Applied Solar Energy最新文献

This research focuses on conducting computer simulations of aerodynamic processes to study the behavior of airflow and dust deposition near a solar photovoltaic panel installed on a horizontal ground surface using COMSOL Multiphysics software. The Spalart–Allmaras (SA) turbulence model was used to simulate the air flow, and a Lagrangian approach was used to model particle motion. This paper analyzes the influence of wind speed and dust particle size on the level of dust deposition on the surface of a photovoltaic panel, with wind attack angles from 0° to 180° and wind speeds from 2 to 12 m/s. The results show that changing the wind attack angle affects the dust deposition rate, and increasing the wind speed reduces this rate. At wind speeds above 2 m/s (at any angle of attack), an increase in dust particle diameter or material density increases the dust deposition rate. The maximum dust deposition rate of 15.8% is observed at a wind attack angle of 0° with a wind speed of 2 m/s for a particle diameter of 200 µm. The results of the numerical simulation of dust deposition near and on the surface of PV panels can be used to more accurately predict performance losses under actual operating conditions of existing or planned PV systems in regions with high airborne dust levels, which allows optimizing panel cleaning schedules. This is especially important for regions with a high frequency of dust storms, where dust accumulation significantly reduces the efficiency of solar panels. Predicting dust accumulation and the corresponding drop in output power helps to plan maintenance in a timely manner and minimize generation losses, thereby reducing operating costs and extending equipment service life. Preventing a significant efficiency drop due to dust deposition contributes to more sustainable development of solar energy, reducing the need for additional capacity and minimizing the environmental footprint of producing and installing additional panels.

The study summarizes the research conducted worldwide on the design and implementation of hybrid energy systems combining wind and solar energy to generate reliable and sustainable electricity. In general, wind and solar energy sources are used independently to generate electricity. However, it is clear that generating electricity by combining different renewable energy sources, called Hybrid Power System (HPS), will increase the system efficiency and provide a greater balance in energy supply. The use of hybrid renewable energy systems (HRES) for electricity generation is emerging as a better, more effective, higher efficiency solution than traditional energy sources and in this context can be considered as a system choice with high potential to contribute to the sustainable development goals (SDGs), low-carbon society and efficient use of energy globally in the near future. HRESs, consisting of combined solar and wind energy systems, are attractive and suitable for various applications and are most commonly used for electricity generation in rural and urban areas.

This study focuses on the design, development, and analysis of an indirect solar food drying system tailored to the climatic conditions of Meknes, Morocco. The system aims to effectively reduce the moisture content of various products and consists of two main components: a solar air collector (SAC) and a drying cabinet. Computational Fluid Dynamics (CFD) was used to analyze airflow distribution and thermal characteristics within the dryer. Temperature measurements taken in July showed peak temperatures of 64.8 and 57.6°C at the SAC outlet, and 57.4 and 51.4°C at the drying chamber outlet on the first and second days, respectively. The comparison between numerical and experimental data yielded a maximum percentage difference of 1.25%. The temperature contours revealed higher temperatures at the chamber inlet, particularly near the floor. The average outlet temperature and air velocity were 43.8°C and 1.48 m/s, respectively, with a consistent temperature profile as air passed through the trays. The pressure distribution within the chamber was uniform. Temperature values at the dryer outlet increase by decreasing air flow rate, with 51.8°C recorded at the lowest mass flow rate of 0.0109 kg/s. Finally, the drying kinetics of banana slices were best described by the Page model, with an effective moisture diffusivity of 3.06 × 10^–10 m²/s.

