This document describes the performance evaluation of a hybrid modified micro-channel solar cell thermal tile through experimental validation. An indoor test setup and prototype tile were developed to study the tile's performance over different light intensities. The thermal and electrical efficiencies were found to be 35.7% and 12.4%, respectively. Overall energy and exergy analyses were also carried out based on the experimental results. Previous studies on hybrid photovoltaic thermal systems and their efficiency improvements are reviewed.
Financial Evaluation of Solar Powered Absorption Cooling System for Computer ...IRJET Journal
This document evaluates the financial feasibility of a solar powered absorption cooling system for a computer laboratory in Bharatpur, India. It finds that:
1. The system is technically feasible, achieving a solar fraction of 0.52-0.75 depending on the collector area. However,
2. Financially, the system is currently not feasible due to the high initial costs of absorption chillers and solar collectors. It provides only marginal annual savings, resulting in very high payback periods of 67-83 years.
3. A sensitivity analysis found that with reduced total investment costs (e.g. due to technology improvements) and increased electricity prices in the future, the payback period could decrease significantly
Indoor and outdoor investigation comparison of photovoltaic thermal air colle...journalBEEI
Photovoltaic technology is one of renewable energy technology very hopeful, especially photovoltaic thermal system or PVT system. A PVT system solar air collector produces hot air and electricity simultaneously. In this study, indoor and outdoor investigation comparison of PVT system solar air collector has tested at the National University of Malaysia. The indoor and outdoor investigation conducted with variation mass flow rates from 0.01 kg/s to 0.05 kg/s at the solar intensity of 820 W/m2. Indoor and outdoor evaluation is conducted to precisely evaluate the performance improvement theorized by the researcher. The comparison between the indoor and outdoor outcome purposed to confirm each testing and attraction decision. The outdoor investigation outcomes were agreement with indoor results. Indoor investigation outcomes reliably with outdoor investigation outcomes indicated by accuracy results.
EXPERIMENTAL INVESTIGATION OF THERMAL PERFORMANCE OF CURTAIN-WALL-INTEGRATED ...ijiert bestjournal
This document presents the results of an experimental investigation into the thermal performance of a curtain wall-integrated solar heater using different working fluids, including water and copper oxide nanofluid. Experiments were conducted with mass flow rates varying from 36 to 108 liters per hour. Higher efficiencies were found when using the 3% nanofluid compared to water alone. Outlet water temperature also increased at lower mass flow rates for both fluids. For a given fluid, efficiency slightly increased with higher mass flow rates. The study concluded the nanofluid improved the thermal performance and increased the outlet temperature of hot water compared to just using water.
Conventional fuels are not free, scarce and expensive, and its future cost and availability are uncertain. Hence, the usage of solar energy in applications will probably increase and further become economically feasible in the near future. Solar energy is free, clean, and renewable and has been widely used in electricity generation and thermal energy via photovoltaic thermal (PVT) system. PVT is a hybrid system consists of a PV panel and a solar collector in a single unit to simultaneously produce electricity and thermal energy. In this review, energy and exergy efficiency for water-based PVT systems is presented. As conclusion, the study on exergy is still limited and is recommended to be furthered in order to obtained useful energy generation by the system.
The document experimentally and numerically investigates the performance of photovoltaic solar modules (PVSMs) using continuous water cooling techniques (CCT) and intermittent water cooling techniques (ICT). Two identical mono-crystalline PVSMs were tested - one connected to a closed-loop water cooling system and one without cooling. Mathematical models were developed and MATLAB was used to simulate performance. Results showed the average cooling rate for ICT and CCT were 3.4804°C/min and 3.1617°C/min, higher than without cooling. Output power, fill factor, and electrical efficiency were also enhanced more with ICT compared to CCT. Energy enhancement for ICT was 6.308% while CCT resulted in
Enhancement of the output power generated from a hybrid solar thermal systemeSAT Journals
Abstract This paper investigates the output power and increased the efficiency of a hybrid Photovoltaic/ Thermal (PV/T) modules through utilizing the heat generated from the surface of panels by one axial tracking of the hybrid PV/Tsystem by means of zenith angle and decreasing the heat generated from the PV modules by controlling the flow rate of the system. A comparison between theoretical and experimental work results for fixed and tracking PV/T hybrid system is presented. Comsol software package used to simulate the electromagnetic waves produced by the sun through solving Maxwell's equations in three dimensions and the sun irradiance is assumed to be Gaussian distribution across the twelve mourning hours. Beside that an experimental work is presented depending on the results conjured from the theoretical experience used in Comsol Multiphysics In the second part of the experimental work, one axial sun-tracking system is designed where the movement of a photo-voltaic module is controlled to follow the Sun’s radiation using a Data acquisition card (DAQ) unit. Finally an active cooling system is designed and conducted to cool the fixed and tracking modules at which an absorber system consists of copper pipe welded with aluminium plate is attached underneath the PV modules to allow water flowing below the modules. In addition to the above an electrical analysis for both systems are presented where I-V, P-V, power with 12 mourning hour’s and electrical efficiency. Beside that the thermal analysis for the fixed and tracking PV modules and the piping water are presented where the input, output temperatures, the total energy of heat losses and thermal efficiency are calculated. As a result, a significant enhancement in the total electrical efficiency is observed with acceptable increase in the output water temperature. Keywords: Cooling systems; DAQ; Hybrid; Comsol Multiphysics; Mat lab; Solid work; Lab view.…
Design and Performance Analysis of Solar Powered Absorption Cooling System fo...IRJET Journal
- The document discusses the design and performance analysis of a solar powered absorption cooling system for a computer lab located in Bharatpur, India.
- The peak cooling load of the computer lab is calculated to be 34.94 kW, so a 10TR vapor absorption cooling system is adopted.
- Simulations are carried out using the TRANSOL program to analyze the performance of the solar cooling system using different solar collector types and areas. Parameters like solar fraction, primary energy savings, and electrical COP are evaluated.
- It is concluded that the solar thermal cooling system can achieve good solar fractions between 0.52-0.75 and primary energy savings up to 52% for the considered location and collector areas.
This document summarizes an article from the International Journal of Mechanical Engineering and Technology that analyzes the performance of an oscillatory flow heat exchanger design for a hybrid solar water system. The study compares the performance of a commercial PV module versus a hybrid PV/T system with an oscillatory flow heat exchanger attached. Key findings include the hybrid system achieving a combined PV/T efficiency of 53.7% at a solar irradiance of 918 W/m2 and water flow rate of 0.035 kg/sec, representing an improvement over the commercial PV module alone. The hybrid system also achieved a higher PV module efficiency of 11.7% under these conditions due to cooling from the heat exchanger.
Financial Evaluation of Solar Powered Absorption Cooling System for Computer ...IRJET Journal
This document evaluates the financial feasibility of a solar powered absorption cooling system for a computer laboratory in Bharatpur, India. It finds that:
1. The system is technically feasible, achieving a solar fraction of 0.52-0.75 depending on the collector area. However,
2. Financially, the system is currently not feasible due to the high initial costs of absorption chillers and solar collectors. It provides only marginal annual savings, resulting in very high payback periods of 67-83 years.
3. A sensitivity analysis found that with reduced total investment costs (e.g. due to technology improvements) and increased electricity prices in the future, the payback period could decrease significantly
Indoor and outdoor investigation comparison of photovoltaic thermal air colle...journalBEEI
Photovoltaic technology is one of renewable energy technology very hopeful, especially photovoltaic thermal system or PVT system. A PVT system solar air collector produces hot air and electricity simultaneously. In this study, indoor and outdoor investigation comparison of PVT system solar air collector has tested at the National University of Malaysia. The indoor and outdoor investigation conducted with variation mass flow rates from 0.01 kg/s to 0.05 kg/s at the solar intensity of 820 W/m2. Indoor and outdoor evaluation is conducted to precisely evaluate the performance improvement theorized by the researcher. The comparison between the indoor and outdoor outcome purposed to confirm each testing and attraction decision. The outdoor investigation outcomes were agreement with indoor results. Indoor investigation outcomes reliably with outdoor investigation outcomes indicated by accuracy results.
