Ireland has announced the provisional results of its second offshore wind auction under the Offshore Renewable Electricity Support Scheme (ORESS), awarding a contract for the 900 MW Tonn Nua project off the coast of Waterford. Darragh O'Brien, Minister for Climate, Energy and the Environment, said the outcome reflects continued international interest in Ireland’s offshore wind sector.

The Tonn Nua auction resulted in a strike price of €98.719/MWh for a 20-year support contract. The price is below Ireland’s average wholesale electricity price so far in 2025, estimated at €114/MWh, and compares with offshore wind auction results in other European markets over recent years.

The winning bidder is Helvick Head Offshore Wind DAC, a joint venture between Ireland’s utility ESB and Danish renewable energy company Ørsted. The partnership was established in 2023 to develop offshore wind projects off the Irish coast.

Tonn Nua is the first project to be auctioned under Ireland’s South Coast Designated Maritime Area Plan (SC-DMAP) and is located offshore from Waterford. Once operational, the project is expected to generate enough electricity to supply close to one million homes and to avoid an estimated 1.8 million tonnes of CO? emissions annually.

According to the Department of Climate, Energy and the Environment, the project will also include a Community Benefit Fund. The fund is set to provide approximately €140 million over 20 years to communities near the development, starting prior to construction. Annual contributions of around €7 million will be allocated to local environmental, social, economic and cultural initiatives.

Commenting on the results, Darragh O'Brien, Minister for Climate, Energy and the Environment, said: "The provisional results of the Tonn Nua auction mark an important milestone in the State's offshore renewable energy ambitions. The highly competitive price secured represents positive news for Irish energy consumers and our nation, bringing us closer to overcoming the challenges of energy security and affordability, and towards achieving energy independence. It's also a positive reflection of Ireland that we, as a country, can develop and produce enormous quantities of clean energy. It's a clear sign that international companies are confident in Ireland's ambition and infrastructure."

Noel Cunniffe said the price compares with recent European offshore wind auction results and highlighted the scale of electricity generation expected from the project.

However, Wind Energy Ireland also pointed to a lack of clarity around the timeline for future offshore wind developments. While three additional south coast sites have been identified, the organisation noted that details on sequencing and auction schedules are not yet defined. It added that progress on Tonn Nua and five existing offshore wind projects on the east coast will be important while the Government works towards publishing a national offshore development map, currently planned for 2027.

The Tonn Nua auction results are provisional and subject to standard confirmation procedures, with final results due to be announced on 9 December.

Industry reaction

Wind Energy Ireland welcomed the provisional outcome of the auction for the 900 MW Tonn Nua offshore wind project off the coast of Waterford, describing the result as a positive signal for offshore wind investment in Ireland. The project was awarded at a strike price of €98.72/MWh to a joint venture between ESB and Ørsted, a price the industry body said compares with recent offshore wind auction results elsewhere in Europe, where some rounds have failed to secure bidders.

Noel Cunniffe, CEO of Wind Energy Ireland, said that the auction "is a great vote of confidence in Ireland as a place to invest for offshore wind energy. Tonn Nua will deliver enormous volumes of clean, affordable, electricity for Irish consumers and represents a huge economic opportunity for Waterford and the south-east of Ireland generally. [...] The department deserves credit for a very well-designed auction system which has delivered for Irish consumers at a strong price."

However, the association also pointed to ongoing uncertainty around the future project pipeline. Cunniffe said that while additional offshore wind sites have been identified along Ireland’s south coast, there is currently no clarity on their timelines or routes to market. He added that closer coordination between industry and State agencies will be needed to progress Tonn Nua and the existing offshore wind projects on the east coast while the Government works towards publishing a national offshore development map, currently planned for 2027.