Hybrid Solar Collector Research Articles

Experimental Comparison of Glazed and Unglazed Hybrid Solar Modules Considering Power Productivity and Cell Temperature

AbstractThis study presents the effect of cell temperature on the hybrid solar collectors PV/T for modules with and without using a front glass cover. A numerical model of thermal behaviour was carried out for glazed (PV/Tg ) and unglazed (PV/Tun) modules. As a result of this experimental investigation conducted for presented PV/T modules, a sufficient decrease in the cell temperature of PV/Tun compared to the PV/Tg, PV/Tun module exceeded the PV/Tg by 19%. Thus, the electrical productivity of the PV/Tun module was higher; it was 3.44% higher than the PV/Tg value. The outlet liquid temperature of the un-covered module was 6.34% higher than the outlet liquid temperature of the glass-covered module. Besides, the total efficiency of the PV/Tg was higher during the periods of study. In this sense, the glass-covered module is preferable for applications that deal with overall efficiency as a desirable factor. The un-covered module is much beneficial for applications that need high electrical productivity.

Optimizing hybrid solar collector efficiency with MgO/CNT nanofluid: a response surface methodology investigation

Optimizing hybrid solar collector efficiency with MgO/CNT nanofluid: a response surface methodology investigation

Energy-efficient solar heat supply system based on hybrid photovoltaic collector

Following the commitments made under the Paris Climate Agreement, the scientific community has initiated a strategic increase in the share of renewable energy sources while gradually reducing dependence on traditional carbon fuels. Priority is given to the acceleration of the development of the photovoltaic industry, which has shown a constant increase in capacity over the past decades. According to the energy and climate strategies of the European Union, a significant increase in the amount of energy generation due to solar sources is planned. Therefore, the article is devoted to the development of a solar heat supply system based on a hybrid thermal photovoltaic solar collector with an improved design and analysis of the main characteristics of its operation using computer modeling. The authors have developed a 3D computer model of the proposed hybrid system with a solar collector by using SolidWorks software. The change in the temperature of the heat carrier in the hybrid thermal photovoltaic solar collector under constant solar radiation was analyzed. The temperature change of the coolant in the thermal accumulator of the system was also investigated. The results of the simulation of thermal processes revealed the key regularities of the temperature increase during the computer experiment, both in the hybrid thermal photovoltaic solar collector and in the thermal accumulator. The change in the instantaneous specific heat capacity of the developed solar collector was analyzed, and its average efficiency was estimated. The trends of changes in the thermal efficiency of the developed heat supply system during the computer experiment were determined. The novelty of the study is that the design of the hybrid thermophotoelectric solar collector has been improved, its 3D computer model has been developed, and the main thermal characteristics of the developed heat supply system with constant solar radiation have been obtained, which will contribute to the development of calculation methods for such heat supply systems with hybrid solar collectors in the future.

INVESTIGATION OF STABILITY OF TiO2-BASED NANOFLUIDS FOR POTENTIAL USE IN HYBRID SOLAR COLLECTORS

The use of nanofluids in the cooling system of hybrid solar collectors is an urgent task of intensification of heat transfer. This heat carrier allows for more efficient cooling of the surface of the solar panel, which increases the productivity of the collector. However, the low stability of the nanofluid, manifested in the agglomeration of nanoparticles and their subsequent precipitation, affects the deterioration of the thermophysical properties. This article discusses the sedimentation process of TiO2-double distilled water nanofluid stabilized with CTAB and SDBS surfactants. The sedimentation process was monitored by UV-vis spectroscopy. A high stabilizing effect was observed with the use of CTAB surfactant, expressed in a low sedimentation rate compared to use of SDBS.

