Solar System Research Articles

Solar thermal applications of graphene-based block-ring resonator solar absorber using TiC–W materials

Solar absorbers enable the use of solar energy, a renewable and plentiful resource, minimizing reliance on finite fossil fuels and contributing to sustainable energy practices. The solar absorber that is studied here has an average absorptance of 96.85 % with a simple design and inexpensive materials. This design has two layers of resonator and active layer Block Ring Base Solar Absorber (BRBSA) structure. This study employs tungsten (W) as a resonator and titanium carbide (TiC) as a dielectric layer. The absorption spans from 100 to 3200 nm, with an average absorption exceeding 94 % across the entire structure. Notably, over 97 % of absorption occurs within the range of 210–710 nm, and the highest absorption, reaching 99.9 %, is observed in the wavelength range of 1510–1650 nm. The structure demonstrates high absorption rates across various regions, including 95.85 % in the UV region, 97.89 % in the visible, 95.73 % in the near-infrared, 95.87 % in the mid-infrared, and 89.56 % in the far-infrared region. After analyzing various potential variations of the proposed structure, an optimal design was identified. The parametric study was conducted to determine the optimal physical properties. Additionally, the electric field intensity analysis confirmed the proposed structure's broadband and constant absorption response. This Block Ring Base Solar Absorber has various uses, including solar drying systems, cookers, vaporizers, and warmers.

Light-assisted thermochemical reduction of CuFe2O4 within a photo-thermogravimetric analyser for solar fuel production

The solar thermochemical cycle has emerged as a promising clean energy technology that enables the splitting of water for solar fuel production. However, conventional two-step thermochemical cycles using single-metal oxides require high operating temperatures above 1000 °C, especially for the reduction step. Typical solar thermal systems struggle to meet such high temperature requirements, making it vital to reduce the operating temperature. To find a solution enabling lower temperature requirements, we propose a photo-thermochemical reduction (PTR) strategy, which employs light illumination as assistance, combining both thermally induced and photo-induced effects for more generation of oxygen vacancies (VOs), within the oxygen carrier copper ferrite (CuFe2O4). Experimental studies were performed in a specially-designed photo-thermogravimetric analyser (photo-TGA) that directly measures the weight change of solid reactants under direct light illumination. The results indicate that the PTR achieves a decrease of nearly 40 °C in temperature requirements, giving a higher oxygen release of 21% compared to that driven by pure thermal heating at 800 °C. We also measured an increase of 0.09 in the non-stoichiometry parameter δ in the photo-TGA. Additionally, we observed that oxygen release increases distinctly with the light intensity of incident illumination. From the viewpoint of spectral ranges, ultraviolet and visible light illumination give the primary boost to the generation of photo-induced VOs. These results demonstrate the effective assistance of concentrated solar energy to enhance the two-step thermochemical cycle for solar fuel production at lower temperatures.

Acceleration of solar wind particles due to inertial Alfvén waves

Gaining an understanding of the effects and dynamics of the solar wind is crucial for the study of space weather, Earth's magnetosphere, spacecraft protection, the dynamics of the Solar System, and various other subjects. Observations show that Alfvén waves effectively transfer energy to resonant particles. This study demonstrates how inertial Alfvén waves deliver their energy to resonant plasma particles in different solar environments under certain conditions. The analysis shows that inertial Alfvén waves experience more rapid damping with increasing parallel wavenumber, ambient magnetic field strength, and particle number density, coupled with a decrease in temperature. The rate of energy transfer to resonant particles intensifies with higher temperatures and reduced parallel wavenumber and particle number density. Particles with higher initial velocities actively participate in Landau damping, especially in regions with a stronger ambient magnetic field.

