Australia-based Babcock and Brown is keeping the operation part of the Gulf Wind project, but has sold the rights to its expansion. Initial plans called for a total of 157 wind turbines and thus far 118 are spinning.

Babcock's North American Energy Group joined Riverstone Holdings to form Pattern Energy, which bought the development rights to Gulf Wind's second phase. Pattern is an independent energy company that develops, constructs, owns, and operates renewable energy and transmission assets across North and South America.

Babcock doesn't discuss ongoing asset sales, officials have said. The company announced the sale of its North American Energy Group to its shareholders in May.

Officials with Riverstone declined to comment, referring questions to Pattern Energy spokeswoman Beth O'Brien.

O'Brien said the operational portion of the wind farm also is for sale and that she could not speculate on its future. She declined to disclose the purchase price of Babcock and Brown's assets.

Pattern's projects exceed 4,000 megawatts and the company has about 1,000 megawatts of development assets and interests in West Texas and the Panhandle. This includes the entire 80-person development team.

Babcock and Brown is traded publicly on the Australian Securities Exchange. Other than announcing the sale last month, information about it, including the sale price and terms, was not available through that organization's or the company's Web.