• Energy Research

This work presents the results of a study of the electrical-power characteristics of a thermophotovoltaic solar collector, the receiving surface of whose photocells was modified using a plasma-electrolytic coating made of silver nanoparticles dispersed by a pulse-spark method. An improvement was found to the functional properties (efficiency and power) of the modified photoelectric converter, which operated as a part of the thermophotovoltaic device.

This article presents the results of a study of a combined wind–photovoltaic installation for use in the energy sector of the Republic of Iraq. The presented hybrid system is proposed for providing energy to utility customers in Iraq and for its energy sector. Iraqi consumers are experiencing a constant shortage of electricity, and the proposed solution for joint generation of energy by wind–solar installations will help solve this problem. The authors show a total increase in the efficiency of the mini-energy complex due to the combined generation of electric energy by converting the wind flow and solar radiation. This study is devoted to the analysis and modeling of a small autonomous hybrid wind–solar energy system. During the study, parameters such as the angle of inclination, rotor diameter, wind speed, etc., were considered. The simulation of the photovoltaic installation is carried out under nominal conditions, such as the temperature of the silicon cell, solar insolation, etc. The MATLAB computer program was used to describe the mathematical models of small horizontal axes of wind turbines and photovoltaic systems. An experimental study was carried out using low power installations. The research results show that when using hybrid wind–solar systems to provide the energy complex in Iraq, the total production of the hybrid installation increases significantly. Moreover, the generation of electric energy by wind and solar installations in different months of the year is different. Those in the summer months, mainly photovoltaic batteries operate, and in the winter months, wind turbines make the main contribution to energy generation. As a result, the joint work of wind and solar installations to generate electrical energy helps to establish more uniform generation throughout the year. Such hybrid systems increase the reliability of the energy complex based on renewable energy sources. The introduction of the presented systems to provide individual consumers seems promising in the field of alternative energy.

This paper presents a brief analysis of the photovoltaic (PV) modules that are currently commercially available. The most used calculation formulas and measurement procedures used for evaluating the power characteristics of photovoltaic PV modules are given. The possible causes of power losses of solar cells and modules are described, including losses caused by design features. The theoretical calculations and experimental results of measuring the characteristics of silicon PV arrays with changing surface irradiance are compared. The calculated and experimental dependences of the power output variation of the ISM-50 photovoltaic module with changing its tilt angle are presented. It is shown that there is a significant discrepancy between theoretical studies and experimental results. A hypothesis has been put forward about the dependence of a real decrease in power characteristics and refraction indices of PV array protective coatings. An adjustment factor is proposed taking into account the decrease in the solar radiation output on the silicon photocell surface when passing through the antireflective protective coatings of the PV module. The conclusions drawn from the results of this work indicate that the identified factors affecting the electricity generation by photovoltaic converters need to be considered.