The first offshore wind farm in the US has begun generating electricity about 3 miles (4.8 km) off the coast of Block Island, Rhode Island. The facility has a capacity of 30 MW and is expected to produce around 125,000 MWh of electricity annually.

Project developer Deepwater Wind says that the Block Island Wind Farm will generate enough electricity to power 5,000 homes on the island and to meet around 90 percent of its total electricity demand. It also expects around 40,000 tons (36,300 tonnes) of CO2 to be saved each year as a result of replacing fossil fuel power generation.

Electricity is relayed into the New England grid via a submarine transmission cable system that links the wind farm to the land. The wind farm comprises five 6-MW Haliade turbines supplied by General Electric (GE) Renewable Energy. GE says they are some of the largest turbines in the world, with a diameter of 150 m (490 ft) and a height of 170 m (560 ft).

Construction of the Block Island Wind Farm began in the middle of last year and has involved over 300 local workers. GE Renewable Energy finished the process with a four-month testing period, before announcing yesterday that the wind farm had gone live.