Horizontal axis wind turbines are widely used for electricity power generation. The experimental study is done on HAWT to increase the power generation by using the baseline model, extended flat plate model and extended serration model of S809 airfoil blade. All the models were tested using open jet test section wind tunnel at a free stream velocity of 20 m/s. The main focus is to increase the aerodynamic performance of HAWT by testing with different model blades at different angles. The static and stagnation pressure is found using the pressure rake connected with pressure scanner at various locations from 1D (rotor blade diameter 40 cm) to 6D to find downstream velocity and turbulence intensity. The results were found and compared with the different downstream locations. Comparatively the extended flat plate model shows high downstream velocity.