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In recent years, the exploration of solar absorbers has grown in favor due to the scarcity of energy. Here, we propose an absorber with an array of a circular ring surrounding disk (RSD) for solar energy capture. The novel structure keeps above 93.5% absorption with an average absorption of 96.95% in wavelengths from 300 to 4000 nm. Meanwhile, the proposed absorber is advantageous in that the structure is generalizable to other metals and dielectric materials. Furthermore, the data results show that the absorber has polarization-independent properties as well as maintaining >90% absorption in the considered wavelength range up to an incidence angle of 52° and >95% absorption at large process tolerances. Finally, the excellent absorption under the AM1.5 solar spectrum demonstrates the RSD absorber's ability to capture solar energy. These results show the potential of the absorber for applications in electromagnetic invisibility cloaking, thermal emitters, and solar energy capture and conversion. [ABSTRACT FROM AUTHOR]

Photophysical, photovoltaic, and charge transport properties of fused core-modified expanded porphyrins containing two pyrroles, one dithienothiophene (DTT) unit, and 1–4 thiophenes (1–4) were inspected by using density functional theory (DFT) and time-dependent DFT. Compounds 1–3 have been investigated experimentally before, but 4 is a theoretical proposal whose photophysical features match those extrapolated from 1 to 3. They exhibit absorption in the range of 700–970 nm for their Q bands and 500–645 nm for their Soret bands. The rise of thiophene rings placed in front of the DTT unit in the expanded porphyrin ring causes a bathochromic shift of the longest absorption wavelength, leading to near-infrared absorptions, which represent 49% of the solar energy. All the systems show a thermodynamically favorable process for the electron injection from the dye to TiO2 and adsorption on a finite TiO2 model. The electron regeneration of the dye is only thermodynamically feasible for the smallest expanded porphyrins 1 and 2 when I−/I3− electrolyte is used. The charge transport study shows that for voltages lower than 0.4 V, junctions featuring pentaphyrin 1 and octaphyrin 4 are more conductive than those containing hexaphyrin 2 or heptaphyrin 3. The results showed that the four fused core-modified expanded porphyrins investigated are potential dyes for applications in dye-sensitized solar cells, mainly pentaphyrin 1 and hexaphyrin 2. Moreover, increasing the number of thiophene rings in the macrocycle proved fruitful in favoring absorption in the near-infrared region, which is highly desired for dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

Diffuse horizontal irradiance (DHI) forecasts are critical for adopting solar photovoltaic technology. Yet, they can lack reliability given the limited and uncertain meteorological data available for desert areas. This research develops a new sine cosine dipper throated optimization (SCDTO) technique, targeting DHI prediction even given such data constraints. SCDTO uniquely hybridizes sine cosine metaheuristics, adept at exploration, with dipper throat optimization, providing focused exploitation. This hybridization aims to create a robust ensemble model capable of delivering reliable DHI predictions despite climatic uncertainty. The ensemble model, employing various input combinations, was rigorously evaluated across multiple meteorological stations. The SCDTO algorithm exhibited remarkable performance improvements, yielding substantial reductions exceeding 93% in root mean squared error and 98% in mean absolute error at key stations in Morocco, including Tan-Tan, Zagora, Erfoud, and Oujda. Comparative analyses against established optimization algorithms consistently underscored the superior predictive capabilities of SCDTO. Visualizations, including box plots and histograms, demonstrated SCDTO's efficacy in minimizing prediction errors, particularly for Tan-Tan, Zagora, and Erfoud stations. Also, statistical validation through one-way analysis of variance (ANOVA) further affirmed the significance of the proposed SCDTO method. Therefore, this hybrid metaheuristic optimization enables more accurate DHI predictions from limited meteorological data. [ABSTRACT FROM AUTHOR]

Solar energy is an attractive alternative to fossil fuels (electricity and coke) for petroleum products generation. A solar-integrated binary chemical cracking of heavy oil system integrates solar energy into oil processing for carbon neutrality，in which pyrolysis and electrolysis benefit heavy oil conversion and hydrogen storage. This system has been studied in terms of solar chemical engineering, electrolyte engineering and electrode engineering. The results show improved hydrogen yield and cracking rate of heavy oil and a significant reduction in the operating temperature compared to catalytic cracking. The performance of molten salt electrolytes is as follows: binary NaOH–KOH > ternary KCl–LiCl + NaOH > ternary KCl–LiCl + NaHCO 3. In electrode engineering, the electro-catalytic electrodes are in an order of Inconel 718> Ni > Incoloy 825 electrodes in the cracking rate, Ni > Inconel 718>Incoloy 825 electrodes in the hydrogen yield, and Incoloy 825>Inconel 718>Ni electrodes in the ability, for sustainable and stable efficient production. [Display omitted] • Solar binary chemical cracking can efficiently upgrade fuel and abundantly generate hydrogen. • Solar binary energy is integrated into oil processing to replace fossil energy. • The starting reaction temperature is 230 °C, lower than the catalytic cracking. [ABSTRACT FROM AUTHOR]

Achieving highly efficient broadband absorption is an important research area in nanophotonics. In this paper, a novel method is proposed to design broadband near-perfect absorbers, consisting of a four-layer hemispherical concentric nanoshell array. The proposed nanostructure supports absorptivity exceeding 95% in the entire visible region, and the absorption bandwidth is determined by the interaction or 'hybridization' of the plasmons of the inner and outer metal-based nanoshells. Moreover, the designed absorber has wide-angle capability and is insensitive to polarization. The simple structure, as well as the stable absorption properties, suggests that such core–shell nanostructures can serve as a potential candidate for many applications such as solar energy harvesting, photo-detection, and emissivity control. [ABSTRACT FROM AUTHOR]

