Applied Solar Energy最新文献

The integration of solar photovoltaic (PV) systems with thermoelectric generator (TEG) and composite phase change material (CPCM) represents a transformative approach to overcoming the inefficiencies associated with standalone solar technologies. This review critically analyzes recent advances in hybrid SPV-TEG-CPCM systems, focusing on material innovations, system configurations, and their collective impact on energy efficiency and thermal regulation. The novelty of this integration lies in its ability to harness waste heat from SPV modules and utilize it for secondary power generation and thermal storage, thus improving energy conversion rates and ensuring operational stability under fluctuating environmental conditions. The paper synthesizes state-of-the-art research, highlights technical challenges, and outlines future research directions, offering a structured and in-depth perspective for researchers and engineers.

Solar stills are simple and environmentally friendly devices for small-scale freshwater production, but their productivity and energy efficiency are often limited. This study aims to evaluate the combined influence of internal reflectors and aluminum oxide (Al₂O₃) nanofluid on the energy, exergy and economic performance of a single-slope solar still. A transient numerical model is developed for a conventional single-slope solar still and three modified configurations: with Al₂O₃ nanofluid, with internal reflectors, and with both modifications. The model solves the coupled energy balance equations for the basin liner, saline water and glass cover, and incorporates standard correlations for convective, evaporative and radiative heat transfer. Nanofluid properties are evaluated for an Al₂O₃. Exergy transfer and exergy destruction are calculated for each component. Simulations are carried out for a typical day in March under Dhahran climatic conditions, and the model is validated against published experimental data. The combined configuration with internal reflectors and Al₂O₃ nanofluid achieves the highest daily water productivity (4.258 L/m² day) and daily energy efficiency (52.3%), compared with 2.758 L/m² day and 33.9% for the conventional still. The basin liner is identified as the dominant site of exergy destruction. A preliminary economic assessment indicates shorter payback time for the enhanced configurations. Internal reflectors provide the largest performance gains by increasing incident solar energy, while Al₂O₃ nanofluid offers additional improvement by enhancing internal heat transfer. Their combination yields the best overall energy, exergy and economic performance, and highlights the importance of integrated optical and thermal enhancements in solar still design.

For the synthesis of precursors and ceramics with the nominal composition Bi_1.7Pb_0.3Sr₂Ca₂₉Cu₃₀Oᵧ, the solar gradient melt alloy quenching technology was employed. The obtained precursors and ceramics expel a magnet along the direction of the external magnetic field. This expulsion effect is also observed under the action of a directed light flux. Scanning electron microscopy (SEM) revealed a layered morphology of the precursors and ceramics, featuring caverns formed within the volume of the plate-like layers. Submicron-sized particles are located inside these caverns. X-ray diffraction (XRD) analysis confirmed the existence of superconducting homologous phases differing in stoichiometry. Such a structure can be interpreted as quasi-heterophase. Electrical resistance and magnetic properties were investigated in the temperature range of 79–460 K under ambient air conditions. Anomalous changes in resistance and magnetic induction were detected at temperatures of 280, 320, and 420 K. Ceramics are subject to thermal treatment for 1–3 h exhibit behavior characteristic of semiconductors, namely a decrease in resistance with increasing temperature. However, after thermal treatment exceeding 24 h, a transition to a superconducting-type dependence is observed. Samples that were not subject to annealing (i.e., retaining defects formed during melt quenching) demonstrate transitions at temperatures above 200 K. An explanation for the formation of high-temperature superconductivity (HTSC) is proposed based on the formation of a system of homologous phases constituting a quasi-heterophase system.