EXPERIMENTAL INVESTIGATION OF THERMAL PERFORMANCE OF CURTAIN-WALL-INTEGRATED ...ijiert bestjournal
This document presents the results of an experimental investigation into the thermal performance of a curtain wall-integrated solar heater using different working fluids, including water and copper oxide nanofluid. Experiments were conducted with mass flow rates varying from 36 to 108 liters per hour. Higher efficiencies were found when using the 3% nanofluid compared to water alone. Outlet water temperature also increased at lower mass flow rates for both fluids. For a given fluid, efficiency slightly increased with higher mass flow rates. The study concluded the nanofluid improved the thermal performance and increased the outlet temperature of hot water compared to just using water.
Conventional fuels are not free, scarce and expensive, and its future cost and availability are uncertain. Hence, the usage of solar energy in applications will probably increase and further become economically feasible in the near future. Solar energy is free, clean, and renewable and has been widely used in electricity generation and thermal energy via photovoltaic thermal (PVT) system. PVT is a hybrid system consists of a PV panel and a solar collector in a single unit to simultaneously produce electricity and thermal energy. In this review, energy and exergy efficiency for water-based PVT systems is presented. As conclusion, the study on exergy is still limited and is recommended to be furthered in order to obtained useful energy generation by the system.
The document experimentally and numerically investigates the performance of photovoltaic solar modules (PVSMs) using continuous water cooling techniques (CCT) and intermittent water cooling techniques (ICT). Two identical mono-crystalline PVSMs were tested - one connected to a closed-loop water cooling system and one without cooling. Mathematical models were developed and MATLAB was used to simulate performance. Results showed the average cooling rate for ICT and CCT were 3.4804°C/min and 3.1617°C/min, higher than without cooling. Output power, fill factor, and electrical efficiency were also enhanced more with ICT compared to CCT. Energy enhancement for ICT was 6.308% while CCT resulted in
Enhancement of the output power generated from a hybrid solar thermal systemeSAT Journals
Abstract This paper investigates the output power and increased the efficiency of a hybrid Photovoltaic/ Thermal (PV/T) modules through utilizing the heat generated from the surface of panels by one axial tracking of the hybrid PV/Tsystem by means of zenith angle and decreasing the heat generated from the PV modules by controlling the flow rate of the system. A comparison between theoretical and experimental work results for fixed and tracking PV/T hybrid system is presented. Comsol software package used to simulate the electromagnetic waves produced by the sun through solving Maxwell's equations in three dimensions and the sun irradiance is assumed to be Gaussian distribution across the twelve mourning hours. Beside that an experimental work is presented depending on the results conjured from the theoretical experience used in Comsol Multiphysics In the second part of the experimental work, one axial sun-tracking system is designed where the movement of a photo-voltaic module is controlled to follow the Sun’s radiation using a Data acquisition card (DAQ) unit. Finally an active cooling system is designed and conducted to cool the fixed and tracking modules at which an absorber system consists of copper pipe welded with aluminium plate is attached underneath the PV modules to allow water flowing below the modules. In addition to the above an electrical analysis for both systems are presented where I-V, P-V, power with 12 mourning hour’s and electrical efficiency. Beside that the thermal analysis for the fixed and tracking PV modules and the piping water are presented where the input, output temperatures, the total energy of heat losses and thermal efficiency are calculated. As a result, a significant enhancement in the total electrical efficiency is observed with acceptable increase in the output water temperature. Keywords: Cooling systems; DAQ; Hybrid; Comsol Multiphysics; Mat lab; Solid work; Lab view.…
Design and Performance Analysis of Solar Powered Absorption Cooling System fo...IRJET Journal
- The document discusses the design and performance analysis of a solar powered absorption cooling system for a computer lab located in Bharatpur, India.
- The peak cooling load of the computer lab is calculated to be 34.94 kW, so a 10TR vapor absorption cooling system is adopted.
- Simulations are carried out using the TRANSOL program to analyze the performance of the solar cooling system using different solar collector types and areas. Parameters like solar fraction, primary energy savings, and electrical COP are evaluated.
- It is concluded that the solar thermal cooling system can achieve good solar fractions between 0.52-0.75 and primary energy savings up to 52% for the considered location and collector areas.
This document summarizes an article from the International Journal of Mechanical Engineering and Technology that analyzes the performance of an oscillatory flow heat exchanger design for a hybrid solar water system. The study compares the performance of a commercial PV module versus a hybrid PV/T system with an oscillatory flow heat exchanger attached. Key findings include the hybrid system achieving a combined PV/T efficiency of 53.7% at a solar irradiance of 918 W/m2 and water flow rate of 0.035 kg/sec, representing an improvement over the commercial PV module alone. The hybrid system also achieved a higher PV module efficiency of 11.7% under these conditions due to cooling from the heat exchanger.
Overview on recent photovoltaic module cooling methods: advances PVT systems IJECEIAES
Renewable energy had been monopolized the research area in these past decade up till nowadays, due to its reliability and future in global production of electrical and thermal energy. Narrowing down the scope to the photovoltaic thermal (PVT) system, lots of improvements had been implied both theoretically and experimentally. One of the most attractive applications of PVT water or air-based collectors is building integrated photovoltaic thermal (BIPVT) system, which has undergone rapid developments in recent years. This review paper comprises the research findings on the improvements that had been integrated by PVT systems as well as well as personal and cited remarks on advancements on cooling techniques on PVT system.
Hybrid Photovoltaic and thermoelectric systems more effectively converts solar energy into electrical energy. Two sources of energy are used one of the energy is solar,that converts radiant light into electrical energy and heat energy which will convert heat into electricity.Photovoltaic cells and thermoelectric modules are used to capture and convert the energy into electricity.Furthermore solar-thermoelectric hybrid system is environmental friendly and has no harmful emissions.Solar-thermoelectric hybrid system increases the overall reliability without sacrificing the quality of power generated.In this paper an overview of the previous research and development of technological advancement in the solar-thermoelectric hybrid systems is presented.
Experimental study of a tubular solar still with phase change materialIAEME Publication
1. Experiments were carried out on a tubular solar still integrated with stearic acid as a phase change material in Allahabad, India.
2. The daily energy efficiency was 21.87% and daily exergy efficiency was 0.857%. Productivity increased with increasing water temperature according to the correlation P=5.489Tw - 169.9, with an R2 value of 0.804.
3. The use of a phase change material increased nighttime productivity and the overall productivity of the solar still.
This document summarizes a computational study on using finned heat pipes to cool photovoltaic (PV) solar panels. The study uses computational fluid dynamics (CFD) to model heat transfer from a solar panel through a heat pipe with attached fins. The CFD analysis shows that attaching fins to a heat pipe can reduce the temperature of a solar panel by up to 20°C compared to no cooling. This temperature reduction can increase the panel's efficiency and power output. The study aims to develop a passive cooling system for PV panels using a low-cost finned heat pipe design.
Use of exhaust heat energy of two wheelers to generate power by seebeck effectIRJET Journal
This document summarizes research on using thermoelectric generators to convert waste heat from vehicle exhaust into electricity. It discusses how the Seebeck effect allows direct conversion of temperature differences into electric voltage. Studies have placed thermoelectric modules in contact with exhaust systems to generate power from the temperature difference between hot exhaust gases and coolant. The document reviews several past studies on thermoelectric generator design, materials, and power generation performance in vehicle exhaust systems. It finds that while thermoelectric generators can recover some wasted heat, the potential power is usually just enough to power vehicle accessories rather than significantly improving fuel efficiency. Proper system design is needed to maximize energy recovery from exhaust, cooling, and lubrication waste heat streams.
This document provides a review of previous research on thermoelectric generators. It begins with an introduction to solar energy and thermoelectric generation technologies. It then discusses the basic components of a thermoelectric module, including the thermocouple. The document reviews three previous works: 1) fabrication and testing of flat plate solar thermoelectric generators for near-earth orbits, which achieved power outputs of 3-3.3 watts; 2) development of a high efficiency thermoelectric power generator using bismuth telluride that achieved a maximum efficiency of 1.85%; 3) parametric analysis and modeling of a solar heat pipe thermoelectric generator unit comprising a thermoelectric module, finned heat pipe,
Review of water-nanofluid based photovoltaic/thermal (PV/T) systemsIJECEIAES
The document summarizes research on water-nanofluid based photovoltaic/thermal (PV/T) systems. It discusses the basic concepts of PV/T systems and how nanofluids can improve performance by increasing thermal conductivity. Several studies are reviewed that show nanofluids can enhance the overall efficiency of PV/T systems compared to air or water alone as heat transfer fluids. Key factors like nanoparticle size and concentration, thermal conductivity, preparation methods, and optical properties are considered. The document concludes nanofluids aim to replace existing fluids due to limitations overcome by their improved thermal and optical characteristics.
