CORRELATION OF WIND PATTERNS USING WEIBULL AND RAYLEIGH MODELS FOR ST.XAVIER SECONDARY SCHOOL, NAIVASHA AND JKUAT SITES

Abstract

The rapidly increasing population and industrialization has led to high energy demand. Juja, having a rapidly growing population and a major University requires an alternative energy source due to frequent power failure. This paper analyzed the wind speed characteristics for purposes of determining wind energy potential in Juja and Naivasha using the heights of 10 m and 30 m and for a period of three months. The wind data was recorded in 10 minutes intervals. Mean diurnal and monthly variations were calculated. The wind speed averages for 10 m and 30 m were 2.54 m/s and 3.04 m/s, respectively. The average wind speeds at the two heights were used to calculate wind shear exponent and roughness parameter for Juja site which were 0.1652 and 0.0374 respectively. Weibull scale and shape parameters were obtained using Weibull-fit, Regression and Maximum LikeliHood. The wind speed distribution was modeled using the Weibull and Rayleigh probability distribution functions. Power densities for different methods were calculated. Results obtained from Juja site were compared with results acquired from Naivasha. The mean power densities for Juja and Naivasha by Weibull model were 12.96 W/m² and 36.52 W/m² respectively. Results by Rayleigh model were 2.82 W/m² and 3.31 W/m². The Weibull-fit and Maximum Likelihood fitted best Juja site and Naivasha respectively. Windographer and Microsoft Excel were used to determine and generate the functions while WindRose diagrams were used to analyze wind direction. The results will guide the designers on selection of appropriate type of wind turbines for optimum power production.