Mathew Gard, ERS, for Zondits
Off the coast of Block Island, 10 miles south of Rhode Island in the Atlantic Ocean, five gigantic wind turbines mark the beginning of offshore wind power in the U.S. The five turbines that will make up the Block Island wind farm are each capable of producing 6 megawatts (MW) of power. The farm will have the have the capacity to meet almost all of Block Island’s energy needs and, via an undersea cable, will be able to deliver surplus power to the mainland. Built by GE, the turbines use a gearless generator, which increases reliability and reduces maintenance compared to conventional gear-driven turbines.
A wind farm with five turbines certainly doesn’t sound impressive until you see the sheer size of the turbines and the herculean effort it took to manufacture, deliver, and assemble them at sea. Each 400-ton nacelle sits atop a 330-foot tower. The blades (there are three on each turbine) are 240 feet long and weigh 27 tons. At one point, the installation crew even had to hoist the ship that delivered the components out of the water. The pictures in the link below do a good job of illustrating the monumental task of erecting a farm of 6 MW wind turbines at sea.