IRJET- Dynamic Performance Characteristics of a Thermoelectric GeneratorIRJET Journal
This document describes an experimental study of the dynamic performance characteristics of a thermoelectric generator (TEG) under different operating conditions. The study investigates the influence of input heat rate and the use of fins on the TEG's transient and steady-state performance. Experimental results show that increasing the input heating rate leads to a higher temperature difference across the TEG and higher power output. Additionally, using fins to aid heat dissipation from the cold side improves performance by lowering its temperature and further increasing the temperature difference.
Energy and exergy efficiency of a flat plate solar collector using pH treated...Sabiha Akter Monny
This document examines the energy and exergy efficiency of a flat plate solar collector using pH treated Al2O3 nanofluid as the working fluid. Experiments were conducted using 0.1% and 0.3% volume fractions of Al2O3 nanoparticles approximately 13 nm in size, with mass flow rates varying from 0.5 to 1.5 kg/min. Results showed that nanofluids increased energy efficiency up to 83.5% and exergy efficiency up to 20.3% compared to using water alone. Thermal efficiency was found to be over 50%, higher than systems reported previously. The study provides new findings on stability and exergy analysis of a solar collector system operated with a pH controlled nanofluid.
Experiment study of water based photovoltaic-thermal (PV/T) collectorIJECEIAES
Solar radiation can be converted to the electrical energy and thermal energy by photovoltaic panel and solar collector. In this experiment, PV/T collector was designed, fabricated and tested its performance. The experiment conducted on PV/T collector with water flow at mass flow rate 0.012 kg/s to 0.0255 kg/s. The water flow with the stainless stell absorber help the PV/T collector in increasing the convection of thermal heat transfer. The power output increase with increase of radiation. The efficiency of PVT varies with different intensity of radiation which stated in this experiment for 750 W/m2 and 900 W/m2. The analysis of energy and exergy are excuted and results show energy output for water based PV/T collector are 346 W for solar radiation 700 W/m2 and 457 W for solar radiation 900 W/m2. Meanwhile the total exergy output compared to the PV panel without stainless stell absorber, which the exergy increased by 22.48% for 700 W/m2 and 20.87% for 900 W/m2.
Exergy Assessment of Photovoltaic Thermal with V-groove Collector Using Theor...TELKOMNIKA JOURNAL
The solution of the environmental problems because of fuel fossil is to use new and renewable
energy. There are many studies about energy analysis of solar collector with v-groove but exergy analysis
of photovoltaic thermal system with v-groove is still less especially by theoretical study. Photovoltaic
thermal with v-groove collector has been conducted the exergy analysis by theoretical assessment. The
matrix inversion methods were used to analyze the energy balance equation. The theoretical assessment
was conducted under the solar intensity of 385 W/m2, 575 W/m2, and 875 W/m2 and mass flow rate
between 0.01 and 0.05 kg/s. The maximum exergy efficiency and exergy of PVT system with v -groove
collector were 17.80% and 86.32 Watt at the solar intensity of 875 W/m2.
This document discusses the simulation and theoretical investigation of transparent glass photovoltaic-thermal (PV/T) water collectors. The existing PV/T systems have poor thermal performance, especially on non-sunny days. The authors designed a new PV/T system with transparent photovoltaic panels to overcome this limitation. They used MATLAB Simulink to simulate the system and expected it to have higher performance than existing PV/T systems. The document provides background on PV/T systems, reviews previous related work, describes the experimental setup and formulas used, and explains the theoretical simulation conducted in MATLAB.
The field of thermoelectrics has been growing steadily due to its ability to convert heat directly into electricity and to develop cost
effective, pollution free forms of energy conversion, aiming at efficiencies as high as possible. Low-dimensional structures have proved to be promising candidates for enhancing the thermoelectric properties of semiconductors. Here, we discuss the idea of implementation of dense arrays of armchair graphene nanoribbons in microfabricated structures to develop planar unileg thermoelectric microgenerators to convert heat fl ow into electrical energy. This paper is a discussion on energy scavenging to provide power autonomy to devices on a human body i.e., thermoelectric conversion of human heat and thereby summarizes the advantages of this material for commercial use because of its extra ordinary thermo electric performance.
Performance Improvement Analysis on PV/T Solar Water Collectors Connected in ...ijtsrd
The solar panel is one of the most sought after methods to produce electrical energy for domestic purposes. Solar PV/T systems converts solar irradiation into thermal and electrical energy. Module is made of Poly c-Si material. This experiment aims at analysing the comparative performance of hybrid solar PV/T water collectors connected in series and parallel. It was conducted in Saranathan College of Engineering, Tiruchirapalli-12. It is located at latitude of 10.7560-°N and longitude of 78.6513-°E. The maximum temperature of water obtained was 42.8-°C and 40.8-°C respectively in series and parallel. Overall the parallel connected PV/T systems performance is 12.12% higher than the series connected PV/T system. S. Paramaguru | P. Sivakumar | M. Sridharan | Dr. T. Senthilkumar"Performance Improvement Analysis on PV/T Solar Water Collectors Connected in Series and Parallel" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd14200.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/14200/performance-improvement-analysis-on-pvt-solar-water-collectors-connected-in-series-and-parallel/s-paramaguru
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Novel technique for maximizing the thermal efficiency of a hybrid pveSAT Journals
Abstract In this paper a comparison between numerical model and experimental work results for a fixed Photovoltaic/ Thermal (PV/T) hybrid system is presented. The simulation in this work is based on a numerical model in solving the equations and determining the Photovoltaic (PV) cells thermal characteristics using both MATLAB and COMSOL Multiphysics. COMSOL is simulating the electromagnetic waves produced by the Sun through solving Maxwell's equations in three dimensions using Finite Elements Methods (FEM) and the sun irradiance is assumed to be Gaussian distribution across the twelve mourning hours. Beside that an experimental work is presented depending on the results conjured from the theoretical experience used in Comsol Multiphysics. A Pulse Width Modulator (PWM) is used to control the solenoid valve operation. In addition to the above a thermal analysis for the fixed PV modules and the piping water is presented where the output water temperatures, rate of heat transfer, overall heat transfer coefficient and thermal efficiency are calculated. As a result, a significant enhancement in the total thermal efficiency is observed with acceptable increase in the output water temperature. Keywords: Cooling systems; DAQ; Hybrid; COMSOL MULTIPHYSICS; MATLAB; Solid work; Lab view.
This document describes a research focus on solar novel technologies developments. The researcher, S.A.H.Zamzamian, aims to study heat transfer using nanofluids and porous media in solar applications. Specifically, the research will examine heat transfer of silicone oil mixed with silica or silicon carbide nanostructures at high temperatures relevant to solar energy conversion. Previous projects conducted by the researcher include experimental studies examining heat transfer using nanofluids in flat-plate collectors, parabolic troughs, and vacuum tube collectors. The overall goal is to develop nanofluid technologies to enhance solar thermal absorption and efficiency.
comparative analysis of solar photovoltaic thermal (pvt) water and solarIJCMESJOURNAL
The present commercial photovoltaic solar cell (PV) converts solar energy into electricity with a relatively low efficiency less than 15%. More than 80% of the absorbed solar energy is dumped into the surroundings as heat after photovoltaic conversion. The electrical efficiency of photovoltaic system drops as its operating temperature rises and for this reason PV cooling is necessary. Therefore, stabilizing the temperature of photovoltaic modules at low level is highly desirable to improve the efficiency. Hybrid solar technology has the advantage of increasing the energy output per unit installed collector area. India as a tropical country is deemed to have a good potential of applying this technology. In this paper, solar PVT (Photovoltaic-Thermal) air and water collector hybrid systems were designed by using a poly crystalline silicon PV module as solar absorber and the comparative study was carried out. Air and water cooling of a commercial PV module configured as PVT air solar collector and PVT water solar collector by forced flow is studied. The energy and exergy performance of the PVT systems has been experimentally determined for various mass flow rates of fluids. The experimental result shows that the combined PVT system has got better performance than the simple PV and solar PVT water hybrid system has better efficiency than both. These systems are simple and suitable for building integration providing space heating depending on the season and for low temperature heating application.
