The annual electrical energy demand for Penn State University Park campus is 300,000,000 KWh. Is it possible to build a wind farm that could provide electricity throughout the year to a University in PA? If so, how many wind mills will be required to build the wind farm. Average wind speed in Pennsylvania is 15 mph. A state-of-the-art windmill has a rotor blade length of 75 m and the practical efficiency of a wind mill is 40%.