This executive summary describes a study of wind energy conversion systems for electric utility applications. Complete details are presented in Design Study of Wind Turbines, 50 kW to 3000 kW, for Electric Utility Applications, NASA Report CR-134937, Kaman Aerospace Corporation Report R-1382, hereafter referred to as the ''Design Study.'' The nine-month program was conducted under contract NAS3-19404, awarded by the National Aeronautics and Space Administration (NASA), Lewis Research Center, in November 1974, as a part of the Energy Research and Development Administration's Federal Wind Energy Program. John Sholes was the NASA project manager and provided valuable review and guidance throughout the program.