Greenlink is a proposed 500 megawatt (MW) subsea and underground cable electricity interconnector (with associated converter stations) between the existing electricity grids in Ireland and Great Britain (GB), allowing for electricity to flow both ways between the two countries. Greenlink will provide a new grid connection between EirGrid’s Great Island substation in County Wexford (Ireland) and the National Grid’s Pembroke substation in Pembrokeshire (Wales).
Greenlink has key strategic importance. The construction of the interconnector will deliver: increased energy security, regional investment and value for money to consumers; and will enable the further integration of low carbon renewable energy.
Greenlink has been awarded Project of Common Interest (PCI) status, making it one of Europe’s most important energy infrastructure projects and granting it the “highest national significance” possible.
Greenlink will consist of two converter stations - one located close to the Great Island substation in County Wexford and the other close to the Pembroke substation in Pembrokeshire - connected by two High Voltage Direct Current (HVDC) cables under the Irish Sea. A converter station converts electricity from Alternating Current (AC) to Direct Current (DC) and vice versa.
DC electricity is typically used for the transmission of electricity over long distances because it has lower losses, negligible heating effects and is therefore suitable to be buried underground. Accordingly, there will be no overhead lines between the two converter stations. Onshore, the cables will be buried underground and offshore the cables will be buried in the seabed or laid on the seabed with protection, if burial is not practicable.
Greenlink is planned for commissioning in 2023.
The project will require planning permission in Ireland and Wales. Constructing and commissioning an interconnector requires the completion of a thorough programme of environmental and technical assessment to ensure that the final interconnector design fully considers the environment in which it is built. Greenlink Interconnector Limited will undertake a voluntary Environmental Impact Assessment (EIA), which will result in the application documents facing an increased level of scrutiny from stakeholders.