The ground-mounted array will be built across 100 acres (40 hectares) of “underutilized” land at Camp Ripley, a central Minnesota training facility currently used by the state’s National Guard.

The $25m project is due for completion by 2016.

Last year Mark Dayton, Minnesota’s Democratic governor, signed into law a requirement that the state’s investor-owned utilities source at least 1.5% of their electricity from solar by 2020 – a modest target that was nevertheless opposed by most of the state’s utilities.

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