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Bankable AEP assessment

Wind statistics at the turbine hub are converted in power using the power curve of selected turbine models obtaining the gross Annual Energy Production (AEP). Declared power curve from the turbine manufacturer are individually corrected based on the average air density at every turbine site. Information on air density is derived from measurements or meso-scale data for the site. Single turbine array losses by direction are determined using analytical wake models. This approach includes the wake effects in the wind field as a post-processing step. Other technical losses like turbine availability, electrical losses, icing etc. are assessed based on traceable experience and industry standards in order to obtain the net AEP or P50. The degree of uncertainty in the calculated wind resource is assessed as a combination of different factors like wind speed measurements uncertainty, their relation to the historical wind climate, inter-annual variability, and horizontal and vertical extrapolation.
Wind uncertainty is converted to uncertainty in AEP through a multiplication with a sensitivity factor. Other standard uncertainty sources in power production are assessed and added to estimate the total uncertainty of the process chain (measurement + modeling) and therefore the energy production with higher probability (P75, P90).