Shallow geothermal heat has the characteristics of wide distribution and huge reserves. However, for northern rural buildings, the heating load in winter is much greater than the cooling load in summer, and thermal imbalance of the soil is prone to occur. This paper takes rural residences in southern Hebei as an example and designs a solar-assisted shallow geothermal energy system. Compared with the original shallow ground-source heat pump system, the indoor and outdoor temperature differences of the target building were first analyzed. Second, the changes in the soil temperature field and the differences in the supply and return water temperature were monitored. Finally, the initial investment and operating costs of the assisted system are analyzed. The results show that the average ground temperature field increases significantly in winter. Through the alternate operation of solar energy and ground-source heat pumps, heat extraction from the ground is reduced, and the imbalance cycle of heat extraction in winter and heat removal in summer is shortened. It alleviates the imbalance of the cold and heat loads for soil throughout the year. The inlet and outlet water temperature and heat exchange efficiency of the buried pipes have been significantly improved. The energy efficiency ratio of the system using the assisted system has increased from 3.40 in 2020 to 4.17, an increase of 0.77. The optimal ratio of the solar- assisted shallow geothermal energy system is a 12.80 m2 solar heat-collection area and one buried hole. The winter heating operating cost of the solar-assisted shallow geothermal energy system is 18.86 CNY/m2. It can save 37% of the annual operating costs of heating, cooling, and hot water compared to a single ground-source heat pump system and 40%–45% compared to traditional heating and cooling modes. [ABSTRACT FROM AUTHOR]

In this demonstrated design, we built a perfect solar absorber, with three appropriate layers of base (tungsten) layer, substrate (aluminum), layer, and gold resonator in a cross-design. The absorption result of the demonstrated cross-design can be identified in three sections by dividing the whole wavelength range (2800 nm) into two sections the first 1400-nm bandwidth range (starting from 0.2 to 1.6 µm), and the second part of 1400 nm (between 1.6 and 3 µm) respectively. With the support of the adding graphene layer by developing the top and middle layer, the absorption percentage can be increased to 91% for the overall range of 0.2 and 3 µm. The developed cross-design absorption rate is above 90% at an overall bandwidth of 2800 nm. For the first half section of the 1400-nm bandwidth (0.2–1.6 µm), the absorption amount is observed more than 90%, and at the rest half of the overall wavelength (1.6–3 µm), the solar radiation is greater than 95%. To highlight the variation in absorption situations, the peak four wavelengths (micrometers) are picked up such as λ1 = 0.33, λ2 = 1.23, λ3 = 2.24, and λ4 = 2.6 respectively. In this developed cross-solar design, the absorber can be explored in the four spectra of ultraviolet (UV) region, violet (V), and near and middle infrared regions (NIR and MIR). The creation of the cross-design in many steps, and it can be also expressed with the AM 1.5 situation. To indicate the absorption value variations for this cross design, various parameter sections of the ground layer parameter, cross design length, and substrate length can be distinguished in four different peak wavelengths. The electric potential value changes and the color distinguished of the electric field progression of the cross-design can be also extinguished. Transverse electric value and magnetic (TE and TM) variations in four different peak wavelengths can be demonstrated by varying degrees from 0 to 50. Finally, the proposed cross-design absorption value can be compared with the other published design in a table with the respective sections of absorption percentage, bandwidth range, angle variation, and polarization sensitivity respectively. [ABSTRACT FROM AUTHOR]

The visible band is characterized by a high concentration of solar energy, making it highly desirable to achieve perfect absorption within this spectral range. This paper presents a novel design of a broadband metamaterial absorber (BMA) based on titanium (Ti), which exhibits a superior level of high absorption in the visible regime. The absorber is composed of three layers arranged from top to bottom: a newly shaped Ti top layer resonator, a SiO2 dielectric spacer, and a Ti bottom reflector. With a thickness of 195 nm, the BMA structure demonstrates an average absorption of 98.11% across the wavelength range of 400–800 nm, ensuring absorption levels greater than 90% through the entire visible band. The influence of different geometrical parameters and structures on absorption was studied, and the physical mechanism behind the high absorption was explored. Additionally, the proposed structure offers the benefit of maintaining 90% absorption stability for large incident angles up to 60° for TE and up to 70° for TM mode oblique incidence. Therefore, our proposed absorber emerges as an optimal candidate for a variety of solar energy harvesting applications. [ABSTRACT FROM AUTHOR]

Early in history, societies utilize renewable energy sources in response to technical developments and external factors, which resulted in the development of hydropower, wind turbines, and solar PV, as well as their support through policies and agreements. The double ring covered disk resonator solar absorber (DRCDRSA) structures are examined over the spectral range of wavelength 0.2 µm to 2.5 µm (UV-FIR) with the help of finite element method (FEM) in this study. This design achieved effective solar absorption, surpassing 99% over the 0.46 µm band, 95% over 2.05 µm wideband, and 90% over the entire observed spectral range, with an overall average absorbance of 96.38%. In addition, the maximum absorbance is 99.9% with three pick values at the wavelengths of 0.34 µm, 1.35 µm, and 1.51 µm. This research includes a parameter optimization as well as the electric field strength and magnetic field intensity distribution over a three-dimensional solar absorber construction. The structure's angle-polarization study shows it is polarization independent, handles diverse angles, and maintains even absorption up to 60° across all wavelengths. This study explores effective solar heaters for air and water systems, offering promising prospects for maximizing solar energy utilization. [ABSTRACT FROM AUTHOR]

Owing to the persisting hype in pushing toward global carbon neutrality, the study scope of atmospheric science is rapidly expanding. Among numerous trending topics, energy meteorology has been attracting the most attention hitherto. One essential skill of solar energy meteorologists is solar power curve modeling, which seeks to map irradiance and auxiliary weather variables to solar power, by statistical and/or physical means. In this regard, this tutorial review aims to deliver a complete overview of those fundamental scientific and engineering principles pertaining to the solar power curve. Solar power curves can be modeled in two primary ways, one of regression and the other of model chain. Both classes of modeling approaches, alongside their hybridization and probabilistic extensions, which allow accuracy improvement and uncertainty quantification, are scrutinized and contrasted thoroughly in this review. [ABSTRACT FROM AUTHOR]

