Journal of Solar Energy Research
Volume:5 Issue: 4, Autumn 2020

In this paper, a system of simultaneous production of power and heat and cooling in a Kalina cycle has been analyzed by energy, exergy and economic aspects. To provide heat in the cycle heating unit, four types of solar thermal linear (PTC) and linear share (LFR) heat collectors, plate (dish) and vacuum tube, have been used. The results of the analysis of this cycle for the PTC collector compared to other collectors showed that this collector was superior in increasing the energy and exergy efficiencies of the system and also lowering the total cost rate and exergy destruction of the CCHP cycle. By using parametric studies tried to obtain the effect of increasing and decreasing some of the cycle component parameters to get the most cooling, heating and power output.

Desalination could be a sustainable solution for responding to the ever-rising demand for water and the scarcity of freshwater resources. But given the substantial energy consumption of conventional desalination methods, greater use of renewable energies such as solar in this area seems inevitable. This study investigated the effect of placing sand within the basin of a simple basin-type solar still on its performance. For this purpose, two solar stills one with a sand-containing basin and the other without sand, were designed and constructed. The stills were then tested in Sabzevar (latitude: 36.20; longitude: 57.67), Iran, to determine the effect of sand. The tests were carried out over three days in early July 2019 for 13 hours each day. The results showed that the presence of sand within the basin of the still increased its water productivity and thermal efficiency by 21.16%. Considering these results and the low cost and high availability of sand, placing sand inside the basin of the solar still appears to be a good solution to increase its efficiency.

In this study, ZnFe2O4, ZnO nanoparticles and nanocomposites of ZnFe2O4–ZnO (core-shell) have been made via simple coprecipitation manner which is a rapid, inexpensive and economical method, impact of green surfactants such as red pepper, black pepper, lemon, saffron, as well as carbohydrates like gelatin, poly vinyl pyrrolidone, glucose, on morphology of ZnFe2O4 were investigated. These surfactants are known as biodegradable and biocompatible factors, moreover, the effect of concentration, temperature and sediment agent on the surface characteristics of core magnetic have been studied and outcomes of SEM analysis indicated that the organic solvent of the red pepper possesses a great effect on diminishing size of nanoparticles. VSM analysis emphasized that ZnFe2O4 and desired nanocomposites possess super-paramagnetic property and analysis such as X-ray and FT-IR spectroscopy were used to indicate pure nanoparticles and nanocomposites. As well photo-degradation of toxic dyes was applied under solar irradiation.

Daylighting has always been the central focus of designers. Today, due to economic, health, and environmental concerns, daylighting has taken on paramount importance. However, due to location and architectural restrictions, the use of natural light in all interior spaces is a challenge facing architects. Today, although the development of modern lighting systems has contributed to a solution to this problem, the provision of necessary conditions for more efficient daylighting necessitates a thorough understanding of all types of lighting systems and plans. This study aimed to further link technology and architecture to take the required steps to solve the shortage of interior daylight by comparing and selecting appropriate daylighting systems and plans. To this end, we first studied various modern lighting systems and analyzed their characteristics to prioritize and select their most efficient elements and factors. In this regard, the FGD method was used to identify criteria and sub-criteria. Then ANP was used to analyze and compared to identify the most optimal ones. In the next step, we studied different types of office plans to prioritize them based on the aforementioned elements. It is worth noting that to validate the results, we surveyed experts in the field. In the last step, we studied compared the compatibility of different plans and systems to achieve the most compatible ones.

For preparation of an effective sunscreens three nanoparticles were added to the matrix for suitable improving of sun absorption. In this study, different types of hollow TiO2, ZnO, Fe2O3 were synthesized by sol-gel method. To prepare TiO2 nanoparticles, tetra isopropoxide (TTIP) was used as a precursor and methanol as a solvent and its photocatalytic properties were investigated. Colorants and industrial wastewater were used to study photocatalytic properties of pure titanium dioxide, zinc oxide and iron oxide. The prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectroscopy and UV-vis absorption. All the synthesized products were used for preparation of sunscreen cream composite.

In the present paper, the possibility of using thermoelectric power generating modules (TEG) to convert the heat generated by the photovoltaic / thermal collector (PVT) to electricity in Iranian cities has been investigated. Thermal modeling of PVT-TEG system has been performed. The hot side of the TEG module is connected to the top of the air duct, which is connected to the back of the solar panel. Air flows through the duct and cools the cold part of the TEG modules. TEG modules convert the generated temperature gradient into electricity. Therefore, generating additional electricity from the generated heat improves the performance of the system. To evaluate the performance of the PVT-TEG system, nine cities with different climates from Iran (Bander Abbas, Birjand, Bojnurd, Bushehr, Esfahan, Hamedan, Jask, Kerman and Kermanshah) have been considered. Meteorological data for each city were used for the studies. The results show that the efficiency of the system depends on the temperature and the intensity of radiation. The electricity produced by the proposed system in Kerman is 1.66 times that of Bojnurd. Increasing the number of TEG modules increases the amount of electricity produced. Kerman city has the highest TEG efficiency (1.58%)and Bojnurd city has the highest PVT efficiency(9.15%).