Interior secretary Ken Salazar approved the Cape Wind renewable-energy project on federal submerged lands in Nantucket Sound, which has long been the focus of debate in the state.

“After careful consideration of all the concerns expressed during the lengthy review and consultation process and thorough analyses of the many factors involved, I find that the public benefits weigh in favor of approving the Cape Wind project at the Horseshoe Shoal location,” Salazar said at the Massachusetts State House in Boston. “With this decision, we are beginning a new direction in our nation’s energy future, ushering in America’s first offshore wind-energy facility and opening a new chapter in the history of this region.”

The Cape Wind project would be the first wind farm on the U.S. Outer Continental Shelf. It is estimated it would generate enough power to meet 75 percent of the electricity demand for Cape Cod, Martha’s Vineyard and Nantucket Island. The project would create several hundred construction jobs and be one of the largest greenhouse gas reduction initiatives in the nation, cutting carbon dioxide emissions from conventional power plants by 700,000 tons annually.

Several similar projects have been proposed for other northeast coastal states, positioning the region to tap 1 million megawatts (MW) of offshore Atlantic wind-energy potential.

Because of concerns expressed during the consultations, Salazar has required the developer to change the design and configuration of the wind turbine farm to diminish the visual effects of the project and to conduct additional seabed surveys to ensure that any submerged archaeological resources are protected prior to bottom-disturbing activities. Under these revisions, the number of turbines has been reduced from 170 to 130.
“After almost a decade of exhaustive study and analyses, I believe that this undertaking can be developed responsibly and with consideration to the historic and cultural resources in the project area,” Salazar said. “Impacts to the historic properties can and will be minimized and mitigated, and we will ensure that cultural resources will not be harmed or destroyed during the construction, maintenance, and decommissioning of the project.”

The Cape Wind Associates facility would occupy a 25-square-mile section of Nantucket Sound and generate a maximum electric output of 468 MW with an average anticipated output of 182 MW. At average expected production, Cape Wind could produce enough energy to power more than 200,000 homes in Massachusetts.

According to Cape Wind, one-fifth of the offshore wind-energy potential of the East Coast is located off the New England coast, and Nantucket Sound receives strong, steady Atlantic winds year round. The project includes a 66.5-mile buried submarine transmission cable system, an electric service platform and two 115-kilovolt lines that connect to the mainland power grid.