Many countries worldwide support green energy production on large scale mostly by solar or wind energy subsidizing manufacture and operation of such systems. During the last two decades, there has been significant increase in wind energy production globally. Statistics show continuously growing investments in the development and installation of wind turbines and farms. Currently, wind energy is the second most important source of renewable energy after water energy. By 2016 global cumulative installed wind capacity surpassed 432 k MW [GWEC]. In last several years, most dynamic growth in wind power generation investments was recorded in Asia. Europe, in comparison, has less impressive but steady growth in wind power plants through the years. In this article, authors present global demand on energy in comparison to efficiency of wind power plants in relation to the local and global location as well as to the scale of installed system. Authors also present statistical data concerning wind power plants development. General classification, using number of criteria (ex. power output, construction size, rotor axis orientation and other) of wind to electric power converting devices is presented. Various types of devices, which authors describe in this article, can perform conversion of wind blow energy to the electric energy using different yet similar methods.