Golden Valley-based Mortenson has been selected by Xcel Energy to build a new $740 million wind farm in Colorado, one of Mortenson's largest renewable energy projects to date.

Mortensen will build the Cheyenne Ridge Wind Project, a 500-megawatt capacity wind farm on about 100,000 acres in eastern Colorado. Mortenson, a multi-purpose builder whose projects include U.S. Bank Stadium, is one of the nation's largest wind energy construction firms.

Mortenson also built Xcel's 600-megawatt Rush Creek wind farm in Colorado, which is both Minneapolis-based Xcel's and Mortenson's largest completed wind project. Rush Creek went online late last year.

In Minnesota, privately-held Mortenson has constructed several wind farms and is currently working on Xcel's Blazing Star I, a 200-megawatt project near Hendricks in southwestern Minnesota. Colorado and Minnesota are Xcel's two largest service areas and both states are national leaders in wind power production.

A megawatt is one million watts, and 500 megawatts of generation capacity ­-- Cheyenne Ridge's size -- is on par with the size of a coal or large gas-fired power plant, except that wind farms can only produce power intermittently.

The Cheyenne Ridge wind farm is expected to be completed by December 2020. Turbines for the project will be supplied by Vestas, a major wind power equipment maker based in Denmark.