A simple model to predict the energy loss due to leading edge roughness

In this paper a simple model to predict losses in annual energy production due to leading edge roughness or leading edge erosion from wind turbines is presented. Because detailed information about wind turbines not always are available, the input to this model requires only a few parameters: rated power, rotor radius, two Weibull parameters and categories of local damages. Therefore, some assumptions are made in the model. It was validated against a common implementation of a BEM code and showed good agreement in the loss of annual energy production. Also, a categorisation methods was proposed. The categories ranged between a and e corresponding to an undamaged blade and a severely damaged blade, respectively. This categorisation was made locally on the blade. The blade is divided into annular elements and each annular element is graded with a category. By summing up the annular elements on the blade, each with their categories, the total loss in energy production was predicted.