This study presents a scalable methodology for assessing rooftop solar photovoltaic (PV) potential in Central Asia, utilizing open-source geospatial data from OpenStreetMap (OSM) and PVGIS, and integrating the Minimum Rotated Rectangle (MRR) method for rooftop orientation analysis. Applied to Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan, the approach estimates installable capacity, annual energy yield, and economic viability through metrics such as Levelized Cost of Electricity (LCOE), Net Present Value (NPV), and Payback period (PP). Results indicate significant technical potential, with Kazakhstan leading at 61.43 GW and 49.00 TWh/year, followed by Uzbekistan at 35.07 GW and 32.28 TWh/year. Smaller nations like Kyrgyzstan (12.32 GW, 10.67 TWh) and Tajikistan (9.92 GW, 8.68 TWh) show substantial per-capita potential, while Turkmenistan benefits from the highest specific yield (1584.89 kWh/kW). LCOE ranges from 0.0273 USD/kWh (Turkmenistan) to 0.0378 USD/kWh (Kazakhstan), but economic feasibility varies due to tariff structures, with Kazakhstan and Uzbekistan approaching unsubsidized viability, while Kyrgyzstan and Turkmenistan require significant subsidies (453.17 USD/kW and 1622.22 USD/kW, respectively). Validated against operational PV systems in Dushanbe (±10% deviation from PVGIS benchmarks), the methodology demonstrates reliability for data-scarce regions. By providing geospatial outputs, this study supports energy planning and policy formulation, contributing to SDG 7 (Affordable and Clean Energy) and offering a transferable framework for developing regions with limited geospatial data.

Solar energy, with its vast availability and sustainability, offers diverse applications such as electricity generation, water heating, vehicle power, and support for industrial activities. However, solar energy adoption rates vary across countries due to factors such as geographical location, solar resources, policy frameworks, energy infrastructure, and market conditions. Meanwhile, freshwater scarcity is becoming a global concern. Solar water desalination, a sustainable technology utilizing solar energy to remove salt from seawater and presents a potential solution. This review paper comprehensively assesses various solar water desalination methods, primarily focusing on energy conversion efficiencies and associated costs. Solar stills, though simple and affordable, demonstrate relatively low efficiencies ranging from 30 to 50%, making them suitable for small-scale or remote applications. Conversely, solar-powered Reverse Osmosis (RO) systems exhibit lower efficiencies of approximately 6 to 10% but come with variable costs ranging from $0.5 to $4 per cubic meter (m³). Solar-powered Multi-Effect Distillation (MED) and Multi-Stage Flash (MSF) systems boast higher thermal efficiencies, ranging from 30 to 70% and 30 to 50%, respectively, but may entail higher initial investment costs. This study highlights the trade-offs between efficiency and cost, offering valuable insights for decision-makers and stakeholders in implementing solar water desalination projects.

We presented scientific, methodological, and engineering approaches to the application of energy-active window units in the construction of passive houses, taking into account the climatic conditions of the Republic of Uzbekistan’s regions, which significantly enhance the energy efficiency of buildings. We examined international regulations governing the use of passive strategies and based on these, proposed boundary conditions for the parameters and indicators of energy-active window units to ensure their compliance with current standards. A critical analysis of the designs of energy-active window units was conducted, with a proposed classification based on functional purpose, frame material, construction type, tranclucent-filler type, number and arrangement of sealing contours, as well as sash design solutions and operational characteristics. We also evaluated the maximum and minimum outdoor temperatures by month for the period from 2000 to 2023 and developed temperature distribution maps across the regions of the republic. These maps serve as a basis for analyzing seasonal fluctuations and for developing window systems that provide effective insulation and reduce heat loss during cold periods. In light of the increasing number of days with extremely high temperatures, an analysis of data on the average number of hours with temperatures above 35°C was conducted. This provides a comprehensive understanding of the temperature conditions affecting the thermal load on buildings in the republic and serves as a foundation for developing effective energy-saving solutions. A new design of energy-active window units with a triple-glazed transparent enclosure and a heat transfer coefficient reduced to 0.5 W/(m² K) is proposed, which improves thermal efficiency by 30–50%, utilizing an air layer and L-shaped brackets to simplify operation and enhance insulation properties and efficiency in various climatic conditions.