Development of a combined system with a hybrid solar collector and determination of its thermal characteristics

The object of the study: a system with a photovoltaic thermal hybrid solar collector. The main problem addressed is to enhance the conversion and utilization efficiency of solar energy by developing a new design of photovoltaic thermal hybrid solar collector. A computer model of the proposed design of a photovoltaic thermal hybrid solar collector (PVT) was developed, and its thermotechnical characteristics were investigated. Patterns of temperature changes in the heat transfer fluid in PVT and thermal accumulator over time of irradiation were determined. It is shown that the instantaneous thermal power of the solar collector was 540 W/m2, and the efficiency was 0.6. Changes in the instantaneous specific thermal power of the system with PVT (up to 450 W/m2) and its efficiency in heat accumulation in the accumulator (0.5) were studied. The high efficiency of PVT can be explained by its optimal design, which ensures simultaneous production of thermal and electrical energy, as well as balancing of the operation of the thermal and photovoltaic parts. The main difference between the developed model and existing analogs is the comprehensive consideration of the interaction of the thermal and photovoltaic parts in one installation. The model allows optimizing the PVT design to increase its efficiency. The research has allowed developing a new design of a photovoltaic thermal hybrid solar collector, which ensures high efficiency of conversion and utilization of solar energy. The obtained results and the developed model provide a basis for further improvement of PVT and its implementation in power systems of buildings and technological processes to increase the share of solar energy utilization and reduce fossil fuel consumption

Studies on hybrid solar collector with water driven solar tracking unit

ABSTRACT The current solar concentrating collectors can be driven by water gravity without using a torque motor. It saves the electricity required to drive the large solar concentrating collectors. The objective of this study is to simulate and experimentally evaluate a novel hybrid system that combines photovoltaic and thermal technology with a hydro-powered solar tracking unit. The device consists of a hybrid solar collector, which is a multi-reflector compound parabolic collector (MRCPC), an evacuated tube receiver, photovoltaic (PV) panels, and a tracking system. The tracking mechanism attaches the tracking weights to both sides of a chain and sprocket. This hybrid collector rotates around its axis by adjusting the weight of the water in each of the monitoring weights. The system integrates a 12-volt direct current pump (operated by photovoltaic power) for tracking, with flow rate control. A mathematical model is developed and applied to determine the ideal tilt angle for a solar concentrating collector. The model was then used to compare the actual tilt angle and minimize errors in tracking. An experimental investigation used a flow rate of 0.8 LPM. The study achieved a mean tracking error of 2.05º, a maximum thermal efficiency of 43.65%, a maximum solar PV efficiency of 11.30%, and a maximum overall efficiency of 29.81%. An analytical method was developed to simulate the collector’s outlet temperature.

Development of Low-Cost c-Si-Based CPV Cells for a Solar Co-Generation Absorber in a Parabolic Trough Collector

Concentrator photovoltaics (CPVs) have demonstrated high electrical efficiencies and technological potential, especially when deployed in CPV–thermal (CPV-T) hybrid absorbers, in which the cells’ waste heat can be used to power industrial processes. However, the high cost of tracking systems and the predominant use of expensive multi-junction PV cells have caused the market of solar co-generation technologies to stall. This paper describes the development and testing of a low-cost alternative CPV cell based on crystalline silicone (c-Si) for use in a novel injection-molded parabolic hybrid solar collector, generating both, photovoltaic electricity and thermal power. The study covers two different c-Si cell technologies, namely, passive emitter rear contact (PERC) and aluminum back surface field (Al-BSF). Simulation design and manufacturing are described with special attention to fingerprinting in order to achieve high current carrying capacities for concentrated sunlight. It was determined that Al-BSF cells offer higher efficiencies than PERC for the considered use case. Solar simulator tests showed that the highly doped 4 cm2 cells (50 ohm/sq) reach efficiencies of 16.9% under 1 sun and 13.1% under 60 suns at 25 °C with a temperature coefficient of −0.069%(Abs)/K. Finally, options to further improve the cells are discussed and an outlook is given for deployment in a field-testing prototype.