Summary: In this work, the control of a Single‐Ended Primary‐Inductor Converter (SEPIC) supplied from a photovoltaic energy source and linked at its output to a DC current sink is addressed. The system is used for maximum power point tracking under varying environmental conditions. A strategy based on two loops of control is considered. A peak current mode controller is used for the inner loop, and a Proportional‐Integral (PI) controller is used for the outer voltage loop. Then, a comprehensive time‐domain and frequency‐domain modeling of the inner loop is theoretically addressed and then verified by the switched model of the system implemented in PSIM© software. The obtained results show that the system exhibits accurate tracking of the desired PV voltage while guaranteeing a fast maximum power point tracking under sudden changes in the environmental conditions. The mathematical modeling, design procedures, and the numerical simulations are validated using experimental results obtained from a laboratory prototype. [ABSTRACT FROM AUTHOR]

The current paper experimentally studied the performance of solar-driven internally cooled liquid desiccant system for hot and humid climates using CaCl2 as a liquid desiccant. The system is designed to investigate the input conditions of the room by adjusting various air and solution variables. This internally cooled liquid desiccant system consists of the dehumidifier and regenerator in a single module and the regeneration of the solution is done by solar energy. The present study analyzes the effect of solution concentration, air mass flow rate and solution volume flow rate using different performance indices such as humidity reduction, moisture effectiveness, enthalpy effectiveness, and COP. The results demonstrate that the maximum moisture reduction of 4.2 g/kg d.a. is found at an airflow rate of 0.03195 kg/s, a solution volume flow rate of 12.5 LPM, and a solution concentration of 37%, while the maximum COP of 0.274 is obtained at an airflow rate of 0.0715 kg/s, a solution volume flow rate of 12.5 LPM, and a solution concentration of 37%. The maximum moisture and enthalpy effectiveness are obtained as 24.1% and 26.2%, respectively. The paper also presents the correlations for moisture and enthalpy effectiveness based on findings from experiments. [ABSTRACT FROM AUTHOR]

Small islands in Indonesia usually have a million beauty and extraordinary natural wealth. However, the development of remote islands is prolonged due to the limited electricity supply on these islands. This limitation occurs because the island is far from the primary power grid or uses a diesel generator (DG). Using the DG will increase the cost of shipping fuel oil through limited sea transportation. Therefore, this study aims to conduct a feasibility study of a solar power plant to meet the electricity needs of Sebesi Island, South Lampung, Indonesia. The availability of solar Energy and limited battery life are the main challenges in providing solar Energy today. Therefore, this study also considers the uncertainty of resources by using the sensitivity factor. This research uses HOMER software. This study assumes operating reserve peak, operating reserve, solar reserve, and lifetime battery life to account for resource uncertainty. This method is very effective in overcoming operational limitations and problems. The research results show that the optimal peak operating reserve, operating reserve, solar reserve, and lifetime battery are 10%, 10%, 10–30%, and 5 years, respectively. To meet the daily electrical energy needs of 505.1 kWh, the minimum net current cost (NPC) and energy cost (COE) are $1.26 million and 0.346 $/kWh, respectively. Therefore, this research succeeded in finding a scenario that takes into account sensitivity factors that are more economical. Compared with a diesel generator (DG) with a capacity of 100 kW, the NPC and COE values are $1.29 million and 0.397 $/kWh. Meanwhile, in terms of technology, solar power systems produce much more energy than DG. This system has an energy of 583,316 kWh/year, while the DG system can produce an energy of 268,469 kWh/year. As a result, this system can also reduce CO2 emissions by 241,812 kg/year. [ABSTRACT FROM AUTHOR]

This work focuses on the structure, working, and testing of a new mixed solar cooker using a linear Fresnel collector, evacuated tube and box‐type cooker. The low‐cost components used in the construction of this cooker can help it satisfy the needs of both urban and rural inhabitants who need steady cooking temperatures above 140°C. A family of five can prepare four meals using this modified solar cooker, which costs about $250. The designed solar cooker was tested by conducting no‐load and full‐load tests. For the no‐load test, the maximum temperature of the absorber plate and oil for the new mixed cooker was recorded as 160.26°C and 172.72°C, respectively. The absorber plate of the new mixed cooker and its oil both reached their highest temperatures during the full‐load test at 141.14°C and 157°C, respectively. The energy efficiency of the new cooker is 58.776%, while its exergy efficiency is 13%. The heat transfer coefficient increased to 100.16 W/m² °C. This cooker provides an additional time savings of 60 min. An improvement of 27.5% in the highest temperature reached was seen when the developed cooker's performance was compared with those reported in the literature. Additionally, the new cooker's heat‐storing capability enables up to 3 h of autonomy. The Levelized Cost of Cooking a Meal for the innovative mixed solar cooker is $0.034 per meal. [ABSTRACT FROM AUTHOR]

In this study, 11 provinces with more than 1 MW solar power plants (SPP) in Turkey have been examined in terms of global solar radiation and power produced. The main objective of this study is to underline the serious differences in technical feasibility analysis conducted by the academic circles and solar energy industrial environments in Turkey. The obtained results were compared with the values operated by the private installation companies in the industry, these were interpreted, and the disagreements were revealed. Moreover, the study reveals some gaps in technical feasibility analysis, which the sector professionals usually ignore in the field. The findings were evaluated in monthly, annual, and seasonal time zones. The present study showed that the analysis, to which private companies in the field refer, is insufficient and the parameters that would guide the investor in detail could not be obtained. More detailed prospection has been obtained within the scope of this study. Considering the whole of our findings, while the most advantageous location for investing in SPPs in Antalya with a total of 97.50 h monthly average sunshine duration and radiation of 59,599.6 W/m2 throughout the year, the most disadvantaged location is Kahramanmaraş with a total monthly average sunshine duration of 80.80 h and a radiation value of 44,810.8 W/m2-year. Antalya is followed by Mardin location (monthly average sunshine duration of 96.10 h and radiation of 59,487.9 W/m2-year) and Karaman (monthly average sunshine duration of 94.40 h and radiation of 58,847.1 W/m2-year). [ABSTRACT FROM AUTHOR]

