MaresConnect is included in ENTSO-E’s Ten-Year Development Plan, recognising the project’s key contribution to realising Europe-wide goals related to energy policy and climate change.

Regulation - MaresConnect

Regulatory Support

Great Britain

In its Energy White Paper published in December 2020, the UK Government committed to a target of at least 18GW of interconnection by 2030, an increase of almost 10GW on the current level of 8.4GW.

In Great Britain, MaresConnect is seeking a Cap & Floor regulatory model from Ofgem in its current Third Cap & Floor Window. On 24 February 2023 Ofgem confirmed that MaresConnect met the eligibility criteria for  Window 3. Ofgem’s assessment of the Window 3 projects is ongoing, with a final decision expected over the summer 2024.

Ofgem granted MaresConnect an interconnector licence on 22 June 2022.


In July 2023, Ireland’s Department for the Environment, Climate and Communications (DECC) released its National Policy on electricity interconnection. The policy supports the establishment of additional interconnector capacity between Ireland and Great Britain and requires the projects with the most realistic prospects of delivery by 2030 to be progressed as soon as possible. In addition, Action 13 of Ireland’s Energy Security Package envisages the successful completion and integration of additional electricity interconnectors by 2030.

In December 2023, DECC published its draft updated National Energy and Climate Plan for 2021-2031, naming MaresConnect as the Ireland-GB interconnector project with the most likely prospects of connecting by 2030.

MaresConnect is seeking a Cap & Floor regulatory model from the Commission for Regulation of Utilities for Cap & Floor regulation in Ireland. Cap & Floor regulation has been successfully implemented in Ireland for the Greenlink Interconnector project.

The CRU has confirmed it will commence its initial project assessment of MaresConnect in Q2 2024, with a minded-to decision for public consultation expected by the end of 2024 and a final decision early 2025.

The CRU issued a direction to EirGrid in January 2024 to assess a grid connection for MaresConnect in Ireland.

UK – Ireland Energy Memorandum of Understanding

In line with the UK Government 18GW target and the commitments under the DECC National Policy, the UK and Irish Governments signed a memorandum of understanding in respect of the energy transition (Energy MOU) on 11 September 2023. The Energy MOU is intended to deepen the relationship between the two countries and enable closer work on important energy priorities, including electricity interconnection.

MaresConnect as part of ENTSO-E’s Ten Year Development Plan

ENTSO-E’s Ten-year network development plan (TYNDP) serves as the comprehensive plan for infrastructure development in Europe. It connects, facilitates, and complements national grid development plans, providing a holistic view of the future power system. It details how power links and storage could contribute to a cost-effective and secure energy transition. The TYNDP is essential to the timely and effective development of transmission infrastructure to deliver long-term European policy and aspirations.

ENTSO-E’s 2020 report highlights the importance of achieving Europe’s environmental goals:

“To achieve zero emissions, the electricity transmission network will be at the centre Europe has engaged on an ambitious path towards decarbonisation. The major change is the rapid replacement of fossil-fuel generation by renewable energy sources. Electrification is the most direct, effective and efficient way of reaching the decarbonisation objectives. This makes the electricity transmission network the backbone of the future energy system.

Europe will only reach its decarbonisation objective and the successful deployment of variable renewables if:

  • the costs of transforming the system are kept as low as possible, by an appropriate set of investments enabling better market integration and leading to competitive power prices, and
  • the continuous secure access to electricity is guaranteed to all Europeans. Achieving this requires a coordinated, pan-European approach to electricity system planning: the Ten-Year Network Development Plan.”

MaresConnect is in the 2022 list of TYNDP projects and is included in the draft TYNDP 2024 list, which is expected to be finalised in 2025.