Reduction of wind power due to long term variation of wind speed In Esfehan province

Document Type : Original Article

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Abstract

Aiming to evaluate the wind power changes in Esfehan Province, wind speed variability of Esfehan and Kashan synoptic stations which have more than 40 years records, have been studied. Observation data on wind speed and wind direction in Esfehan station for period 2005-1961 and in Kashan station for 2005-1966 periods have been analyzed. Linear trend of annual mean wind speed for long term period with rate of 0.29 and 0.1 m/s per decade, for Esfehan and Kashan stations respectively, is assessed acceptable at the significant level of 0.05. By using Kruskal-Wallis statistical test, significance jump in decadal means of those time series has been issued. Comparing of mean wind speed for each of 12 months of the year and also different times of a day in two periods (long-term and 1992-2005), has shown a significant reduction of wind speed and thus the amount of energy for the long-term stations above. Changes in the distribution of wind speed and wind direction in terms of different time scales, also has been issued. For example, it can be pointed to reduction of wind speed in eastern South West (90 to 240 degrees) respect to the other directions and reduction of wind speed between 00:30 P.M. and 00:30 A.M. respect to other times of day in Esfehan

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References

 
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Nivar
Volume 34, 71-70 - Serial Number 71
September 2010
Pages 17-22

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History

  • Receive Date: 29 December 2008
  • Revise Date: 02 April 2009
  • Accept Date: 15 December 2009
  • First Publish Date: 23 September 2010

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