A synergistic approach to optimizing the performance of a concentrating solar segmented variable area leg thermoelectric generator using numerical methods and neural networks

AbstractThis study presents an optimized design for segmented variable area leg thermoelectric modules using finite element methods and Bayesian regularized neural networks. We explored the impact of geometry and thermal parameters on module performance using ANSYS software, identifying optimal parameters for power output and efficiency. Key findings revealed the higher influence of geometric parameters and confirmed the advantages of segmented thermoelectric generators for high-temperature applications like concentrated solar systems. With this optimization, power output and efficiency of the module increased by 875% and 165%, respectively, under 25 Suns. To refine the optimization process, a Bayesian regularized neural network was utilized, proving effective in predicting module performance with a low mean squared error and high coefficient of determination. This research provides important insights into high-performance thermoelectric modules for sustainable energy applications, demonstrating the significant role of advanced computational methods in energy solutions.

Solar photovoltaic automatic tracking device based on IoT and BDS

Solar photovoltaic automatic tracking device based on IoT and BDS

The Influence of Different Solar System Planetary Ephemeris on Pulsar Timing

Abstract The pulsar timing offers a comprehensive avenue for exploring diverse topics physics and astrophysics. High-precision solar system planetary ephemeris crucial for pulsar timing as it provides the positions and velocities of solar system planets include the Earth. However, it is inevitable that inherent inconsistencies exist in these ephemerides. Differences between various ephemerides can significantly impact pulsar timing and parameter estimations. Currently, pulsar timing highly depend on the JPL DE ephemeris, for instance, the Pulsar Timing Array (PTA) data analysis predominantly utilizes DE436. In this study, we examine inconsistencies across various ephemeris series, including JPL DE, EPM, and INPOP. Notably, discrepancies emerge particularly between the current ephemeris DE436 and the earliest released ephemeris DE200, as well as the most recent ephemerides, e.g. DE440, INPOP21A, and EPM2021. A further detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric Time of Arrivals (TOAs) is presented in this study. Our researches reveal that variations in the Roemer delays across different ephemerides lead to distinct differences. The timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters, leading to inconsistent fitting estimates, suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

Comprehensive Evaluation of Decarbonization Technologies: A Case Study of Residential Buildings in Zhuzhou City, China

Efficient carbon emission reduction technologies in buildings are necessary for achieving the “Dual carbon” goal in China. In this study, a comprehensive evaluation model is proposed to assess the effect of carbon emission reduction based on the analytic hierarchy process–entropy weight–coefficient of variation model which takes newly built residential buildings in Zhuzhou City as the research object. The results show that the preferred materials for the roof and exterior walls of the building’s envelope structure were flame-retardant extruded polystyrene boards, and porous shale bricks were preferred as the main materials for the exterior walls. In addition, the rooftop solar photovoltaic system and energy-saving air conditioning technology were suitable in terms of being renewable and were better utilized. In the end, carbon emissions were significantly reduced when using the building decarbonization technologies. This study provides a new reference for choosing materials and technologies for the design of residential buildings in Hunan Province and even other regions with hot summers and cold winters.

Low-carbon scheduling of electricity consumption in wastewater treatment plant by using photovoltaic system

Sewage treatment as a high energy consumption industry, its electricity consumption accounts for 3 % of the total electricity consumption of society. That means significant greenhouse gas emissions. In the context of China's goal of “reaching carbon peak by 2030 and achieving carbon neutrality by 2060”, reducing the energy consumption of wastewater treatment systems has emerged as an important issue in recent years. In this paper, the GPS-X simulation software was employed to conduct a simulation study of a modified Anoxic-Aerobic-Oxic wastewater treatment plant (WWTP) in Wuhan, and the response surface methodology (RSM) was utilized to ascertain the interactive effects of DO, IRF, ERR, and SD on the effluent quality, thereby identifying the operational parameters that minimize energy consumption while maintaining satisfactory effluent quality. Additionally, the PVsyst software was employed to design the solar power generation system of the WWTP and analyze its power generation potential. On this basis, through the coupling of photovoltaic power, electricity load, time-of-use pricing, and the water quality simulation model, and taking the WWTP data in September as a case study, the electricity usage strategies under various illumination conditions were formulated. The aim is to maximize the use of photovoltaic power to reduce the cost and carbon emissions of the WWTP. The results show that the optimal combination of operational parameters, including an external reflux ratio of 0.3, the internal recycle flow of 50,000 m3/d, and the sludge discharge of 448 m3/d, resulted in a reduction in power of 208.5 kW, and after the combination optimization of operational parameters and electricity utilization, the operation cost of the WWTP in September was reduced by 40 % ∼ 60 %, and the carbon emission attributable to electricity was reduced by 30 % ∼ 50 %.

