Moyle Interconnector
Cross BorderOperational500 MW250 kV63.5 km2002
Also known as:NESO TEC PRO-001292-1
Status:Operational
Capacity:500 MW
Project Company:
Moyle Interconnector Limited
Type:cross border
Website:www.mutual-energy.com
The Moyle Interconnector is a 500 MW high-voltage direct current (HVDC) subsea link between Scotland and Northern Ireland, connecting Auchencrosh (South Ayrshire) and Ballycronan More (Islandmagee, County Antrim). Configured as dual monopoles (2 x 250 MW) operating at a nominal DC voltage of 250 kV and nominal current of about...
Supply Chain (9)
Project Timeline (47)
11 Aug 2025Construction Other
By August 2025, Mutual Energy had completed installation of a 490‑panel, 190 kW peak solar photovoltaic array at the Moyle Interconnector converter site in County Antrim. Delivered by Dowds Group with support from Siemens, the on‑site solar system supplies low‑carbon electricity directly to the interconnector facility, reducing reliance on grid power and forming part of Mutual Energy’s wider programme to decarbonise operations and support Northern Ireland’s transition to a low‑carbon energy system.
15 Nov 2022System Testing
By November 2022 Mutual Energy, working with Siemens Energy and technical advisor TransGrid Solutions, completed a multi-year refurbishment and upgrade of the Moyle Interconnector’s control and protection systems at both converter stations, including two years of design and manufacturing, a year of factory testing in 2021, and on-site works and commissioning in 2022, installing new controls, communications and operator interfaces with advanced cyber protection while maintaining about 50% interconnector capacity during the project.
6 Nov 2022Geophysical Survey Complete
In an October 2022 progress update, AWJ Marine stated that the offshore portion of the marine geophysical survey over the Moyle Interconnector cables, the Scotland to Northern Ireland Pipeline, and the Larne and Belfast Lough crossing pipelines was expected to conclude on 6 November 2022. The update noted that most of the offshore work by the vessel Noordhoek Pathfinder was already completed and that all dates were subject to weather and sea conditions.
Sept 2022Geophysical Survey Start
AWJ Marine reported that a marine geophysical survey campaign over both Moyle Interconnector cables, the Scotland to Northern Ireland Pipeline, and the Larne and Belfast Lough crossing pipelines in the North Channel started in September 2022. By 24 October 2022, the nearshore component from the shore to 15 m water depth, conducted by the vessel Deep Marker, had been completed, while the offshore component was ongoing, being carried out by the vessel Noordhoek Pathfinder.
1 Apr 2022Capacity Upgrade
From 1 April 2022 the firm export limit on the Moyle Interconnector was increased to 400 MW, within an overall operating constraint band of -400 MW to 442 MW, improving its export capability from Northern Ireland to Scotland compared with earlier limits while still remaining below the technical 500 MW rating.
2022Construction Other
In 2022, Mutual Energy completed a major refurbishment of the Moyle Interconnector’s HVDC control system, working with Siemens Energy and other partners. Following two years of design and manufacturing and a year of factory testing in 2021, new control and protection equipment, communications and operator interfaces with advanced cyber protection were installed and commissioned, enhancing the link’s operational reliability, security of supply and ability to provide ancillary grid services between Scotland and Northern Ireland.
18 Jun 2020Converter Supplier Selected
On 18 June 2020, Siemens Gas and Power (Siemens Energy) was awarded a project by Mutual Energy to refurbish the Moyle Interconnector’s HVDC control and protection system at Ballycronan More and Auchencrosh, including detailed design, manufacturing, testing, installation, commissioning and provision of a control training simulator, to modernize and enhance the 500 MW link’s operation.
28 Sept 2018Geophysical Survey Complete
For the 2018 marine geophysical investigations over the Moyle Interconnector cable and the Scotland to Northern Ireland Pipeline in the North Channel, AWJ Marine’s notice indicated that nearshore survey activities were scheduled to be completed by 28 September 2018, with offshore work expected to finish by 18 September 2018. These timelines defined the planned completion of that geophysical survey campaign.
14 Aug 2018Geophysical Survey Start
AWJ Marine announced that marine geophysical survey work would commence in August 2018 along the route of the Moyle Interconnector cable and the Scotland to Northern Ireland Pipeline in the North Channel between Northern Ireland and Scotland. The notice stated that nearshore survey operations were due between 14 August and 28 September 2018, and offshore survey work from 24 August to 18 September 2018, to be carried out by the vessels MV Titan Discovery and Geosund.
~Dec 2017Cable Installation CompleteStale
Moyle Interconnector Ltd planned that full delivery of an EPC contract to design, manufacture, supply, install, joint and commission two new medium-voltage cables (replacement return conductors) between the existing HVDC converter stations at Auchencrosh and Ballycronan would be completed before the end of 2017.