1) The document describes an experiment to measure the thermal profile of an egg white cylinder cooking in boiling water using a thermocouple. Trials showed a linear relationship between temperature difference and time.
2) A COMSOL simulation modeled the system and also showed a linear relationship, though the slope differed from experimental results, likely due to modeling assumptions.
3) A theoretical model based on an infinite cylinder approximation had results close to experiments, with less than 1% error in slope, suggesting it adequately modeled the system.
Novel technique in charactarizing a pv module using pulse width modulatoreSAT Journals
This document summarizes a novel technique for characterizing photovoltaic (PV) modules using a pulse width modulator. The technique uses an electronic load circuit with power MOSFETs controlled by a pulse width modulation signal generated using LABVIEW. Experimental results from a 150W polycrystalline PV module showed high accuracy when compared to simulations performed using COMSOL Multiphysics and MATLAB. The technique provides accurate characterization with lower cost and simplicity compared to previous methods.
Solar photovoltaic thermal (PV/t) parabolic trough collector systemManav Shah
This system consists of concentrating parabolic trough collector to magnify the solar radiation onto the focal point where absorber tube has been placed. Working fluid such as water is passed from the tube with the help of pump. In order to increase the overall efficiency of the system, photovoltaic cells are placed on the absorber tube so that hot water and electricity can be produced from one integrated system.
Photovoltaic thermal hybrid solar system for residential applicationseSAT Journals
Abstract Electrical and thermal energy have wider applications in the life of mankind. Solar Photovoltaic Thermal (PVT) system is a hybrid system to produce both thermal and electrical energy. Chennai has an approximate climate and is highly suitable for using PVT hybrid systems. This paper presents the mathematical analyze of the thermal, electrical and exergetic performance of a PVT system augmented by a Flat Plate Collector (FPC) for a typical domestic application. The system is found to have 11 % of average electrical efficiency, 15 % of overall exergy efficiency and 56% overall energy efficiency. Keywords: energy, exergy, photovoltaic, hybrid, flat plate collector, solar water heater.
Overview on recent photovoltaic module cooling methods: advances PVT systems IJECEIAES
Renewable energy had been monopolized the research area in these past decade up till nowadays, due to its reliability and future in global production of electrical and thermal energy. Narrowing down the scope to the photovoltaic thermal (PVT) system, lots of improvements had been implied both theoretically and experimentally. One of the most attractive applications of PVT water or air-based collectors is building integrated photovoltaic thermal (BIPVT) system, which has undergone rapid developments in recent years. This review paper comprises the research findings on the improvements that had been integrated by PVT systems as well as well as personal and cited remarks on advancements on cooling techniques on PVT system.
Hybrid Photovoltaic and thermoelectric systems more effectively converts solar energy into electrical energy. Two sources of energy are used one of the energy is solar,that converts radiant light into electrical energy and heat energy which will convert heat into electricity.Photovoltaic cells and thermoelectric modules are used to capture and convert the energy into electricity.Furthermore solar-thermoelectric hybrid system is environmental friendly and has no harmful emissions.Solar-thermoelectric hybrid system increases the overall reliability without sacrificing the quality of power generated.In this paper an overview of the previous research and development of technological advancement in the solar-thermoelectric hybrid systems is presented.
Experimental study of a tubular solar still with phase change materialIAEME Publication
1. Experiments were carried out on a tubular solar still integrated with stearic acid as a phase change material in Allahabad, India.
2. The daily energy efficiency was 21.87% and daily exergy efficiency was 0.857%. Productivity increased with increasing water temperature according to the correlation P=5.489Tw - 169.9, with an R2 value of 0.804.
3. The use of a phase change material increased nighttime productivity and the overall productivity of the solar still.
This document summarizes a computational study on using finned heat pipes to cool photovoltaic (PV) solar panels. The study uses computational fluid dynamics (CFD) to model heat transfer from a solar panel through a heat pipe with attached fins. The CFD analysis shows that attaching fins to a heat pipe can reduce the temperature of a solar panel by up to 20°C compared to no cooling. This temperature reduction can increase the panel's efficiency and power output. The study aims to develop a passive cooling system for PV panels using a low-cost finned heat pipe design.
Use of exhaust heat energy of two wheelers to generate power by seebeck effectIRJET Journal
This document summarizes research on using thermoelectric generators to convert waste heat from vehicle exhaust into electricity. It discusses how the Seebeck effect allows direct conversion of temperature differences into electric voltage. Studies have placed thermoelectric modules in contact with exhaust systems to generate power from the temperature difference between hot exhaust gases and coolant. The document reviews several past studies on thermoelectric generator design, materials, and power generation performance in vehicle exhaust systems. It finds that while thermoelectric generators can recover some wasted heat, the potential power is usually just enough to power vehicle accessories rather than significantly improving fuel efficiency. Proper system design is needed to maximize energy recovery from exhaust, cooling, and lubrication waste heat streams.
This document provides a review of previous research on thermoelectric generators. It begins with an introduction to solar energy and thermoelectric generation technologies. It then discusses the basic components of a thermoelectric module, including the thermocouple. The document reviews three previous works: 1) fabrication and testing of flat plate solar thermoelectric generators for near-earth orbits, which achieved power outputs of 3-3.3 watts; 2) development of a high efficiency thermoelectric power generator using bismuth telluride that achieved a maximum efficiency of 1.85%; 3) parametric analysis and modeling of a solar heat pipe thermoelectric generator unit comprising a thermoelectric module, finned heat pipe,
Review of water-nanofluid based photovoltaic/thermal (PV/T) systemsIJECEIAES
The document summarizes research on water-nanofluid based photovoltaic/thermal (PV/T) systems. It discusses the basic concepts of PV/T systems and how nanofluids can improve performance by increasing thermal conductivity. Several studies are reviewed that show nanofluids can enhance the overall efficiency of PV/T systems compared to air or water alone as heat transfer fluids. Key factors like nanoparticle size and concentration, thermal conductivity, preparation methods, and optical properties are considered. The document concludes nanofluids aim to replace existing fluids due to limitations overcome by their improved thermal and optical characteristics.
IRJET- Dynamic Performance Characteristics of a Thermoelectric GeneratorIRJET Journal
This document describes an experimental study of the dynamic performance characteristics of a thermoelectric generator (TEG) under different operating conditions. The study investigates the influence of input heat rate and the use of fins on the TEG's transient and steady-state performance. Experimental results show that increasing the input heating rate leads to a higher temperature difference across the TEG and higher power output. Additionally, using fins to aid heat dissipation from the cold side improves performance by lowering its temperature and further increasing the temperature difference.
Energy and exergy efficiency of a flat plate solar collector using pH treated...Sabiha Akter Monny
This document examines the energy and exergy efficiency of a flat plate solar collector using pH treated Al2O3 nanofluid as the working fluid. Experiments were conducted using 0.1% and 0.3% volume fractions of Al2O3 nanoparticles approximately 13 nm in size, with mass flow rates varying from 0.5 to 1.5 kg/min. Results showed that nanofluids increased energy efficiency up to 83.5% and exergy efficiency up to 20.3% compared to using water alone. Thermal efficiency was found to be over 50%, higher than systems reported previously. The study provides new findings on stability and exergy analysis of a solar collector system operated with a pH controlled nanofluid.
Experiment study of water based photovoltaic-thermal (PV/T) collectorIJECEIAES
Solar radiation can be converted to the electrical energy and thermal energy by photovoltaic panel and solar collector. In this experiment, PV/T collector was designed, fabricated and tested its performance. The experiment conducted on PV/T collector with water flow at mass flow rate 0.012 kg/s to 0.0255 kg/s. The water flow with the stainless stell absorber help the PV/T collector in increasing the convection of thermal heat transfer. The power output increase with increase of radiation. The efficiency of PVT varies with different intensity of radiation which stated in this experiment for 750 W/m2 and 900 W/m2. The analysis of energy and exergy are excuted and results show energy output for water based PV/T collector are 346 W for solar radiation 700 W/m2 and 457 W for solar radiation 900 W/m2. Meanwhile the total exergy output compared to the PV panel without stainless stell absorber, which the exergy increased by 22.48% for 700 W/m2 and 20.87% for 900 W/m2.