Optimizing Nanofluid Hybrid Solar Collectors through Artificial Intelligence Models

This study systematically explores and compares the performance of various artificial-intelligence (AI)-based models to predict the electrical and thermal efficiency of photovoltaic–thermal systems (PVTs) cooled by nanofluids. Employing extreme gradient boosting (XGB), extra tree regression (ETR), and k-nearest-neighbor (KNN) regression models, their accuracy is quantitatively evaluated, and their effectiveness measured. The results demonstrate that both XGB and ETR models consistently outperform KNN in accurately predicting both electrical and thermal efficiency. Specifically, the XGB model achieves remarkable correlation coefficient (R2) values of approximately 0.99999, signifying its superior predictive capabilities. Notably, the XGB model exhibits a slightly superior performance compared to ETR in estimating electrical efficiency. Furthermore, when predicting thermal efficiency, both XGB and ETR models demonstrate excellence, with the XGB model showing a slight edge based on R2 values. Validation against new data points reveals outstanding predictive performance, with the XGB model attaining R2 values of 0.99997 for electrical efficiency and 0.99995 for thermal efficiency. These quantitative findings underscore the accuracy and reliability of the XGB and ETR models in predicting the electrical and thermal efficiency of PVT systems when cooled by nanofluids. The study’s implications are significant for PVT system designers and industry professionals, as the incorporation of AI-based models offers improved accuracy, faster prediction times, and the ability to handle large datasets. The models presented in this study contribute to system optimization, performance evaluation, and decision-making in the field. Additionally, robust validation against new data enhances the credibility of these models, advancing the overall understanding and applicability of AI in PVT systems.

Analysis of the energy efficiency of a system with a hybrid solar collector and thermal energy storage

The object of research is heat transfer in a hybrid thermal photovoltaic solar collector. International agreements and strategies aimed at combating climate change and reducing greenhouse gas emissions strongly call for the active implementation of renewable energy sources on a global scale. A special emphasis is placed on the development of solar energy, which has significant growth potential due to the constant improvement of technologies and cost reduction of production. With this in mind, the authors focused on the development and analysis of a computer model of an innovative hybrid system that effectively combines a solar collector for the simultaneous production of both thermal and electrical energy. The research included a detailed study of the temperature changes of the heat carrier in the hybrid photovoltaic solar collector and thermal accumulator during the period of solar irradiation. Thanks to careful monitoring, the main patterns of gradual temperature increase in both key components of the hybrid system were established. In addition, an assessment of the dynamics of changes in the instantaneous thermal power of the solar collector under the influence of various factors, such as the intensity of solar radiation, the angle of inclination of the collector, wind speed, etc., was carried out. The results of computer modeling showed the average indicator of the efficiency of the entire hybrid system, as well as its variations during a certain time of operation. In addition, the change in the instantaneous specific heat capacity and the overall efficiency of heat energy generation by the hybrid photovoltaic solar collector were analyzed. Special attention was paid to the study of the dynamics of changes in the thermal efficiency of the entire system, as well as its ability to efficiently store thermal energy in a specialized battery. The comprehensive analysis made it possible to obtain the key thermophysical parameters of the developed hybrid system with a photovoltaic solar collector. This data is extremely important, as it will allow engineers and scientists to accurately calculate the potential performance and efficiency of such a system when it is put into practical use in the future. In general, the results of the study emphasize the promising development of hybrid solar collectors as one of the leading technologies in the field of renewable energy in the context of global challenges of climate change.

