Conversion Of Solar Radiation Research Articles

Boric acid-free electrodeposition process and solar–thermal energy conversion of and Ni-carbon black nanocomposite coatings

AbstractThis work focuses on the development of a multi-layered system, of bright nickel electrodeposited on a steel substrate, and a second layer composed of black nickel either with or without carbon black nanoparticles (CB NPs), aiming for an efficient conversion of incident solar radiation into heat, for the fabrication of solar collectors. The structural characterization, revealed that the bright nickel film was composed of metallic nickel, while the black coatings contained amorphous nickel compounds. SEM analysis unveiled the presence of pinholes on the surface of the bright nickel film, suggesting that the black nickel coating was ineffective in sealing them. The appearance of cracks with the increase in the deposition time was observed. With the nanocomposite of black nickel and CB NPs, these cracks can be avoided and the pinholes sealed. The CB NPs were found to reduce reflectance, enhancing the conversion of solar energy into heat. Graphical abstract

Celebrating Ten Years of Covalent Organic Frameworks for Solar Energy Conversion: Past, Present and Future

AbstractAccelerated anthropogenic emission of greenhouse gases due to increasing energy demands has created a negative impact on our planet. Therefore, the replacement of fossil by renewable energy resources has become of paramount interest, both societally and scientifically. It is within this setting that organic photocatalysts have emerged as a new generation of earth‐abundant catalysts for the conversion of solar radiation into chemical energy. In 2014, the first example of a covalent organic framework (COF) photocatalyst for the hydrogen evolution reaction was reported by our group, which has not only marked the beginning of COF photocatalysis for solar fuel production but also helped to accelerate research into “soft photocatalysis” based on porous polymers in general. In the last decade, significant progress has been made toward developing COFs as robust, molecularly precise platforms emulating artificial photosynthesis. This mini‐review commemorates the 10th anniversary of COF photocatalysis and gives a brief historical overview of the milestones in the field since its inception in 2014. We review milestones in the development of COFs for solar fuel production and related photocatalytic transformations, including hydrogen evolution, oxygen evolution, overall water splitting, CO2 reduction, N2 fixation, oxygen reduction, and alcohol oxidation. We discuss lessons learned for the design of structure‐property‐function relationships in COF photocatalysts, and future perspectives and challenges for the field of “soft photocatalysis” are given.

Celebrating Ten Years of Covalent Organic Frameworks for Solar Energy Conversion: Past, Present and Future.

Accelerated anthropogenic emission of greenhouse gases due to increasing energy demands has created a negative impact on our planet. Therefore, the replacement of fossil by renewable energy resources has become of paramount interest, both societally and scientifically. It is within this setting that organic photocatalysts have emerged as a new generation of earth-abundant catalysts for the conversion of solar radiation into chemical energy. In 2014, the first example of a covalent organic framework (COF) photocatalyst for the hydrogen evolution reaction was reported by our group, which has not only marked the beginning of COF photocatalysis for solar fuel production but also helped to accelerate research into "soft photocatalysis" based on porous polymers in general. In the last decade, significant progress has been made toward developing COFs as robust, molecularly precise platforms emulating artificial photosynthesis. This mini-review commemorates the 10th anniversary of COF photocatalysis and gives a brief historical overview of the milestones in the field since its inception in 2014. We review milestones in the development of COFs for solar fuel production and related photocatalytic transformations, including hydrogen evolution, oxygen evolution, overall water splitting, CO2 reduction, N2 fixation, oxygen reduction, and alcohol oxidation. We discuss lessons learned for the design of structure-property-function relationships in COF photocatalysts, and future perspectives and challenges for the field of "soft photocatalysis" are given.