Exergy Assessment of Photovoltaic Thermal with V-groove Collector Using Theor...TELKOMNIKA JOURNAL
The solution of the environmental problems because of fuel fossil is to use new and renewable
energy. There are many studies about energy analysis of solar collector with v-groove but exergy analysis
of photovoltaic thermal system with v-groove is still less especially by theoretical study. Photovoltaic
thermal with v-groove collector has been conducted the exergy analysis by theoretical assessment. The
matrix inversion methods were used to analyze the energy balance equation. The theoretical assessment
was conducted under the solar intensity of 385 W/m2, 575 W/m2, and 875 W/m2 and mass flow rate
between 0.01 and 0.05 kg/s. The maximum exergy efficiency and exergy of PVT system with v -groove
collector were 17.80% and 86.32 Watt at the solar intensity of 875 W/m2.
This document discusses the simulation and theoretical investigation of transparent glass photovoltaic-thermal (PV/T) water collectors. The existing PV/T systems have poor thermal performance, especially on non-sunny days. The authors designed a new PV/T system with transparent photovoltaic panels to overcome this limitation. They used MATLAB Simulink to simulate the system and expected it to have higher performance than existing PV/T systems. The document provides background on PV/T systems, reviews previous related work, describes the experimental setup and formulas used, and explains the theoretical simulation conducted in MATLAB.
The field of thermoelectrics has been growing steadily due to its ability to convert heat directly into electricity and to develop cost
effective, pollution free forms of energy conversion, aiming at efficiencies as high as possible. Low-dimensional structures have proved to be promising candidates for enhancing the thermoelectric properties of semiconductors. Here, we discuss the idea of implementation of dense arrays of armchair graphene nanoribbons in microfabricated structures to develop planar unileg thermoelectric microgenerators to convert heat fl ow into electrical energy. This paper is a discussion on energy scavenging to provide power autonomy to devices on a human body i.e., thermoelectric conversion of human heat and thereby summarizes the advantages of this material for commercial use because of its extra ordinary thermo electric performance.
Performance Improvement Analysis on PV/T Solar Water Collectors Connected in ...ijtsrd
The solar panel is one of the most sought after methods to produce electrical energy for domestic purposes. Solar PV/T systems converts solar irradiation into thermal and electrical energy. Module is made of Poly c-Si material. This experiment aims at analysing the comparative performance of hybrid solar PV/T water collectors connected in series and parallel. It was conducted in Saranathan College of Engineering, Tiruchirapalli-12. It is located at latitude of 10.7560-°N and longitude of 78.6513-°E. The maximum temperature of water obtained was 42.8-°C and 40.8-°C respectively in series and parallel. Overall the parallel connected PV/T systems performance is 12.12% higher than the series connected PV/T system. S. Paramaguru | P. Sivakumar | M. Sridharan | Dr. T. Senthilkumar"Performance Improvement Analysis on PV/T Solar Water Collectors Connected in Series and Parallel" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd14200.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/14200/performance-improvement-analysis-on-pvt-solar-water-collectors-connected-in-series-and-parallel/s-paramaguru
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Novel technique for maximizing the thermal efficiency of a hybrid pveSAT Journals
Abstract In this paper a comparison between numerical model and experimental work results for a fixed Photovoltaic/ Thermal (PV/T) hybrid system is presented. The simulation in this work is based on a numerical model in solving the equations and determining the Photovoltaic (PV) cells thermal characteristics using both MATLAB and COMSOL Multiphysics. COMSOL is simulating the electromagnetic waves produced by the Sun through solving Maxwell's equations in three dimensions using Finite Elements Methods (FEM) and the sun irradiance is assumed to be Gaussian distribution across the twelve mourning hours. Beside that an experimental work is presented depending on the results conjured from the theoretical experience used in Comsol Multiphysics. A Pulse Width Modulator (PWM) is used to control the solenoid valve operation. In addition to the above a thermal analysis for the fixed PV modules and the piping water is presented where the output water temperatures, rate of heat transfer, overall heat transfer coefficient and thermal efficiency are calculated. As a result, a significant enhancement in the total thermal efficiency is observed with acceptable increase in the output water temperature. Keywords: Cooling systems; DAQ; Hybrid; COMSOL MULTIPHYSICS; MATLAB; Solid work; Lab view.
This document describes a research focus on solar novel technologies developments. The researcher, S.A.H.Zamzamian, aims to study heat transfer using nanofluids and porous media in solar applications. Specifically, the research will examine heat transfer of silicone oil mixed with silica or silicon carbide nanostructures at high temperatures relevant to solar energy conversion. Previous projects conducted by the researcher include experimental studies examining heat transfer using nanofluids in flat-plate collectors, parabolic troughs, and vacuum tube collectors. The overall goal is to develop nanofluid technologies to enhance solar thermal absorption and efficiency.
comparative analysis of solar photovoltaic thermal (pvt) water and solarIJCMESJOURNAL
The present commercial photovoltaic solar cell (PV) converts solar energy into electricity with a relatively low efficiency less than 15%. More than 80% of the absorbed solar energy is dumped into the surroundings as heat after photovoltaic conversion. The electrical efficiency of photovoltaic system drops as its operating temperature rises and for this reason PV cooling is necessary. Therefore, stabilizing the temperature of photovoltaic modules at low level is highly desirable to improve the efficiency. Hybrid solar technology has the advantage of increasing the energy output per unit installed collector area. India as a tropical country is deemed to have a good potential of applying this technology. In this paper, solar PVT (Photovoltaic-Thermal) air and water collector hybrid systems were designed by using a poly crystalline silicon PV module as solar absorber and the comparative study was carried out. Air and water cooling of a commercial PV module configured as PVT air solar collector and PVT water solar collector by forced flow is studied. The energy and exergy performance of the PVT systems has been experimentally determined for various mass flow rates of fluids. The experimental result shows that the combined PVT system has got better performance than the simple PV and solar PVT water hybrid system has better efficiency than both. These systems are simple and suitable for building integration providing space heating depending on the season and for low temperature heating application.
1) The document describes an experiment to measure the thermal profile of an egg white cylinder cooking in boiling water using a thermocouple. Trials showed a linear relationship between temperature difference and time.
2) A COMSOL simulation modeled the system and also showed a linear relationship, though the slope differed from experimental results, likely due to modeling assumptions.
3) A theoretical model based on an infinite cylinder approximation had results close to experiments, with less than 1% error in slope, suggesting it adequately modeled the system.
Novel technique in charactarizing a pv module using pulse width modulatoreSAT Journals
This document summarizes a novel technique for characterizing photovoltaic (PV) modules using a pulse width modulator. The technique uses an electronic load circuit with power MOSFETs controlled by a pulse width modulation signal generated using LABVIEW. Experimental results from a 150W polycrystalline PV module showed high accuracy when compared to simulations performed using COMSOL Multiphysics and MATLAB. The technique provides accurate characterization with lower cost and simplicity compared to previous methods.
Solar photovoltaic thermal (PV/t) parabolic trough collector systemManav Shah
This system consists of concentrating parabolic trough collector to magnify the solar radiation onto the focal point where absorber tube has been placed. Working fluid such as water is passed from the tube with the help of pump. In order to increase the overall efficiency of the system, photovoltaic cells are placed on the absorber tube so that hot water and electricity can be produced from one integrated system.
Photovoltaic thermal hybrid solar system for residential applicationseSAT Journals
Abstract Electrical and thermal energy have wider applications in the life of mankind. Solar Photovoltaic Thermal (PVT) system is a hybrid system to produce both thermal and electrical energy. Chennai has an approximate climate and is highly suitable for using PVT hybrid systems. This paper presents the mathematical analyze of the thermal, electrical and exergetic performance of a PVT system augmented by a Flat Plate Collector (FPC) for a typical domestic application. The system is found to have 11 % of average electrical efficiency, 15 % of overall exergy efficiency and 56% overall energy efficiency. Keywords: energy, exergy, photovoltaic, hybrid, flat plate collector, solar water heater.
