Wind turbine

The move marks the completion of the fourth phase of the project, which features 165 turbines.

The fourth phase, Bison 4, features 64 Siemens turbines and output is delivered to the utility’s customers through a 465-mile direct current transmission line connecting with Duluth.

Construction of the $345m Bison 4 started in the fall of 2013. It included around 14 miles of new roads and upgrades to about 11 miles of existing roads.

About 55 miles of collector cable were installed and a new electric substation was constructed to serve the western side of Bison 4.

Plans also included the expansion of an existing substation, a new meteorological tower and 11 miles of new 230-kilovolt transmission line.

Allete chairman, president and CEO Al Hodnik said: "Development of renewable energy from wind and water is rapidly transforming our nation’s energy landscape and with the addition of nearly 500 megawatts of wind from the Bison development on our system, we are providing cleaner energy while maintaining the affordability and reliability of electric power our customers in northeastern Minnesota expect."

Minnesota Power chief operating officer Brad Oachs said: "With this substantial addition of wind to our portfolio, we are meeting Minnesota’s renewable standard of 25 percent renewable energy by 2025, a decade early."

Image: The 205MW fourth phase expansion of the Bison wind energy center increases the facility’s total capacity to about 500MW. Photo: Courtesy of pakorn/