Thermal energy storage behaviour of 3D ceramic/molten salt structures under real concentrated solar radiation

Molten salts, phase change materials commonly employed in thermal energy storage (TES) systems, are widely known to enhance the efficient use and storage of solar energy in concentrated solar power (CSP) plants. Here, three-dimensional TES (3DTES) have been manufactured from highly porous (up to ∼90 %) 3D printed patterned vermiculite (V) and alumina (Al2O3) supports, which have been infiltrated with molten sodium nitrate salt (nn) and solar salt (ss). These 3DTES have been validated under real concentrated solar radiation in a parabolic solar furnace. Among the different 3DTES, those based on V-nn exhibits the best efficiency for the conversion of the incident solar radiation into heat; whereas Al2O3-nn transfers the heat more efficiently and allows a faster charging-discharging cyclability due to its higher thermal conductivity. This study confirms the benefits of additive manufacturing to develop a new class of innovative TES for CSP applications.

Enhancing Solar Absorption with Double-Layered Nickel Coatings and WS2 Nanoparticles on Copper Substrates

This study focused on the development and characterization of multi-layered nickel coatings doped with WS2 nanoparticles and electrodeposited on copper substrates. To enhance the solar collector’s performance by improving the solar radiation conversion into heat, two distinct undercoatings were evaluated, along with the incorporation of WS2 nanoparticles in the black nickel layer. X-ray diffraction (XRD) analysis revealed that the bright and dull nickel undercoatings consisted of metallic nickel, whereas the black coatings comprised amorphous nickel oxide, inferred to be Ni2O3 based on energy-dispersive X-ray spectroscopy (EDS) analysis. Scanning electron microscopy (SEM) analysis of the undercoatings and black nickel morphology showed a compact surface with a relatively homogenous microstructure composed of polyhedric grains, which was free of visible cracks or pinholes. The undercoating influenced the brightness, the reflectivity and the reflectance of the black nickel films, with the dull undercoated sample showing the most promising results, with a total absorbance of 0.94. The incorporation of WS2 nanoparticles induced the formation of cracks and increased the porosity of the black nickel film. With an appropriate content of WS2 nanoparticles and the use of a dull undercoat, these drawbacks can be avoided. Concerning the integration of WS2 nanoparticles, a minor decrease in the brightness of the black films and a subsequent increase in the total absorbance ultimately led to an enhancement of the conversion of solar energy into thermal energy.

Performance enhancement attempts on the photovoltaic/thermal module and the sustainability achievements: A review

Scientists initiated a pursuit of more resilient and long-lasting energy sources due to the continuous deterioration of the environment and the substantial rise in the expense of conventional energy sources. Solar energy is one of the most cost-effective, environmentally friendly, and easily accessible sustainable energy sources. Photovoltaic/thermal (PV/T) solar modules are gaining popularity due to their ability to utilise more solar radiation to generate electric power and heat gain simultaneously. This study reviews recent advancements in PV/T modules, focusing on the dual conversion of solar radiation into electrical and thermal energy. The review highlights significant improvements, such as the use of nanoparticles, bi-fluid circulation, and innovative cooling techniques. The study examined the main categories of PV/T systems, including air-cooled, water-cooled, bi-fluid-cooled, nano-fluid-cooled, and ternary nanofluid-based units. This paper offers an in-depth analysis of various components within PV/T modules, covering aspects such as concepts, materials, and review techniques. However, challenges remain, including the trade-off between thermal and electrical efficiency and integration into existing infrastructure. Despite these limitations, PV/T systems show great potential for contributing to sustainable energy solutions and achieving global sustainable development goals. Future research directions include integrating an artificially intelligent approach for system optimization and expanding hybrid PV/T technologies.

Study of Photogalvanic Effect by using Marigold Flower as Natural Photosensitizer, Xylose as Reductant and Tween 80 as Surfactant for Solar Radiation Conversion and Storage

Objective: A study work plan has been put up for methodical work in the field of solar energy Photogalvanic (PG) cells. It was suggested and required to do experiments with PG cells in sunlight conditions. Improving the conversion of solar energy into electricity and storing it in PG cells is the goal of our study. Method: An H-shaped glass tube with two arms was manufactured using the specially developed PG (Figure 1) cell. Many characteristics of a PG cell with an MG+D-Xylose+Tween-80 system was investigated. Findings: The open circuit voltage, voltage at dark, photopotential (PP), and photocurrent (PC) recorded in this investigation are 1080.00 mV, 165.00 mV, 915.00 mV, and 674.00 µA, respectively. The Fill Factor (FF) and Conversion Efficiency (CE) that were observed 1.891% and 0.2732, respectively. Novelty: Through the adjustment of PG cells' numerous parameters, the effects of solar energy were investigated. Based on the aforementioned results, PG systems have demonstrated through experimentation that they are an effective system and should be further investigated, particularly with regard to improving solar energy output and storage. Keywords: D-Xylose, Tween - 80, Marigold, Photocurrent, Natural dye