IEEE MULTIPHYSICS SIMULATION in COMSOLkhalil fathi
DO YOUR SIMULATION results really tell you if your design
is going to work? Accuracy sounds like an obvious thing to expect from the software you’re using. But it’s not something you can take for granted. That’s why multiphysics makes such a big difference: It is essential for capturing and coupling all the physical effects that interact in a realistic simulation.
Solar food drying Presentation for Thai delegationGordon Hirst
Sunlabob is a Laos-based social enterprise that provides renewable energy and clean water solutions. It launched in 2001 as the first commercial renewable energy company in Laos, with a mission to deliver clean energy and water to rural, off-grid communities in a sustainable, socially-minded way. Solar food drying is one solution offered, as it provides clean, hygienic drying using solar thermal or solar air systems while reducing costs, smoke, and greenhouse gas emissions compared to traditional drying methods. The document outlines the principles, design considerations, and examples of solar food drying systems.
The document provides an overview of Session 1 of a COMSOL training series, which introduces COMSOL software. It discusses multiphysics simulation, which involves modeling multiple interacting physical phenomena, like fluid flow, heat transfer, and electrodynamics. It gives examples of why simulation is useful, such as design validation, optimization, and analysis. It then outlines the basic steps of simulation: defining physical phenomena with PDEs, discretizing the domain, solving the PDEs, and visualizing results. Finally, it previews the example simulation of a microfluidic mixer.
AN APPLICATION OF SOLAR DRYER IN ORDER TO REMOVE MOISTURE AND DIFFERENCIATING...Anugrah Soy
Due to the current trends towards higher cost of fossil fuels and uncertainty regarding future cost
and availability, use of solar energy in food processing will probably increase and become more
economically feasible in the near future.The solar dryer is one of them which help to preserve our food and many eatable things like vegetable fruits and many more things . In this experiment we find that how much moisture removed from the sample which is present in solar dryer and the sample which is present in ordinary air and we compare both of them by mathematical calculation. In this paper we took green chili, some of the chili we put inside the dryer and some in the ordinary air and then compare their moisture removed with respect to time and temperature.
COMPUTER AIDED THERMAL DESIGN FOR A SOLAR DRYERAchal Gupta
This document summarizes previous work on solar dryer design and modeling. It discusses various types of solar dryers including direct, indirect, and forced circulation dryers. It reviews models for predicting solar radiation developed by ASHRAE and others. It also discusses thin layer versus deep bed drying and modeling the constant and falling rate periods of drying. Previous studies on designing, testing, and modeling solar dryers and collectors are summarized. The document establishes the need for a computer model to predict solar radiation and design solar dryers tailored to conditions at different locations.
Principles, Classification and Selection of Solar DryersiMentor Education
A comprehensive review of the fundamental principles governing the drying process with classification of the practically realized various designs and selection of solar
dryers for drying of agricultural and marine products has been presented. The classification clearly illustrates that the solar dryer designs can be grouped systematically according to their operating temperature ranges, heating
sources/modes and operational modes. It is difficult to have one single criteria for the selection of a solar dryer for a specific region or a product as solar insolation and other parameters change frequently with geographical location, however the general rules of thumb are mentioned to assist in making the final selection. The final selection is generally based on the available insolation rate, production
throughput, flexibility requirements, cost of fuel to run accessories as well as on the experience and judgment of the fabricator. As the solar dryer has a long life of about 20-40 years, the effect of a poor design can have a long-term impact on the economic health of the dryer.
Drying is the oldest preservation technique of agricultural products and it is an energy intensive process. High prices and shortages of fossil fuels have increased the emphasis on using alternative renewable energy resources. Drying of agricultural products using renewable energy such as solar energy is environmental friendly and has less environmental impact.
This document provides information on various drying methods for food, including thermal drying, tray drying, flash drying, drum drying, foam mat drying, freeze drying, vacuum drying, and fluidized bed drying. It describes the basic mechanisms and processes, advantages, disadvantages, and applications of each drying technique. Key points covered include how each method removes moisture from foods using heat, reduced pressure, or other means to preserve and process agricultural products.
This document describes solar food drying methods and provides details on a study comparing solar-assisted spouted bed drying to open-air drying of peas. Key points include:
1) Solar-assisted spouted bed drying uses hot air from a solar collector to dry peas inside a column, allowing for continuous particle-air contact and faster drying rates compared to open-air drying.
2) An experiment was conducted to evaluate the drying rates, quality parameters, shrinkage and rehydration of peas dried using the solar spouted bed dryer versus open-air drying.
3) Peas were dried in the solar spouted bed dryer and open-air using a mesh cage, and
This document provides an overview of drying as an important unit operation in the pharmaceutical industry. It discusses the purposes of drying, different periods of drying, and classifications of dryers. It also describes several types of dryers commonly used in the pharmaceutical industry, including tray dryers, rotary dryers, fluidized bed dryers, freeze dryers, and dryers for slurries and suspensions. Special dryers like microwave and radio frequency dryers are also briefly mentioned.
Solar photovoltaic/thermal air collector with mirrors for optimal tiltsIJECEIAES
This work is the result of a study of a photovoltaic/thermal air collector that concentrates solar radiation using two mobile mirrors to enhance electrical and thermal energy. The study is made for the site of Tetouan (Morocco) (longitude=-5°, latitude=35.25°) for a daily variation during typical days in May, June, September, and December, days considered as clear sky. To prove the effectiveness of the mirrors on the production of both electrical and thermal energy by the collector, we compared their electrical and thermal efficiency in two cases, without and with mirrors at the optimal positions. We validate the obtained simulation results by comparing them to the results from experimental studies published in the literature, for which a strong agreement was obtained. The model estimates the solar energy received by the hybrid collector during the day, to optimize the performance of the fixed collector, we have searched for the values of the optimal daily tilt angles of the two mirrors which allowed us to enhance the quantity of incoming solar radiation on the collector. The tilt angles depend on the sun’s elevation angle, the azimuth angle for typical days of the year.
Design of The Cooling System for Optimizing the Performance of Solar PanelIRJET Journal
This document describes the design and testing of three solar panel cooling systems. The cooling systems included two passive systems, one using an acrylic tank and the other using copper heat pipes and an aluminum heat sink. The third was an active water cooling system that pumped water over the solar panel surface. Experimental results showed that the water cooling system maintained the lowest solar panel temperatures, with panel temperatures around 60°C compared to 70°C without cooling. Cooling the panels in this way improved their electrical output and efficiency by reducing thermal losses at high temperatures.
Review of Various Cooling Techniques to Improve the Performance of the Solar ...IRJET Journal
This document reviews various cooling techniques that can improve the performance of solar photovoltaic panels. It discusses both active and passive cooling methods. Active methods discussed include forced air cooling using fans, forced water cooling using pumps to circulate water, and photovoltaic thermal systems. Passive methods discussed do not require moving parts and include using phase change materials, heat sinks, and natural convection. The document reviews several studies that have shown these cooling techniques can lower the operating temperature of solar panels and increase their electrical efficiency and power output.
This document describes the design and components of a solar powered air cooler. It consists of the following:
1. Solar panels that convert sunlight into electricity to power the system and charge batteries for use when sunlight is unavailable.
2. Batteries that store the solar-generated electricity.
3. A pump that circulates water through the system, powered by a motor that runs off the stored battery power.
4. Cooling pads made of materials that absorb heat from incoming hot air. The cooled air is then blown out by an electric fan, also powered by the stored battery power, to provide comfortable indoor cooling without relying on electricity from the grid.
The document outlines the components, design
COMPUTATIONAL STUDY OF COOLING OF PV SOLAR PANEL USING FINNED HEAT PIPE TECHN...IAEME Publication
Various solar energy technologies exist and they have different application techniques in the generation of electrical power. The widespread use of photovoltaic (PV) modules in such
technologies has been relatively high costs and low efficiencies. The efficiency of PV panel decreases as the operating temperature increases. This is due to reflection from the top surface, absorption of heat by the parts other than the cell, absorption of heat from the other portion of the spectrum.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Review of Enhancements in Absorber Plate Geometry for Solar Desalination: Key...IRJET Journal
This document reviews enhancements to absorber plate geometry for solar desalination. It explores how modifications like fins, baffles, corrugations, and steps can improve the productivity and efficiency of solar stills. Several studies that investigated different plate geometries are summarized, such as fins improving performance for the same water mass while corrugations perform better with consistent water depth. The document concludes with a table comparing the findings of these studies and a discussion of opportunities for future research.