The architecture of perovskite solar cells (PSCs) and the interfaces between charge transport layers and the perovskite layer are crucial to performance. These layers impact the morphology of the perovskite layer and the processes of charge extraction and recombination. This study investigates performance enhancement in PSCs by incorporating PEDOT: PSS and PTAA as hole transport layer (HTL). Various surface treatments were used to improve PTAA’s wettability, significantly enhancing layer adhesion and overall cell efficiency. Our findings suggest that optimizing HTLs and surface treatments can lead to more efficient and stable PSCs.

Optimizing the air gap between the absorber and the glass cover is a critical factor in designing solar air heaters. This study aims to analyze the effect of gap variation on a double pass solar air heater’s (DPSAH) performance through four distances 3, 6, 9 and 12 cm, using experimental data and numerical analysis via CFD (ANSYS Fluent). The numerical model was validated with experimental results in good agreement. The findings indicate that increasing the height of the upper channel correlates with the enlargement of a vortex, intensifying conduction over convection mode at the onset of this channel, and reducing heat loss by eliminating the stagnation vortex in the lower corner, the maximum local heat transfer coefficient was observed at the lower channel by 14.61 W/m² K. The thermal efficiency reached 66.4% in 12 cm, dropping by 2.4, 7.8 and 14.4% for 9, 6 and 3 cm configurations, respectively. Similar to the exergy efficiency, which ranges between 2.1 and 2.6%. Furthermore, the optimum configuration (12 cm) was tested to a variable mass flow rate of 0.006, 0.012, and 0.015 kg/s, with the highest rate yielding a thermal efficiency of 72.5%.

The primary challenge in renewable energy production is the unpredictable nature of renewable sources, leading to inconsistent electricity generation. This variability causes deviations in power supply frequency and voltage due to imbalances between load demand and power generation. This study focuses on regulating power flow in a solar-wind-based Hybrid Power Generating System (HPGS) to achieve a stable balance between energy generation and demand. A Fractional Order PID (FOPID) controller is employed to minimize power fluctuations by ensuring Maximum Power Point Tracking (MPPT) and efficient management of Superconducting Magnetic Energy Storage (SMES). The SMES utilizes a second-generation superconducting material with a high irreversibility field and critical current density, enhancing energy storage efficiency. Compared to a conventional PID controller, the FOPID controller offers greater stability, reduced oscillations and overshoot, and a shorter rise time. To validate its effectiveness, a comparative analysis between conventional PID and FOPID controllers is conducted. The results demonstrate that the proposed FOPID controller ensures precise MPPT, rapid SMES response, and stable power exchange between supply and demand, even during sudden load shifts and variations in power generation.

This study presents the geometric optimization of a CeO₂-based solar thermochemical reactor intended for hydrogen production, using temperature distribution analysis under concentrated solar power conditions. The investigation was carried out entirely through numerical modeling using the COMSOL Multiphysics software, assuming a concentrator input power of 2 kW. The reactor body was designed with a stainless-steel exterior, while aluminum oxide (Al₂O₃) was selected as the internal insulating layer. Cerium oxide (CeO₂) was employed as a porous reactive medium to facilitate a two-step redox thermochemical cycle. A three-dimensional cylindrical model of 1 mol CeO₂ was developed to evaluate the thermal performance under varying porosity levels (ε = 0.1–0.9) and different cylindrical geometries with equal volumes. The simulation results revealed that at a porosity of ε = 0.7, the desired endothermic operating temperature was distributed most uniformly within a CeO₂ volume of 50 mm diameter and 20 mm thickness. Based on the temperature field distributions and effective heat transfer conditions, the reactor’s geometrical parameters were optimized. The final design includes a cylindrical body with a 220 mm diameter and 140 mm length, a quartz window of 200 mm diameter and 6 mm thickness, a 20 mm cooling channel for water circulation, and an internal insulating layer of aluminum oxide (Al₂O₃) with a thickness of 100–120 mm. Furthermore, the dimensions of the light-receiving conical section were determined as 50 mm for the small diameter and 152 mm for the large diameter.