CONCEPTUAL MODEL OF A NANOSATELLITE WITH LASER BEAM TRANSMISSION AND ITS IMPORTANCE IN RENEWABLE ELECTRICAL POWER HARVESTING

The concept of placing huge solar-powered satellite systems (SPS) in space represents one of several new technology options that could provide large-scale, green base power to terrestrial markets. NASA has already launched the multi-megawatt SSP systems and wireless power transmission (WPT) for government missions and commercial markets (in space and on the ground). In the new space approach satellite technology Nanosatellites with benefits such as low price, resource use, and compatibility with COTS, have huge potential to be the next generation of renewable electrical solar power harvesting satellite systems. With that in mind, it is important to conduct research and development processes for achieving high-efficiency satellite systems. As a result, an initial conceptual model of the new generation low earth orbit nanosatellite with solar power harvesting to laser beam conversion and transmission sub-system was developed with an estimated solar radiation harvesting calculus, part selection along with the structural scheme and its working principle have been proposed.

A novel optimal identification of various solar PV cell parameters by using MRDT controller

At present, Renewable Energy Sources (RES) utilization keeps on increasing because of their merits are more availability in the atmosphere, easy energy harvesting, less maintenance expenses, plus more reliability. Here, the solar power generation systems are utilized for supplying the energy to the local consumers. The accurate, and efficient solar power supply to the customers is a very important factor to meet the peak load demand. The accurate power generation of the sunlight system completely depends on its accurate parameters extraction. In this work, a Modified Rao-based Dichotomy Technique (MRAODT) is introduced to identify the actual parameters of the different PV cells which are PWP 201 polycrystalline, plus RTC France. The proposed MRAODT method is compared with the other existing algorithms which are the teaching and learning algorithm, African vultures, plus tuna intelligence algorithm. Finally, from the simulation results, the MRAODT gives superior performance when associated with the other controllers in terms of parameters extraction time, accuracy in the PV cells parameters identification, plus convergence time of the algorithm.

Bremsstrahlung power conversion for fusion power and propulsion in space

Centrifugally confined Direct Fusion Drive propulsion has the capability of greatly advancing humanity’s ability to traverse and explore the solar system. p-11B is a promising fusion fuel to use in such a system because the reaction is aneutronic. However, a large amount of bremsstrahlung radiation is produced and must be converted into electricity to power the electric field used to help confine the fusion plasma. This work details an idealized analytical model to determine the viability of using a thermionic energy converter for this purpose. The model finds a maximum power density of 105W/m2 with a Carnot efficiency of 30%. The required electric and magnetic fields to produce net positive fusion power are >350MV/m and ∼30T respectively. This data is then used to discuss the feasibility of using p-11B as a fusion fuel for Direct Fusion Drive.

Sharp Rise in Cosmic Ray Irradiation of Organisms on Earth Caused by a Nearby SN Shockwave Passage.

The work considers the modelling of nearby supernova (SN) effects on Earth's biosphere via cosmic rays (CRs) accelerated by shockwaves. The rise of the radiation background on Earth resulted from the external irradiation by CR high-energy particles and internal radiation in organisms by the decay of cosmogenic 14C is evaluated. We have taken into account that the CR flux near Earth goes up steeply when the shockwave crosses the Solar System, while in previous works the CR transport was considered as purely diffusive. Our simulations demonstrate a high rise of the external ionization of the environments at Earth's surface by atmospheric cascade particles that penetrate the first 70-100 m of water depth. Also, the cosmogenic 14C decay is able to irradiate the entire biosphere and deep ocean organisms. We analyzed the probable increase in mutation rate and estimated the distance between Earth and an SN, where the lethal effects of irradiation are possible. Our simulations demonstrate that for SN energy of around 1051 erg the lethal distance could be ∼18 pc.