Cost-efficient sunlight-driven thermoelectric electrolysis over Mo-doped Ni5P4 nanosheets for highly efficient alkaline water/seawater splitting

Thermoelectric water spitting to hydrogen systems has great potential in the production of environment-friendly fuel using renewable solar energy in the future. In this work, we prepared porous nanosheet Mo doping Ni5P4 catalysts on nickel foam with efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance in alkaline media. Density Functional Theory (DFT) calculations and experimental studies have shown that Mo doping deadeneds the interaction between H and O atomic orbitals of transition state water molecules, effectively weakening the activation energy of H2O dissociation. Therefore, Mo doping is favorable for enhancing HER activity with overpotential at 10 mA cm–2 of 93 mV and Tafel slope of 40.1 mV dec–1 in 1 M KOH. Besides, it exhibits high alkaline OER activity with an ultra-low overpotential of 200 mV at 10 mA cm–2. Moreover, this catalyst only needs 1.537 V in a dual-electrode configuration of the electrolytic cell, which is much lower than the commercial Pt/C-RuO2 couple (1.614 V). In addition, we have developed and constructed a solar thermoelectric generator (TEG) that is capable of floating on water. This TEG has a continuous power output and an exceptionally long lifespan, providing a stable power supply to the synthesized catalyst electrolyzer. It can produce a maximum power output of over 90 mW, meeting the requirement of converting solar radiation heat into usable electricity. As a result, the system achieves productivity of 0.11 mL min–1 H2. This solar thermal energy conversion technology shows the possibility of large-scale industrial production of H2 and provides a new idea for exploring heat source utilization.

Impact of absorber surface coatings on the thermal performance of non-concentrating solar thermal collectors: An overview

In this critical evaluation, the impact of absorber surface coating on the thermal efficiency (%) of non-concentrating solar thermal collectors (STCs) is examined and discussed. Absorber surface coatings enable an almost instantaneous conversion of solar radiation into heat. To achieve high sunlight absorption capacity and low solar emittance, several types of selective solar coatings are continually being developed. This review article offers a novel aspect based on extensive research that has been published in the past related to the impact of absorber surface coating on the thermal performance of non-concentrating STCs. The article demonstrates the commonalities in the results by thoroughly evaluating all the coating types that have the potential to influence STC's performance. An exhaustive examination of the available research from several studies shows that absorber surface coating enhances the STC absorber's capacity to absorb heat.

Efficiency of Heating and Evaporation of Graphene Nanofluid under Solar Radiation

The conversion of solar radiation into steam is a crucial focus in today’s green energy, ecology, and clean water production. This study presents the first investigation of the heating and evaporation process of a rotating graphene nanofluid under the influence of solar simulator radiation. The study examined the influence of various factors on the heating and evaporation process of the graphene nanofluid, including the direction of irradiation, graphene concentration and rotation speed. It was demonstrated that the evaporation rate strongly depends on the graphene concentration and the irradiation method of the samples. The heating characteristics of graphene also depend on the irradiation method. It was shown that graphene heated to a higher temperature when in direct contact with radiation, while graphene within the bulk volume was heated less effectively than the base liquid. Moreover, the application of rotating graphene nanofluid in this research was found to enhance thermal efficiency by 2.5% compared to distilled water, with a graphene volume concentration of 0.1%. Consequently, various effects of the rotating graphene nanofluid volume on hydrodynamic, heat, and mass transfer parameters were identified, which hold significance for both fundamental and applied tasks in energy, chemical technology, and ecology.

