Showing papers on "Solar energy published in 2021"
TL;DR: The environmental impacts of several commercial and emerging solar energy systems at both small- and utility-scales are discussed, alongside with some technically and ecologically favorable recommendations for mitigating the impacts.
312 citations
TL;DR: In this paper, the authors present empirical and numerical analyses of thermal performance development in flat plate solar collectors (FPSCs) and provide a complete overview of the up-to-date developments, methods, critical economic factors, the significance of solar water heating, and the challenges faced by the implementations of such solar energy heating systems.
262 citations
TL;DR: In this paper, the authors provide a systematic review on the recent progresses in hybrid SDIE systems to inspire both fundamental and applied research in capitalizing the undervalued auxiliary energy sources for future integrated water, energy and environmental systems.
201 citations
TL;DR: In this article, the authors proposed an ultra-wideband (UWB) solar energy absorber composed of a Ti ring and SiO2-Si3N4-Ti thin films.
Abstract: Solar energy absorption is a very important field in photonics. The successful development of an efficient, wide-band solar absorber is an extremely powerful driver in this field. We propose an ultra-wideband (UWB) solar energy absorber composed of a Ti ring and SiO2-Si3N4-Ti thin films. In the range of 300-4000 nm, the wide band has an absorption efficiency of more than 90% and can reach 3683 nm, and it has four absorption peaks with a high absorptivity. Moreover, the weighted average absorption efficiency of the solar absorber under AM 1.5 is maintained above 97.03%, which indicates it has great potential for use in the field of solar energy absorption. Moreover, we proved that the polarization is insensitive by analyzing the absorption characteristics at arbitrary polarization angles. For both the transverse electric (TE) and transverse magnetic (TM) modes, the UWB absorption is maintained at more than 90% in the wide incidence angle range of 60°. The UWB solar energy absorber has great potential for use in a variety of applications, such as converting solar light and heat into electricity for public use and reducing the side effects of coal-fired power generation. It can also be used in information detection and infrared thermal imaging owing to its UWB characteristics.
195 citations
TL;DR: In this article, a comprehensive review highlights the recent advances in CO2 photoreduction, including critical challenges such as light-harvesting, charge separation, and activation of CO2 molecules.
Abstract: Photocatalytic production of solar fuels from CO2 is a promising strategy for addressing global environmental problems and securing future energy supplies. Although extensive research has been conducted to date, numerous impediments to realizing efficient, selective, and stable CO2 reduction have yet to be overcome. This comprehensive review highlights the recent advances in CO2 photoreduction, including critical challenges such as light-harvesting, charge separation, and the activation of CO2 molecules. We present promising strategies for enhancing the photocatalytic activities and discuss theoretical insights and equations for quantifying photocatalytic performance, which are expected to afford a fundamental understanding of CO2 photoreduction. We then provide a thorough overview of both traditional photocatalysts such as metal oxides and state-of-the-art catalysts such as metal–organic frameworks and 2D materials, followed by a discussion of the origin of carbon in CO2 photoreduction as a means to further understand the reaction mechanism. Finally, we discuss the economic viability of photocatalytic CO2 reduction before concluding the review with proposed future research directions.
165 citations
TL;DR: Wang et al. as mentioned in this paper analyzed the influence of factors on consumers' willingness to utilize solar energy for household purposes, and augmented the theoretical mechanism of the Theory of Planned Behavior by including three novel factors (perception about selfeffectiveness, belief of solar energy benefits, and perception of neighbors' participation) to comprehensively analyze the willingness of Chinese consumers.
154 citations
TL;DR: It can be concluded that the main objectives of optimizations methods are to reduce minimize investment, operation and maintenance costs and emissions to enhance the system reliability.
151 citations
TL;DR: In this paper, a dual-purpose green energy storage system with the aim of power and potable water production is proposed and investigated from the thermodynamic and economic points of view, which is based on an innovative combination of compressed air energy storage with solar heliostat and multi-effect thermal vapor compression desalination units that provides power and clean water without any emissions.
149 citations
TL;DR: All machine learning algorithms tested in this study can be used in the prediction of daily global solar radiation data with a high accuracy; however, the ANN algorithm is the best fitting algorithm among all algorithms.