Performance evaluation of off-grid solar systems for critical medical instruments in remote regions

In areas with limited access to electricity or during power outages, ensuring continuous and reliable use of grid-powered electrical instruments is challenging, especially in remote emergency centers. A stable source of electricity is crucial to prevent disruptions in power supply, as they can lead to severe medical complications, jeopardize patient well-being, and even result in fatal incidents. To address this issue, integrating renewable electricity sources such as off-grid solar systems into existing power supply infrastructure can be a viable solution. Recent studies suggest that off-grid solar systems can be reliable and sustainable options for powering medical facilities, particularly in areas lacking uninterrupted grid connectivity. Therefore, this research aims to evaluate the feasibility, benefits, and challenges of integrating off-grid power to support critical medical instruments. Based on an extensive literature review, interviews with experts, and surveys among relevant users, this study finds that the system has the capability to maintain a consistent, dependable power supply, even during adverse weather conditions. Cost and feasibility are highlighted as paramount considerations, based on surveys and focus group results. The study concludes that off-grid solar systems offer an economical, low-maintenance, and environmentally sustainable alternative for remote medical facilities. Finally, this study proposes recommendations to optimize critical device performance during power outages and improve overall system functionality and efficiency.

Advancing solar-powered hybrid FO-MD desalination: Integrating PVT collectors and PCM for sustainable water production in residential building

The global focus on water desalination using solar energy is particularly pronounced today. Previous studies have affirmed the efficiency of the Forward Osmosis (FO) and Membrane Distillation (MD) hybrid desalination system. The Photovoltaic Thermal (PVT) solar system, which generates both thermal and electrical energy, is complemented using Phase Change Material (PCM). PCM, known for storing and releasing significant heat during phase change, is used in the evening to meet the thermal needs of the system. Additionally, an integrated battery system stores the electrical energy generated by PVT, ensuring the system's electricity requirements are sustained during the night. A comprehensive numerical model, PVT-PCM-FO-MD, has been developed to analyze the proposed system. Operating seamlessly under natural conditions for a typical day on March, June and September, the proposed system can produce freshwater continuously over a 24-hour period. To assess system performance, three PCM thicknesses (2 cm, 4 cm, and 6 cm) were employed. Designed for small-scale applications, this system is well-suited for brackish water desalination in remote areas. Notably, the highest water production recorded was 213.25 L during a 24-hour operation and the MD unit exhibited an impressive 83.78 % evaporation efficiency during the typical day on June, with nighttime efficiency reaching 37.07 %, specifically at 3 am, utilizing a 2 cm PCM thickness in the solar energy system and it was 37.22 % at the same hour and PCM thickness in September. This study further explores the impact of initial brackish water salinity on water production after 24 h and investigates the influence of the initial draw solution concentration in the draw tank on desalinated water production. The study found that despite varying initial salinity levels, the difference in water produced at the end of the day was not exceeding 1.6 L.

A Simulation Study of Hybrid Solar Drying Chamber for Agriculture Product

Hybrid solar drying chamber is an application that is widely used today for agriculture products because it can promise the hygiene of the product. However, drying chambers nowadays still lack uniformity in drying products within a drying chamber, leading to food wastage and compromised product quality. This study aims to design an innovative hybrid solar drying chamber system and investigate the uniformity of temperature and velocity within the chamber using Computational Fluid Dynamics (CFD). The methodology involves validating the simulation results by comparing them with existing journal data, with a validation error of less than 5%. A new design is proposed after the validation process, considering factors such as tray arrangement and air inlet size. The results show that a tray arrangement with 0.20 m spacing between each tray provides better uniformity in temperature and air velocity distribution compared to other arrangements. Additionally, an inlet size of 0.05 m2 demonstrates the most suitable temperature distribution for drying purposes, falling within the ideal range of 318 K to 343 K. The study showed that the performance of the drying chamber under different operating conditions has consistent temperature distribution and is suitable for uniform drying. Overall, the proposed hybrid solar drying chamber system offers improved temperature control and uniformity for effective drying process.