In renewable energy-sourced power systems, asynchronous motors serve as elements that both produce and consume electricity. The stability and efficiency of the asynchronous motor in renewable energy system should be considered. Although performance optimization studies have been carried out using power circuits that control the asynchronous motor fed with solar energy and control units such as proportional, integral, derivation (PID), and Fuzzy logic; They may be insufficient to eliminate and reduce vibrations in the output values of an induction motor fed with a renewable energy source. Losses occur as the system performance decreases constantly due to oscillations. In this study, an induction motor power system is optimized with the extra control coefficient (ECCA)-PID, which provides semi-linear control for the first time, unlike the power systems controlled by other linear controllers used so far to reduce oscillations, and the vibration losses are eliminated. The speed oscillations, torque oscillations, and oscillation losses of the induction motor in the system are controlled by conventional PID, and Fuzzy logic controllers in order to demonstrate the effectiveness of the proposed method in simulation and experimentation. Then, the results are compared after the proposed method are examined. As a result of the comparisons, while the motor oscillations and losses in the power system continue throughout the control period in traditional control methods, the proposed method reduces the losses to zero in a large part of the control period. [ABSTRACT FROM AUTHOR]

Solar energy measurements are often charted. These charts keep track of the conditions, events, and inspections done on each solar panel. This study describes a paradigm for measuring and monitoring solar energy via the Internet of Things. This service provides monitoring and technical help during corrective inspections within the quality reliability depth services range. These features and monitoring services can provide highly competent, higher-optimization, and excellent services that are safe, fast, and smooth. Compliance with local and international legal regulations, reliability of work, reduction of time and costs spent on corrective inspections, reduction of downtime and production losses, and management of monitoring and testing processes under expert coordination will all benefit from technical support services provided by approved companies for corrective inspections in the company. [ABSTRACT FROM AUTHOR]

In this paper, multi-objective optimization of the hydrogen production ( m ˙ H 2 ) of a solar-based cobalt-chlorine (Co–Cl) thermochemical cycle with grey relational analysis (GRA) has been performed. Monthly total irradiance averages (A), wind velocity (B), receiver height (C), receiver radius (D) and number of heliostats (E) are considered to achieve the highest the useful energy absorbed by the solar receiver ( Q ˙ a b s ), efficiency of the receiver (η r e c ), the overall efficiency of the system (η o v e r a l l) and hydrogen production ( m ˙ H 2 ). Orthogonal experimental design is planned according to L 18 orthogonal array created by Taguchi method. The percent contribution rates (PCR) on the Q ˙ a b s , η r e c , η o v e r a l l and m ˙ H 2 are determined with the help of ANOVA analysis. The optimal parameters are identified as monthly total irradiance average of 143.8 kW h (A 3), wind velocity of 5 m/s (B 2), receiver height of 8 m (C 1), receiver radius of 3 m (D 1) and number of heliostats of 850 (E 3), respectively. The highest Q ˙ a b s , η r e c , η o v e r a l l and m ˙ H 2 values corresponding to A 3 B 2 C 1 D 1 E 3 are obtained as 50.2 GW; 64.1%; 22.2% and 122.59 (tons/month), respectively. The PCR of the A, B, C, D and E parameters influencing the f-factor are determined to be 12.6 %, 1.92 %, 0.48 %, 15.03 %, and 53.20 %, respectively. Also, empirical equations are developed with regression analysis (RA) to estimate the Q ˙ a b s , η r e c , η o v e r a l l , m ˙ H 2 values. The statistical coefficients (R2-value) for training and testing data's are determined in the range of 0.771167–0.99608 for Q ˙ a b s , η r e c , η o v e r a l l and m ˙ H 2 , respectively. • Hydrogen production of a solar-based Co–Cl has been investigated. • Optimization of solar-based Co–Cl determined with Taguchi based GRA. • The η o v e r a l l of solar-based Co–Cl computed as 22.2%. [ABSTRACT FROM AUTHOR]

In this study, a modified solar-Organic Rankine Cycle (ORC) assisted hydrogen production system for two different scenarios was experimentally investigated. In the study, evacuated tube solar collector (ETSC), ORC system, proton exchanger membrane electrolyzer (PEMe) unit is discussed with a holistic perspective. The presented work includes energy and exergy analysis of solar-ORC assisted hydrogen production. According to scenario 1 (S-1), only the case of hydrogen production from the installed system is considered. According to Scenario 2 (S-2), the both electrical energy and hydrogen production from the installed system is examined. As a result of the study, the energy efficiency in S-1 and S-2 operating modes was calculated as 9.553% and 16.02%, respectively. Additionally, the highest exergy efficiency for both scenarios was calculated as 6.129% in the S-2 scenario. Furthermore, hydrogen production amount of the S-1 and S-2 scenarios was calculated as 743.1 kg/annual and 371.5 kg/annual, respectively. • Solar energy based electricity and hydrogen production systems. • The energy efficiency of the S-1 and S-2 systems are calculated as 9.553% and 16.02% under actual operating conditions. • The exergy efficiency of the S-1 and S-2 systems are calculated as 2.32% and 6.129% under actual operating conditions. • According to both scenarios, the highest hydrogen production is calculated as 743.1 kg/annual. [ABSTRACT FROM AUTHOR]

Integrating solar energy into rechargeable battery systems represents a significant advancement towards sustainable energy storage solutions. Herein, we propose a win‐win solution to reduce the shuttle effect of polysulfide and improve the photocorrosion stability of CdS, thereby enhancing the energy conversion efficiency of rGO/CdS‐based photorechargeable integrated lithium‐sulfur batteries (PRLSBs). Experimental results show that CdS can effectively anchor polysulfide under sunlight irradiation for 20 minutes. Under a high current density (1 C), the discharge‐specific capacity of the PRLSBs increased to 971.30 mAh g−1, which is 113.3 % enhancement compared to that of under dark condition (857.49 mAh g−1). Remarkably, without an electrical power supply, the PRLSBs can maintain a 21 hours discharge process following merely 1.5 hours of light irradiation, achieving a breakthrough solar‐to‐electrical energy conversion efficiency of up to 5.04 %. Ex situ X‐ray photoelectron spectroscopy (XPS) and in situ Raman analysis corroborate the effectiveness of this complementary weakness approach in bolstering redox kinetics and curtailing polysulfide dissolution in PRLSBs. This work showcases a feasible strategy to develop PRLSBs with potential dual‐functional metal sulfide photoelectrodes, which will be of great interest in future‐oriented off‐grid photocell systems. [ABSTRACT FROM AUTHOR]

