EirGrid

North South Interconnector

The North South Interconnector project will see the addition of a new 400 kV overhead line to the network, connecting the electricity grids in Ireland and Northern Ireland.

As the status of the project progresses, this webpage will provide the latest updates and information, as well as all relevant brochures, documents and community engagement details. In the event that you have a query which is not covered in our FAQ section, you can reach out to our project team via the contact information below.

Project Overview

Peer organisations EirGrid and SONI operate the electricity grid across the island, in Ireland and Northern Ireland respectively. Currently there is only one interconnector between the two jurisdictions. A problem on this interconnector could result in widespread power failures. 
 
As things stand, we have to restrict the amount of power that can flow through the existing infrastructure in order to limit the possibility of any such issues arising.  

The levels available at present are well below the secure and sustainable supply which the increase in demand for electricity requires. 

This project will allow us to: 

  • Eliminate the risk of a single event resulting in widespread power failures
  • Remove restrictions on cross-border flows of electricity
  • Bring more renewable energy onto the all-island grid
  • Operate a more efficient and cost-effective electricity grid  

The North South Interconnector will connect the electricity grids of Ireland and Northern Ireland and will run for approximately 138 kilometres, starting in County Meath and following through Counties Cavan, Monaghan and Armagh to County Tyrone.   

The North South Interconnector has been fully approved by the planning authorities in the Republic of Ireland and Northern Ireland. It was fully validated by the courts in both jurisdictions following a number of challenges.   

The electricity grid in Northern Ireland is managed by the System Operator for Northern Ireland (SONI). Details on the Northern Ireland section of the interconnector can be found on SONI's website. 

North South Interconnector graphic

Benefits of the Project

The delivery of the North South Interconnector will support national and regional economic growth and a resilient society.    

  • Robust electricity infrastructure that is fit for purpose and can drive inward investment and employment in the region and beyond.       
  • The project will improve the security of electricity supply and allow for more renewables to be integrated on the grid and transported across the island.     
  • A dedicated Community Benefit Fund will be made available to provide direct benefits to those communities living near the project infrastructure in Counties Cavan, Monaghan and Meath   
  • The North South Interconnector has been identified by the Government’s Accelerating Infrastructure Taskforce as a priority infrastructure project.  

Where Are We Now?

We are now at Step 6 - construction, energisation and benefit sharing.

The North South Interconnector has full planning and legal consent in both Ireland and Northern Ireland.  

Project Updates

March 2026  

EirGrid has written to landowners along the route of the North South Interconnector project in respect of the placing of infrastructure on or across their lands.  

The letters provide an update on the project and outline a revised compensation proposal and next steps.  

The letters issued follow an extensive engagement process carried out over the last number of years by EirGrid with landowners, and are the next step in our engagement process towards the construction of the project. 

ESB has also written to landowners over whose lands access is needed to facilitate the construction of the project. 

Frequently Asked Questions

General Contact

Post: North-South 400 kV Interconnection Development Project Manager EirGrid plc. The Oval 160 Shelbourne Road Ballsbridge Dublin 4 Ireland Email: northsouth@eirgrid.com Phone: Lo-Call 1890 252 690 (9am-5pm Mon - Fri)

North South Interconnector Planning Documents