Technical achievable potential of photovoltaic conversion of solar radiation for the conditions of Ukraine

This study investigates solar energy photovoltaic conversion processes while exploring new approaches to identify potential areas for the installation of photovoltaic stations. This research aims to enhance existing methodologies of technical-achievable potential calculation, considering the specificity of territories, the possibility of installing rooftop photovoltaic stations, and the current development of photovoltaic technologies. The developed methodology considers the type of stations, urban building specifics during the calculation of suitable areas for photovoltaic station installation, the potential for installing small and medium rooftop stations, and the modern technical characteristics of photovoltaic modules. The refinement of the PV panels and PV station area ratio calculations revealed that its value depends on the type and power of the station, varying from 0 to 1. This approach simplifies the determination of power capacity of a station that can be installed in a designated area. Consideration of the technical characteristics of the latest photoelectric conversion technologies demonstrates a significant potential increase compared to the existing calculation methodologies. Calculations conducted using the developed methodology revealed that the technically achievable potential of solar energy conversion for Ukraine is 369 TWh/year (254 GWp DC). This figure exceeds the estimations of existing calculation methodologies at least twice. The obtained results showed a significantly greater potential for solar energy in Ukraine, which expands the possibilities of using photovoltaic technologies to supply energy to consumers. This is especially important during the war because of the insufficient electricity production by existing power plants, many of which have been destroyed.

On the Efficiency of Solar Radiation Conversion into Steam, Production of Clean Water, and Generation of Electrical Energy

This study focuses on the development of a model for evaluating the efficiency of converting solar radiation into thermal energy. The efficiency coefficient is represented as a function of multiple variables, including system geometry, time, properties of the working fluid, and external parameters. The developed model is a simplified version and is applicable to systems with a stationary working fluid undergoing heating and vaporization due to solar radiation. Calculations were performed based on the model using a gold-water nanofluid. The results of the calculations demonstrated the existence of an optimal range of optical thickness and nanoparticle concentration, where the working fluid is effectively heated and vaporized. It is shown that the efficiency of systems employing nanofluids as heat transfer fluids cannot be evaluated solely based on the absolute value of the heating efficiency coefficient. However, it can be assessed through its derivative with respect to time. The faster the heating efficiency coefficient decreases over time, the more efficient the system is in terms of heating, and the sooner it reaches a steady-state condition. The developed model serves as a foundation for the advancement of more sophisticated models that allow for the evaluation of various other factors, such as complex geometries with forced fluid flow, the nature of interactions between nanoparticles and the base fluid, as well as mechanisms of solar radiation conversion into thermal energy.

Passive Energy Conservation Strategies for Mitigating Energy Consumption and Reducing CO2 Emissions in Traditional Dwellings of Peking Area, China

Within China, brick dwellings stand as archetypal relics of traditional habitation, embodying a “living fossil” status. The sustainability of these dwellings is contingent upon the integration of energy-conservation strategies. This study scrutinized and empirically assessed a representative dwelling in the Peking area. Using numerical simulations, the impact on energy consumption of factors such as insulation and glazing type, external wall thickness, insulation thickness, and solar energy utilization was evaluated. The outcomes reveal that introducing external thermal insulation—specifically, expanded polystyrene panels with a thickness of 60 mm and 40 mm for the roof and exterior walls, respectively—along with a sunspace of depth 1.5 m yielded superior energy efficiency. Additionally, substituting conventional roofing with solar tiles exhibited a potential annual electricity generation coupled with an annual solar radiation conversion efficiency of 17%. Collectively, these strategies induced a substantial reduction in annual energy consumption. This study presents tailored energy-conservation measures and provides design decision support for architects’ practical recommendations on thermal environment control of passive traditional dwellings in the Peking area.

