Minnesota utility regulators approved Xcel Energy’s plan to add four wind farms that will boost its wind power capacity in the Upper Midwest by 42 percent. The firm also operates major wind farms in the Rockies. (Evan Ramstad — Bloomberg News/The Minnesota Star Tribune)

Minnesota utility regulators on Thursday approved Xcel Energy's plan to add four Upper Midwest wind farms that will boost its wind power capacity in the region by 42 percent.

The decision by the state Public Utilities Commission (PUC) clears the way for Minneapolis-based Xcel and two energy development companies, including Geronimo Energy of Edina, to push ahead with the goal of meeting deadlines to secure lucrative federal tax credits.

Regulators rejected a request by other wind energy interests to extend the review process on the four projects in Minnesota and North Dakota.

Xcel didn't disclose the cost of the projects, including two that it will own and its customers will pay for in their rates. But the company said the projects are such a good deal that ratepayers will save $225 million over the projects' lives.

"Wind energy is a clean, low-cost substitute for natural gas and other fuels right now," Dave Sparby, Xcel's regional CEO, said in a statement.

Xcel said the wind farms will generate enough power to serve about 200,000 homes and reduce carbon emissions by more than 1.5 million tons a year. The additional 750 megawatts of power is expected to be on line in 2015.

Two of the projects are the Courtenay Wind Farm near Jamestown, N.D., and the Odell Wind Farm near Windom, Minn. Geronimo will develop those wind farms and the power will be sold to Xcel under a long-term contract.

Xcel will own the other two planned wind farms: Pleasant Valley, near Austin, Minn., and the Border Winds Project in Rolette County, N.D. Both are being developed by RES America Developments Inc., which will sell them to Xcel on completion.

Some of the projects require additional regulatory approval, including by North Dakota utility regulators.

All four projects aim to qualify for the federal wind Production Tax Credit, which was temporarily renewed by Congress in January. To qualify for the credit, which amounts to about 30 percent of a project's cost but is paid out over 10 years, project developers must take steps to get started, such as ordering turbines, before the end of this year.

David Shaffer • 612-673-7090 Twitter: @ShafferStrib