Copper and zinc isotope compositions of pristine eucrites as analogues for differentiated planetary feedstocks

Preferential enrichment of the heavier isotopes of moderately volatile elements (MVE) in samples from asteroids and the Moon have been attributed to volatile loss during the formation and differentiation of their parent bodies. Analogs for planetary feedstocks include the howardite-eucrite-diogenite meteorites, which originate from a differentiated planetesimal or planetesimals, likely including (4) Vesta. Complications arise in the interpretation of volatile depletion in these meteorites, however, due to post-crystallization processes including metamorphism and later impacts that acted upon them. We present new coupled Cu and Zn isotope data for a suite of eucrites that, when combined with published data, show significant ranges (δ65Cu = -1.6 to +0.9‰; δ66Zn = -7.8 to +13.5‰). Exclusion of eucrites that have been affected by metamorphism, impact contamination or surface condensation of isotopically light Zn and Cu leads to a range of ‘pristine’ compositions (δ66Zn = +1.1 ± 2.3‰; δ65Cu = +0.5 ± 0.5‰; 2 St. Dev.), implying inherent MVE variability within the eucrite parent body. As low-mass differentiated bodies, Vesta and the Moon represent endmembers in planet evolution. For the Moon, extensive volatile loss can be explained by a cataclysmic giant impact origin and later magma ocean crystallization. In contrast the parent body of eucrite meteorites likely heterogeneously lost volatile elements and compounds during differentiation. Vesta as the potential source of eucrite meteorites offers an important endmember composition for likely feedstocks to planets, representing the remaining vestige of what was likely to have been a larger population of differentiated objects in the inner Solar System shortly after nebula accretion. Mixing contributions of non-carbonaceous and carbonaceous chondrites constrained by nucleosynthetic Zn isotope anomalies suggests a significant fraction of Earth's accretion could have come from volatile-poor and differentiated planetary feedstocks that would have had limited effects on the bulk silicate Earth (BSE) Zn isotope composition. Furthermore, volatile-poor feedstocks cannot explain the BSE Cu isotope composition, which instead may have been modified by terrestrial core formation. Pristine eucrites offer key insights into early planetesimal differentiation and the role of volatile loss on small mass bodies within nascent solar systems.

Terrestrial planet formation from a ring: Long-term simulations accounting for the giant planet instability

The process leading to the formation of the terrestrial planet remains elusive. In a previous publication, we have shown that, if the first generation of planetesimals forms in a ring at ∼1 AU and the gas disk's density peaks at the ring location, planetary embryos of a few martian masses can grow and remain in the ring. In this work, we extend our simulations beyond the gas-disk stage, covering ∼200 Myr and accounting for the phase of giant planet instability, assumed to happen at different times. About half of the simulations form a pair of Venus and Earth analogues and, independently, about 10% form a Mars analogue. We find that the timing of the giant planet instability affects statistically the terrestrial system's excitation state and the timing of the last giant impacts. Hence a late instability (∼60 to 100 Myr after the Solar system's birth) is more consistent with a late Moon-formation time, as suggested by radioactive chronometers. However, the late veneer mass (LVM: mass accreted after the last giant impact) of Earth-sized planets suffering a giant impact after 80 My is usually an order of magnitude lower than the value inferred from geochemistry. In addition, the final angular momentum deficit (AMD) of the terrestrial planets tends to be too high. We tested the effect on the final AMD of the generation of debris during collisions and found that it is too small to change these conclusions. We argue that the best-case scenario is that the Moon-forming event occurred between 50 and 80 My, possibly just following the giant planet instability.

