Power and Wake Losses at Vestavind F

This study investigates the effect of wake losses on the Annual Energy Production at the Norwegian offshore wind site Vestavind F.  Three different scenarios of wind farm layouts consisting of turbines of the 5 MW, the 10 MW, and the 15 MW class, respectively, are analysed. Eleven years of historical wind data produced by the Norwegian reanalysis wind dataset NORA3 are used as a time-domain input to compute both the wind farm’s power production and the associated production losses due to wake flow interaction. The computations show a substantial year-to-year variation in both wake losses and energy production. The annual wake losses show an inverse relation to the annual average wind speeds and power production. The total wake losses of the 10 MW farm layout show large year-to-year variations from a minimum of 0.53 % to a maximum of 15.60 % of the total production. These significant fluctuations could be primarily attributed to substantial differences in annual average wind speeds at the investigated location. Furthermore, the turbine types' thrust coefficient and rated wind speed are seen to influence the amount of wake losses.This study highlights the necessity to use meteorological input data of one decade or more to predict future Norwegian wind farms fluctuating energy production and their associated wake losses.

Presenters

Daniel Sukhman, PhD-fellow, Høgskulen på Vestlandet (HVL)

Jan Bartl, Associate Professor, HVL