Evaluation of anti-icing energy and power requirement for wind turbine rotors in cold climates

Interest in the icing problems of wind turbines and in predicting the effect of icing on power generation has increased significantly in very recent years. The reliable prediction of the power and energy required to operate ice prevention systems (IPS) to ensure safe operation under icing conditions is of practical importance for the competitive design of WECS, because it furnishes a basic input for break-even analysis. Such a prediction is not easy to achieve, however, because of the complex dependence of the IPS power and energy requirement on site meteorology and turbine (structural and functional) variables. A simple, but reliable model is presented here for estimating the anti-icing heat requirement and on-board installed power needed to operate thermal ice prevention systems fitted on wind turbine rotors installed in cold climates. The model evaluates the yearly energy required to heat the blades and the anti-icing power demand on the basis of probability distributions of site meteorology parameters. Representative site velocity and temperature during icing events, calculated by using probability distribution properties, are input in a simplified relationship accounting for the thermal model that evaluates heat fluxes and the icing time. The model has been validated with calculations performed by input a wide range of icing parameters distributions.