Thermal energy storage (TES) systems have become advanced technologies for storing and releasing thermal energy during periods of imbalance between energy generation from renewable energy sources and consumption. Phase change materials (PCM) have the capability to store significant amount of thermal energy through latent heat absorption and release. However, thermal energy storage (TES) systems should be designed to accelerate the melting process of the phase change materials. In this study, the influences different fin designs (annular shaped, longitudinal shaped, extruded shaped) on the heat transfer process and phase transition characteristics of a PCM in Latent heat thermal energy storage (LHTES) systems are numerically investigated using finite element method (FEM). Additionally, only charging process was considered in this comparative analysis. Through the thermal assessment, it was found that Model 4 LHTES with extruded fin demonstrated more uniform temperature distribution and faster phase transition during 6-h time interval when compared to other designs of fins. The complete melting of PCM within the Model 4 LHTES with extruded fin was observed at around 3 h and 20 min, whereas the PCM in Model 3 LHTES with longitudinal fins fully transitioned to the liquid at the 3 h and 42 min. In contrast, the PCM in the Model 2 LHTES with annular fins had entirely melted at 4 h, the melting process on Model 1 LHTES without fins was still continue during 6 h period. These numerical results facilitate a more comprehensive understanding of key aspects of fins integration to optimizing future LHTES system design.

This study aims to evaluate a solar chimney-based natural ventilation evaporative cooling (NVEC) system in pig housing environments as a low-cost and sustainable solar energy solution for cooling pig housing environments across growth stages. The system was tested in four pig growth stages: weaning, nursery, growing, and finishing. The results showed that solar energy-driven chimney ventilation can maintain a desirable thermal environment for pigs at weaning, nursery, and growing stages, but cannot for pigs at the finishing stage, as they require a much cooler environment. There is a significantly strong positive correlation (r = 0.96, p < 0.05) between solar chimney temperature and ventilation rate, highlighting the significance of solar thermal energy in the solar chimney to initiate and facilitate airflow, and passively remove heat from the pig house environment. Solar chimney ventilation had a 37% energy-saving efficiency compared to traditional ventilation, which could improve pig farmers’ economic viability. The solar chimney ventilation system is limited to pig barns and applies to different livestock facilities. This study not only promotes the integration of solar thermal energy into regulating thermal environment in livestock facilities, but also promotes efficient energy use, environmentally friendly initiatives and sustainability in livestock farming.

This study systematically investigates the role of thiourea (TU) as an additive in optimizing the performance of (FAPbI₃)_0.85(MAPbBr₃)_0.15 perovskite solar cells (PSCs). Using controlled fabrication in an inert glove-box environment, we examined how varying TU concentrations (0–0.15 mM) influences film morphology, crystallinity, and photovoltaic performance. More specifically, X-ray diffraction (XRD), UV-Vis and photoluminescence (PL) spectroscopy, and scanning electron microscopy (SEM) measurements revealed that 0.1 mM TU significantly enhances film quality, producing larger, more uniform grains (∼2 μm) with improved crystallographic orientation along the (001) and (002) planes with less pinholes. The champion solar cell devices achieved a PCE of 19% with Voc = 1.11 V, Jsc = 23.5 mA/cm², and FF = 73%, representing a significant improvement over the control device (PCE of 15.5%). These findings offer practical guidelines for the application of morphology-advancing additives in perovskite photovoltaics and contribute to the development of more efficient and stable solar energy conversion devices.

Hydrogen, when produced from renewable energy sources (RES), emerges as a highly desirable and sustainable fuel, offering a pathway toward decarbonizing energy systems. Among the various methods of green hydrogen generation, water electrolysis powered by renewable energy stands out as the most environmentally benign approach. This study presents experimental findings and software modeling developed in MATLAB for a small-scale solar hydrogen generation system utilizing proton exchange membrane (PEM) electrolysis. The experiments were conducted in the Ouargla region of southeastern Algeria, characterized by its arid desert climate, to evaluate the system’s performance under real-world conditions. The system integrates two NM 54 polycrystalline photovoltaic (PV) panels, each with a capacity of 250 W, a power control unit equipped with DC-DC converters, and a PEM electrolyzer. Key experimental results revealed that the system produced approximately 295 dm³ of hydrogen during the trial period. These findings provide a foundational benchmark for scaling up and optimizing hydrogen production systems capable of year-round operation in similar climatic conditions. In addition to the technical analysis, an economic assessment was conducted to estimate the levelized cost of hydrogen (LCoH). Sensitivity analysis highlighted the significant influence of the electrolyzer’s capital cost on the LCoH. The projected results indicate that the cost of producing hydrogen from solar energy in Ouargla is economically competitive, with an estimated LCoH of $8.8 per kilogram of hydrogen. This study underscores the feasibility of solar-driven hydrogen production in desert regions and contributes valuable insights for advancing renewable hydrogen technologies in resource-abundant areas.

