International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The increasing demand for electrical energy, the reduction of fossil fuel reserves, and growing concerns about environmental pollution have driven the development of technologies for energy production from renewable sources, particularly solar energy. The efficiency of photovoltaic systems depends on the angle of incidence of solar radiation on photovoltaic panels. Static systems cannot maintain the optimal orientation toward the sun throughout the day, resulting in reduced electricity generation. For this reason, mechanisms for automatic solar trajectory tracking have been developed, significantly improving the performance of photovoltaic systems. This paper addresses the design, development, monitoring, and operation of a single-pole dual-axis mechanism for solar trajectory tracking of the SM44M3V15P type, integrated with photovoltaic modules. The system was developed as a prototype and later implemented near the Mechatronics Laboratory at the Faculty of Mechanical Engineering, University of Prishtina. The mechanism enables continuous tracking of the sun’s trajectory through two independent axes: the azimuth axis and the elevation axis. The system includes linear actuators, a mechanical structure, electronic components, and software for automatic monitoring and control. The study includes experimental analyses and simulations to compare the performance between a fixed photovoltaic system and a dual-axis tracking system. The results show that the dual-axis mechanism significantly improves electrical energy production compared to static and single-axis systems. Annual energy production increased from 4156.13 kWh in the fixed system to 5487.42 kWh in the dual-axis tracking system. The findings demonstrate that dual-axis solar tracking systems represent an efficient and sustainable solution for improving the performance of photovoltaic installations in modern engineering applications.

Currently Uzbekistan has widely adopted drip irrigation systems on large-scale agricultural lands (1-100 hectares or more), and smaller plots cultivated by households and individuals for essential food production often lack this technology. To address this disparity, a novel mobile drip irrigation system incorporating photovoltaic panels has been engineered. This integrated solution is self-sufficient, requiring no external power source, and offers versatility suitable for both rural and urban settings. Its mobility allows for easy deployment on small plots (up to 1 hectare) commonly used for household gardens, suburban areas, and greenhouses. The integration of photovoltaic panel complexes with low-pressure mobile drip irrigation systems holds significant potential for ensuring a dependable water supply to agricultural crops. This innovative technology is particularly well-suited for regions facing water scarcity, such as Uzbekistan, Central Asia, and other arid zones globally, enabling sustainable agriculture practices even in the context of climate change.

The paper deals with an operating photovoltaic plant in Bulgaria. The wide application of photоvoltaic plants in the energy system is known. At the same time, subject matters about their normal functioning are fundamental. The goal of the paper set is to analyze data from the operation of a photovoltaic power plant , which is ultimately related to improving its behavior. Relevant conclusions have been dоne.

Experimental vitreous samples with the presence of self-cleaning coatings applied by the sol-gel method were selected, which were tested in a real environment under cyclic atmospheric conditions in different TPPs / TPP-Sofia and TPP-Republika, Pernik/. The resulting thin films were studied by UV-NIS – VIR spectroscopy, AFM, contact angle, etc. The experimental samples are potentially applicable in the operation of photovoltaic panels with increased efficiency and sustainability in the conditions of an industrial environment and under the influence of various meteorological factors.

A summary study of the development of solar energy and the main factors determining the productivity of photovoltaic systems has been carried out. The predominant surface contaminants of solar panels, reducing the efficiency of photovoltaic installations, and the existing different design types of cleaning systems for their effective removal are examined. The main trends in the development of singlelayer and multi-layer hydrophobic and other oxide coatings with diverse performance indicators suitable for solar panels are traced. In laboratory conditions, experimental self-cleaning coatings (based on compositions with the participation of Y2O3 and ZrO2) deposited by the sol-gel method on vitreous samples were obtained. The structure and morphology of the prepared thin films and the technological conditions for the deposition of nanoscale layers with different functional characteristics were investigated. The experimental results represent a prerequisite for the development of a series of additional compositions and a detailed technological regime for obtaining various modifications of resistant, long-lasting self-cleaning coatings, potentially applicable to photovoltaic panels.

The aim of this paper is to review the cleaning of solar photovoltaic (PV) systems and applied coatings that eliminates costly automated cleaning systems by using nano-sized TiO2 combined with various organic binders.