A model of side pumping technique for a system of solar concentrators was performed for laser generation. Measurements for the total solar radiation in the hot desert area near Helwan which is south of Cairo by 30 km, of latitude 30°N and longitude 31°E were carried out. The instruments were installed on the rooftop of the National Research Institute of Astronomy and Geophysics (NRIAG). The measurements indicate that the annual average of the global solar radiation is 5·21 kWh/m²/day, direct solar radiation is 6·26 kWh/m²/day, diffuse solar radiation is 1·86 kWh/m²/day, the clearness index K_t is 0·61, and the diffuse fractionK_D is 0·37. The performance of the laser rod and the performance of the system as a whole were tested. Finally, the measurements of solar radiation were applied to the model to obtain the behaviour of the laser output in different seasons, assuming that the concentrator system tracks the sun.

A study of the hourly, monthly, and annual variations of global and ultraviolet solar radiation and the meteorological parameters over a period of four year (1989–1992) over Cairo (30·05°N, 31·17°E) and Aswan (23·58°N, 32·47°E) in Egypt has been done. Measurements were carried out using Eppley ultraviolet radiometers by the Egyption Meteorological Authority. The global solar radiation was recorded using Eppley pyranometers. The correlations between the atmospheric transmission of ultraviolet solar radiation and clearness index and between ultraviolet and global solar radiation for Cairo and Aswan was also done. The correlations between the different variables by the linear regression analysis to estimate an empirical function relating global radiation to ultraviolet radiation and the meteorological parameters (temperature, water vapour pressure, and cloudiness) and a comparitive study between Cairo and Aswan has also been successfully carried out.