Applied Solar Energy

In this study, a solar panel is modeled and parametric simulation studies are performed with Ansys-Electronics 2019 R2 software according to atmospheric and temperature coefficient parameters that affect the efficiency of electrical energy produced in photovoltaic (PV) systems. Based on parametric simulation studies, 482 data of the voltage value of the electrical energy produced were obtained. Then a certain part of this data was used for training in Adaptive Network Fuzzy Inference System (ANFIS) algorithms and the system was tested with the estimated values produced. Thus, in the generation of solar and electrical energy, the duty ratio controller performance designed with an uninsulated DC–DC converter circuit proposed to generate a 400 V constant value DC bus voltage at the output due to voltage changes at the input is reported.

This work presents the structural and morphological characteristics of antimony selenide (Sb₂Se₃) thin films, which were deposited by the chemical molecular beam deposition (CMBD) in atmospheric pressure hydrogen flow on an alkali glass substrate. It was found that the deposition temperature affected the morphology and structure of the films. At a low deposition temperature of 720 K, the film depicts a preferable crystal orientation (211), i.e., one-dimensional (1D) Sb₂Se₃ ribbons are aligned along the growth direction. Morphological studies show that the grain size increases with the temperature of the substrate; however, the 1D Sb₂Se₃ chains tend to align along the lateral direction. The Sb₂Se₃ films were found to have a preferable orientation (211) and polycrystalline structure. At higher substrate temperatures of 770 and 820 K, they also have a polycrystalline structure, but with an orientation (120). The studies of surface morphology show that at low substrate temperatures the samples have fine grains that have sizes of (200–300) nm, but are rather tightly packed and have 1D Sb₂Se₃ chains, which are aligned along the growth direction that corresponds to the orientation (211). It was found that the Sb₂Se₃ thin films with the orientation (211) were suitable for an absorber layer of solar cells, due to their anisotropic properties.

Sun tracking systems are often used to improve the performance of crystalline silicon photovoltaic plants. However, their power consumption still remains a challenge till date. In this paper, a low power consumption sun tracking system has been implemented for driving a crystalline silicon photovoltaic module under variable weather conditions. The experimental results showed that this sun follower consumes less than 1% of the increased energy. Taking into account the tracker consumption, the energy gain can attain up to 25% under the same weather conditions compared to a fixed photovoltaic system. In addition to that, results gotten from data-based simulations are coherent with experimental results.

Parabolic trough collectors (PTC) are solar thermal energy collectors designed to capture the sun’s direct radiation over aperture area and concentrate it onto a focal point. Parabolic shaped mirrors are used to focus the solar radiation on the pipe that carries water to heat it. The concentrated heat from the parabolic collector heats up the water and helps in producing hot water which can be used domestically. Drying is one of the important and energy consuming processes. Especially foragricultural product processing open yard drying is widely adapted, without proper hygienic condition. The presently designed cost effective two in one PTC setupcanheat water and air simultaneously. In the box shaped structure the hot water isgenerated at the top of the box. The unused absorbed heat on the collector is used to heat the air which is passed via bottom chambers. As a result, hot water (60°C) and hot air (45°C) can be obtained which is used mainly for heating purpose. Manual tracking type of design is chosen for cost effectiveness and simplicity in structure. This Combined water and air heating design improves the total efficiency of the system up to 4.3% when compared with the conventional PTC design. In addition, the emission reduction of 1 kg of CO₂/day can be achieved and simple payback period is 2 years when compared to electric heaters which can be easily affordable by common man.

The analysis of solar energy conversion methods in the projects of solar power satellites (SPS) has been conducted and the problems restraining their implementation analysed. Therefore, the article provides grounds for using promising heat-resistant materials of carbonic nanocomposite and low-temperature superconductors in the scheme of solar energy conversion with the purpose of creating SPS projects of a new type with improved weight and size parameters and physical and technical characteristics. The difference between the gyroscopic solar power satellites (GSPSs) with the new thermal conversion system (TCS) and superconductive generator projects and the previous ones lies in the absence of steam and gas turbine plants, a thermal radiator and a system of direction to the sun. The results of assessment of their energy and weight and size parameters have been presented: the thermal efficiency of conversion by the helium as working fluid at concentration of the solar energy of 74 and by the water steam at 38 has made 85% and 62.7% respectively; the specific weight of the entire thermal conversion system has made 2.17 kg/kW and 2.61 kg/kW; its specific capacity – 12.3 and 6.79 kW/m², the specific weight of the GSPS with the new TCS and superconductive generator has made 0.46 and 0.38 kW/kg. The suggested principle of functioning may be used in space power plants, being based on planets and the Moon.

This article examines the possibility of improving the energy efficiency of small advanced hydropower plants planned for construction on the operated multipurpose water–power tract in the Samarkand region. The variability of changes in the capacity generated monthly during the year and in the amounts of electricity generated by such small-scale hydropower plants (HPPs) as the Shaudar and Bagishamal power plants of the water-and-power path is numerically analyzed and found out to be 7.2 and 6.0 MW, respectively. A significant difference in the energy performance of the hydropower plants is discovered in their developed capacity and amount of electricity generated in winter–spring, summer, and autumn–winter. To equalize the fluctuations in the developed capacity produced by small hydropower plants, the expediency of using the energy of mountain-valley winds of the surface (up to 60–70 m) layers of the atmosphere in the zone of the water–power path is justified, including the possibility of creating integrated hydropower and wind power plants. This is based on a joint analysis of the regimes of watercourses and wind flows, which showed their complementarity during their minima and maxima. Numerical studies have allowed estimating the average monthly amount of electricity generated by 60, 250, 500, and 750 kW windmills of different types when installed at different heights above the Earth’s surface; the average daily runtime by months, the average monthly runtime duration and continuous downtime. The data from the numerical studies of the operation of the windmills have allowed justifying the expediency of creating energy–generation systems with mutually complementary operation modes of HPPs and WPPs with different variants of using windmills of particular capacity at different altitudes. The necessary area of the territory for placing windmills to create WPPs with a capacity commensurate with the capacity of advanced small hydropower plants is estimated.

The article is a study of the situation on the global solar energy market and the features of designing and planning power plants based on variable renewable energy, and provides a SWOT analysis and conditions for including renewable energy into the fuel and energy balance of the republic, and also factors affecting the widespread adoption of renewable energy technologies. In addition, the scenario and model of developing renewable energy in Uzbekistan are suggested.