Xcel Energy, the nation’s leading wind power utility, announced yesterday that it will add three large wind farms to its wind energy portfolio.  The 600 megawatt increase is the utility’s single largest increase in its Upper Midwest service area.

The 33 percent increase will augment Xcel’s existing 1,800 megawatts of wind capacity and allow it to power an additional 180,000 homes via wind.  The utility estimated that the increase in wind capacity will allow customers to save $180 million over the projects’ 20-year life span compared to electricity generated from Xcel’s existing power plants.

A major reason for the savings is the extension of the federal production tax credit.  As long as the three projects begin construction by December 31, 2013, the projects will receive a 2.3 cents/kWh subsidy for the first ten years of operation.

In addition to providing cheaper electricity, Xcel’s planned increase in its wind portfolio will help it achieve its 31.5% mandate under Minnesota’s renewable portfolio standard.  The standard requires that eligible renewable electricity account for 31.5% of Xcel’s total retail electricity sales in Minnesota by 2020.