Alliant Energy shut down some of its turbines in Bent Tree Wind Farm after a report that ice from a turbine struck a semi Thursday on Minnesota Highway 13.

The turbines were described by Alliant Energy Spokesman Justin Foss as “select turbines” near Highway 13. The turbines are expected to be inspected this morning as an investigation takes place.

Foss, who said such incidents are not common, noted part of the reason why the turbines were temporarily shut down was to give Freeborn County residents who are sensitive to wind an extra sense that they are investigating.

Goodhue County resident Marie McNamara said she and a friend were heading home from an  evidentiary hearing for the Freeborn Wind Farm Thursday when they received a call from a passerby in the area that ice had struck a vehicle.

McNamara said turbines encounter more problems the older they get, so sufficient distances between turbines and highways and homes are needed. She called Minnesota setback standards “insufficient.”