Interconnection
Interconnection connects our grid to neighbouring grids. This page gives details of the HVDC Interconnection on the island of Ireland.
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:
- ROI B-4-U-DIG
- UK Line Search Before-U-Dig
- Irish Route Map (PDF, 7.2 MB)
- Wales Route Map (PDF, 7.8 MB)
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
Licences
- EIDAC Electricity Interconnector Operator Licence (Ofgem) (PDF, 137 KB)
- EIDAC Electricity Interconnector Operator Licence (CRU) (PDF, 288 KB)
Access Arrangements
- EU Harmonised Allocation Rules (PDF, 470 KB)
- EWIC Access Rules V 5.0 (PDF, 255 KB)
- EWIC Access Rule V4.1 (PDF, 1,023 KB)
- EWIC Charging Methodology V3.0 (PDF, 190 KB)
Approvals
- HAR Rules Approval – CRU (PDF, 220 KB)
- HAR Rules Approval – Ofgem (PDF, 220 KB)
- HAR Rules Approval – ACER (PDF, 220 KB)
- CER Access Rules Approval (PDF, 191 KB)
- EWIC Access Rules & Charging Methodology Approval – Ofgem Access Rules Approval (PDF, 223 KB)
- Single Allocation Platform (SAP) methodology and the SAP Cost Sharing methodology decision – Ofgem Decision, 13th October 2017 (PDF, 192 KB)
- Single Allocation Platform (SAP) methodology and the SAP Cost Sharing methodology decision – CRU Decision, 25 October 2017 (PDF, 119 KB)
Interconnector User Forum
- East West and Moyle Interconnector Customer Conference 2018 (PDF, 8.7 MB)
- Asset Management Policy (PDF, 59 KB)
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:
Publications
A section of the 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
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.