Journal of Solar Energy Research
Volume:2 Issue: 2, Spring 2017

Nowadays, shortage of the water resources is a global issue. Water desalination is a solution that can be used to solve the water shortage problem. Several methods have been proposed for water desalination and are categorized to membrane and non-membrane procedures. The most popular membrane processes are electrodialysis (ED) and reverse osmosis (RO); in contrast, the most popular non- membrane processes are capacitive deionization (CDI) and distillation. All water desalination procedures need energy supplies. The solar and Photovoltaic (PV) energy is potentially a desirable green energy supply for water desalination especially for non-residential areas where the grid is not available. In areas such as deserts and offshore stations, the PV solar energy is a practical and cost effective solution for water desalination systems. Where the grid connection is available, the PV and solar desalination systems produce fewer emissions. The PV energy needs to be processed through power electronic power conditioning systems. This paper proposes the application of PV power and solar energy to supply the water desalination systems.

Photovoltaic (PV) systems offers clean source for the generation of electricity, which is however costly today. Due to the variable and stochastic behavior of the solar energy resource, Maximum Power Point Tracking (MPPT) of photovoltaic systems is required to ensure continuous operation at the maximum power point to generate the most electrical energy. This paper presents the use of a model predictive controller (MPC) considering constraints for safe operation in order to maximize the power output from a PV system. Analysis and simulation of the proposed system is discussed in details through the paper. The simulation results show that the designed controller can track Maximum Power Point quickly, accurately and effectively.

It is reasonable to answer to the question: is the rule of thumb, which says that solar collector should be orientated towards the Equator with a tilt equal to latitude, is valid for high latitudes region in Southern Hemisphere? In addition, the question that may arise: how many times is reasonable for adjusting collector tilt angle for Equator facing collectors? A mathematical model was used for estimating the solar radiation on a tilted surface, and to determine the optimum tilt angle and orientation for the solar collector at any latitude. This model was applied for determining optimum tilt angle in the high latitudes zone in the Southern Hemisphere, on a daily basis, as well as for a specific period. The results reveal that changing the tilt angle 12 times in a year maintains approximately the total amount of solar radiation near the maximum value that is found by changing the tilt angle daily to its optimum value. This achieves a yearly gain in solar radiation up to 1.8 times of the case of a horizontal surface while the daily gain reaches 60 times approximately. Moreover, general formulas are proposed for predicting daily optimum tilt angle and optimum tilt angle over any period.

In order to use photovoltaic cell effectively and improve its photoelectric conversion efficiency, the maximum power point of photovoltaic generation system should be tracked rapidly and stably. In this paper after comparison and analysis common methods used in controller of photovoltaic systems such as Fuzzy and P&O, proposed an approach combined from FLC and particle swarm optimization algorithm (PSO) as an appropriate method to achieve maximum power point tracking (MPPT). Indeed Fuzzy logic control can cope with photovoltaic system using heuristic knowledge rules, but tuning the control parameters is not straightforward. PSO performs an on-line haphazard global search for input and output scaling factors of a PD-type fuzzy controller. The objective function of the PSO algorithm has been defined to minimize slope of P-V curve. The simulation results in SIMULINK of MATLAB indicate that proposed method can effectively eliminate the power oscillation around MPP and raise stability and reach steady state of the system.

A novel micro solar combined heating and power (CHP) cycle integrated with organic Rankine cycle (ORC) is proposed in this study. The thermal storage tank is installed to correct the mismatch between the supply of the solar energy and the demand of thermal source consumed by the CHP subsystem, thus the desired system could continuously and stably operate. The cycle is investigated and optimized from the viewpoint of thermodynamics and thermoeconomics. In base case design, the thermal efficiency, exergy efficiency and product cost rate are found to be 48.45%, 13.76% and 5688.1$/year. The thermal efficiency, exergy efficiency and product cost rate are selected as three objective functions and multi-objective optimization is carried out through Genetic Algorithm.

Due to the growing rate of the cost of energy carriers and the shortage of different kinds of fuels, day by day it becomes more essential to use renewable energies such as wind, solar, hydrogen, geothermal, etc. The application of renewable energies for household use is an ideal solution to reduce enviromental pollution. It is possible to use different kinds of renewable energy systems either single or hybrid. Because of the fact that by using the single method it is not possible to use any kinds of these energies in a continuous way, so it is better to use the hybrid system in order to use these energies in a continuous way. In this paper an ordinary household user in Tehran is studied for the feasibility and financial optimization of the PV-wind renewable hybrid energy system by HOMER[1] ENERGY software. Also, the results are analyzed and compared with some other cities with their own data. The optimization results contain the number of components and primary costs. In this designed system for the specified user, the price of electricity generated per kWh is given by the software and equals to 22.4 cents. The price of electricity per kWh which is generated and sold in Iran almost equals to 10 cents. Due to the advantages of renewable energies for the enviroment, it is cost effective to use PV-wind hybrid energy system. A storage system is also considered to store the excess energy produced by the hybrid system. Also, during a 25-year period, all the costs which are used for this system are returned back.

In this article, it is aimed to bring an intellectual declination to the aspects of “solar energy” deeply affecting the future of urbanization and planning activities and accordingly, the changes that may occur in urban macro form. The changes that may emerge in the forms of producing and consuming the energy naturally affects the urbanization process in addition to technological a socio-eonomical developments. The process should be evaluated through totalitarian developments. When the complexity of the matter is considered, deep theoretical declination is required. In this sudy, the references and basic resources which haven’t been explained in detail within the text for technological developments and biotope of the future were employed. The purpose of the study is to share our estimations about the demands of those developments and legal, administrative, and social behavior patterns that is required to occur accordingly not make interpretations about “technical” dimensions which require expertising on solar energy. In addition, we also aim to come up for discussion about important ontological problems we regarded vital in the relationships between energy and city. As a result of those discussions and researches, it is a beginning that is hopped to provide contributions to change the planning paradigm.

In this paper, detailed exergy and energy analysis of selected thermal power systems driven by parabolic trough solar collectors is presented. solar energy is used to feed a two stage steam Rankine cycle to supply domestic hot water. To determine the irreversibilities in each component and assess the system performance, a parametric study is performed to investigate the effects of varying design parameters and operating conditions such as the effects of the ambient temperature, solar radiation, and high pressure turbine pressure ratio and solar cycle mass flow rate, on the system energy and exergy efficiencies. An optimization with an evolutionary algorithm is applied to determine the best exergetic performance. This study reveals that the main source of exergy destruction is the solar collector where contributes more than 45% of total exergy destruction. In addition, heater, condenser and heat exchanger contribute to 16%, 15% and 14%, respectively. Finally, this study reveals that optimization using genetic algorithm improves the exergy efficiencies up to 58.03%.