Alstom received formal notice to proceed (NTP), which represents final contractual authorization to go ahead on engineering and manufacturing.

Located about three miles off the coast of Block Island, the wind farm will generate about 125,000 megawatt hours of energy per year.

The wind farm, which is expected to start commercial operation in the fourth quarter of 2016, will provide about 90% of Block Island’s energy requirements.

Power will be exported to the electric grid through the 21-mile, bi-directional Block Island Transmission System, a submarine cable proposed to make landfall in Narragansett, Rhode Island.

Alstom senior vice president of wind Yves Rannou said: "This is a major milestone and the confirmation that this project, the first commercial offshore project in the United States for Alstom, will now materialize."

Apart from supplying, installing and commissioning the five turbines for the project Alstom will deliver 15 years of operations and maintenance support.

Deepwater Wind Block Island, a subsidiary of Deepwater Wind, has recently reached financial close on the project.

Gulf Island Fabrication started fabrication work in January 2015 at its facilities in Houma, Louisiana, on the wind farm’s five steel jacket foundations.

Specialty Diving Services expects to start further fabrication work shortly on components of the foundation substructures at Quonset, Rhode Island.

Image: The Block Island offshore wind farm will feature five of Alstom’s 6MW Haliade 150 turbines. Photo: Courtesy of Alstom.