, and we will be moving on to Phase Two from Monday 30 September.

Please see below road closure for Phase Two shown in RED with diversion routes in GREEN and ORANGE.

Work commenced this week to increase the capacity of an existing culvert in Ballyspillane. These remedial works were deemed necessary to reduce the risk of future flooding. 

Reinstatement of this road section will continue for the week and the road will be open by Friday 4 October.

Reinstatement work will also continue on Woodstock Hill with the team backfilling the final joint bay. It is expected that traffic lights will be removed by the end of week commencing Monday 7 October.

Please note: 

August 2024

Our fourth Celtic Interconnector Community Newsletter is now available. 

This newsletter will bring you up to date on the current works in Ireland and France, including works in the marine, community benefit funding and other topics related to the successful delivery of this strategic energy project. 

July 2024

Over 90% of the 400 kV AC cable trenching and ducting is now complete and works are under way on the 320 kV DC cable trenching and ducting. 

Joint bays are installed with passing bays in place to facilitate traffic flow while cable pulling and jointing takes place, bringing work on the local roads closer to completion with every week.

At the converter station site at Ballyadam, near Carrigtwohill, Siemens Energy and its sub-contractors have recently completed the enabling and earthworks phase and have now mobilised for the main civil works phase at the site.

Works have also commenced at the newly-named Gogganstown 400 kV substation, which will be located adjacent to the ESB Knockraha 220 kV substation. 

This is a single-bay substation, to facilitate connection to the existing Knockraha substation, where the 400 kV electrical connection from the interconnector will be transformed down to 220 kV for connection into the transmission network.

June 2024

In partnership with SECAD Partnership CLG, EirGrid hosted a public webinar on biodiversity to share information with communities interested in applying for the next phase of funding from the Celtic Interconnector Community Benefit Fund, through the fund's biodiversity stream. 

Expert advice was provided by SECAD’s WildWork ecologist, William O’Halloran, who shared his experience and insight into what is involved in developing community biodiversity projects.

The excellent panellists from Harpers Island Wetlands, Cobh Tidy Towns and Cabragh Wetlands were generous and engaging in telling their own community stories and how they overcome the challenges they face, from recruitment of volunteers, to planning the project and raising the funds required. 

Most importantly they were enthusiastic in their encouragement urging communities to pursue their projects and reach out for help.

You can find the presentation slides from the webinar or view a recording of the event below.

May 2024

Our third Celtic Interconnector Community Newsletter is now available.

The newsletter will bring you up to date on the works in Ireland and in France, current works on the project, community benefit and other topics related to the delivery of this strategic energy project. 

April 2024

Cable Construction Information Events

Works have commenced in the east Cork area, and road closures for the work may impact you.

As part of ongoing information and engagement activities, two cable construction information sessions will be held at The Midleton Park Hotel, Midleton, to keep people up to date on the works.

They are taking place on Tuesday 9 April, from 4pm to 6.30pm, and Wednesday 10 April, from 6pm to 8pm. 

You can read more about the events here.

March 2024

An archaeological investigation to explore the extent of remains of a petrified forest under Claycastle Beach in Youghal will commence on Monday, 11 March.

The minor investigation will consist of a test pit on the beach and will be overseen by archaeologists from the Underwater Archaeology Unit and the National Monuments Service.

It is expected the investigation will last four days, concluding on Thursday, 14 March. 

February 2024

Our second Celtic Interconnector Community Newsletter is now available.

The newsletter will bring you up to date on the works in Ireland and in France, current works on the project, community benefit and other topics related to the delivery of this strategic energy project. 

Now that works have commenced, we look forward to continuing to keep you up to date with this quarterly newsletter.

January 2024

Section 146B request

A Section 146B request for alteration was recently made to An Bord Pleanála by EirGrid. This request is for the creation of a permanent vehicular access to the Cable Sealing End (CSE) compound which is to be situated immediately to the east of the existing Knockraha 220kV substation.

The details of the request and public consultation can be read at www.eirgridcelticinterconnector.ie on the Section 146B Modification page.

The public consultation period will open on Thursday 1 February and run for four weeks, closing on 28 February 2024.

Road Closure Licence Application

As part of the roadworks programme, Sorensen has now applied to Cork County Council for a temporary full road closure licence for Road Number L-7634 to Hagerty’s Cross/Upper Garranes. 

This is referred to as Section C in the Road Closure section map. 

The application is for a temporary full road closure licence from 6am on Friday 1 March to 6pm Friday 31 May.

For more information please see the Road Closure Updates section.

