The US Bureau of Ocean Energy Management, Regulation and Enforcement has approved a construction and operations plan for the 468MW Cape Wind project off the coast of Massachusetts.

This is the final approval required to begin construction on the power project developed by US based Cape Wind Associates later this year in Nantucket Sound.

US department of interior secretary Ken Salazar said that the government has taken extraordinary steps to evaluate the power project’s potential impacts on environmental and cultural resources of Nantucket Sound.

"After a thorough review of environmental impacts, we are confident that this offshore commercial wind project – the first in the nation – can move forward," Salazar said.

Siemens will supply 130 turbines for the wind farm,each with a maximum blade height of 440ft.

Electric utility National Grid last year agreed to buy half of the electricity produced by the project under a 15-year power purchase agreement, but the remaining electricity has yet to be sold.