Abstract: The prediction of global solar radiation for the regions is of great importance in terms of giving directions of solar energy conversion systems (design, modeling, and operation), selection of proper regions, and even future investment policies of the decision-makers. With this viewpoint, the objective of this paper is to predict daily global solar radiation data of four provinces (Kirklareli, Tokat, Nevsehir and Karaman) which have different solar radiation distribution in Turkey. In the study, four different machine learning algorithms (support vector machine (SVM), artificial neural network (ANN), kernel and nearest-neighbor (k-NN), and deep learning (DL)) are used. In the training of these algorithms, daily minimum and maximum ambient temperature, cloud cover, daily extraterrestrial solar radiation, day length and solar radiation of these provinces are used. The data is supplied from the Turkish State Meteorological Service and cover the last two years (01.01.2018–31.12.2019). To decide on the success of these algorithms, seven different statistical metrics (R2, RMSE, rRMSE, MBE, MABE, t-stat, and MAPE) are discussed in the study. The results shows that R2, MABE, and RMSE values of all algorithms are ranging from 0.855 to 0.936, from 1.870 to 2.328 MJ/m2, from 2.273 to 2.820 MJ/m2, respectively. At all cases, k-NN exhibited the worst result in terms of R2, RMSE, and MABE metrics. Of all the models, DL was the only model that exceeded the t-critic value. In conclusion, the present paper is reporting that all machine learning algorithms tested in this study can be used in the prediction of daily global solar radiation data with a high accuracy; however, the ANN algorithm is the best fitting algorithm among all algorithms. Then it is followed by DL, SVM and k-NN, respectively.
145 citations
TL;DR: The relevance of the studied models was evaluated for real-time and short-term solar energy forecasting to ensure optimized management and security requirements in this field while using an integral solution based on a single tool and an appropriate predictive model.
135 citations
TL;DR: In this article, the authors used hybrid nanofluid past an inside solar wings parabolic trough solar collector (PTSC) to rich the studies of the solar aircraft wings.
Abstract: Solar energy is the leading thermal source from the sun, with huge use of technology such as photovoltaic cells, solar power plates, photovoltaic lighting, and solar pumping water. The current effort deals with solar energy analysis and a technique to enhance solar aircraft effectiveness by using solar and nanotechnological energy. The work is based on the investigation of thermal transfer by utilizing hybrid nanofluid past an inside solar wings parabolic trough solar collector (PTSC) to rich the studies of the solar aircraft wings. The thermal source is titled solar radiative flow. For various properties such as porous media, Cattaneo Christov heat flux, viscous dissipation, play heating and thermal energy flow, the heat transfer efficiency of the wings is verified. In the case of the tangent hyperbolic fluid, the entropy generation analysis was applied. The modeled energy and momentum equations were managed using the well-established numerical plan known as the Keller box process. This paper is made up of double-different kinds of nano solid particles, Cu (copper) and ZrO2 (zirconium dioxide) in EG (ethylene glycol) as standard fluid. Various control parameters are discussed and shown in figures and tables for velocity, shear stress, temperature outlines, frictional factor, and Nusselt number. The efficiency in the aircraft wings in the case of thermal radiation amplification and variable thermal conduction parameters is seen to be improved in terms of thermal transfer. In comparison to the traditional nanofluid, hybrid nanofluid is the ideal source of heat transfer. The thermal efficiency of ZrO2–Cu/EG compared to Cu-EG decreases to a low of 2.6% and peaks to 3.6%.
TL;DR: In this article, the authors present the outlook of work conducted worldwide on the different types of concentrated photovoltaics and the effect of various performance affecting parameters, challenges, and recent progress.
TL;DR: In this article, the authors reviewed the most recently published works on plasmonic nanofluids that exclusively present its preparation methods, thermophysical properties, and applications in solar collectors.
TL;DR: In this article, the authors fit growth models to wind and solar trajectories to identify countries in which growth has already stabilized after the initial acceleration, and showed that laggards may continue to struggle to achieve high growth rates despite learning from early adopters' experience.
Abstract: Climate mitigation scenarios envision considerable growth of wind and solar power, but scholars disagree on how this growth compares with historical trends. Here we fit growth models to wind and solar trajectories to identify countries in which growth has already stabilized after the initial acceleration. National growth has followed S-curves to reach maximum annual rates of 0.8% (interquartile range of 0.6–1.1%) of the total electricity supply for onshore wind and 0.6% (0.4–0.9%) for solar. In comparison, one-half of 1.5 °C-compatible scenarios envision global growth of wind power above 1.3% and of solar power above 1.4%, while one-quarter of these scenarios envision global growth of solar above 3.3% per year. Replicating or exceeding the fastest national growth globally may be challenging because, so far, countries that introduced wind and solar power later have not achieved higher maximum growth rates, despite their generally speedier progression through the technology adoption cycle. Growth of wind and solar energy share demonstrates different dynamics between the initial phases of adoption as compared with the advanced stages. Cherp et al. study the growth dynamics of renewable energy and show that laggards may continue to struggle to achieve high growth rates despite learning from early adopters’ experience.
TL;DR: In this paper, a bi-layered structure composite for high-efficient solar evaporation based on photothermal-enhanced arginine-doped polydopamine (APDA) and raw wood, which are biodegradable and sustainable.
