Offshore wind: ESB and Orsted win 2^nd Irish tender for Tonn Nua (900 MW)

Helvick Head Offshore Wind DAC, a 50/50 joint venture between Irish energy company ESB and Danish developer Orsted, has been named provisional winner of the offshore wind tender for a 900 MW wind farm at the Tonn Nua site in Ireland, at a tariff of €98.719/MWh, the Irish Department of Climate, Energy and the Environment announced on 26/11/2025.

The Tonn Nua site, located around 12 km off the coast of Waterford, has been identified under the South Coast Designated Maritime Area Plan (SC-DMAP) as the exclusive site for the country's second offshore wind auction. This State's first spatial plan dedicated to the development of marine renewable energies has identified a total of four sites where a total of 5GW will be developed.

Under the terms of the contract, the successful bidder will pay €140M over 20 years, or around €7M/year, into a fund that will benefit local communities through grants to local clubs, associations and projects.

"The provisional results of the Tonn Nua auction mark an important step forward in Ireland's ambitions for offshore renewable energy. The extremely…