The wide bandgap Sb2S3 is considered to be one of the most promising absorber layers in single‐junction solar cells and a suitable top‐cell candidate for multi‐junction (tandem) solar cells. However, ...compared to mature thin‐film technologies, Sb2S3 based thin‐film solar cells are still lagging behind in the power conversion efficiency race, and the highest of just 7.5% has been achieved to date in a sensitized single‐junction structure. Furthermore, to break single junction solar cell based Shockley–Queisser (S–Q) limits, tandem devices with wide bandgap top‐cells and low bandgap bottom‐cells hold a high potential for efficient light conversion. Though matured and desirable bottom‐cell candidates like silicon (Si) are available, the corresponding mature wide bandgap top‐cell candidates are still lacking. Hence, a literature review based on Sb2S3 solar cells is urgently warranted. In this review, the progress and present status of Sb2S3 solar cells are summarized. An emphasis is placed mainly on the improvement of absorber quality and device performance. Moreover, the low‐performance causes and possible overcoming mechanisms are also explained. Last but not least, the potential and feasibility of Sb2S3 in tandem devices are vividly discussed. In the end, several strategies and perspectives for future research are outlined.
This review summarizes the progress that has been reported to date for low‐cost, non‐toxic, and wide‐bandgap Sb2S3 thin film solar cells. The significant breakthroughs achieved in improving the absorber quality and device performance have been comprehensively collected and analyzed. The critical challenges, possible strategies, high potential as a top‐cell candidate in tandem devices, and future perspectives are vividly discussed.
The conventional environment polluting energy sources and the continuous growing energy demand compelled researchers to find alternative energy sources. Therefore, in recent years, extensive research ...has been carried out in synthesizing catalysts for energy conversion applications. This review focuses on the application of various electrodeposition methods in the synthesis of energy‐related electrocatalyst and briefly discusses different electrocatalyst characterization techniques. Further, the influence of various parameters on the electrocatalyst activity and stability is highlighted. Electrocatalyst application in clean energy conversion reactions, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction, nitrogen reduction reaction along with the metal‐air/CO2 battery, are reviewed. Finally, the comparative experimental data are provided as a reference to synthesize the next‐generation electrodeposited electrocatalyst in clean energy conversions and beyond.
The synthesis of highly active and stable electrocatalysts for efficient energy conversion is important for a sustainable environment. Herein, the pioneering recent progress in applying simple and facile electrodeposition methods for the synthesis of electrocatalysts for energy conversion reactions is presented. The effect of various parameters such as electrolytes, concentration, and deposition time on electrocatalyst performance is discussed.
With the excessive energy consumption worldwide, the demand for saving strategies increases. Energy consumption in public buildings increased drastically over the last decade. Significant policy ...actions towards the promotion of energy-efficiency in the building sector have been developed with different intensity and structure. This study aims at proposing a retrofit strategy in an attempt to improve energy efficiency in a sample of higher educational buildings located in a hot arid climate (Egypt). Retrofitting some of the building’s envelope features can provide comfort without compromising functional needs. Comfort needs, which include thermal, visual and acoustical, can reduce energy consumption. Emphasis is placed on thermal comfort in terms of energy efficiency. Some of the important measures used in the retrofitting process of the building envelope include: external walls’ insulation, windows’ glazing type, air tightness (infiltration) and solar shading. The study results show that simple retrofit strategies such as solar shading, window glazing, air tightness then insulation can reduce energy consumption of an average of 33%. From the feasible envelope features’ used in this study, the research provides a suggestion for design codes that maintains thermal comfort, propose a feasible strategy for retrofitting and a baseline reference specifically devised for local energy efficiency.
The performance of a solar photovoltaic (PV) panel is examined through determining its internal parameters based on single and double diode models. The environmental conditions such as temperature ...and the level of radiation also influence the output characteristics of solar panel. In this research work, the parameters of solar PV panel are identified for the first time, as far as the authors know, using hybrid particle swarm optimization (PSO) and grey wolf optimizer (WGO) based on experimental datasets of I-V curves. The main advantage of hybrid PSOGWO is combining the exploitation ability of the PSO with the exploration ability of the GWO. During the optimization process, the main target is minimizing the root mean square error (RMSE) between the original experimental data and the estimated data. Three different solar PV modules are considered to prove the superiority of the proposed strategy. Three different solar PV panels are used during the evaluation of the proposed strategy. A comparison of PSOGWO with other state-of-the-art methods is made. The obtained results confirmed that the least RMSE values are achieved using PSOGWO for all case studies compared with PSO and GWO optimizers. Almost a perfect agreement between the estimated data and experimental data set is achieved by PSOGWO. KEYWORDS Modern Optimization, Parameter Estimation, Renewable Energy, Energy Efficiency, Single-diode Model, Double-diode Model.
