A partnership between Ireland’s state-owned utility ESB and Danish energy company Ørsted has won the 900-megawatt Tonn Nua offshore wind auction with a bid of €98.72 per megawatt-hour, Ireland’s Department of the Environment, Climate and Communications (DECC) said on Wednesday.
The project, located off the coast of County Waterford, secured a 20-year Contract for Difference (CfD) after what the department described as a “hugely competitive” second offshore renewable energy support scheme (ORESS) round. The strike price came in below Ireland’s forecast average wholesale electricity cost for 2025 of €114/MWh, the department said.
The ESB-Ørsted alliance outbid several competing consortia, including partnerships between EDF and Bord Gáis Energy, and between RWE and Copenhagen Infrastructure Partners.
The Tonn Nua project is expected to connect to the grid by 2033. Ørsted said it anticipates taking a final investment decision in about 2031, with first power expected in the mid-2030s.
Alana Kühne, Ørsted’s head of Europe development, said the auction result reflects continued momentum in Ireland’s offshore wind sector. “We commend the Irish government for running a successful auction continuing the support for the development of offshore wind in Ireland,” she said. “Offshore wind will play an important part in the future Irish energy system ensuring green, affordable and secure energy.”
ESB’s executive director for generation and trading, Jim Dollard, said the outcome provides clarity for the development of a major project. “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,” he said, adding that the project would offer “energy security and price certainty for Irish consumers.”
Energy Minister Darragh O’Brien said the result marks “an important milestone” in Ireland’s offshore renewable strategy. “The highly competitive price secured represents positive news for Irish energy consumers and our nation,” he said. O’Brien added that the outcome signals strong international confidence in Ireland’s offshore potential, noting that the sector “has the potential to deliver tens of thousands of new green jobs.”
The auction result remains provisional until final confirmation on 9 December. Tonn Nua is one of four designated maritime areas in the South Coast Designated Maritime Area Plan (SC-DMAP) zone. The government said it will now prepare to bring the remaining three sites to market.
