Analysis of the diffuse fraction from solar radiation values measured in Argentina and Brazil sites

MANOEL HENRIQUE DE OLIVEIRA PEDROSA FILHO; SALAZAR, GERMÁN A.

Santiago de Chile

Congreso; ISES Solar World Congress 2019; 2019

The knowledge of the spatio-temporal characteristics of the components of solar radiation is of importance to optimize its practical application, mainly for direct component, which is the one that can be concentrated. But, since most of the meteorological stations in the region only measure global radiation, the correlations between it and diffuse component are studied. In this way, from the measured values of global solar radiation, diffuse component can be estimated, and horizontal direct component can be calculated. In this paper, values of global and diffuse fractions measured in La Quiaca (Argentina) and Araripina (Brazil) are analyzed, with a recording frequency of 1 minute, adjusted according to a sigmoidal function. Qualifying data filters were applied to guarantee that invalid values cannot be used in curves adjustment. Hourly and daily partitions are analyzed, and its coefficients are obtained. Comparing the hourly curves to 5 other sites, it was noted that all curves are interlaced what indicates a quite similarity of relation behave. Daily curves were also obtained, it was verified that they are similar