Dairy and plant-based proteins are widely utilized in various food applications. Several techniques have been employed to improve the techno-functional properties of these proteins. Among them, ...pulsed electric field (PEF) technology has recently attracted considerable attention as a green technology to enhance the functional properties of food proteins. In this review, we briefly explain the fundamentals of PEF devices, their components, and pulse generation and discuss the impacts of PEF treatment on the structure of dairy and plant proteins. In addition, we cover the PEF-induced changes in the techno-functional properties of proteins (including solubility, gelling, emulsifying, and foaming properties). In this work, we also discuss the main challenges and the possible future trends of PEF applications in the food proteins industry. PEF treatments at high strengths could change the structure of proteins. The PEF treatment conditions markedly affect the treatment results with respect to proteins' structure and techno-functional properties. Moreover, increasing the electric field strength could enhance the emulsifying properties of proteins and protein-polysaccharide complexes. However, more research and academia-industry collaboration are recommended to build highly effective PEF devices with controlled processing conditions.
This study scrutinizes the reliability and validity of existing analyses that focus on the impact of various environmental factors on a photovoltaic (PV) system’s performance. For the first time, ...four environmental factors (the accumulation of dust, water droplets, birds’ droppings, and partial shading conditions) affecting system performance are investigated, simultaneously, in one study. The results obtained from this investigation demonstrate that the accumulation of dust, shading, and bird fouling has a significant effect on PV current and voltage, and consequently, the harvested PV energy. ‘Shading’ had the strongest influence on the efficiency of the PV modules. It was found that increasing the area of shading on a PV module surface by a quarter, half, and three quarters resulted in a power reduction of 33.7%, 45.1%, and 92.6%, respectively. However, results pertaining to the impact of water droplets on the PV panel had an inverse effect, decreasing the temperature of the PV panel, which led to an increase in the potential difference and improved the power output by at least 5.6%. Moreover, dust accumulation reduced the power output by 8.80% and the efficiency by 11.86%, while birds fouling the PV module surface was found to reduce the PV system performance by about 7.4%.
A novel statistical performance evaluation of most modern optimization-based global MPPT techniques for partially shaded PV system is presented in this paper. In recent years, there has been a ...growing attention toward mitigation of partial shading effect of the PV system through using modern optimization. The field of tracking MPP of the PV system attracts huge attention from the researchers, as it is the best way to increase PV plant efficiency. Under non-uniform solar irradiance, the power against voltage characteristics of PV array have more than one MPP. This condition leads to extra complications to track MPP and decreases the efficiency of the PV system. Traditional MPPT methods are typically used to increase the harvested energy of PV under normal conditions without any problems. The key drawback of such methods is failing extraction of global MPP under actual weather conditions that sometimes under shadowing condition. Several global MPPT methods based on modern optimization are presented for extracting global MPP in case of shadowing condition. The essential target of this work is not limited to present an integrated specific review on the state-of-the-art of these techniques; but also a comprehensive statistical evaluation of twenty optimizers that represent high percent of all the reported techniques is performed with changing shading scenarios. This work serves as a source of valuable information for researchers and engineers working with PV systems to keep abreast with the modern advance in the field of tracking MPP of PV system.
•An integrated specific review on the state-of-the-art of different global MPPT techniques is done.•A comprehensive statistical evaluation of twenty optimizers is performed.•Teaching-learning-based optimization and grey wolf optimizer are performed the best.•This work serves as a source of valuable information for researchers working in solar energy sector.
