Analyses of energy, exergy and aerodynamic characteristics of horizontal axis wind turbines with economic evaluation

In this study, energy, exergy and economic analyses of three-bladed four wind turbines having rated power of 3 MW, and also analyses of energy and aerodynamic characteristics of three-bladed five wind turbines having rated power of 2 MW of two different wind turbine power plants located in Eastern Mediterranean region of Turkey were performed. The measured data such as hourly wind speeds, power values, wind direction and temperatures were arranged. Inlet and outlet wind velocities of wind turbines were found with the aid of the streamwise velocity at the rotor disc and the axial flow induction factor which were calculated using the extracted power, the alternator efficiency, the mechanical efficiency, air density, rotor radius and the streamwise velocity at the rotor disc. The power coefficient, thrust force and The thrust coefficient were determined. Flow induction factor for all turbines increases rapidly after 5 m/s and decreases rapidly after 10 m/s. When the streamwise wind velocity is nearly 6 m/s, all wind turbines behave similarly and they have maximum exergy efficiencies. The horizontal axis wind turbine having the maximum capacity of 2 MW produces an average output power of 672.68 kW for a year under the yearly average free-stream wind speed of 8.49 m/s, with a turbine power coefficient of 30% and a blade tip speed ratio of 6.57. Lastly, the economic analysis of those wind turbines was performed to define specific cost of electricity generation.