The solar‐driven photocatalytic production of hydrogen peroxide (H2O2) from water and oxygen using semiconductor catalysts offers a promising approach for converting solar energy into storable chemical energy. However, the efficiency of photocatalytic H2O2 production is often restricted by the low photo‐generated charge separation, slow surface reactions and inadequate stability. Here, we developed a mixed‐linker strategy to build a donor‐acceptor‐acceptor (D–A–A) type covalent organic framework (COF) photocatalyst, FS‐OHOMe‐COF. The FS‐OHOMe‐COF structure features extended π–π conjugation that improves charge mobility, while the introduction of sulfone units not only as active sites facilitates surface reactions with water but also bolsters stability through increased interlayer forces. The resulting FS‐OHOMe‐COF has a low exciton binding energy, long excited‐state lifetime and high photo‐stability that leads to high performance for photocatalytic H2O2 production (up to 1.0 mM h−1) with an H2O2 output of 19 mM after 72 hours of irradiation. Furthermore, the catalyst demonstrates high stability, which sustained activity over 192 hours of photocatalytic experiment. [ABSTRACT FROM AUTHOR]

Integrating solar energy into rechargeable battery systems represents a significant advancement towards sustainable energy storage solutions. Herein, we propose a win‐win solution to reduce the shuttle effect of polysulfide and improve the photocorrosion stability of CdS, thereby enhancing the energy conversion efficiency of rGO/CdS‐based photorechargeable integrated lithium‐sulfur batteries (PRLSBs). Experimental results show that CdS can effectively anchor polysulfide under sunlight irradiation for 20 minutes. Under a high current density (1 C), the discharge‐specific capacity of the PRLSBs increased to 971.30 mAh g−1, which is 113.3 % enhancement compared to that of under dark condition (857.49 mAh g−1). Remarkably, without an electrical power supply, the PRLSBs can maintain a 21 hours discharge process following merely 1.5 hours of light irradiation, achieving a breakthrough solar‐to‐electrical energy conversion efficiency of up to 5.04 %. Ex situ X‐ray photoelectron spectroscopy (XPS) and in situ Raman analysis corroborate the effectiveness of this complementary weakness approach in bolstering redox kinetics and curtailing polysulfide dissolution in PRLSBs. This work showcases a feasible strategy to develop PRLSBs with potential dual‐functional metal sulfide photoelectrodes, which will be of great interest in future‐oriented off‐grid photocell systems. [ABSTRACT FROM AUTHOR]

Large amplitude Alfvénic fluctuations, sometimes leading to localized inversions of the magnetic field, called switchbacks, are a common but poorly understood phenomenon in the solar wind. In particular, their origin(s), evolution, and stability within solar wind conditions are yet to be fully understood. Simulations modeling switchbacks have previously studied their stability in 2D. Here, we investigate the decay process of Alfvén wave packets via MHD simulations in 3D by characterizing the effects of system size, aspect ratio, and propagation angle on the decay rate. We show that the initial wave packet is unstable to parametric instabilities that develop compressible and Alfvénic secondary modes in the plane of, and transverse to, the initial wave packet propagation direction. The growth of transverse modes, absent in 2D simulations, increases the decay rate of the wave packet. We finally discuss the implications of our results for lifetime estimates of switchbacks and wave energy conversion in the solar wind. [ABSTRACT FROM AUTHOR]

This study focuses on the hydrothermal synthesis and characterization of Concentration dependent Co 3 O 4 @VO 2 nanocomposites with varying molar ratios of Co 3 O 4 to VO 2 (2:1, 1:1, and 1:2) for efficient hydrogen generation and dye degradation. The structural and morphological characteristics of the prepared nanocomposites were analysed using x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Crystallographic analysis using XRD confirmed the formation of crystalline Co 3 O 4 with a monoclinic structure, while the presence of VO 2 was identified by characteristic peaks in the XPS. Microscopic analysis using SEM and TEM revealed well-dispersed nanocomposites with nanoscale dimensions. Photocatalytic activities were evaluated for hydrogen evolution and dye degradation, with the nanocomposite featuring a 2:1 ratio of Co 3 O 4 to VO 2 (CV-21) demonstrating significantly enhanced performance. CV-21 exhibited a lower onset potential and higher current density for hydrogen evolution (2270μmol/h/g), indicating improved photocatalytic activity. Additionally, it displayed rapid and superior dye degradation (93% within 10 min) under sunlight compared to Victoria blue B (VBB) dye. The Co 3 O 4 @VO 2 nanocomposites, particularly CV-21, demonstrate enhanced photocatalytic performance for hydrogen generation and dye degradation compared to pristine VO 2 and Co 3 O 4. This improvement possibly due to synergistic effects between Co 3 O 4 and VO 2 , optimized structural characteristics, and improved interfacial properties in the nanocomposite structure. These findings highlight the promising potential of Co 3 O 4 @VO 2 nanocomposites, particularly CV-21, for environmental remediation applications. This research underscores the promising prospects of Co 3 O 4 @VO 2 nanocomposites. These materials exhibit remarkable capabilities in sustainable hydrogen production and efficient dye degradation. Their superior photocatalytic performance, exemplified by CV-21 with a 2:1 Co 3 O 4 to VO 2 ratio, signifies their potential for advanced environmental and energy applications. By harnessing these nanocomposites, we can pave the way for greener and more effective solutions in the fields of renewable energy and pollution control. [Display omitted] • Co 3 O 4 @VO 2 nanocomposites with 2:1 ratio showed superior photocatalytic performance. • Highest hydrogen evolution rate: 2270 μmol/h/g under sunlight. • VBB dye degradation reached 93% within 10 min, with rapid rate constant: 0.2715 min−1. • Efficient charge carrier separation and transportation within nanocomposite. • High stability over 5 cycles with 25% performance degradation. [ABSTRACT FROM AUTHOR]