Thermoelectric generation technology is considered to be one of the viable methods to convert waste heat energy directly into electricity. The utilization of this technology has been impeded due to ...low energy conversion efficiency. This paper aims to improve the energy conversion efficiency of the thermoelectric generator (TEG) model with a novel maximum power point tracking (MPPT) technique. A variable fractional order fuzzy logic controller (VFOFLC)-based MPPT technique is proposed in the present work in which the operating point of the TEG is moved quickly towards an optimal position to increase the energy harvesting. The fraction order term α, introduced in the MPPT algorithm, will expand or contract the input domain of the fuzzy logic controller (FLC to shorten the tracking time and maintain a steady-state output around the maximum power point (MPP). The performance of the proposed MPPT technique was verified with the TEG model by simulation using MATLAB /SIMULINK software. Then, the overall performance of the VFOFLC-based MPPT technique was analyzed and compared with Perturb and observe (P&O) and incremental resistance (INR)-based MPPT techniques. The obtained results confirm that the proposed MPPT technique can improve the energy conversion efficiency of the TEG by harvesting the maximum power within a shorter time and maintaining a steady-state output when compared to other techniques.
There is a growing demand to find an effective extraction process of sulfated polysaccharides from brown algae to conserve its structure and biological activity. Fucoidan was recovered from Sargassum ...sp. using a hot buffer extraction process. Box–Benhken experimental design was evaluated to study different conditions of temperature, pH and buffer: alga ratio on fucoidan yield and its sulfate content. By solving the regression equations and analyzing 3-D plots, the optimum conditions were at extraction temperature 60 °C, pH 4.0, and ratio of buffer: alga 10.0 mL/g. Under these conditions, the experimental fucoidan yield, and sulfate content were 19 and 47.6% (w/w), respectively, which were in good agreement with the predicted values. The use of hot buffer extraction was efficient to obtain a high fucoidan yield with maintaining high sulfate contents. Fucoidan preparations showed variations in antioxidant properties using various antioxidant assays. Increasing reducing antioxidant activity and hydroxyl radical scavenging of fucoidan extracts was attributed to increasing total sugars, fucose, and uronic acids. The data obtained suggested that the sulfate groups might act as reductones rather than radical scavengers to contribute to the antioxidant activity of fucoidan. Additionally, proteinaceous and phenolic compounds co-extracted with crude fucoidan contributed to its antioxidant potential. Crude fucoidan demonstrated good emulsion stabilizing capacities, especially with cedar wood oil and xylene. These results suggest the use of the crude fucoidan as a good alternative to many synthetic polymers, as well as other natural polysaccharides, in several applications in the food, pharmaceutical, cosmetic, textile, paper and petroleum industries.
Display omitted
•Hot buffer extraction enhanced fucoidan yield and its sulfate content.•Yield and sulfate content of fucoidan were optimized using Box–Behnken design.•At optimum conditions, yield, and sulfate content were 19 and 47.6%, respectively.•Chemical characteristics and antioxidant activity of fucoidan were elucidated.•Crude fucoidan showed good emulsifying activity.
► Two datasets of pedestrian–vehicle crashes were analyzed for two cities. ► Latent class with ordered probit and K-means with multinomial logit are used. ► A cluster regression approach is ...recommended to identify severity contributing factors. ► Heavy vehicle, dark lighting conditions, mixed land use, and major road increase the likelihood of a fatal accident. ► Crossing at intersections lowers the severity of an accident.
Understanding the underlying relationship between pedestrian injury severity outcomes and factors leading to more severe injuries is very important in addressing the problem of pedestrian safety. This research combines data mining and statistical regression methods to identify the main factors associated with the levels of pedestrian injury severity outcomes. This work relies on the analysis of two unique pedestrian injury severity datasets from New York City, US (2002–2006) and the City of Montreal, Canada (2003–2006). General injury severity models were estimated for each dataset and for sub-populations obtained through clustering analysis. This paper shows how the segmentation of the accident datasets helps to better understand the complex relationship between the injury severity outcomes and the contribution of geometric, built environment and socio-demographic factors. While using the same methodology for the two datasets, different techniques were tested. Within the New York dataset, a latent class with ordered probit method provides the best results. However, for Montreal, K-means with a multinomial logit model proves most appropriate. Among other results, it was found that pedestrian age, location type, driver age, vehicle type, driver alcohol involvement, lighting conditions, and several built environment characteristics influence the likelihood of fatal crashes. Finally, the research provides recommendations for policy makers, traffic engineers, and law enforcement in order to reduce the severity of pedestrian–vehicle collisions.
PDF