TL;DR: In this paper, the authors investigated three renewable energy based configurations for hydrogen production, i.e., solar PV, geothermal power generation and biomass gasification, and the results of the parametric studies and sensitivity analyses are presented and discussed.
Abstract: Hydrogen is acknowledged as a potential fuel as it can be used as an energy carrier, a storage medium, in fuel cells and as a fuel as well and offers carbon-free solutions. This paper investigates three renewable energy based configurations for hydrogen production. The renewable energy sources considered in this study are solar PV, geothermal power generation and biomass gasification. The proposed study also presents a novel configuration of biomass gasification for hydrogen production via multistage water gas shift reactors. The solar PV and geothermal energy based hydrogen production systems are analysed employing the EES software while the hydrogen production system employing biomass gasification is simulated employing Aspen Plus. All three designed configurations are proceeded through numerous parametric analyses to investigate the system behavior and effect on system efficiencies. The hydrogen production using biomass gasification technique provides with the energetic and exergetic efficiencies of 53.6% and 49.8% and the efficiencies for the geothermal power generation based hydrogen production system are found to be 10.4% and 10.2% respectively. The exergetic and energetic efficiencies of hydrogen production system employing solar PV system are found to be 17.45% and 16.95%, respectively and the system is designed to produce 1.13 mol/s of hydrogen. Furthermore, the results of the parametric studies and sensitivity analyses are presented and discussed.
TL;DR: In this article, a review of the recent progress on carbon-based materials for the development of interfacial solar vapor generation (SVG) is summarized, from artificial structures to bioinspired configurations, focusing on their structure-function relationship.
Abstract: Seawater desalination is viewed as a promising solution to world freshwater scarcity. Solar assisted desalination is proposed to overcome the high energy consumption in current desalination technologies, as it uses abundant and sustainable solar energy as the only energy input. Interfacial solar vapor generation (SVG) has attracted considerable research interest due to its high energy conversion efficiency, simple implementation, and cost-effectiveness. Among all the candidate materials for solar evaporators, carbon-based materials stand out due to their intrinsic high solar absorption, highly tunable structure, easy preparation, low cost, and earth-abundancy. In this review, the recent progress on carbon-based materials for the development of interfacial SVG is summarized. First, a brief introduction to the basic design principles of the interfacial SVG system is presented. Then, recent efforts in carbon-based solar evaporators, from artificial structures to bioinspired configurations, focusing on their structure-function relationship are highlighted. Strategies for designing antisalt-fouling desalination systems are also summarized. Last, the challenges and opportunities of carbon-based materials for solar evaporation technology are elaborated.
TL;DR: In this paper, a photoelectrochemical platform with multimediator modulation was proposed to achieve unassisted overall water splitting, where photogenerated electrons are transferred in order through multimediators driven by the electrochemical potential gradient.
Abstract: Photoelectrochemical overall water splitting has been considered as a promising approach for producing chemical energy from solar energy. Although many photoelectrochemical cells have been developed for overall water splitting by coupling two semiconductor photoelectrodes, inefficient charge transfer between the light-harvesters and electron acceptor/donor severely restricts the solar energy conversion efficiency. Inspired by natural photosynthesis, we assembled a photoelectrochemical platform with multimediator modulation to achieve unassisted overall water splitting. Photogenerated electrons are transferred in order through multimediators driven by the electrochemical potential gradient, resulting in efficient charge separation and transportation with enhanced charge transfer rate and reduced charge recombination rate. The integrated system composed of inorganic oxide-based photoanode (BiVO4) and organic polymer-based photocathode (PBDB-T:ITIC:PC71BM) with complementary light absorption, exhibits a solar-to-hydrogen conversion efficiency as high as 4.3%. This work makes a rational design possible by constructing an efficient charge-transfer chain in artificial photosynthesis systems for solar fuel production.
TL;DR: An extensive review of various solar thermal energy technologies and their industrial applications is presented in this article, where the future outlook has been proposed to overcome the challenges involved in the integration and the economics.
TL;DR: In this paper, the authors assess the dynamic impact of solar energy consumption on ecological footprints by applying quantile on quantile (QQ) regression in the context of the top ten solar energy consuming countries.
TL;DR: In this article, a comprehensive state-of-the-art review of latent thermal energy storage (LTES) technology with a particular focus on medium-high temperature phase change materials for heat recovery, storage and utilisation is provided.
TL;DR: In this article, a wind solar hybrid energy charging station was designed and optimized via HOMER software, and the optimal solution for the hybrid system consists of 44.4% wind energy and 55.6% solar energy and the annual electricity production is 843150kWh with the 0.064 $/kWh production cost.
TL;DR: In this paper, the recent progress of indoor organic photovoltaics (IOPVs) for abundant low power consumption applications is reviewed in this work, and the performance mechanism of OOPVs when the illuminance is switched from 1-sun to dim light, the research progress for indoor energy transformation and the viewpoint to speed up the development of IOPVs.
