By Josie Le Blond

Led by the University of Maine, the department said the project was the first concrete-composite floating platform wind turbine to be deployed in the world.

With the support of a US$12mn Energy Department investment over five years, University of Maine and its project partners conducted design, engineering, and testing of floating offshore wind turbines, followed by the construction and deployment of its 65-foot-tall VolturnUS prototype.

At 1:8th the scale of a commercial installation, the department said the project would collect data to validate and improve floating wind turbine designs, while helping to address technical barriers to greater offshore wind cost reductions.

According to The University of Maine, its floating wind turbine design features a semi-submersible platform that uses a lower cost concrete foundation in addition to a lighter weight composite tower.

"The Castine offshore wind project represents a critical investment to ensure America leads in this fast-growing global industry, helping to bring tremendous untapped energy resources to market and create new jobs across the country," said Jose Zayas, director of the Energy Department's Wind and Water Power Technologies Office.

Offshore wind represents a large, untapped energy resource for the United States, offering over 4,000 gigawatts of clean, domestic energy potential—four times the nation's current total generation capacity, said the Energy Department.

A recent report commissioned by the Energy Department said a US offshore wind industry that takes advantage of this abundant domestic resource could support up to 200,000 manufacturing, construction, operation, and supply chain jobs across the country and drive over $70 billion in annual investments by 2030.

In Maine, as with many other areas off US coasts, the bulk of this clean, renewable energy resource lies in deeper waters where conventional turbine technology is not practical. Innovations such as floating offshore wind turbines, like the Castine project, will open up new economic and energy opportunities for the country, said the department.