Wind energy resource assessment for Suva, Fiji, with accurate Weibull parameters

Abstract

Wind resource assessment is carried out for Suva, the capital of the Republic of Fiji Islands. The wind speeds at 34 m and 20 m above ground level, wind direction, atmospheric pressure, and temperature were measured for more than five years and were statistically analyzed. The daily, monthly, yearly, and seasonal averages were estimated. For the site, the overall average wind speed at 34 m above ground level is found to be 5.18 m/s. The occurrence of effective wind (between the cut-in and cut-off wind speeds of the selected turbine) is predominantly from the east. An effective wind speed of 74.175% was recorded which can be used for power generation. The turbulence intensity and wind shear coefficient are estimated. The site’s overall turbulence intensities are 12.5% and 13.72% at 34 m and 20 m above ground level, respectively. The diurnal wind shear correlated with the temperature variation very well. The overall and seasonal wind distributions are analyzed, which shows that the wind speed in Suva is mostly between 3 m/s and 9 m/s although the winter season has higher wind speeds. The Weibull parameters and the wind power density were found using 10 different methods. The wind power density is estimated to be 159 W/m2 using the best method, which is found to be the empirical method of Justus. A high-resolution map around the site is digitized and the wind power density resource map is generated using wind atlas analysis and application program. From the wind atlas analysis and application program analysis, it is seen that Suva has high potential for power generation. Five possible locations are selected for installing wind turbines and the annual energy production is estimated using wind atlas analysis and application program. The total annual energy production from the five sites is 1950 MWh. The average capacity factor of the five turbines is 17%. An economic analysis is performed which showed a payback period of 10.83 years.