Assessment of wind characteristics and available wind power at Kilimanjaro international airport (KIA), Tanzania

Knowledge of wind regime is a pre-requisite for any wind energy planning and implementation project. The main purpose of this study is to analyze the available wind data of Kilimanjaro International Airport obtained from Tanzania Meteorological Agent (TMA) which could help planners, potential investors and researchers in identifying potential area for wind energy applications. At 10 m, the annual average wind speed varies from 5.12 m/s to 6.24 m/s. In addition, the maximum and minimum monthly average wind speeds are about 10 m/s and 2 m/s, respectively. The overall average value of the wind speed at the site for the whole period is about 5.50 m/s. Moreover, the monthly average wind speed varies with time exhibiting a cyclic character. The annual mean wind power and energy densities at 10 m varies from 82.11 W/m2 to 144.63 W/m2 and 84.95 kWh/m2 to 157.25 kWh/m2, respectively. The results also indicate that the average shape and scale parameters for the site are respectively 2.27 and 6.42 m/s. Further, the results show that the predominant wind direction is East direction with a frequency of 23.92 % and the most prevailing wind direction is between ENE and ESE which correspond to a frequency of 50.53 %. Also the results reveal that the characteristics wind speed namely cut-in, rated and cut-out wind speeds of the wind turbines at the site are respectively 2.5 m/s, 9 m/s and 18 m/s for 10 m height. In addition, the overall annual average values of optimal and most probable wind speeds were found to be 8.49 m/s and 4.97 m/s, respectively. Finally, the results indicate that the operating probability and operating hours of the wind turbines that fit the wind climate of the sites at 10 m are respectively 88.9 % and 7788.22 hours per year. From the results it can be concluded that the wind energy potential at this site is quite promising for electric generation. It is recommended that further research be conducted at the study site to investigate the wind speed variation in intervals shorter than the three hourly values reported in this study.