U.S. Department of Energy - Energy Efficiency and Renewable Energy

Wind Program

Maine Project Launches First Grid-Connected Offshore Wind Turbine in the United States

May 31, 2013

The Energy Department today recognized the nation's first grid-connected offshore floating wind turbine prototype off the coast of Castine, Maine. Led by the University of Maine, this project represents the first concrete-composite floating platform wind turbine to be deployed in the world—strengthening American leadership in innovative clean energy technologies that diversify the nation's energy mix with more clean, domestic energy sources.

"Developing America's vast renewable energy resources is an important part of the Energy Department's all-of-the-above strategy to pave the way to a cleaner and more diverse domestic energy portfolio," said Jose Zayas, director of the Energy Department's Wind and Water Power Technologies Office. "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."

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. According to a recent report commissioned by the Energy Department, a U.S. 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 U.S. coasts, the bulk of this clean, renewable energy resource lies in deeper waters where conventional turbine technology is not practical. Innovative floating offshore wind turbines, like the one launched today, will open up new economic and energy opportunities for the country.

With the support of a $12 million Energy Department investment over five years, University of Maine and its project partners conducted extensive 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, this project will collect data to validate and improve floating wind turbine designs, while helping to address technical barriers to greater offshore wind cost reductions.

The University of Maine design uses advanced materials that help reduce the overall cost of the system while ensuring high performance and efficiency. For example, the floating wind turbine features a unique semi-submersible platform that uses a lower cost concrete foundation in addition to a lighter weight composite tower. As part of the five-year project, the Maine Maritime Academy helped test and conduct analysis on these pioneering designs, while the Pittsfield, Maine-based Cianbro Corporation leveraged its experience in maritime energy infrastructure and ship building to construct this first-of-its-kind wind energy system.

As part of a separate project, the University of Maine is planning a larger offshore wind demonstration called Aqua Ventus I—one of seven offshore wind design and engineering projects announced last year by the Energy Department. Upon completion of the engineering and design phase, the Department intends to select up to three projects for additional funding in 2014 to support construction and installation.

Find more information on the Energy Department's broader efforts to grow America's wind energy industry at www.wind.energy.gov.