This work reports the formulation and performance assessment of composite phase change materials (C-PCMs) for solar thermal energy storage, comprising stearic acid (SA), recycled aluminum (Al) powder (5–25 wt %), and sodium dodecyl sulfate (SDS, 0–2.5 wt %). The approach addresses SA’s low thermal conductivity and dispersion instability. Optimal performance was achieved with 15 wt % Al and 1.5 wt % SDS, yielding a 29% reduction in heating time and 43% increase in discharge duration (T > 45°C) relative to pure SA. SDS minimized sedimentation, improved UV–Visible absorption, and enhanced collector efficiency to 54.5%. However, additives reduced latent heat by 32.9%. Characterization via FTIR, DSC, TGA, and UV–Vis confirmed physical interactions, improved stability, homogeneity, and photothermal properties. Using recycled Al promotes sustainability and cost-effectiveness. These C-PCMs offer a viable solution for efficient solar water heating, balancing enhanced heat transfer and optical properties against latent heat trade-offs.

Standalone Photovoltaic systems (PV) with battery storage are considered to be the economical and environmentally beneficial option as an alternative to conventional electricity. In this research, detailed technical, and economic comparison of PV systems with different batteries have been considered. Lead Acid Batteries, and Lithium-ion batteries are considered as an energy storage medium. In technical analysis, the capacity requirement for both cases have been examined by considering the daily energy demand for a residential building in Karachi, Pakistan. The technical analysis also includes the battery capacity and mass requirement. Further, the energy payback has been thoroughly studied to explore the overall impact of the system on the environment. The PV system with Lead Acid Batteries achieves an energy payback of 5 years and save around 50 tons of CO₂ production over the lifespan of 20 years. On the other hand, PV system with Lithium-ion significantly longer energy payback of 17.5 years and just save around 10 tons of CO₂ production. To assess the performance of both systems in real time scenario, simulation through PVsyst has been conducted. The economic aspects are also compared by determining the Net Present Value (NPV), Life Cycle Cost (LCC), Levelized Cost of Electricity (LCOE), Life time Benefit (LTB), and simple payback and from overall analysis, PV with Lead Acid Batteries, with LCOE of $0.041/kWh was proved to be more economically beneficial as the other one using Lithium-ion batteries, $0.07/kWh as energy storage.

Use of glass facades is increasing day by day in modern buildings in order to improve the daylight availability and aesthetic views of the building. Lighting load of the building is directly influenced due to daylight through the glass window of the building. Controlling artificial lighting system according to available daylight into the building space reduce energy consumption of the building. However penetration of daylight into the building space increases heat gain which results higher cooling load in most of the places in hot and worm climatic zones in India. External shadings devices are useful means to control heat gain inside the building space and reduces cooling as well as lighting load of the building. The present study focuses on the effect of daylight integration into the building modelled according to National Building Code 2016 (NBC) and Energy Conservation in Building Code 2017 (ECBC 2017) in India through window combinations. Three different daylight conditions and five different windows to wall ratio (WWR) have been studied in Kolkata, India and the result is validated with two other locations situated in higher and lower latitude compared to study location to verify the applicability of the result to other places. The result is compared to a reference building to quantify the benefits of daylight integration with artificial lighting system in terms of long term energy savings and economic benefit.