Journal of Solar Energy Research
Volume:2 Issue: 4, Autumn 2017

Iran owns various resources for energy production, including natural resources and land. Although the country holds one of the biggest fossil fuel reserves, the country's development plan and international commitments requires the reduction of GHGs and the implementation of clean energy generation. Despite the various plans and institutional support, the country's dependency and trajectories for investment on oil industry, cheap resources of fossil fuels, the lack of infrastructures and technology are the main barriers for this transition. Governmental support, CO2 pricing and foreign investment (associated with technology imports), are the proposed methods for overcoming the barriers and to facilitate the transition process to renewable energy resources.

This study embraces a steady numerical simulation of thermodynamic model optimized for an ammonia-water diffusion absorption refrigeration (DAR) cycle with hydrogen or helium as the auxiliary gas. A DAR cycle has been examined due to the fact that such cycles may operate under low cooling load without a mechanical pump. To this end an Electrolux refrigerator manufactured by Dometic of Sweden is examined. The generator of this system has been modified to have it coupled with a parabolic trough collector in order to enhance the heat transferred to the generator. Besides, considering temperature range gained by the collector, the DAR cycle has been optimized. Finally, the results are validated against available experiments. It was found that the effects of parameters such as generator temperature, ammonia solution concentration, pressure of the cycle and the temperature of the main components of the cycle can change the COP by ±10% .

Agriculture is a main part to global warming through greenhouse gases because of activities such as deforestation, soil treatment and methane emissions from livestock. It is also one of the main users of fossil fuels; it means contributing further to greenhouse gases emissions. Both increased energy demand and reduction of fossil fuel reserves, have encouraged the interest for development of new technologies as renewable energies (RE). Renewable energy started to become a feasible solution. One of the most important kind of RE is solar energy. The solar devices will be able to help improve health and local economies. Solar water pump can be one of the most important and applicable devise in farms specially where there is no existing power line. Photovoltaic water pumps are very reliable and require little maintenance. In this regard, the present study has been conducted to investigate the role of photovoltaic water pumps in development of agricultural sector.

In this paper, a grid connected solar photovoltaic plant has been proposed, and its performance has been evaluated. The performance analysis has been done on a designed 100kW grid connected solar photovoltaic plant in the Semnan city. The simulated system comprises 625 CIS PV modules. Each PV module has a rating of 160Wp. All the PV modules are arranged in 25 strings, with each string made up of 25 modules in series. Two solar inverters, each having a rating of 50 kW are used for interconnecting with grid. The 100 kW PV system generates 178.99 MWh/year, wich 170.3 MWh/year is injected into the grid. The performance ratio and its total impressed losses have been calculated. The performance ratio of 100KW solar plant in Semnan city obtained 83%. Finally, the simulation results indicate that the designed solar power plant will prevent 171 tons of gas CO2 from being produced during 30 years.

In the last decade, graphene as one of the novel engineering materials with unique properties has been strongly considered by researchers. Graphene based supercapacitors and transistors are one the most recent subjects in the case of solar energy system fields. In this study, five main methods of the grapheme synthesis including micro-mechanical cleavage, liquid-phase exfoliation, graphene via graphite oxide, graphene from mechanical milling of graphite and electrochemical exfoliation of graphite have been investigated which are in the challenge of engineering and economics justifiable in using for supercapacitors. Subsequently, the liquid-phase exfoliation has been chosen as the best method of producing graphene for using in supercapacitors in the industry scale based on the investigations and comparison throughout the advantages and limitations of the preceding methods.

In this paper, numerical simulation of perovskitesolar cells (PSCs) for two structures (direct and inverted) and two perovskites (MAPbX3, MA: CH3NH3, X: I, Br) had beendoneby SCAPS software. Thickness of active layers (the perovskites) have beenoptimized by using PCE curvesand then,electrical properties of the solar cells have beenextracted. Results of simulations showthat the best structure is inverted structure with active layer MAPbI3which characteristics of the structure are 15.4%, 24.68 mA/cm2, 8.48 V, and 73.74% for PCE, JSC, VOC, and FF, respectively. In addition, study of donors or acceptors density demonstratethat the parameter is so effective on performance of solar cells and PCE achieved to 18% by increase in the parameter.

Nowadays, with the population growth, renewable energies- especially solar energy- have grown effectively among governments. These types of energies are considered to be unlimited sources of energy and have the least harmful effects on the environment. In recent years, investment in the solar energy has been rising rapidly in Iran. One of the important challenges in this field is the site selection of solar power plant which is encountered with many spatial and environmental considerations. The contribution of this research is to determine the suitable site for the creation of a solar power plant in Jiroft and Bam cities of Kerman province, using GIS and fuzzy DEMATEL. In this study, six main criteria including solar radiation potential, surface temperature, access to urban areas, access to transportation lines, slope and aspect, were used. Finally, the study area is classified into four categories as “low suitable”, “moderate”, “best suitable” and “not suitable” with an equal interval classification method. The results showed that 8% (1218.282km2) of the study area has low suitable, 14.23% (2406.903 km2) has moderate suitable and 12% (1996.311 km2) has best suitable for solar power plant area. 66% (11291.03 km2) of the study area is not suitable for solar power plant.

This study deals with a cascade organic Rankine cycle driven by linear Fresnel solar collector as a source and cold energy of LNG to produce power. An exergy concept is used to model the system and the performance of the desired system is assessed by varying the major design parameters namely solar subsystem feed mass flow rate, LNG mass flow rate and turbines inlet and back pressures. A Parametric study shows that among the design parameters solar subsystem feed mass flow rate and turbine 1 back pressure have positive effects on the performance of the system and maximum efficiencies increments are achieved within 5.24% as turbine 1 back pressure increases.