Moyle Interconnector Cable

The Moyle Interconnector Cable links the electricity grids of Northern Ireland and Scotland, running for a distance of 63 km between converter stations at Ballycronan More in Island Magee, County Antrim and Auchencrosh in Ayrshire. The link consists of two separate integrated return conductor (IRC) cables (a north and south cable), each with a high voltage (HV) and a low voltage (LV) return conductor integrated into a co-axial design.  Following repair work in 2015, two additional low voltage cables have been laid alongside the original cables.

The system has been operational since 2002. Some problems arose with the cable after 2010 (as a result of a failure in the low voltage polyethylene integrated return conductor (IRC) insulation). This meant that the interconnector could only run at half of its 500MW capacity.  In response Moyle Interconnector Limited commissioned a repair, called the “Moyle Returns Cable Project”.

Cable repair: Moyle Returns Cable Project

Moyle Cable Route March 2015

Moyle Cable Returns Route

During 2015 the Moyle Interconnector was successfully restored to full operational capacity by installing two new return conductor cables.  These cables run close to the route of the existing north and south cables (see figure here).

The route for these two cables was selected after bathymetric, seismic and ROV surveys of the seabed, to optimise cable burial & protection.

Facts and Figures

The Moyle Interconnector provides a vital link between the electricity market in Ireland and the market in the UK and Europe, providing access to economical and reliable electricity supplies for Northern Ireland.

The installation of the cable followed more then 10 years of survey work and feasibility studies.  The cable was installed on the seabed in 2001 and came into operation in 2002.  It provides a capacity of 500MW of electricity, and was designed to be equal to the largest projected infeeds to the Irish electricity system for many years.

Project updates

Construction and operational updates for the Moyle Interconnector Cable and Moyle Returns Project are posted on this website.  You can read past updates below, and you can sign up for project updates to be delivered straight to your Inbox on our News Subscriptions page.  It’s quick, easy, free and secure.

If you have any queries about the Moyle Interconnector Cable, please contact us.

Updates (chronological list, newest first)

Moyle Interconnector: Cable Repair, August-September 2017

Mariners are advised that the vessel Nexans Skagerrak is being mobilised to carry out repair work on the southern Moyle Interconnector power cable in the North Channel between Northern Ireland and Scotland.  This work is due to commence on the 25th … Continue reading

Moyle Interconnector: Cable Repair, May 2017

Mariners are advised that the vessel Elektron is being mobilised to carry out emergency repair work on the southern Moyle Interconnector power cable in the North Channel between Northern Ireland and Scotland.  This work is due to commence on the … Continue reading

Moyle Returns Project: Rock Protection Update, 5th July 2016

This is a further update on rock protection work on the Moyle Returns Cables in the North Channel of the Irish Sea.  A brief update on survey works on other cables and pipelines in the North Channel, Belfast Lough and Lough Larne … Continue reading

Moyle Returns Project: Rock Protection Update, 16th June 2016

This is a further update on rock protection work on the Moyle Returns Cables in the North Channel of the Irish Sea.  A revised Notice to Mariners was issued for this work in October 2015 and can be downloaded Continue reading

Moyle Returns Project: Rock Protection Update, 1st June 2016

This is an update on progress with the rock protection work on the Moyle Returns Cables in the North Channel of the Irish Sea.  A revised Notice to Mariners was issued for this work in October 2015 and can be downloaded Continue reading

Moyle Returns Project: Rock Protection Update, 15th December 2015

This is an update on progress with the rock protection work on the Moyle Returns Cables in the North Channel of the Irish Sea.  A revised Notice to Mariners was issued for this work in October and can be downloaded Continue reading

Moyle Returns Project: Rock Protection Update, December 2015

This is an update on progress with the installation of the Moyle Returns Cables in the North Channel of the Irish Sea.  A revised Notice to Mariners was issued for this work in October and can be downloaded Continue reading

Moyle Returns Project: Installation Update, 26th October 2015

This is an update on progress with the installation of the Moyle Returns Cables in the North Channel of the Irish Sea.  A Notice to Mariners has previously been issued for this work, detailing the route and construction schedule.  A … Continue reading

Moyle Returns Project: Installation Update, 12th October 2015

This is an update on progress with the installation of the Moyle Returns Cables in the North Channel of the Irish Sea.  A Notice to Mariners has previously been issued for this work, detailing the route and construction schedule.  A … Continue reading

Moyle Returns Project: Update – nearshore rock placement, Scottish landfall

This notice provides a further update on progress with activities for the rock protection of the nearshore sections of the Moyle Interconnector cables.   This work started recently, and progress is summarised briefly below.

Nearshore Rock Placement, Scottish Landfall

On the … Continue reading