Potencial eólico na direção predominante do vento no Nordeste do Brasil.

Abstract

Hourly mean data of wind speed and direction, measured with anemograph Fuess at 10 m height, were used in this study. These data were collected in the period from January ?977 to December 1981 at 77 weather stations located in Northeast of Brazil. The main objective of the study was the determination of the wind energy power for the predominant wind direction of each selected station. To do so, the identification of the relative frequency related to the hourly mean wind speed of the predominant direction was performed. Then, the Weibull parameters, related to the hourly mean wind speed of the predominant direction at each station monthly, were estimated according to the Moment and the Graphical methods. The goodness of the fit was evaluated according to the Kolmogorov-Smirnov test. The results show that the wind predominant direction, at Northeast as a whole, was East, with variation to Northeast and Southeast. The highest wind speed values, on average 4.3 m/s, were found in Rio Grande do Norte State, while the lowest wind speed values, on average 2.7 m/s, were observed in Maranhao State. The Weibull model fitted very well to the observed frequency distribution of the wind speed data used in this research, mainly due the consistency of the Weibull parameters estimation. The lowest and the highest wind energy potential were observed at Maranhao and Rio Grande do Norte States, respectively. At Acarau, CE, was observed the highest wind energy potential, with 138.30 W/m2 . On the other hand, the lowest wind energy potential was register at Aalto Parnaiba, MA, with 0.02 W/m2 .