This study explores the improvement of battery longevity in electric vehicles (EVs) by integrating solar photovoltaic (PV) and fuel cell technologies uniquely. The study primarily examines the role of vehicle-integrated PV (VIPV) systems as devices that increase the range of EVs. The research utilizes TRNSYS for solar radiation analysis and MATLAB for vehicle dynamics to evaluate several arrangements of PV panel placement, including various positions on the vehicle's exterior surfaces. An exhaustive examination is carried out to determine the most suitable positioning of PV panels, considering variables such as tilt and azimuth angles, as well as the effectiveness of energy capture. In addition, the study investigates the efficiency of various PV panel variants (Gallium Arsenide, Copper Indium Gallium Selenide, and Cadmium Telluride) throughout Europe, considering geographical and seasonal fluctuations in solar energy collection. The study analyzes the effects of using PV panels on battery longevity by examining the battery's current amplitude and fluctuations using the Worldwide Harmonized Light Vehicles Test Cycle (WLTC). The study provides detailed results for various cases in the proposed topology. Results have shown that with VIPVs, the battery current amplitude and its fluctuations can be reduced by up to 7.3 % and 2.5 %, respectively. • Solar PV/fuel cell integration is investigated for electric car battery longevity. • The role of vehicle-integrated PV systems is investigated concerning range. • PV side analysis numerically included several technologies, locales, and seasons. • The improvement of battery current fluctuations aligns with obtained findings. [ABSTRACT FROM AUTHOR]

The extensive use of coal and oil for heating, electricity generation and cooling of buildings contributes to various environmental problems, both locally and globally. One of the feasible solutions to the climatic issues currently in this region is using sustainable energy sources. Hydrogen is an alternative option to fossil resources generated from sustainable energy sources. It is a form of energy that is both ecologically safe and sustainable. Hydrogen may now be produced in several different ways, including by reforming hydrocarbons, the Electrolysis of water, and Steam reforming of fossil fuels. However, because there is a finite supply of fossil fuels and a change in climate conditions due to the emission of CO 2 & other contaminants, there has been a focus on producing hydrogen using renewable resources. This study reviews an H 2 production system that combines geothermal & solar energy, the two primary renewable energy sources and a hybrid solar-geothermal system. This study looked into different aspects, like the working fluid for water electrolysis, the geothermal fluid temperature, and the type of power cycle. Comparative analysis was also performed on numerous GPPs, including flash, ORC cycles, binary, flash-binary, and solar collectors; this covers investigations on the rates and costs of producing hydrogen. • This paper looks at three different approaches of producing hydrogen using renewable energy sources. • An innovative renewable energy system that depends on solar and geothermal power. • An integrated system consists of geothermal and solar energy, an electrolyzer, and a fuel cell unit. • Hydrogen production as a function of design factors including working fluid, electrolysis temperature, and cycle type. • Producing hydrogen from geothermal and solar energy is a cost-effective and potentially profitable solution. [ABSTRACT FROM AUTHOR]

The Royal Society recently highlighted the huge energy storage needs for the United Kingdom to make stable a grid only fed by solar and wind energy, which must come mostly from hydrogen energy storage. Similar results are obtained for NEOM City modeling the operation of a 50/50 wind and solar energy production, adopting an efficiency for green hydrogen production of 0.75, and an efficiency for power generation from the hydrogen of 0.55. The analysis for NEOM City suggests that with an evenly distributed combined wind and solar generating capacity of 30 GW, a dispatchable annual energy contribution of 60 TWh to the grid is attainable. This presupposes the availability of hydrogen energy storage amounting to no less than 8 TWh and electrolyzers with a power capacity of 22 GW. Ideally, the hydrogen power generation facility should have a nominal power of 13.5 GW. Integrating an intermediate high-efficiency energy storage system, such as flow batteries, between wind and solar generators and electrolyzers can significantly cut the power of the electrolyzers by up to 80 %. A high-efficiency combined cycle gas turbine power plant is then proposed to feed back the grid burning a mixture of green hydrogen and natural gas. By using an almost off-the-shelf technology, gradually shifting towards higher hydrogen contents as green hydrogen becomes more readily available, this solution delivers the lowest possible life cycle CO 2 emission at any time during the progress of the project. NEOM hydrogen city by Bing Image Creator. Generated with AI ∙ 19 November 2023. [Display omitted] [ABSTRACT FROM AUTHOR]

Present paper aims to investigate effects of nanoparticle addition to thermal oil of parabolic trough collectors which are integrated to Kalina cycle for electricity generation to run an alkaline electrolyzer for hydrogen production. Thermodynamic models for Kalina cycle, thermal model for parabolic collectors and electrochemical models for water electrolyzer are developed for overall plant modeling. Three types of nanoparticles including: copper oxide, alumina and titanium oxide are considered and overall plant performance is investigated using these nanoparticles and is compared with basefluid. The nanofluid thermophysical properties are evaluated as a function of nanoparticles' properties, volume fraction and the base fluid properties. The effects of key variables such as nanoparticle volume fraction, collector inlet temperature, evaporation pressure and ammonia concentration of Kalina system were evaluated on hydrogen production as well as exergetic efficiencies. Results revealed greater positive influence for CuO compared to TiO 2 and Al 2 O 3 on performance improvement for both hydrogen generation and its exergetic efficiency. Also, compared to basefluid (without nanoparticles) case, it was found that CuO particles result in a solar-to-H 2 exergy efficiency improvement by 4.7%. Using this nanofluid with a volume fraction of 5%, the H 2 production rate enhances from 0.633 kg / h to 0.664 kg / h , indicating 4.9 % improvement. • An alkaline electrolyzer-based hydrogen production plant powered by PTC is modeled. • Three types of nanoparticles are employed for hydrogen production enhancement. • Copper oxide nanoparticles are found to be better than titanium oxide and alumina. • Nanoparticles are applied to enhance the PTC thermal performance. • Hydrogen production rate can be enhanced by 4.9 % using CuO nanoparticles. [ABSTRACT FROM AUTHOR]

