How Ireland will benefit from the Celtic Interconnector
Sarah Rigney
Staff Writer

The Celtic Interconnector aims to increase Ireland’s supply of electricity by establishing a connection with France. Here we dive into all you need to know about the project.

The Celtic Interconnector will link France and Ireland’s electricity grids, allowing the two countries to exchange electricity through an undersea link.

With the project coming to fruition, we decided to take a look at how both Ireland as a nation and energy customers can benefit from the interconnector. 

We also delve into the timeline, recent developments, and explore why Ireland chose to partner with France.

What is the Celtic Interconnector?

Interconnection is a type of project that the EU is supporting to ensure the security of the supply of energy across Europe. 

The Celtic Interconnector is a proposed subsea (undersea) link between Ireland and France to facilitate electricity exchange by creating an electrical interconnection between the two countries. 

Due to be completed by 2026, the project aims to benefit electricity customers and markets in Ireland, France, and the EU.

The Celtic Interconnector has been in the pipeline since 2011 when EirGrid, Ireland’s electricity network operator, began working with its French equivalent Réseau de Transport d’Electricité (RTE) to discover the best way to develop the interconnector.

The interconnector will be the first direct energy link between Ireland and France (or indeed anywhere on the EU mainland) and it will run undersea for 500 km. 

It will run from the French north-west coast to Youghal, in Cork. There will be an additional 40 km of underground cable laid on land, from Ballyadam to a substation on the national grid at Knockraha.

At the moment, there are similar interconnectors between Ireland and Wales, Northern Ireland and Scotland, and also between many other countries across Europe.

Benefits for Ireland and France

The Celtic Interconnector will assist in the development of an integrated system for the European energy market, meaning electricity can move more efficiently to where it's needed.

The interconnector will bring many benefits to Ireland and France, and wider Europe:

1. Greater electricity supply

It will allow 700MW (megawatts) of electricity to move between France and Ireland. This is the equivalent of supplying power to around 450,000 homes. This is important as demand for electricity in Ireland (through the rise in the number of data centres as well as growth in the economy) is expected to increase hugely over the coming years.  

With a greater supply available, electricity costs for Irish households will hopefully be lowered. 

2. Facilitate an increase in the use of renewable energy

The connection between Ireland and France will increase the integration of renewable energy, at a European level. This in turn will aid Ireland and France in meeting their individual climate goals and targets.

3. Support the development of a more sustainable electricity mix

The interconnector will aid European objectives of a low-carbon energy future. It will help Europe in achieving its energy and climate objectives of affordable and sustainable energy for all.

4. Electricity supply security

Pooling resources will allow France and Ireland to both cope better with spikes in electricity consumption, demand issues, and contingencies. Ireland will be able to sell extra renewable energy to France while we'll also be able to import electricity when demand for it is high and renewable output here low. 

5. Enhance European solidarity in the energy sector

The interconnector project will serve as a benchmark project for European solidarity in the energy sector. It will allow Ireland to directly benefit from the European integrated electricity market and will be our only direct transmission link to another EU Member State.

6. Promote electricity movement in Europe

The Celtic Interconnector will allow European energy customers to benefit from a more open electricity market.

7. Help the local economy

Employment opportunities will arise during the construction phase of the project. Job opportunities won't just be limited to building sites though. The hospitality sector will also benefit through the provision of meals and accommodation for construction workers. 

Why is Ireland partnering with France?

EirGrid created a feasibility report in 2009 to determine whether creating an interconnector with France was a good option. 

It was reported that France generates a considerable amount of excess energy, primarily from nuclear, but also from an increasing amount of hydro sources and other renewables. 

Another reason for choosing to create an interconnector with France is because the French electricity grid is already heavily interconnected with neighbouring, surrounding countries. In this sense, France can be seen as part of the broader European market, acting as a doorway for Ireland.

The timeline of the project

The project is being broken up into four different phases:

  • 2014 - 2016: Feasibility phase
  • 2017 - 2018: Initial design and consultation phase
  • 2019 - 2021: Detailed design phase
  • 2022 - 2026: Construction phase

At the moment, the project is entering the construction phase.

