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In this work the impact of sunlight intensity and ambient temperature on the inorganic solar panels in winter climate (22 November 2015) at Sarwchawa, Kurdistan Region, Iraq was carried out. A maximum intensity of sunlight (106.25 klux) was reached at 12:00 PM. However, beyond 12:00 PM the intensity showed a non-monotonic change behavior. This was ascribed to the change of sun position, its orientation and the direction at which the surface of the panel is illuminated. Results showed that the increase of sunlight intensity has made Isc to increase, while that of the Voc remains relatively unchanged. The reason why Isc is more affected by the sunlight intensity was understood from the fact that charge carriers acquire enough kinetic energy to move towards their corresponding electrodes before they relapse or recombine together, while as Voc is mostly correlated to the energy gap. There was a trivial decrement of efficiency with the increase of temperature. This was where the FF showeda reverse trend of increment with the increase of temperature. Noteworthy, at the points where the fill factor was decreased the efficiency was increased and vice versa.

In this research work a small thermal engine was utilized for generation of electrical energy and its operation was analyzed in terms of the output performance with various external load resistances and different flywheel rotations. It was seen from the results that with increase of the external load there is a less considerable increase in voltage. It has been observed that by an increasing the external load from 100 Ω to about 2000 Ω, a rapid decrease in the output power is occurred. However, beyond a specific value of about 2000 Ω the decrease in the electrical power is relatively small. It was obvious from the results of output voltage, current and power with respect to the increase in hot air temperature (T1) that these physical quantities are increased at a constant rate for specific range of temperatures, from 185 °C to about 240 °C. It was worth mentioning that at higher temperatures the rate of increase in output voltage was reduced, implying that the expansion rate of hot air is getting saturated and the rotating speed of the flywheel reached its maximum capability to generate electricity.

This work reports on the impact of surface morphology on the optical absorption of vacuum deposited tris (8-hydroxyquinoline) gallium (Gaq3) films. Morphological investigation was performed for films treated under nitrogen gas in the temperature range from 85 °C to 255 °C. The results of field emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD) technique ascertained the formation of amorphous nanostructures. Considerable modification in the absorption behaviour of Gaq3 films was observed upon morphological changes. The results of these modifications were ascribed to the impact of morphological variations among the surface of Gaq3 films.