Extreme Wind Calculation Applying Spectral Correction Method – Test and Validation

We present a test and validation of extreme wind calculation applying the Spectral Correction (SC) method as implemented in a DTU Wind Condition Software. This method can do with a short-term(~1 year) local measured wind data series in combination with a long-term (10-20 years) reference modelled wind data series like CFSR and CFDDA reanalysis data for the site in question.

The validation of the accuracy was performed by comparing with estimates by the traditional Annual Maxim a (AM) method and the Peak Over Threshold (POT) method, applied to measurements, for six sites: four sites located in Denmark, one site located in the Netherlands and one site located in the USA, comprising both on-shore and off-shore sites.

The SC method was applied to 1-year measured wind data while the AM and POT methods were applied to long-term measured wind data. Further, the consistency of the SC method was validated from the variance of the extreme wind prediction when different years are used as the period of the short-term measured wind data.

For all six sites, the SC method was found to be quite accurate and very consistent when applied to one-year on-site wind data periods. It is concluded that the SC method in combination with widely available long-term reference data is a valid alternative to estimate extreme winds in cases where only short-term on-site measured wind data are available.