Employing power spectral density method for investigating atmospheric stability impacts on power generation of a wind farm

Abstract

ABSTRACT Theoretically, the output power of a wind farm is mainly under influence of wind speed as an atmospheric parameter. However, there are other factors that impact wind power generation. Atmospheric stability is one these features. The main contribution of this study is to investigate the impact of atmospheric stability on efficiency of Manjil wind farm in Iran for summer of 2004. For accomplishing the task, wind speed distributions and power generation amounts of the farm for three different months of the summer were investigated. The investigation showed that in the first and second month wind speed values for 82.3 and 87% of the times were more than 8.8 m/s, respectively. However, power generation in the first month was 4.96% more than the second one. Considering the impact of atmospheric stability on power production, the stability was inspected by employing wind shear exponent as a common metric and Power Spectral Density method as a rather new approach. The results showed that in the first month the atmosphere was instable for 91% of the times. This percent for the second month was 82%. The results support the idea that atmospheric instability has positive impact on efficiency of the wind farm.