Comprehensive Evaluation of Some Innovative Wind Turbines

A rapid development in wind turbine technology took place during the Second World War and oil crisis of 1973. It continued during twentieths century, which resulted in turbines with bigger size and more advanced technology. Today, large wind turbines are becoming more competitive in the field of electricity generation because of economical production of electricity and availability at rural and remote locations. They have occupied remarkable share in world renewable power generation among various renewable energy sources. On the other hand small wind turbines are not accepted well because of lack of assured performance, cost, efficiency, etc. Therefore some researchers are trying to develop new wind turbine systems to convert wind energy in to electricity. Innovations in the design wind turbine to make them compatible for household use and also to favor their installations by building more eye-catching, efficient and economical wind turbine. To increase acceptability of wind turbines, wind turbine should satisfy the most of the criteria listed in the present study such as, ability to catch the wind from all the direction, self starting, light weight, inexpensive, maintenance free, low weight tower-top system and hence supporting structure, light weight and efficient generator, efficient wind to mechanical energy conversion and manufacturing simplicity at affordable cost and reliable performance. Present study focused on the innovative wind turbines that installed as an offshore and onshore technology. There are more than one hundred of different innovative wind turbine designs listed research papers, books, magazines and internet. In present paper, innovative design aspects of some of these turbines discussed with the technological challenges. Innovations are in the area of blade profile design, aerodynamic shape of the wind turbine, reduction of noise and vibrations, the material of the blade, mechanical and electronic instruments such as gearbox and electronic power circuit, suitability to the application, etc. The aims of these innovations are improvement in the efficiency of the wind turbine; increase in power output and to lower the overall cost. At the end of paper the technological challenges that these innovations overcome, innovative concept and feasibility of the concept are discussed. These innovations include spiral wind turbine, VAWT with accelerator, Windpax-Collapsible portable wind turbine, multi-rotor wind turbines, diffuser augmented wind turbines and floating wind turbines.