Last Updated on November 29, 2025 by Author
The Irish Department of Climate, Energy and the Environment has provisionally awarded the joint venture, formed by ESB and Ørsted, the rights to develop the Tonn Nua site, which is off the coast of County Waterford and spans 306 km2.
Tonn Nua has been designated by the Irish government as the only site for bidders under the Offshore Renewable Electricity Support Scheme (ORESS), Tonn Nua, Ireland’s second offshore wind auction. The auction offers a partially indexed 20-year contract for difference (CfD), and the right to apply for a seabed lease and grid connection for the winning bidder. The contract for difference is to support the development of a 900 MW fixed-bottom offshore wind farm for the Tonn Nua site.
The Tonn Nua site is in an early phase of development. The project now needs to be assessed, matured, and successfully pass all gates in the JV’s stage-gate process, including meeting the value creation criteria. Final investment decision is expected around 2031 and first power in the mid-2030s.
Alana Kühne, Head of Region Europe Development at Ørsted, said: “We commend the Irish government for running a successful auction, continuing the support for the development of offshore wind in Ireland. Offshore wind will play an important part in the future Irish energy system, ensuring green, affordable and secure energy. We will continue to work with our joint venture partner ESB to carefully assess and progress this early-stage development opportunity, including ensuring that the project lives up to our value creation criteria.”
Jim Dollard, Executive Director for Generation & Trading at ESB, commented: “ESB is delighted with the outcome of the ORESS Tonn Nua auction. It secures a clear pathway for the development of a significant project off the coast of County Waterford, marking another important step toward Ireland’s renewable energy and Net Zero ambitions. We look forward to working with our partners to deliver a project that provides significant energy security and price certainty for Irish consumers.”
The awarded project is for a fixed-bottom offshore wind development at the Tonn Nua maritime site, located off the coast of County Waterford.
ORESS Tonn Nua is Ireland’s second support regime for offshore renewable energy development, and the first offshore wind auction under the new state-led planning regime.
The next step for the project is to seek a Maritime Area Consent and Marine Usage Licence from the Irish Maritime Area Regulatory Authority in order to commence surveying and assessment ahead of submitting a planning application for the development.