INFLUENCE OF A TWO-STAGE HEAT RECOVERY SCHEME ON THE OPERATION OF THE PV-MD COLLECTOR

Production efficiency of the electric power the solar module is essentially defined by a thermal operating mode. One of progressive ways of affecting on a thermal regime is vapour cooling which at distillation of saliferous waters gives the chance to operate temperature of the solar cell and to gain a by-product in the form of sweet water. At cascade multistage recoveryevaporation heats samplingof the circuit solution of a process of cooling allows to optimise a combination of electric and distillation productivity of the photomodule. The analysis of formation of temperature pattern of an absorber of a hybrid solar collecting channel (PV-MD), a salt solution chilled at two-level distillation with recoverywarmth of steam is in-process carried out. The analysis method allows to investigate PV-MD-collecting channel characteristics - temperatures of an absorber and heat-transfer agent, productivity of system on the electric power and distillate at implementation of counter flow and direct-flow circuit designs of traffic of a solution, and also depending on module working conditions. The work purpose - synthesis of a method of calculation of opeating characteristics of a hybrid solar collecting channel with the finestiller at the cascade way Heat and mass transfer heat-transfer agent and revealing of the rational technological circuit design of the device. The mathematical model of a hybrid solar collecting channel is characterised by possibility of the local analysis of processes Heat and mass transfer for real conditions of a solar and climatic situation. The analysis Heat and mass transfer in alternative conditions showed that sampling of the circuit design of traffic of heat-transfer agent practically does not depend on electric power conditions of production, but is essentially defined by agency of directions of streams of heat-transfer agent on distillation process. On conditions of rationalisation of process of distillation for achievement of the greatest level of production of distillate the circuit design of direct-flow cascade traffic of a solution is effective. Keywords: hybrid solar collector, method PV-MD, temperature regime, distillate production, electricity production

Efficiency of Hybrid Solar Collectors Application in Building Heating Systems

The article focuses on the use of hybrid solar collectors as one of the ways to increase the efficiency of solar systems in general. The authors consider the design of a solar collector with the arrangement of circulation pipes above the heat-absorbing surface with a transparent coating. A solar system with natural circulation of the heat carrier (water) has been investigated. Based on the research results, a nomogram has been developed to define the relationship between the thermal efficiency coefficient of the solar cover with a transparent coating and the arrangement of pipes of the heat carrier circulation loop above the heat absorber depending on the angles and the intensity of the radiation flux. As a result, a functional dependence is obtained, which allows accurately determining the coefficient of thermal efficiency for specific parameters and input data. This research indicates the need for the use of hybrid solar collectors to ensure efficient collection of solar energy and emphasizes the importance of further research and improvement of the design of elements of such systems to reduce environmental pollution and increase the stability of heating systems.

BUILDING HEAT SUPPLY SYSTEM BASED ON HYBRID SOLAR COLLECTORS

Increasing the efficiency of solar heat supply systems is one of the important problems of solar energy. The research presented in this article is aimed at improving the efficiency of hybrid solar collectors without a transparent coating for building heating systems. One of the key challenges in the field of solar energy is the development of new technologies to ensure high collection of solar energy and to integrate it into traditional heating and hot water systems. The study shows that hybrid solar collectors with the placement of heat carrier circulation circuit tubes above the heat absorber can increase the thermal efficiency factor with a certain change in the angle of inclination and the density of solar radiation. A nomogram was also developed that determines the dependence of this coefficient on the angles of arrival of solar radiation and its density.

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.

Perfect stabilisation of the electrical efficiency of a set of semi-transparent photovoltaic panels using a smart cooling system

The hybrid solar photovoltaic systems are among the most widely used photovoltaic systems due to their high electrical efficiency. In this paper, a set of smart hybrid photovoltaic systems, integrating a semi-transparent photovoltaic panel with smart hybrid solar collector tubes is proposed. Additionally, a smart cooling system is used for the first time to perfectly stabilize the electrical efficiency of the proposed hybrid systems for different solar irradiation. These new systems are mainly proposed for the first time to improve the electrical efficiency of a semi-transparent photovoltaic panel. To obtain the effects of sun irradiation and linear Fresnel lens on the performance of each hybrid system, a set of mathematical equations is coded in MATLAB software. The main results revealed that the maximum electrical efficiency of the SPV/SHC/Bi2Te3, SPV/SHC/PbTe, SPV/SHC/Bi2Te3/Bi2Te3, SPV/SHC/Bi2Te3/PbTe, and SPV/SHC/PbTe/PbTe in absence of smart cooling system are respectively 2.88%, 3%, 5.76%, 5.88%, and 6% higher than that of the stand-alone SPV system. When these hybrid panels are equipped with smart cooling system, the maximum electrical efficiency of the SPV/SHC/Bi2Te3, SPV/SHC/PbTe, SPV/SHC/Bi2Te3/Bi2Te3, SPV/SHC/Bi2Te3/PbTe and SPV/SHC/PbTe/PbTe are respectively 3.58%, 3.7%, 6.46%, 6.58% and 6.7% higher than that of the conventional SPV system. These results also showed that the SPV/SHC/PbTe/PbTe system with smart cooling system is electrically more efficient than the other systems, which is due to its higher efficiency and power output of 14.1% and 410.271 W. The electrical efficiency of the proposed hybrid systems, equipped with an intelligent cooling system, stays stable for higher and medium values of sun irradiation. These results provide a definitive solution to the problem of decreasing electrical efficiency of photovoltaic panels due to the increase of its temperature.

