## 2 Materials and Methods
### Determination of Wind Energy  
Wind energy systems are naturally energized by the flowing wind, so they can be considered a clean energy source. Wind energy is one of the lowest priced renewable energy technologies available today. However, the biggest challenge of using wind as a power source is that the wind is intermittent and does not always blow when electricity is needed. Wind energy cannot be stored, and not all winds can be utilized to meet the timing of electricity demands. The option of storing energy in battery banks is beyond economically feasible limits for large wind turbines. Although wind power plants have relatively little impact on the environment compared to other conventional power plants, there are some concerns about the noise generated by rotor blades and their esthetic (visual) impacts. Most of these issues have been resolved or greatly reduced by technological development or the appropriate siting of wind farms [28]. Wind turbines can be broadly classified as vertical-axis machines and horizontal-axis machines, depending on the direction of the rotor shaft relative to the approaching wind [29]. In a vertical-axis machine, the rotor shaft carrying the blades is oriented perpendicular to the ground. This allows the turbine to rotate regardless of changing wind direction, eliminating the need for a tail blade or yaw motor and the associated complexities. Furthermore, the gearbox, generator, and associated controls can be located close to the ground surface, allowing easy access for repair and maintenance work. Vertical axis machines are commonly installed in urban environments where wind speed is relatively low and turbulent [29]. The rotation axis of the horizontal axis wind turbines (HAWT) used in this study is parallel to the wind direction. The blades are perpendicular to the wind direction (Figure 1). In these turbines, the condition for faster rotor rotation is to reduce the number of blades. The efficiency of HAWT turbines ranges from approximately 10 to 45%. These turbines should generally be 20 to 30 m above the ground [30]. A wind turbine is the most important part of a wind energy system. It converts the kinetic energy associated with the wind (wind energy) into mechanical energy and then into electrical energy (Figure 2) [32]. Basically, the power equation obtained by a turbine with rotor area \(\rm{A_{r}}\) with density \(\rm{p_{w}}\) and speed \(\rm{v_{\infty}}\) is given below:  
\[\rm{P_{w}}=1/2\times\rm{p_{w}}\times\rm{A_{r}}\times\rm{v_{\infty}}^{3}, \tag{1}\]  
Power is proportional to wind speed and rotor area. However, the size of the rotor, production costs, and site restrictions are all limits for large-scale wind turbines. However, areas with high wind speeds can be effectively utilized to boost the capacity of wind farms to capture energy. The theoretical power that might be produced from the wind is determined by the expression in Equation (1). Different rotor layouts in wind turbines result in different power coefficients. The Betz limit is the power coefficient's highest value, which is 0.5926 [34]. The change in volume (V) with respect to length (l) and time (t), when considering area (A) and applying a wind speed (v), is as follows:  
\[\rm{\Delta V}=\rm{A}\times\rm{\Delta l}, \tag{2}\]  
Figure 1: Structure of a horizontal-axis wind turbine [31]. Figure 2: The conversion of wind energy into electrical energy [33]. \[\
u=\Delta\mathrm{I}/\Delta\mathrm{t}, \tag{3}\]  
which give,  
\[\Delta\mathrm{V}=\mathrm{A}\times\Delta\mathrm{t}\times\mathrm{v}. \tag{4}\]  
Kinetic energy (E) is the form that the wind's energy takes. The following Equation (5) characterized the kinetic energy:  
\[\mathrm{E}=1/2\times\mathrm{m}\times\mathrm{v}^{2}, \tag{5}\]  
where m denotes the wind mass. The relation between the change in mass and the change in energy is linear is defined as follows; i.e.,  
\[\mathrm{m}=\mathrm{V}\times\mathrm{p}_{\mathrm{a}}, \tag{6}\]  
where \(\mathrm{p}_{\mathrm{a}}\) is the specific density of air.