**there is a losses in the process of converting wind energy to electrical energy , the losses are due to the friction in the turbine-generator ,and frictional losses in the gear box , and losses due to the air flow , turbulence and drag.**

**bitz-limit is a theory introduce by a German scientist , that says the maximum power that extracted from the wind turbine will not be greater than 59% of the wind power , since the wind turbine can only convert 2/3 of the wind speed to kinetic energy.**

**the total output power of the wind turbine(W)=.5*rho*V^3*efficiency*CP*swept area**

**where rho=the air density about 1.3 (kg/m^3), the efficiency of the wind turbine , CP :bitz-limit coefficient about .59, swept area is the area captured by the rotating blades (m^2), V:is the wind speed m/s.**

**example assumes we have a wind turbine with blade radius =100 m , efficiency =80% ,and mean wind speed 10m/s what is the output power of the wind turbine,assume air density 1.3 kg/m^3?**

**the total output power of the wind turbine(W)=.5*rho*V^3*efficiency*CP*swept area**

** =.5*1.3*10^3*0.8*.59*(pi*(100/2)^2)**

** =2388438 watt**