For the new wind turbine, the maintenance cost is very low, wind turbine maintenance will increase if the turbine old. The old wind turbine has average maintenance cost in each year about 3 percent of the turbine original cost price. The turbine which is new are quite stronger and have a price in economic site is low. So, the maintenance of wind turbine per kW of rated power has low cost. Most of maintenance cost of a wind turbine will be a fixed amount each year for regular service, but is can be preferable to base the maintenance cost on a per kWh rate. These is purely because of tear and wear increasing on the turbine with increasing production, so there is a balance between savings compared to cost. (Windmeasurementinternational.com, 2015)