Wind power variability of selected sites in Kenya and the impact to system operating reserve

Results showed that power variations depended on distinctive wind regimes and the number of turbines. Ngong (25 MW) power was evenly distributed between 0 and 100%; Kinangop (60 MW) was concentrated between 20 and 60% and Turkana (300 MW) between 20 and 80% of their respective peak values. The standard deviations reduced as farm capacity increased due to the turbine smoothing effect. The reserve requirements increased on average, 30 MW per percentage wind integration. The combined Ngong/Turkana (325 MW) reserve requirements were less than for Ngong/Kinangop (85 MW), indicating the significance of site correlations. . Also, when Ngong was up-scaled to the same output level as the three interconnected sites (385 MW) reserve requirement increases by 25.5%, thus indicating the importance of geographical spread.