Abstract :
Several authors have analysed the changes of the probability density function of the solar radiation with different time resolutions.
Some others have approached to study the significance of these changes when produced energy calculations are attempted. We have
undertaken different transformations to four Spanish databases in order to clarify the interrelationship between radiation models and
produced energy estimations. Our contribution is straightforward: the complexity of a solar radiation model needed for yearly energy
calculations, is very low. Twelve values of monthly mean of solar radiation are enough to estimate energy with errors below 3%. Time
resolutions better than hourly samples do not improve significantly the result of energy estimations.
2007 Elsevier Ltd. All rights reserved
