Climatology of North Sea wind energy derived from a model hindcast for 1958-2012

Abstract

Model-based wind speed data derived from the coastDat2 data set for the North Sea were used to assess wind power potential considering both spatial and temporal variability. The atmospheric part of coastDat2 was simulated with the regional climate model COSMO-CLM 4.8. The quality of the used wind speed data is analysed by comparison with buoy and QuikSCAT data. To determine where an offshore power plant can be cost-effectively developed, the distribution of the possible production dependencies on the offshore distance is one of the more important factors. A synthetic power function was used to convert the model-derived wind speeds at a height of 100 m to wind power. The data were analyzed for the period of 1958–2012, and the results obtained for the decadal and spatial variability were mapped. The site related summaries are discussed. The inter-annual to decadal variability can reach up to 5% from the multi-decadal mean and therefore plays an important role in wind energy; wind power estimates based on short observational time series, particularly from the late 1990s, may exhibit high biases. The up-scaling from wind speeds at a height of 10 m using conventional power laws may result in similar biases. On inter-annual to decadal time scales, synergies are not expected from the different arrays in the North Sea, i.e., a decrease in the power output of an array may not be balanced by another.