Work recommences

Following the Christmas break cable road works recommenced in Section B – Ballinakilla L-7631 and Section E - Woodstock Hill – L-3606 in January 2024. 

For additional information on cable sections and associated works please see Road Closure Updates.

Pre-work activities for work at Ballyvergan Marsh, Youghal are taking place from Monday 22 January for approximately four weeks.

These works can include trial holes, slit trenches and surveys as well as site clearance works, in preparation for the proposed trenching and ducting for the cable installation.

To facilitate the safe works, Sorensen will have traffic management in place on the R633 and Front Strand Road as outlined below from Monday 22 January for about four weeks. 

Temporary Entrance to the Marsh is outlined below in BLUE. 

Access will be maintained in the area at all times and Sorensen will make every effort to minimise any disruption to residents, businesses, and the public along the route during the cable works.

To register for FREE text updates on road closures please text INTER to 50015

Installation of underground cable

The cable installation animation above demonstrates the different stages of work required when installing underground cable.

Stage 1 – Preparation of the cable route

This starts with the excavation of the cable trench in the road, the installation of cable ducts and the installation of passing bays in preparation for future construction works.

To ensure the health and safety of workers and facilitate progress, this work requires temporary road closures on non-national roads. 

Once the preparatory cable route work is completed the final step is to install joint bays in the road.

At this final step, the use of the pre-installed passing bays will eliminate the need for road closures.

Once completed the road is reinstated.

Stage 2 - Cable installation and associated works

At this stage, the cable is pulled through the pre-laid ducts. This work happens in the area of the joint bays. 

During this time traffic can again use the passing bays, eliminating the need for road closures.

Stage 3 - Jointing of cable sections

This involves detailed joining work to be carried out inside the joint bays. Again, the installed passing bays eliminate the need for road closures.

The final road surface reinstatement and removal of passing bays is then completed.

Temporary road closures will again be required at this final step on non-national roads, although the closures required will be limited with only areas around the joint and passing bays requiring reinstatement. 

Celtic Interconnector

On-land cable works (trenching and ducting) for the Celtic Interconnector project commenced in November 2023. 

The work began at Knockraha substation and is progressing towards Carrigtwohill; from Carrigtwohill it continues easterly on local roads to Churchtown Junction (North), where the cable enters onto the N25. 

Work on the N25 will be completed in sections to facilitate traffic movements. 

Local and emergency access to affected roads will continue at all times and every effort will be made to minimise disruption to residents, businesses, and the public along the route during the cable works. 

N25 - Celtic Interconnector

Sorensen will be installing ducting to facilitate the subsequent installation of cabling and joint bays along the N25 between Churchtown Junction (North) and Youghal with large sections going off road around the villages of Castlemartyr and Killeagh.

The first phase of these works on the section of the N25 from Churchtown Junction (North) to Castlemartyr is now completed.

The second phase from the east of Castlemartyr to Killegah has now begun.

Access to properties will be maintained at all times.  

Please note that for the duration of the works a Roadworks Speed Limit Order has been made, reducing the speed limit on this road section to 60km/h. 

Road Closure Licences Information

A process of temporary road closures, under licence from Cork County Council, is in place as required on local roads. 

The map below illustrates the local road sections between Knockraha to Churchtown Junction (North) for which temporary road closure licences will be applied for over the course of the work.  

End-to-end sections will not be completed at the same time to facilitate better traffic movement. 

Road closure sections map - Knockraha 220 kV substation to Churchtown Junction (North)

Trenching and ducting works are taking place on the N25 from Churchtown Junction (North) to Castlemartyr, with speed restrictions of 60 km/h in place.

Register to receive project updates and newsletters by email at  celticinterconnector@eirgrid.ie

Below are documents about the Celtic Interconnector. We have organised the documents depending on which stage (step) of the project they refer to in EirGrid’s Six Step Process for developing projects in Ireland. 

They are listed in order from most recent to earliest. You can also search for 'Celtic Interconnector' in our Publications section for all related documents.

EirGrid plc’s Strategic Infrastructure Development application to An Bord Pleanála for the Celtic Interconnector Project is available to view on this website

Step 6 Documents

EirGrid & SECAD Partnership Community Biodiversity Webinar

Step 5 Documents

Step 4 Documents

Step 4 Maps

Step 3 Documents

Step 2 Documents

Step 2 Land Reports

Health

​Project of Common Interest Process

Celtic Interconnector Community Forum

Terms of Reference

Community Forum Minutes of Meetings

Community Forum Presentations