EXPERIMENTAL STUDY OF A TUBULAR SOLAR STILL WITH PHASE CHANGE MATERIAL IAEME Publication
Experiments were carried out on tubular solar still in Allahabad climate conditions. Energy storage medium is used in still to produce distillate in the off sunshine hours .A correlation is
developed for the productivity of a still using experimental results .The proposed correlation has been validated with the experimental results .The regression coefficient approaches to unity and the correlation may be perfect positive with least error .
Experimental investigation on coupling evacuated heat pipe collector on singl...IAEME Publication
1) The document presents the results of an experimental investigation on coupling an evacuated heat pipe collector to a single basin single slope solar still to improve productivity.
2) The results show that coupling an evacuated heat pipe collector increased the solar still's productivity by 32% compared to the solar still alone, due to increased heat transfer and evaporation rate.
3) Testing also examined the effects of water depth, sun direction, and solar radiation on productivity. Productivity decreased with increased water depth and increased directly with solar radiation levels. The optimal sun direction was found to be 15 degrees west of geographic south for winter conditions.
To study the behavior of nanofluids in heat transfer applications a revieweSAT Journals
Abstract Using nanofluids as an innovative kind of liquid blend including trivial volume fraction (in percent) of millimeter or nanometer size powdered particles with base fluids is fairly a novel arena or idea. The objective of this presented review paper is to inspect the performance of the nanofluid-based solar collector (NBSC). In past few years for a number of experimental and industrial thermal engineering systems solar energy has proven to be the best input energy source. Nanofluids are the fluid that has shown various developments in the thermal properties over the past decade. In the field of nanotechnology, nano fluids have a great potential to enhance the rheological properties like thermal conductivity of base fluid like water, ethanol etc. Nanofluids are the suspension of mainly the base fluid like water in nanoparticles such as alumina (Al2O3) of size micro or milimetre and shows distinctive features than that of conservative fluids used. Because of better rheological properties nanofluids are utilized to build up the performance of conventional solar thermal engineering systems. The presented literature review presents a detailed discussion about the solar collectors, applications of nanofluids in solar collector and their augmentation in thermo physical properties. Keywords: Nano fluids, Nanoparticles, Solar collector, Thermal conductivity
Recent technological developments in pv+thermal technology a revieweSAT Journals
Abstract Large amount of work had been carried out and going on in research and technological development of solar energy systems. Many systems have been innovated and approved as a product industrial bodies as per its market potential. Theoretical models have been developed, manufactured within specified design constraints and tested to get desired results. Many have optimized the systems using different advanced tools, some have developed software techniques like neural network, and the product developed is studied for market potential. The journey is going on in order to increase efficiency of system and compete with conventional energy prizes. This article gives an overview about the trend of solar technology development, future key areas in which researchers have to work for sustainable and efficient solar technology. Keywords: - PV/T, solar energy, efficiency of PV cells, hybrid systems.
This document summarizes a study that used computational fluid dynamics (CFD) to investigate how varying the radius, height, and other dimensions of a solar chimney tower and chimney affect the efficiency and mass flow rate of a solar chimney power plant. The study created axisymmetric models of different plant designs in CFX software and solved conservation equations to simulate air flow and heat transfer. Results showed that chimney height and tower outlet radius are important parameters for improving power output. Optimal dimensions were identified. Contour plots showed changes in pressure, temperature, and velocity with different designs. The study concludes dimension choices involve economic tradeoffs between higher output power and construction costs.
CFD AND DOE STUDY THE EFFECT OF SOLAR CHIMNEY TOWER RADIUS, HEIGHT, CHIMNEY R...IAEME Publication
Solar chimney technology is a very promising solar thermal electricity generating technology. In this project CFD technology is used to investigate the changes in flow kinetic energy caused by the variation of tower flow area with height. It was found that the tower area change affects the efficiency and mass flow rate through the plant.
1. The document discusses applications of nanofluids in solar energy systems, specifically their use in improving the efficiency of solar collectors.
2. Adding small amounts of nanoparticles to the working fluid of solar collectors can significantly increase their efficiency until an optimal volume fraction of around 0.5% is reached.
3. Different types of nanofluids - including those with carbon nanotubes, silver, aluminum, and titanium dioxide nanoparticles - have been found to enhance collector efficiency compared to base fluids alone.
Proper ventilation in one of the primary requirements of any domestic or commercial buildings. The conventional method employs usage of air conditioning or air cooling systems which requires high power consumption. The solar driven ventilation systems can be used in buildings which doesn’t require any external power. The current research reviews various researches conducted in improving system of passive ventilation along use of phase change material as energy storage system. Passive design of buildings does not use the electrical and mechanical systems in providing comfortable indoor environment. Prem Shankar Sahu | Praveen Kumar | Ajay Singh Paikra "Review on Solar Chimney Ventilation" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd42427.pdf Paper URL: https://www.ijtsrd.comengineering/mechanical-engineering/42427/review-on-solar-chimney-ventilation/prem-shankar-sahu
Experimental Investigation Of Active Cooling Of Photovoltaic Cellsguest741138
The document presents the results of an experimental investigation into actively cooling photovoltaic cells. A hybrid photovoltaic/thermal system was designed and tested. Experiments were conducted with and without active air cooling of the PV panel. The results showed that active cooling significantly reduced the panel temperature and increased solar cell efficiency from 8-9% without cooling to 12-14% with cooling. Higher air flow rates through the cooling ducts further increased efficiency up to a point, after which additional increases in flow rate did not provide further gains.
Performance of water and diluted ethylene glycol as coolants for electronic c...IJERA Editor
As the number of transistors increases with new generation of microprocessor chips, the power draw and heat load to dissipate during operation increases. As a result of increasing the heat loads and heat fluxes the Conventional cooling technologies such as fan, heat sinks are unable to absorb and heat transfer excess heat dissipated by these new microprocessor. So, new technologies are needed to improve the heat removal capacity. In the present work single phase liquid cooling system with mini channel is analyzed and experimentally investigated. Mini channels are chosen as to provide higher heat transfer co-efficient than conventional channel. Copper pipes of 0.36 mm diameter are taken to fabricate heat sink and heat exchanger. A pump is used to circulate the fluid through heat sink and heat exchanger. A solid heated aluminium block to simulate heat generated electronic component is used and electrical input is supplied to the heated aluminium block and cooling system is placed over the heated block. The performance of the cooling system is analyzed from the experimental data obtained. It is experimentally observed that the mini channel liquid cooling system with water as a coolant has better performance than diluted ethylene glycol as coolant at different flow rates. The surface temperature of the heated aluminium block with convective heat transfer co-efficient is observed
Performance Improvement of Solar PV Cells using Various Cooling Methods: A Re...rahulmonikasharma
This document reviews various cooling methods that can be used to improve the performance of solar photovoltaic (PV) cells. It discusses both active cooling methods that require external power sources, such as fans, pumps or sprays, as well as passive cooling methods that do not require external power, such as using heat pipes, floating the PV panels, or attaching phase change materials. The document finds that cooling methods can lower the operating temperature of PV panels by 5-30 degrees Celsius, leading to efficiency improvements of up to 22% for active methods and up to 15% for passive methods. Maintaining lower temperatures through cooling also helps extend the lifetime of PV panels.
Building RAG with self-deployed Milvus vector database and Snowpark Container...Zilliz
This talk will give hands-on advice on building RAG applications with an open-source Milvus database deployed as a docker container. We will also introduce the integration of Milvus with Snowpark Container Services.
Dr. Sean Tan, Head of Data Science, Changi Airport Group
Discover how Changi Airport Group (CAG) leverages graph technologies and generative AI to revolutionize their search capabilities. This session delves into the unique search needs of CAG’s diverse passengers and customers, showcasing how graph data structures enhance the accuracy and relevance of AI-generated search results, mitigating the risk of “hallucinations” and improving the overall customer journey.
