Five Wind Speed Interpolation Method Analysis

All the twenty nine weather stations are distributed quite evenly in the entire kingdom. A spatial interpolation technique is used to predict the wind speed between the weather stations, where direct measured data is not available. In this analysis, the method used to convert the point data into raster format is the inverse distance weighted, IDW. It determines cell values using a linearly weighted combination of a set of sample points. The weight is a function of inverse distance. The surface being interpolated should be a variable dependent on location. The IDW interpolation technique was applied as it was found to be more accurate. Ali et al. [32] tested five wind speed interpolation methods (i.e. IDW, global polynomial interpolation, local polynomial interpolation, spline with 3 sub-types, and kriging with 4 sub-types) in Iraq. Based on the root mean square error values, the predicted values are compared with actual values for period between 1971 and 2010. The results demonstrated that the IDW yielded the best results, while the ordinary Kriging method occupied
However, many studies recommend a buffer distance as well [12, 16, 17, 18, 19]. This buffer or preventive distance is decided by regional planning authorities. The access roads to wind farm must also have a minimum width of 4 m with a pavement [14]. In most wind farm siting assessments, the areas further away from roads are considered less suitable than those closer to roads [12, 14, 15, 25, 35, 36, 37]. However, there is no generally valid definition of a maximum distance from the wind turbines to the road network. Out of seven studies which considered distance from road criterion, two used a maximum distance of 5000 m [12, 14], one used 10000 m [15] and three others used buffer distance of 100 and 200 m only [16,