Research Abstracts 1994-1995: Report No. 95-01

Walker, S.N. and P. L. Barbour, "Sub-Hourly Wind Data Assessment - Juniper Point, Washington," OSU Wind Research Cooperative, WRC Report No.95-01, March 15, 1995, 74pp.,$18.50

The need exists to understand more about the behavior of the wind on time scales less than one hour in the Pacific Northwest's complex terrain.  A data set of one0minute averaged windspeed and direction for Juniper Point, Washington was volunteered to the OSU Wind Research Cooperative for analysis by fellow WRC member FloWind Corportation.  This data set after screening, consisted of 11 days of one-minute averaged windspeed and direction data for three sites.  Basic time series statistical and frequency domain analyses were performed on this data.  The wind speed data was converted to simulated power output at three sites and the combination of power output examined.  the implications of array size upon power output variation was also studied.

Several obsetvations were made in reference to this specific data.  Caution should be exercised when generalizing these observations to other time periods or locations.
 

1. Data needs to be samples for averaging periods of five minutes or less to examine power output variations.
2. For energy calculations, hourly averaging sampling is a reasonable approximation until more sophisticated wind turbine dynamic modeling tools are available.
3. A reduction in the power output variance attributable to the sub-hourly wind characteristics may be obtained by increasing the number of turbines and the accompanying spatial diversity.
4. The rate of power change-frequency distribution is altered when sites are combined.