Abstract
Wind energy considered to be the most recent source of power that inexpensive, non-depleting, also simple for a variety of users to capture and employ. The location of Ali El Gharbi is one of the preferable sites for clean energy production in Iraq, however as there is a lack of information about the power exploration potentials at this place, more related researches and studies for wind power wind are fundamental. An accurate comprehension for the behaviour of the wind is required for the preparation and operation of every wind conversions to energy project. The study is aimed at investigating the novelty in modifying the Weibull distribution by means of the Fast Fourier Transform with the purpose of estimate the possibility of wind energy harvesting in Ali El-Gharbi area of Ammarah, Iraq. The results from the modification of the Weibull distribution was a reduction in the value of the shape parameter for the new Weibull distribution which will lead to a smoother curve, the reduction of the shape parameter from about 5 to 1 implies a shift from the scenario where failures occur randomly and independently of the parameter. A second benefit of the modification was a reduction the time for calculation the Weibull parameters and PDF’s with increasing the accuracy. As an outcome of the wind speed data values were recorded at a 10-minutes interval for a year starting from December 2014 till December 2015 at heights of 10, 30, and 50 meters. Subsequently, the datasets were examined by means of the Weibull probability distribution function (WPD) to assess wind energy production, and for the spectral part of the analysis was conducted by employing the Fast-Fourier-Transform. According to the spectral analysis for the data, the average yearly wind speed at 50 m was 6.134 m/sec, whereas highest wind speed recorded there during the day were about 17.011 , and the peak wind speed was 226236.282 m/sec/12hour at a frequency(2 Hz) at that height of 50 m all through night hours. And for lowest values of wind speed was about 115863.7 m/sec/12hour for the (2 Hz) frequency at that height throughout night hours. The blowing of wind was more rapidly in the morning than it was at night periods. While the main wind directions in the region were from the north-northwest and west-northwest.

Key words: Wind energy, Wind Speed, Spectral distribution, Fourier series, Weibull distribution.