EirGrid

Interconnection

Interconnection connects our grid to neighbouring grids. This page gives details of the HVDC Interconnection on the island of Ireland.

illustration of planned interconnections

Why We Need Interconnection

Interconnection makes the system more resilient and efficient by connecting to neighbouring grids. This added strength will become increasingly important as renewable forms of generation grow.

Interconnection is a key component to achieving EirGrid Group’s 2020-25 Strategy. Part of this is connecting the grids of Ireland and Great Britain, and Ireland and mainland Europe through High Voltage Direct Current (HVDC) Interconnection. 
 

Our key areas of focus for interconnection are:

  • Asset management of the East West Interconnector (EWIC) for a safe and reliable asset
  • EWIC commercial operation in line with customer and market requirements
  • Develop the Celtic Interconnector with colleagues in the French TSO RTE
  • Exploring opportunities for further interconnection
  • Supporting the development of any new HVDC interconnection and ensuring operational readiness for connecting to the market and power system

East West Interconnector

EirGrid Interconnector DAC owns the East West Interconnector (EWIC). The EWIC links the electricity grids of the island of Ireland and Great Britain via submarine cables running between converter stations in Ireland and Wales.

It is a High Voltage Direct Current (HVDC) connection capable of providing capacity of 500 MW, flowing in both directions (import/export). It consists of approximately 260 kms of cable connecting Portan in Ireland to Shotton in Wales. 186 km of this cable is under the sea.

Safety

Safety is core to how we do business. To see if your proposed works are close to the interconnector route, please consult our safety notice and refer to the following links:

If you need any additional information, call +353 1 237 0924 (Ireland) or +44 1 244 288 353 (UK). In the event of an emergency relating to the East West Interconnector cables, EirGrid will be contacted immediately.

The Health and Safety Authority have published a Code of Practice (CoP) on avoiding danger from underground services. The CoP provides practical guidelines to ensure compliance with legal requirements.

Trading on the East West Interconnector

Forward trading arrangements and Financial Transmission Rights (FTR) on the SEM-GB border ceased on 31st Dec 2020 after Brexit took legal effect. The East West Interconnector (EWIC) does not offer FTRs at present.  

Interconnector capacity is exclusively offered in the intraday auctions between SEM and GB. The SEM Committee have completed a consultation on the cross-border trading arrangements. We await further direction from them.

Outage Information

Forced Outages

In the event of a forced outage of the East West Interconnector, the Allocation Platform shall notify the affected holders of Long-Term Transmission Rights as soon as possible of a curtailment of Long-Term Transmission Rights as per Article 57 of the HAR “Process and notification of curtailment”.

Planned Outages

Planned outages of the East West Interconnector are coordinated between EirGrid Interconnector DAC, EirGrid Plc, and National Grid Electricity System Operator.

For both forced and planned outages, REMIT messages must be published on a designated platform. REMIT (Regulation (EU) 1227/2011) is an EU obligation to ensure that inside information related to energy transactions is disclosed in a transparent manner.

EWIC publishes on Elexon’s Balancing Market Reporting System as a listed UK platform and JAO’s Inside Information Platform as a listed EU platform.

Relevant EWIC Documents

Below, you will find all key documentation relating to the East West Interconnector

Access Arrangements

Consultations

There are currently no open consultations. See details of previous consultations below.

Previous Consultations

Access Rules and Charging Methodology

EirGrid Interconnector DAC sought to consult on the Access Rules and Charging Methodology of the East West Interconnector (EWIC).

The purpose of this consultation was to invite the views of interested parties on the following:

  • Proposed rule changes that are required to transition to I-SEM, Financial Transmission Rights, and the Harmonised Allocation Rules
  • The continued applicability of the existing Moyle and East West Interconnector Access Rules and charging methodology up to the date of I-SEM go live

Documents relating to this consultation can be found below:

A section of the valve of the EirGrid East West Interconnector

Valve of the EirGrid East West interconnector

European Network Code Consultations Ireland-UK Long Term Capacity Splitting Rules

This consultation concerned the regional TSO proposal for the Long-Term Capacity Splitting Rules Methodology for the IU Capacity Calculation Region, in accordance with Article 10 of the Commission Regulation (EU) 2016/1719 of 26 September 2016 establishing a guideline on forward capacity allocation.

Interested market parties can access the consultation via the ENTSO-E Consultation Hub.

Ireland-UK Long Term Capacity Calculation

This consultation concerned the regional TSO proposal for the Long-Term Capacity Calculation Methodology for the IU Capacity Calculation Region, in accordance with Article 10 of the Commission Regulation (EU) 2016/1719 of 26 September 2016 establishing a guideline on forward capacity allocation.

Interested market parties can access the consultation via the ENTSO-E Consultation Hub.

EWIC Biodiversity Project

A biodiversity enhancement and action plan at the site of the EWIC station in Co Meath.

Contact Information

East West Interconnector

Tel: +353 (0)1 677 1700

Email: eastwestinterconnector@eirgrid.com

Joint Allocation Platform

Tel: +352 (0)27 62 38 38

Service desk: http://helpdesk.jao.eu

Email: helpdesk@jao.eu

EirGrid Main Reception

Tel: +353 (0)1 677 1700

Email: info@eirgrid.com

Emergency Number

Tel: +353 (0)1 237 0924

iso certificate

Celtic Interconnector

Part of our role is to explore and develop opportunities to interconnect the transmission grid with grids in other countries. The Celtic Interconnector is a planned subsea (undersea) link, allowing the exchange of electricity between Ireland and France. 

This would benefit electricity customers and markets in Ireland, France, and the EU.  

Since 2011, EirGrid has been working with its French equivalent Réseau de Transport d’Electricité (RTE) to find the best way to develop the interconnector. If built, the project is due to be completed in 2026.

Interconnector Market Arrangements

Multi-Regional Loose Volume Coupling

The Trade & Cooperation Arrangement (TCA) between the United Kingdom and the European Union sets out proposed trading arrangements to replace the UK’s membership of the Single Day Ahead Coupling (SDAC) market. 

Annex ENER-4 of the TCA sets out the broad requirement for this new market design. This is known as Loose Volume Coupling (LVC).

Under LVC, the volume and flow of interconnectors between the UK and EU bidding zones directly connected to the UK are determined independently from the pan-EU SDAC market process.

Other Interconnection

Moyle

The Moyle Interconnector links the electricity systems between Northern Ireland and Scotland. It is a 500 MW HVDC submarine interconnection. It connects Ballycronan More Substation in Islandmagee, Northern Ireland with Auchencrosh Substation in Ayrshire, Scotland. 

The Interconnector is owned and managed by Mutual Energy.

Greenlink

Greenlink is a HVDC interconnector currently under construction. It will link the electricity systems of Ireland and Great Britain via a subsea cable. The interconnector will run between Great Island substation in County Wexford, and Pembroke 400 kV substation in Wales.

The total length of the cable will be 200 km, with 160 km under the sea. The interconnector is expected to provide a 500 MW link. It is due to become operational in 2024.

Greenlink is privately owned by Greenlink Interconnector Limited.