Sustainability contribution of hybrid solar collector towards net-zero energy buildings concerning solar cells wasted heat

Sustainable communities require emerging innovations to fulfill the energy needs of urban societies. Renewable energy systems are the most significant trend in net-zero energy buildings (NZEBs) that serve sustainable development. Due to their consistent power generation, standalone hybrid solar photovoltaic/thermal (PV/T) systems are currently in reasonable demand in the building sector. This study adopted a special design of the hybrid solar collector utilising a combination of water and air simultaneously as a working fluid (combi-PV/T), considering the waste heat generated from classical polycrystalline photovoltaic (PV) modules that negatively affect the building's sustainability. The main comparison parameters considered between the examined combi-PV/T and PV modules are the waste heat, solar cell surface temperature, exergy efficiency, and sustainability index. The experimental result confirmed the effectiveness of the combi-PV/T compared to the classical PV module. The results showed that the waste heat generated by the combi-PV/T module was lowered by 77.6 %. Besides, the average solar cell surface temperature of the PV module decreased by 30.6 % in the combi-PV/T module from 53.6 °C to 36.4 °C. Exergy efficiencies for combi-PV/T and PV ranged from 12.6 to 35.3 % and 4.4–6.8 %, respectively. Moreover, the sustainability index values were in the range of 1.15–1.8 and 1.03–1.06, respectively. Obtained findings indicated that the combination of hybrid solar PV/T systems has an efficient sustainability contribution and the potential to subsidise sustainable building construction towards NZEBs.

Enhancing the overall performance of the hybrid solar photovoltaic collector by open water cycle jet-cooling

In this paper, the electrical and thermal performance of hybrid photovoltaic (PV/T) system works with an active cooling open water cycle has been improved. Experimental tests were conducted on the (PV/T) of two cases (with and without reflectors) and the reference photovoltaic (PV) in Iraq - Samarra located at latitude (34.26°N) and longitude (43.89 °C). Several experiments were carried out during June 2021 with a (0.014 kg/s) mass flow rate. Results manifested that the maximum daily electrical, thermal and overall PV/T collector efficiency with reflectors were 10.2%, 82.3%, 92.5%, respectively, with the highest improvement in the electrical power (EP) of 69.4%. This technique has proven its effectiveness in the hot climate that Iraq enjoys (suffers), and that the water jets played their role in decreasing the temperature of the hybrid panel despite the increase in the concentration of solar radiation throughout the presence of reflectors.

TecSB: An Open Web Tool of Energy Efficiency and Solar Energy Integration in Mexican Buildings

There is a need for stakeholders in the construction sector to evaluate energy efficiency and renewable energy generation alternatives appliable to buildings at early design stages. In this regard, public and private organizations have developed tools to compare different options. It was observed that when the objective was to create nearly Zero Energy Buildings (nZEB), the number of tools was still scarce. With this aim, this work presents a new, free digital tool that can predict, among others, energy consumption, energy generation, emissions savings, and payback time. For this purpose, different alternatives applicable to the roof, such as phase change material (PCM), insulation, and reflective paint, as well as to window-to-wall ratios (WWR), with four different glass technologies, can be evaluated. Furthermore, four renewable energy systems were available for comparison: the solar thermal collector (ST), photovoltaic (PV), flat hybrid solar collector (PVT), and low-concentration parabolic solar collector (LCPVT). Our tool was developed based on the results of transient dynamic building simulations of both residential and non-residential building models located in the hot semi-arid conditions of Monterrey, Mexico. Among the results, the small impact of using only reflective paint, the need to combine PCM with insulating material to obtain the best energy savings, and the large impact on emissions savings when using an LCPVT stand out.