Recent developments

In May 2022, An Bord Pleanála granted EirGrid and RTE planning permission for the onshore element of the Celtic Interconnector. 

It was originally estimated that the interconnector would cost €930 million. However, in November 2022 it was revealed that the cost jumped up by €670 million - 72% - to €1.6 billion.

The planning application for the connector included a complete Environmental Impact Assessment (EIA) Report and Natura Impact Statement.

An Bord Pleanála reviewed the proposal, the cable route, the converter station, and the network connection plans. The landfill in Youghal, where the cable runs from the sea to the converter station at Ballyadam, was also inspected. 

In November 2022, the final construction and finance arrangements for the Celtic Interconnector were signed off in Paris, with Taoiseach Micheál Martin stating construction would begin in 2023. Just weeks later in December, Eirgrid announced it will start digging trenches in East Cork from next spring for the Celtic Interconnector cables.

Eirgrid officials have maintained that communities living along the cable-laying pathline will experience as little disruption as possible. That being said, guidelines are being developed for the distribution of a €2.4m community fund, which will offer those impacted by the project compensation. 

How is the Celtic Interconnector being funded?

It’s estimated that the project will cost €1.6 billion. 

In Ireland, the development of the transmission system and interconnectors is not paid for by the State through budget allocations. As such, the interconnector is being co-funded by both EirGrid and RTE, with some co-financing from the EU. 

Ireland’s independent energy regulator, the Commission for Regulation of Utilities (CRU), and the French equivalent, Commission de régulation de l'énergie (CRE) agreed that 65% of the project’s estimated investment costs will be allocated to Ireland, with the remaining 35% allocated to France. This is based upon the breakdown of benefits to each country.

In 2019, the project was awarded €530 million from the European Commission’s Connecting Europe Facility (CEF).

How will the electricity be generated?

The Celtic Interconnector aims to reduce Ireland’s reliance on the burning of fossil fuels to generate electricity and to promote the integration of renewable energy production.

When Ireland has an excess supply of electricity generated from renewable sources, this will be exported to France. This will reduce dependence in France (and the wider European Union) on nuclear generation sources, in turn reducing the use of nuclear generation plants.

Electricity generated from nuclear facilities will be part of the imported electricity mix to Ireland, in the same way that it is currently imported as part of the electricity mix from the UK through the East-West Interconnector. 

With the Celtic Interconnector, the nuclear fuel used in the process of generating electricity remains in France and won’t be imported into Ireland.

Will a second interconnector be needed between Ireland and France? 

In July, the Institute of International and European Affairs (IIEA) released a paper suggesting that a second interconnector between Ireland and France will be needed.

The IIEA stated that a second interconnector is necessary to manage the security of supply and help keep consumer prices down. The additional interconnector would enable Ireland to export wind energy as the Irish wind economy grows across the next decade. 

Currently, however, there are no plans to develop another electricity interconnector between Ireland and France.

The East West Interconnector

Ireland has another interconnector already, the East West Interconnector, which links our electricity grid to Great Britain. 

Submarine cables are used and are run between converter stations in Ireland and Wales. This High Voltage Direct Current (HVDC) can provide a capacity of 500MW, through importing and exporting electricity.

Cut your energy costs today

Hopefully, households in Ireland will see a reduction in energy bills thanks to the Celtic Interconnector. However, there are still four years until we see the benefits first-hand.

If you want to cut your energy bills sooner than this, why not switch to a cheaper energy supplier?

Here on, we make it quick and easy to switch to a more affordable energy deal. With our free comparison and switching tool, you can review the best deals against your current supplier.

Discover the ins and outs of the comparison and switching process in our Quickstart Guide.

Are you looking to save more money? If so, try out our other comparison tools, which can help you save on broadband, insurance costs, and banking fees.

Let’s hear your thoughts

What do you think of the plans for the Celtic Interconnector? We’d love to hear from you! 

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