The growing popularity of artificial intelligence approaches has led to their application in a wide range of engineering fields. The most widely used artificial intelligence tool, artificial neural networks, can be used to predict data with high accuracy. An artificial neural network approach is being used to predict effective and accurate thermal conductivity and viscosity models for hybrid nanofluid systems. Here, new types of correlations relating to the thermophysical properties of Fly Ash–Cu nanoparticles with diameter sized 15.2 nm and which are temperature-dependent are developed. The highest thermal conductivity and viscosity values were obtained for hybrid nanofluids with a mixture ratio of 20:80, with maximum amplification exceeding 83.2% and 65%, respectively, over the base fluid. The Fly Ash–Cu/water hybrid nanofluid's viscosity and thermal conductivity are evaluated for a concentration range of 0–4%. The evaluation of the Fly Ash–Cu/water hybrid nanofluids system at concentrations ranging from 0 to 4% most likely entails a scientific or engineering study aimed at understanding the behavior and properties of this nanofluid mixture. Nanoparticles can agglomerate or settle in the base fluid over time, compromising the stability of the nanofluids. Researchers may be interested in determining how varied quantities of Fly Ash and Cu nanoparticles affect the nanofluid's stability and sedimentation behavior. The heat transfer potential is examined within the optimistic range of temperatures of 30–80∘C. Many fruitful results for turbulence and solar energy have been drawn. The Mouromtseff number achieved an optimal value for all concentration levels. The heat transfers of turbulent flow and thermal conductivity of hybrid nanofluids increase with the augmented values of concentrations and temperature. Researchers found an increase in thermal conductivity of hybrid nanofluids at 0–4% concentrations, potentially impacting heat transfer applications. The conclusion explores the potential integration of the developed correlations and neural network model into practical engineering or industrial applications involving solar energy and turbulence appliances. In this work, we extend the work of Kanti et al. [Sol. Energy Mater. Sol. Cells 234 (2022) 111423] which is on the properties of water-based fly ash-copper hybrid nanofluid for solar energy applications. [ABSTRACT FROM AUTHOR]

Over the past few decades, many universities have turned to using microgrid systems because of their dependability, security, flexibility, and less reliance on the primary grid. Microgrids on campuses face challenges in the instability of power production due to meteorological conditions, as the output of renewable sources such as solar and wind power relies entirely on the weather and determining the optimal size of microgrids. Therefore, this paper comprehensively reviews the university campuses' microgrids. Some renewable energy sources, such as geothermal (GE), wind turbine (WT), and photovoltaic (PV), are compared in terms of installation costs, availability, weather conditions, efficiency, environmental impact, and maintenance. Furthermore, a description of microgrid systems and their components, including distributed generation (DG), energy storage system (ESS), and microgrid load, is presented. As a result, the most common optimization models for analyzing the performance of campus microgrids are discussed. Hybrid microgrid system configurations are introduced and compared to find the optimal configuration in terms of energy production and flexibility. Therefore, configuration A (Hybrid PV- grid-connected) is the most common configuration compared to the others due to its simplicity and free-charge operation. [ABSTRACT FROM AUTHOR]

This article discusses the issue of diagnosing low-power solar power plants using the five-valued (5VL) state evaluation {4, 3, 2, 1, 0}. We address in depth how the 5VL diagnostics built upon 2VL, 3VL, and 4VL—two-valued diagnostics, three-valued logistics, and four-valued diagnostics. Logic (5VL) assigns five state values to the range of signal value changes, and these states are completely operational ({4}), incomplete ({3}), critical efficiency ({2}), and pre-fault efficiency ({1}). For the identical ranges of diagnostic signal values, all three of the applied state valence logics interpret failure as changes outside of their permitted ranges. Diagnostic procedures made use of an AI-based DIAG 2 system. This article's goal is to provide a comprehensive overview of the DIAG 2 intelligent diagnostic system, including its architecture, algorithm, and inference rules. Diagnosis with the DIAG 2 system is based on a well-established technique for comparing diagnostic signal vectors with reference signal vectors. A differential vector metric is born out of this examination of vectors. The input cells of the neural network implement the challenge of signal analysis and comparison. It is then possible to classify the object components' states in the neural network's output cells. Based on the condition of the object's constituent parts, this approach can signal whether those parts are working, broken, or urgently require replacement. [ABSTRACT FROM AUTHOR]

Electricity consumption in homes is on the rise due to the increasing prevalence of home appliances and longer hours spent indoors. Home energy management systems (HEMSs) are emerging as a solution to reduce electricity consumption and efficiently manage power usage at home. In the past, numerous studies have been conducted on the management of electricity production and consumption through solar power. However, there are limited human-centered studies focusing on the user's lifestyle. In this study, we propose an Intelligent Home Energy Management System (i-HEMS) and evaluate its energy-saving effectiveness through a demonstration in a standard house in Korea. The system utilizes an IoT environment, PID sensing, and behavioral pattern algorithms. We developed algorithms based on power usage monitoring data of home appliances and human body detection. These algorithms are used as the primary scheduling algorithm and a secondary algorithm for backup purposes. We explored the deep connection between power usage, environmental sensor data, and input schedule data based on Long Short-Term Memory network (LSTM) and developed an occupancy prediction algorithm. We analyzed the use of common home appliances (TV, computer, water purifier, microwave, washing machine, etc.) in a standard house and the power consumption reduction by the i-HEMS system. Through a total of six days of empirical experiments, before implementing i-HEMS, home appliances consumed 13,062 Wh. With i-HEMS, the total consumption was reduced to 10,434 Wh (a 20% reduction), with 9060 Wh attributed to home appliances and 1374 Wh to i-HEMS operation. [ABSTRACT FROM AUTHOR]

