Estimation of different wind characteristics parameters and accurate wind resource assessment for Kadavu, Fiji

Abstract

Wind resource assessment is carried out for a site in Kadavu, Fiji Islands. This included estimating the Weibull parameters and wind power density using ten different methods and carrying out an economic analysis. The wind speeds at 34 m and 20 m above ground level, wind direction, atmospheric pressure and temperature were measured for 18 months and statistically analyzed. The overall average wind speed at a height of 34 m above ground level was found to be 3.63 m/s. The seasonal averages for the site were 3.81 m/s and 3.40 m/s for summer and winter respectively. The diurnal variation of the wind shear for the site was correlated with the temperature variation. The Moments Method was found to be the best method for the entire period of study. The Modified Maximum Likelihood Method was found to be the best for the summer season whilst Median and Quartile method was the best for the winter period. The mean wind power density at the location was found to be 45.88 W/m2. The WAsP software was used to create the wind resource map. Five potential sites were selected installing the wind turbines and for carrying out the economic analysis, which included an estimation of annual energy production. It was found that, for the five turbines average capacity factor would be 20.05%. The payback period for installing the wind turbines at 50 m above the ground level is estimated to be between 6.99 and 8.74 years.

Keywords

• wind energy
• weibull parameters
• wind shear coefficient
• turbulence intensity
• annual energy production