The Michigan Tax Commission has adopted a new set of equations for determining the taxable value of property which has changed the depreciation schedules for in-service wind turbines. As industrial personal property, wind turbines were previously taxed on 100% of their taxable value in the first year, and depreciated over 15 years down to 30%. In December, the policy was changed to taxing 80% in the first year and depreciating down to 30% over five years.