Energetic and parametric studies of a basic hybrid collector (PV/T-Air) and a photovoltaic (PV) module for building applications: Performance analysis under El Jadida weather conditions

The photovoltaic thermal hybrid collectors represent one of the most used technologies in positive energy buildings, the device allows converting the available solar energy into heat and electricity at the same time. In this study, a comparative analysis is introduced between two different types of solar conversion devices: conventional hybrid solar air collector (PV/T-Air) and photovoltaic (PV) module. Also, a parametric study was performed to know the impact of different parameters related to the performance of both solar systems. A numerical system based on the fourth order Runge–Kutta iteration method, is used in this study, founded on a strong coupling between the heat balance equations and the different electrical and thermal parameters of both configurations that are included in this work. The energy performance evaluation was applied to the climatic conditions of El Jadida city, located in Morocco. The numerical results indicates that the estimated value of the daily average overall energy conversion efficiency attains: 30.22% for the PV module, and 52.14% for the examined hybrid air collector (PV/T-Air). These results are calculated with an air mass flow rate of 0.0215 kg/s, and these values are according to the meteorological data collected on the site of El Jadida city for a sunny day in July.

PECULIARITIES OF THE PV-MD PHOTOMODULE STRUCTURE FORMATION DURING THE ELECTRICAL ENERGY AND DISTILLATE PRODUCTION

The operating conditions of the photomodule are largely determined by the thermal regime, which affects the efficiency of electricity generation. The use of a forced cooling system in the photomodule with the implementation of the salt water distillation process allows you to control the thermal regime and obtain an additional product in the form of fresh water. The choice of the method of controlling the cooling process and the mode of its implementation makes it possible to achieve a rational combination of electrical and technological productivity of the photomodule. In this paper, analytical studies of the formation of the temperature field of the absorber of the hybrid solar collector (PV-MD) during cooling due to the evaporation of the heat carrier and recovery of the heat of the formed steam were carried out. The research method makes it possible to analyze the characteristics of the PV-MD collector, namely, the heating temperature of the absorber and coolant, as well as the performance of the distillate system, depending on the structure of the module and its operating conditions. The aim of the work is to develop a method for calculating the thermal performance characteristics of the hybrid solar collector in the conditions of a cascade method of heat and mass transfer of salt solution and distillate and to identify the rational architecture of the device. A complex mathematical model of local analysis of heat and mass exchange processes of a hybrid solar collector for real solar and climatic conditions is used. The analysis of heat and mass transfer in variant conditions showed that the degree of uniformity of the absorber temperature field, which depends on the efficiency of electricity production, when applying the PV-MD method is the same as for the PVT method. Cascade recovery of thermal energy using the PV-MD method for collectors of typical sizes is limited in efficiency to two stages. The generalized dependences for determining the technological productivity of the two-stage PV-MD collector in terms of distillate and absorber temperature when the external operating conditions of the collector change, which can be used to evaluate the efficiency of converting solar energy into a technological product, have been obtained.

Simulation of Hybrid Solar Collector Operation in Heat Supply System

The paper focuses on the investigation and the simulation of the efficiency of a hybrid solar collector in a heat supply system consisting of two separate units, namely a heat storage tank and a flat solar collector, which are interconnected by pipelines. The study includes the analysis and calculation of the thermal parameters of the system for one day and the determination of the optimal values of the flow rate of the heat carrier in the solar collector and the mass of the heat carrier in the heat storage tank to achieve maximum thermal efficiency of the system. The authors use SolidWorks software and additional scripts programmed using Python to simulate the operation of the solar collector and to calculate its thermal efficiency. The results of the study show the high potential of hybrid solar collectors for efficient generation and accumulation of thermal energy both for households and small industries. This paper may be useful for engineers and scientists working in the field of alternative energy sources and energy-efficient systems.