Novel cellulose-based films with highly efficient photothermal performance for sustainable solar evaporation and solar-thermal power generation

Solar-driven interfacial evaporation has received substantial attention in a variety of applications, including water purification, seawater desalination, and energy production. However, creating a straightforward, adaptable, and scalable method for correctly integrating hybrid solar-thermal systems continues to be a challenging task. Herein, we propose an economical, scalable, and environmentally friendly approach for achieving synergistic coupling of interfacial solar energy conversion for evaporation and low-grade thermal energy conversion to electricity by incorporating zinc oxide (ZnO) nanoparticle-modified MXene (ZNM- MXene) into cellulose nanofiber (CNF) films. The vacuum filtering approach produces CNF@ZNM-MXene composite films with enhanced photothermal conversion efficiency, capillary hydrophilicity, and thermal localization. Because of its rapid water transport capability, excellent sunlight absorption, and efficient solar-thermal conversion under 1 kW m−2 irradiance, the CNF@ZNM-MXene solar evaporator's evaporation rate reaches 1.27 kg m−2 h−1, and the solar-vapor conversion efficiency is as high as 82.15%, outperforming most previously reported solar evaporators. Moreover, when compared to a standalone thermoelectric (TE) module, the output power of the solar thermal conversion system coupled with a CNF@ZNM-MXene composite films and a TE module is boosted by 15.32 times. This work offers a practical and effective method for simultaneously capturing solar energy and desalinating saltwater.

Experimental and numerical analysis of multi-layer micro channel applied to parabolic solar concentrator

There are numerous applications for micro-channel technology, but it has just a few applications in solar collectors. Therefore this research makes a clear contribution in this field by using a new design absorber in the concentrator, and the reflector was designed to focus the solar radiation on two sides. The solar concentrator system was attached to the tracking system to maintain the parabolic collector's perpendicularity to sun rays. This study investigates the experimental and numerical effects of the micro-channel technique on solar concentrator performance for different velocity values to meet the need for temperature differences, which gives Reynolds numbers varying from 1011 to 3273. The absorber plate was made from aluminum metal with 44 rectangular microchannels (0.3 m in length, 0.02 m in width, and 0.0009 m in height). The result indicated that the two-axis tracking system would increase output temperature by roughly 18 %. Outlet air temperature decreased significantly by 13.9 °C with changing flow rate from 0.009339 to 0.030235 kg/s. The highest efficiency was 91 % in March, 89 % in November, 80 % in February, 69.8 % in December and 65.5 % in January. A good agreement was obtained between numerical and experimental with a maximum deviation of 1.4, 1.7, 9.4 and 8.88 % for the glass cover, absorber plate, upper channel and lower channel, respectively.

Carbon and economic prices optimization of a solar-gas coupling energy system with a modified non-dominated sorting genetic algorithm considering operating sequences of water-cooled chillers

To promote the continuous operating of solar energy systems and increase the proportion of renewable energy consumption, solar devices are often integrated with conventional energy systems to reduce greenhouse gas emissions. In this study, a solar-natural gas coupling system is constructed, utilizing solar photovoltaics, thermal collectors, and high-efficiency energy conversion devices. After modelling the energy system, the operating modes are illustrated considering working sequences of water-cooled devices. A modified genetic algorithm, which incorporates reverse learning, controlled elite, and dynamic crowding distance theory, is constructed to optimize the configurations of the proposed energy system, with the aim of minimizing carbon and economic prices of the products. The performance of the energy system is compared with different algorithms and cases, and the results demonstrate that the proposed algorithm addresses the limitations of conventional methods, albeit with increased optimization times. Moreover, the proposed operating mode (Case 1) exhibits a stable performance, leading to a higher environmental and economic performance compared to conventional modes, with carbon and economic prices of 0.242 kg/kWh and 0.067 $/kWh, respectively. This study provides new insights into carbon footprints and economic performance evaluation of high-efficiency energy systems, offering valuable directions for future research in this field.