Offshore Wind and Interconnected Grids: CEOs of the Offshore TSO Collaboration unite for Europe’s energy future

During today’s press conference at the WindEurope Annual Event 2025, the Offshore TSO Collaboration (OTC) presented the initial results of a pilot study it undertook which is aimed at developing a joint European offshore grid for the Irish, Celtic and North seas. 

This analysis supports Europe’s goal of establishing a ‘green power plant’ offshore that will play a crucial role in the continent securing an independent, affordable and climate-neutral energy supply for itself.

Joint grid development

Over the past three years, transmission system operators (TSOs) have collaborated as part of the North Seas Energy Cooperation grouping to advance infrastructure development in line with the objectives of the Esbjerg and Ostend Declarations. 

Both declarations aim to significantly increase the combined offshore wind capacity of the North Sea. The initial results of their joint study demonstrate how a regional approach to offshore grid development in this region can offer both economic and environmental benefits.

The analysis includes a grid map that outlines promising cross-border projects. These projects are not considered in isolation; instead, they are considered as part of a broader offshore regional grid, maximising synergies and cost efficiencies. 

This represents an important step towards a more affordable, secure and reliable offshore system that strengthens Europe’s energy supply and independence while supporting its decarbonisation goals.

A formalised joint planning process

The OTC intends to submit a set of these conceptual projects to the Ten-Year Network Development Plan 2026, which recognises the most critical strategic electricity transmission projects across the EU.

Furthermore, the OTC is proposing a continuous regional planning process that would complement existing plans such as the Ten-Year Network Development Plan and embedded Offshore Network Development Plan (ONDP),  enhancing coordination and efficiency.

The development of a robust offshore infrastructure is critical for Europe’s energy future. With continued political support and increased collaboration, Europe can advance its ambitious plans for a robust interconnected energy system and position itself as a leader in offshore renewable energy.

The results and next steps were presented at the press conference that was held by executives of the OTC TSOs, including EirGrid Chief Infrastructure Officer Michael Mahon.

Commenting on the opportunity presented by the new analysis, Mr Mahon said: “Today marks a significant moment for future offshore renewable energy development in this region, and Ireland has a key role to play in this.

“Our work as part of the OTC can contribute significantly to regional planning, supporting the achievement of our collective offshore wind objectives. 

"A logical next step is to consider how the grid map and the recurrent planning process we are proposing can be used as the basis for discussions on how cost sharing can work for offshore energy infrastructure in the region.

“Following on from today’s important developments, the OTC will continue work on other critical topics for the development of offshore wind including infrastructure security, noting its increasing importance in the current geopolitical climate, as well as the development of ideas and concepts relating to markets and technical issues.”

Key messages from the CEOs

During the press conference, the CEOs of the OTC, who represent leading European TSOs, underscored the importance of a unified and efficient offshore grid development strategy for the Irish, Celtic and North seas that is aimed at maximising benefits for Europe’s energy security, independence and competitiveness.

To achieve these objectives, the CEOs emphasised that energy independence must begin at sea, with offshore wind farms and the grids that connect them to the shore. 

This region holds immense potential with regard to providing Europe with reliable, clean and affordable energy. However, unlocking this potential will require coordinated European action and the development of the necessary offshore and onshore infrastructure to transport offshore wind power from generation sites to onshore consumption centres.

The CEOs stressed that national solutions alone will not suffice, as renewable energy resources are unevenly distributed across Europe. Large-scale interconnectors are essential for strengthening the European electricity system and ensuring that energy flows efficiently across national borders.

Looking ahead, the CEOs recognised the significant economic opportunity offshore wind presents for Europe.

They cited a recent study by Elia Group, which demonstrated that if international collaboration is fully harnessed, risks reduced, and effective offshore spatial planning implemented, Europe could save over €1000 billion in energy system costs from 2030 to 2050. 

They also called for the rapid scaling up of the offshore wind supply chain, with dedicated hubs across the EU to manufacture turbines, cables, platforms, and other components, with the potential to create up to 300,000 jobs.

The CEOs also pointed out that Europe needs a robust framework that attracts greater investment and reinforces the continent’s position as a technological front-runner in offshore wind. Such a framework will help to scale up the industry and ensure that Europe maintains its leadership in the sector.

While collaboration between TSOs is already enabling the operation of the world’s largest interconnected electricity system, the CEOs stressed the need for political and regulatory alignment. 

They called for a new level of formalised, continuous planning, that could support a government endorsed regional approach, to accelerate offshore development and enhance existing national planning processes with a holistic sea basin perspective.

Their message was clear: the time for action is now, and they are ready to plan, coordinate, and deliver a sustainable and interconnected offshore future for Europe, in close relation with the States, the regulators and the energy producers.

About the OTC

The OTC was established in 2022 and consists of TSOs from the Northern Seas which are working together to develop a sustainable offshore network infrastructure. 

The OTC’s aim is to establish the North Sea as a hub for renewable energy and support Europe’s energy security and decarbonisation objectives. 

These companies work together to drive the development of offshore grids in the North Sea, supporting the political goals set by the Esbjerg Declaration (2022) and the Ostend Declaration (2023). 

The member companies are as follows: 50Hertz (Germany); Amprion (Germany); Creos (Luxembourg); EirGrid Group (Ireland); Elia (Belgium); Energinet (Denmark); National Grid (United Kingdom); RTE (France); Statnett (Norway); TenneT Holding (TenneT Netherlands and TenneT Germany).