Numerical Methods to Calculate Solar Radiation,Validation through a New Graphic User Interface Design

The aim of this paper is to validate and evaluate the performance of the most appropriate models for estimating global radiation by confronting meteorological techniques to selected semi empirical methods. Author also provides a friendly Graphic User Interface ‘GUI', carefully designed making use of a large range of models for the calculation of solar components through the approach based on ground measurements and thereby allows testing the theory by numerical simulation. This provides information on the situation of solar applications in a given site and contributes to improving the performance of solar energy systems. This study supports three numerical models namely the models of Lacis& Hansen, Atwater & Ball and Lui& Jordon which calculate hourly global radiation. They are used here to guess the performance of such methods facing meteorological models such as those of Angstrom, Garg and Coppolino. One of the most important atmospheric conditions is involved in this latter case that is the water content in the atmosphere. This parameter is particularly important because it strongly absorbs solar radiation in the infrared region. These methods are also of big importance because they suit perfectly the nature of many measurement networks characterized by a lack of radiometric stations but which provide sunshine duration data. The data used in this paper correspond to measurements of sunshine duration, temperature, relative humidity and global radiation. They are supplied by the Unit for Applied Research in Renewable Energy -UARRE- (Ghardaïa, Algeria, 3.80 °E, 32.4°N). This selected station is especially interesting (situated a hundred kilometers far from the famous hybrid (solar, gas) station of HassiR'Mel). It is also the best in terms of fulfilling criteria such as smooth operation of its equipment’s as well as reliable measurements with almost inexistent missing data. In all cases, comprehensive comparative studies are carried out using experimental measurements. The results are obtained with attractive margins of error and in accordance with experimental measurements. Interesting comparisons are made possible thanks to an ergonomic and convivial Graphic User Interface carefully designed in the present work, for such purposes and similar.