Solar Energy and Climate Change

Modern solar energy is based on photothermal, photovoltaic and hybrid solar radiation conversion and passive capture of solar radiation. Photothermal conversion of solar radiation takes place in low-temperature, medium-temperature, and high-temperature photoconversion systems. Flat collectors with water and air are used for low-temperature conversion of solar radiation. Solar concentrators are used for medium-temperature conversion of solar radiation. Concentrators with heliostatic fields and parabolic reflectors of solar radiation are used for hightemperature conversion of solar radiation. Solar cells made of different materials are utilized for the photovoltaic conversion of solar radiation. Stand-alone and photovoltaic systems connected to the electricity distribution network are used to supply consumers with electricity. Fixed tilt, single or dual-axis tracking solar power plants are designed with the aim to generate a larger amount of electricity. Hybrid solar collectors are used for the simultaneous conversion of solar radiation into heat and electricity. For passive capture of solar radiation, individual residential and other buildings are used, which are built in accordance with the principles of solar architecture. Solar energy uses mainly environment-friendly materials, except toxic As and Cd in GaAs and CdTe solar cells. Devices used in solar energy do not emit harmful substances and do not have an adversary impact on climate change.

Entropy analysis on EMHD 3D micropolar tri-hybrid nanofluid flow of solar radiative slendering sheet by a machine learning algorithm

The purpose of this paper is to analyze the heat transfer behavior of the electromagnetic 3D micropolar tri-hybrid nanofluid flow of a solar radiative slendering sheet with non-Fourier heat flux model. The conversion of solar radiation into thermal energy is an area of significant interest as the demand for renewable heat and power continues to grow. Due to their enhanced ability to promote heat transmission, nanofluids can significantly contribute to enhancing the efficiency of solar-thermal systems. The combination of silicon oil-based silicon (Si), magnesium oxide (MgO), and titanium (Ti) nanofluids has attracted attention for their ability to improve the performance of solar-thermal systems. The present study discloses a new approach for intelligent numerical computing solving, which utilizes an MLP feed-forward back-propagation ANN and the Levenberg-Marquard algorithm. The collection of data was conducted for the purpose of testing, certifying, and training the ANN model. The Bvp4c solver in MATLAB is utilized to solve the nonlinear equations governing the momentum, temperature, skin-friction coefficient, and Nusselt number. The characteristics of numerous dimensionless parameters such as porosity parameter left(K={0.0,2.0,4.0}right), vortex viscosity parameter left({R}_{1}={0.5,1.0,1.5}right), electric field parameter left(E={0.0,0.1,0.2}right), thermal relaxation time left(Lambda ={0.01,0.10,0.20}right), heat source/sink parameter, left(Q=-{0.3,0.0,0.3}right) thermal radiation parameter left(R={0.5,1}.{0,1.5}right), temperature ratio parameter left({theta }_{w}={0.5,1.0,1.5}right),nanoparticle volume fraction left(phi ={0.00,0.02,0.04}right) on Si + MgO + Ti/silicon oil micropolar tri-hybrid nanofluida are analyzed. The ANN model engages in a process of data selection, network construction, training, and evaluation of its effectiveness through the utilization of mean square error. Tables and graphs are used to show how essential parameters affect fluid transport properties. The velocity profile is decreased by higher values of the porosity parameter, whereas the temperature profile is increased. The temperature profile is inversely proportional to higher values of the electric field parameter. The micro-rotation profiles reduced by expanding values vortex viscosity parameter. It has been determined that entropy generation and Bejan number intensifications for enlarged nanoparticle volume fraction.

Thermal conversion of solar radiation for possible applications in industrial heat convertors

The proposed solar thermal absorber consists of sandwich structure-inspired Ti–SiO2–Ti (Titanium–Silicon Dioxide -Titanium) Metal-insulator-Metal (MIM) material. Here proposed thermal absorber has materials, Ti as ground, SiO2 as substrate and Ti as resonator. The design of solar thermal absorber is well-versed with the modern theory of absorption and made up on a nanometre basis with each parameter being less than 500 nm. An average absorption of 96.34 % has been achieved throughout the wavelength range of 0.2–3 μm including various regions including UV, Visible, NIR, and MIR with an average absorptance 92.72 %, 93.81 %, 96.58 %, 98.55 % respectively. The proposed nanoscale solar absorber also has 1920 nm of wavelength range above 95 % with an average absorptance of 97.985 % and 2730 nm of wavelength range above 90%with an average absorptance of 96.6 %, although transverse electric (TE) and magnetic (TM) modes achieved an average absorptance of 96.34 % and 94.1 % respectively. We also have noticed characteristics like large angular and polarization-independent in the proposed solar energy absorber structure which eventually benefitted the applications of optoelectronics.

