Geofizika, Vol. 8 No. 1, 1991.
Short communication, Note
Hourly values of solar irradiation in clear skies
Ivan Penzar
; Department of Geophysics, Faculty of Science, University of Zagreb, Zagreb, Croatia
Branka Penzar
; Department of Geophysics, Faculty of Science, University of Zagreb, Zagreb, Croatia
Abstract
Hourly values of global solar irradiation in clear skies are determined as a function of solar elevation using empirical parameters derived from the measurements of radiation in Zagreb (f = 45.828° N, l= 15.992° E) in the period between 1960 and 1985. The estimation was performed on the 15th of every month for geographical latitudes between 41° and 46° N. By means of the well known procedure the global solar radiation is then divided into the direct and diffuse solar radiation and calculated for a south-facing surface inclined at 35°. A possibility of taking into consideration the influence of clouded sky on the decrease in the clear-sky solar irradiation is also presented.
Keywords
Hrčak ID:
20631
URI
Publication date:
1.12.1991.
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