TL;DR: Spectral beam splitting (SBS) hybrid PV/T system was a promising path for utilizing the full spectrum solar energy to cogenerate electricity and high grade heat, with high conversion efficiency as discussed by the authors.
Abstract: Spectral beam splitting (SBS) hybrid PV/T system was a promising path for utilizing the full spectrum solar energy to cogenerate electricity and high-grade heat, with high conversion efficiency To settle the balance between photoelectric and photothermal conversion performance for full spectrum solar energy utilization, the sunlight based on wavelength matching was divided into two or more parts at band-gap wavelength by a spectral beam splitter: sunlight with wavelength at and close to the band-gap of PV cell was directed to generate electricity, while the sunlight with rest wavelength was used for thermal output SBS hybrid PV/T system can not only increase the overall efficiency, but can also decouple the photoelectric and photothermal conversion process in separated operation temperatures The current state-of the-art review on the advancements of SBS hybrid PV/T system performed with the aid of nanofluids, nano-film and semitransparent PV cells was presented in this work, with emphasis on the latest developments during the last decade Mechanisms of different SBS techniques, progress in system, thermodynamic and cost analyses of nanofluids, nano-film and semitransparent PV cell based SBS hybrid PV/T system were discussed in detail to give a comprehensive understanding of the nature of the full spectrum solar energy utilization and the factors impacting on the system efficiency Though the cost increase can be offset by extra energy efficiency gain, the wavelength matching, optical losses and stability of SBS hybrid PV/T system needs to be solved for future industrial application
TL;DR: In this paper, a review of the progress of solar greenhouses by investigating their integration with solar energy technologies, including photovoltaic (PV), photoltaic-thermal (PVT), and solar thermal collectors, is presented.
TL;DR: A method is proposed that optimally deployed BESSs and determined their capacity in a two-part framework to minimize solar energy curtailment, by considering network topology and power flow constraints and demonstrates that it manages to store more surplus solar power.
TL;DR: Inspired by nature, a solar absorber gel (SAG) is developed to purify water from contaminated sources using only natural sunlight as discussed by the authors, which is composed of an elastic thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) hydrogel, a photothermal polydopamine (PDA) layer, and a sodium alginate (SA) network.
Abstract: The global demand for clean and safe water will continue to grow well into the 21st century. Moving forward, the lack of access to clean water, which threatens human health and strains precious energy resources, will worsen as the climate changes. Therefore, future innovations that produce potable water from contaminated sources must be sustainable. Inspired by nature, a solar absorber gel (SAG) is developed to purify water from contaminated sources using only natural sunlight. The SAG is composed of an elastic thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) hydrogel, a photothermal polydopamine (PDA) layer, and a sodium alginate (SA) network. Production of the SAG is facile; all processing is aqueous-based and occurs at room temperature. Remarkably, the SAG can purify water from various harmful reservoirs containing small molecules, oils, metals, and pathogens, using only sunlight. The SAG relies on solar energy to drive a hydrophilic/hydrophobic phase transformation at the lower critical solution temperature. Since the purification mechanism does not require water evaporation, an energy-intensive process, the passive solar water-purification rate is the highest reported. This discovery can be transformative in the sustainable production of clean water to improve the quality of human life.
TL;DR: Preliminary guidelines for a detailed view of deep learning techniques that researchers and engineers can use to improve the solar photovoltaic plant’s modeling and planning are offered.
20 Jan 2021
TL;DR: In this article, the authors discuss the opportunities presented by salt-rejecting solar evaporation to enhance the sustainability of desalination by revisiting phase diagrams and salt crystallization physics to understand the phase transitions of water as well as the formation and growth of salt crystals.
Abstract: Summary Solar evaporation offers a promising approach to drive the distillation process, and nanotechnology may help overcome operational issues such as salt fouling. Here, we discuss the opportunities presented by salt-rejecting solar evaporation to enhance the sustainability of desalination. Within this framework, phase diagrams and salt crystallization physics are first revisited to understand the phase transitions of water as well as the formation and growth of salt crystals. We then examine salting-out and salt-free evaporating systems toward better solar desalination. The salt-rejecting techniques to be covered include subsequent flushing, self-cleaning, local crystallization, gravity-assisted cleaning, anti-clogging layer, Janus membranes, concentrating and diffusion, and gap separation. The principles of these systems are fully addressed, and the performance requirements are elaborated together with the advantages but also the limitations. Finally, the remaining challenges and future research opportunities for the further development of solar evaporation technology are highlighted.
TL;DR: A compact guide of existing model modification and novel model development regarding predicting global solar radiation, including input parameters, feature selection and model development for machine-learning models is provided.