The present work shows an alterative method for determining the tracking energy advantage, defined as the additional electrical energy produced by two axes tracking systems respect to fixed devices, in order to analyze the economical profitability in Spain. For this purpose, 52 main cities of this country have been analyzed. The proposed methodology starts from irradiation data, combining diffuse models and daily-hourly relations. Different types of losses have been evaluated, and the electrical behavior of the systems has been incorporated. Final annual energetic results demonstrate that two axes devices show a relevant energy advantage (higher than 20%) for most of the national territory. (C) 2011 Elsevier Ltd. All rights reserved.