Artificial neural network model of non-Darcy MHD Sutterby hybrid nanofluid flow over a curved permeable surface: Solar energy applications

The conversion of solar radiation to thermal energy has recently much interest as the requirement for renewable heat and power grows. Due to their enhanced ability to promote heat transmission, nanofluids can significantly improve solar-thermal systems' efficiency. This section aims to study the heat transfer behavior of the Sutterby hybrid nanofluid flow of magnetohydrodynamics in the presence of a non-uniform heat source/sink and linear thermal radiation over a non-Darcy curved permeable surface. A novel implementation of an intelligent numerical computing solver based on multi-layer perceptron (MLP) feed-forward back-propagation artificial neural network (ANN) with the Levenberg-Marquard algorithm is provided in the current study. Data were gathered for the ANN model's testing, certification, and training. Established mathematical equations are nonlinear, which are resolved for velocity, the temperature in addition to the skin friction coefficient, and the rate of heat transfer by using the bvp4c with MATLAB solver. The ANN model selects data, constructs and trains a network, then evaluates its efficacy via mean square error. Graphs illustrate the impact of a wide range of physical factors on variables, including pressure, velocity, and temperature. In the entire study, the thermal energy improved by the SiO2 (silicon dioxide) - Au (gold) hybrid nanofluid than the SiO2-TiO2 (titanium dioxide) hybrid nanofluid. The higher internal heat generation/absorption parameter values increase the temperature.

Complex Positioning System for the Control and Visualization of Photovoltaic Systems

This paper presents a proposal of a complex mechatronic system that enhances the effectivity of obtaining energy from renewable resources. The main focus is on the photovoltaic energy system, which obtains electricity from the conversion of solar radiation through photovoltaic crystalline silicon-based panels. The design of the complex mechatronic system consists of several steps. The structural design of the photovoltaic panel positioning unit in the form of a three-dimensional model is made in the selected modelling programming environment. Subsequently, a propulsion system is proposed for the designed structure, the functionality of which is verified in the programming environment Automated Dynamic Analysis of Mechanical Systems. The control system design using a programmable logical controller is also presented. The corresponding control algorithm is designed in the programming environment Step7 and covers the optimal positioning of photovoltaic panels. The developed application in the WinCC environment provides a visualization of the positioning control process. The conclusion is devoted to the assessment of the obtained results for the proposed complex mechatronic system for photovoltaic panel positioning in comparison with photovoltaic panels in fixed installation. The presented results were obtained by simulations.

Laser Synthesis and Optical Properties of Hybrid Silicon Nanostructures for Photothermal Conversion of Solar Radiation

Laser Synthesis and Optical Properties of Hybrid Silicon Nanostructures for Photothermal Conversion of Solar Radiation

Experimental investigations of the microscale concentrated photovoltaic/thermal system based on a solar parabolic trough concentrator

The world’s electricity generation from photovoltaic systems has been growing significantly for the last two decades. Nowadays, one of the most interesting trends in the conversion of solar radiation is the use of concentrating solar power collectors. Among other well-known technologies, quite a new solution is concentrated photovoltaic thermal installations, which use photovoltaic panels as a power converter. This paper presents the experimental works carried out on the prototypical micro-scale parabolic-through solar concentrator equipped with monocrystalline silicon solar cells located on the hexagonal receiver tube. The main goal of these investigations was to determine the possibility of enhancing the efficiency of photovoltaic solar cells by placing them under concentrated solar radiation. Obtained results showed, that the maximum power of tested solar cells increased approx. 29% from 14.40 ±0.50We to 18.60 ±0.60We using concentrated sunlight in comparison to efficiency measured in direct sunlight. It was demonstrated that the use of solar radiation concentrators is justified in the case of solar installations, even with low concentration ratio factors.