Egypt has the potential to generate a significant amount of energy from renewable technologies, in particular solar PV, concentrated solar power (CSP), and onshore and offshore wind. The energy sector is reliant on fossil fuels, particularly natural gas, for electricity production and is at risk of locking itself into a high carbon pathway. Globally, reducing greenhouse gas (GHG) emissions associated with national energy sectors is a target outlined in the UN's Paris Agreement. To reduce carbon dioxide (CO2) emissions associated with a higher dependence on fossil fuels, Egypt must consider upscaling renewable energy technologies (RETs) to achieve a clean energy transition (CET). This research modelled six scenarios using clicSAND for OSeMOSYS to identify the technologies and policy target improvements that are needed to upscale RETs within Egypt's energy sector. The results showed that solar PV and onshore wind are key technologies to be upscaled to contribute towards Egypt's CET. The optimal renewable target is the International Renewable Energy Agency's (IRENA) target of 53% of electricity being sourced from RETs by 2030, which will cost USD 16.4 billion more up to 2035 than Egypt's current Integrated Sustainable Energy Strategy (ISES) target of 42% by 2035; it also saves 732.0 MtCO2 over the entire modelling period to 2070. Socio-economic barriers to this transition are considered, such as recent discoveries of natural gas reserves combined with a history of energy insecurity, political instability impacting investor confidence, and a lack of international climate funding. The paper concludes with policy recommendations that would enable Egypt to progress towards achieving a CET. [ABSTRACT FROM AUTHOR]

The utilization of phase change materials (PCMs) in solar water heating systems (SWHS) has undergone notable advancements, driven by a rising demand for systems delivering superior performance and efficiency. Extensive research suggests that enhancing heat transfer (HTE) in storage systems is crucial for achieving these improvements. This review employs a bibliometric analysis to track the evolution of HTE methods within this field. While current literature underscores the necessity for further exploration into hot water generation applications, several methodologies exhibit significant promise. Particularly, strategies such as fins, encapsulation, and porous media emerge as prominent HTE techniques, alongside nanofluids, which hold the potential for augmenting solar water heating systems. This review also identifies numerous unexplored techniques awaiting investigation, aiming to pave new paths in research and application within the field of hot water generation. It highlights methods that could be used independently or alongside predominantly used techniques. [ABSTRACT FROM AUTHOR]

Thermal energy storage (TES) is crucial in bridging the gap between energy demand and supply globally. Concentrated Solar Power (CSP) plants, employing molten salts for thermal storage, stand as an advanced TES technology. However, molten salts have drawbacks like corrosion, solidification at lower temperatures, and high costs. To overcome these limitations, research is focusing on alternative TES materials such as ceramic particles. These solids match molten salts in energy density and can withstand higher temperatures, making them well-suited for CSP systems. This study revolves around subjecting Solar Salt alone and Solar Salt alongside Volcanic Ash (VA) and Electric Arc Furnace Slag (EAFS) to a comprehensive thermal cycling test. This test is designed to assess the compatibility over the thermal cycles of the Solar Salt and the Solar Salt in contact with these solids in a CSP plant with a thermocline configuration. With a final thermal and chemical evaluation, our observations indicate that EAFS and VA demonstrate promising compatibility but an increase in the reduction rate of the Solar Salt due to a catalyst effect from EAFS in contact with the salt. No discernible alterations were detected in the properties of either the solid materials or solar salt when combined. [ABSTRACT FROM AUTHOR]

The optimal designing of the hybrid energy system (HES) is a challenging task due to the multiple objectives and various uncertainties. Especially for HES, primarily powered by solar energy, the reference solar radiation data directly impact the result of the optimization design. To incorporate the stochastic characteristics of solar radiation into the sizing process, a data-driven stochastic modeling method for solar radiation is proposed. The method involves two layers of stochastic processes that capture the intraday variation and daily evolution of solar radiation. First, the clearness index (CI) is introduced to describe the radiation intensity at different times. Then, the daily clearness state (DCS) is proposed, based on the statistical indicators of the intraday CI. The Markov model is used to describe the stochastic evolutionary characteristics between different DCSs. The probabilistic distribution of the CI under different DCS is obtained based on the diffusion kernel density estimation (DKDE), which is used for the stochastic generation of the CI at various times of the day. Finally, the radiation profile required for the optimal design is obtained by the stochastic generation of the DCS sequences and the intraday clearness index under corresponding states. A case study of an off-grid solar-powered HES is provided to illustrate this methodology. [ABSTRACT FROM AUTHOR]

This research paper presents a comprehensive study on the implementation of photovoltaic (PV) energy systems at Al-Abrar Mosque in Saudi Arabia. The primary objective was to explore optimal regional solar power strategies. By synergistically integrating technical evaluations of the PV system with economic analyses, including the payback period and levelized cost of energy (LCOE), alongside an investigation of net metering and net billing scenarios, we delineated a pathway toward achieving net zero billing for the mosque's energy requirements. This study examined two scenarios: Scenario I involved net metering, while Scenario II explored net billing. Our theoretical and simulation results, derived from detailed analyses conducted using PVsyst software, unequivocally demonstrated the superiority of net metering for this specific application. With net metering, the mosque's energy needs can be efficiently met using minimal infrastructure—comprising only 34 photovoltaic modules and a single inverter. In contrast, net billing requires significantly higher resource demands, underscoring the economic and spatial advantages of net metering. Additionally, the payback period for Scenario I is 7.9 years, while for Scenario II, it extends to 87 years. Through rigorous simulations, this study reaffirmed the practicality and feasibility of the net metering approach within the context of Saudi Arabia. Furthermore, our research provides actionable insights for implementing sustainable solutions at specific sites, such as the Al-Abrar Mosque, and contributes to advancing renewable energy knowledge in the region. [ABSTRACT FROM AUTHOR]

The precipitation-hardenable nickel-based superalloy Rene 41 exhibits remarkable mechanical characteristics and high corrosion resistance at high temperatures, properties that allow it to be used in high-end applications. This research paper presents findings on the influence of thermal shocks on its microstructure, hardness, and thermal diffusivity at temperatures between 700 and 1000 °C. Solar energy was used for cyclic thermal shock tests. The samples were characterized using microhardness measurements, optical microscopic analysis, scanning electron microscopy coupled with EDS elemental chemical analysis, X-ray diffraction, and flash thermal diffusivity measurements. Structural transformations and the variation of properties were observed with an increase in the number of shocks applied at the same temperature and with temperature variation for the same number of thermal shocks. [ABSTRACT FROM AUTHOR]