Encryption in Microsoft 365 - ExpertsLive Netherlands 2024Albert Hoitingh
In this session I delve into the encryption technology used in Microsoft 365 and Microsoft Purview. Including the concepts of Customer Key and Double Key Encryption.
“An Outlook of the Ongoing and Future Relationship between Blockchain Technologies and Process-aware Information Systems.” Invited talk at the joint workshop on Blockchain for Information Systems (BC4IS) and Blockchain for Trusted Data Sharing (B4TDS), co-located with with the 36th International Conference on Advanced Information Systems Engineering (CAiSE), 3 June 2024, Limassol, Cyprus.
Full-RAG: A modern architecture for hyper-personalizationZilliz
Mike Del Balso, CEO & Co-Founder at Tecton, presents "Full RAG," a novel approach to AI recommendation systems, aiming to push beyond the limitations of traditional models through a deep integration of contextual insights and real-time data, leveraging the Retrieval-Augmented Generation architecture. This talk will outline Full RAG's potential to significantly enhance personalization, address engineering challenges such as data management and model training, and introduce data enrichment with reranking as a key solution. Attendees will gain crucial insights into the importance of hyperpersonalization in AI, the capabilities of Full RAG for advanced personalization, and strategies for managing complex data integrations for deploying cutting-edge AI solutions.
Introducing Milvus Lite: Easy-to-Install, Easy-to-Use vector database for you...Zilliz
Join us to introduce Milvus Lite, a vector database that can run on notebooks and laptops, share the same API with Milvus, and integrate with every popular GenAI framework. This webinar is perfect for developers seeking easy-to-use, well-integrated vector databases for their GenAI apps.
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
Climate Impact of Software Testing at Nordic Testing DaysKari Kakkonen
My slides at Nordic Testing Days 6.6.2024
Climate impact / sustainability of software testing discussed on the talk. ICT and testing must carry their part of global responsibility to help with the climat warming. We can minimize the carbon footprint but we can also have a carbon handprint, a positive impact on the climate. Quality characteristics can be added with sustainability, and then measured continuously. Test environments can be used less, and in smaller scale and on demand. Test techniques can be used in optimizing or minimizing number of tests. Test automation can be used to speed up testing.
Sudheer Mechineni, Head of Application Frameworks, Standard Chartered Bank
Discover how Standard Chartered Bank harnessed the power of Neo4j to transform complex data access challenges into a dynamic, scalable graph database solution. This keynote will cover their journey from initial adoption to deploying a fully automated, enterprise-grade causal cluster, highlighting key strategies for modelling organisational changes and ensuring robust disaster recovery. Learn how these innovations have not only enhanced Standard Chartered Bank’s data infrastructure but also positioned them as pioneers in the banking sector’s adoption of graph technology.
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
2. 245 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
heating collector with single and double glass configurations and they concluded that that the system efficiency increases with
increase in collector length, mass flow rate and cell density, and decreases with increase in duct depth for both configurations.
An extensive investigation of the thermal, electrical, hydraulic and overall performances of flat plate photovoltaic thermal
(PVT) air collectors has been made by Hagazy (2000) and it has been observed that the flow channel (depth of channel/length
of channel) ratio is an important design parameter which influence the performance of PVT air collectors. Kalogirou (2001)
has carried out monthly performance of an unglazed hybrid PVT system under forced mode of operation for climatic condition
of Cyprus and it has been found that the hybrid system increases the mean annual efficiency of the PV solar system from 2.8%
to 7.7% and in addition covers 49% of the hot water needs of a house, thus increasing the mean annual efficiency of the
system to 31.7%.
Thermal modeling of building integrated photovoltaic system has been presented by Lee et al.(2001) and they have given
interesting modeling results on air cooled PV modules. Tiwari et al. (2006) have validated the theoretical and experimental
results for photovoltaic (PV) module integrated with air duct for composite climate of India and they concluded that an overall
thermal efficiency of PVT system is significantly increased due to utilization of thermal energy from PV module. Annual
performance of building integrated photovoltaic water –heating system for Hongkong climate has been presented by chow et
al.(2003) and they have observed that annual thermal and cell conversion efficiencies are 37.5% and 9.39%, respectively. An
experimental study on energy generation with a photovoltaic (PV) solar thermal hybrid system has been done Erdil et al.
(2008) and they concluded that the loss in the electrical energy generation is well offset by a large gain, Qw, in thermal energy
that is collected by the circulating water. Chow (2010) has reviewed the trend of development of the hybrid photovoltaic
thermal solar technology, in particular the advancements in recent years and the future work required.
Energy and exergy analysis of photovoltaic–thermal collector with and without glass cover has been discussed by Chow et
al. (2009) and they concluded that from the first law point of view, a glazed PVT system is found always suitable if we are to
maximize the quantity of either the thermal or the overall energy output. From the exergy analysis point of view however, the
increase of PV cell efficiency, packing factor, water mass to collector area ratio, and wind velocity are found favorable to go
for an unglazed system, whereas the increase of on-site solar radiation and ambient temperature are favorable for a glazed
system. Nayak and Tiwari (2008) have made exergy analysis of integrated photovoltaic thermal (IPVT) water heater under
constant flow rate and they observed that an overall exergy and thermal efficiency of IPVT is maximum at the hot water
withdrawal flow rate of 0.006 kg/s. Exergy analysis of integrated photovoltaic thermal solar (IPVTS) water heater under
constant flow rate and constant collection temperature modes has been done by Tiwari et al. (2009) and they observed that the
daily overall thermal efficiency of IPVTS system increases with increase constant flow rate and decrease with increase of
constant collection temperature. Performance analysis of a hybrid photovoltaic-thermal integrated system has also been done
by Radziemska (2009) who presented the concept of exergy analysis for evaluation of the PVT systems which is very useful
tools for the improvement and cost-effectiveness of the system. The performance in terms of overall annual thermal , exergy
gain and exergy efficiency of proposed micro-channel photovoltaic thermal module have been evaluated by Agrawal and
Tiwari (2011) and they concluded that proposed hybrid micro-channel photovoltaic thermal module gives better results than
single channel photovoltaic thermal module of Dubey et al. (2006) .
The main objective of this paper is to study on single modified solar cell thermal tile having micro-channel to see the effect
of intensity on overall performance of modified micro-channel solar cell thermal tile because till now large area of channel or
duct based photovoltaic thermal system has been found in literature. An attempt has been done to design modified micro-
channel solar cell thermal tile with experimental setup and its performance over different intensity in indoor conditions have
been examined.
2. Experimental setup
2.1 Modified Micro-channel solar cell thermal tile:
The present study has been carried out on single modified micro-channel solar cell thermal (MCSCT) tile. The MCSCT tile
consists of a single solar cell (mono crystalline silicon), rated at 2.2 Wp having dimensions 0.12 m length and 0.12 m width
has been considered and it has been mounted on a rectangular wooden channel. The channel has dimensions 0.12 m length,
0.12 m width and 5000 µm depth. The wooden channel has been sealed with putty and adhesive tape to avoid air leakage.
There is provision of inlet and outlet air to flow through the micro-channel. Air flow pattern of modified micro-channel solar
cell thermal tile has been shown in Figure. 1(a). The MCSCT tile has been placed on a mild steel platform of solar simulator
with a mechanism for up and down movement for varying the light intensity. A DC fan of 6.0 V and 0.1A has been used to
circulation of the air through the channel.
3. 246 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
Figure. 1(a). Air flow pattern over elementary area bdx of modified micro-channel solar cell thermal (MCSCT).
2.2 Solar simulator
A solar simulator (Figure. 1(b) )with a 3-phase lamp array is employed to imitate the necessary solar irradiation in the testing
of micro-channel solar cell thermal tile. The solar simulator has 28 tungsten halogen lamps (Philips manufactured; Model:
392472) each having 500W, 9000 lumens and rated at 240V and 11A. The halogen lamps are arranged in 7 × 4 matrices for
uniform distribution of irradiance on the MCSCT tile.
Figure.1(b) Photograph of solar simulator with micro-channel solar cell thermal (MCSCT) tile
The available area for testing is 1×2 m .The height of the simulator from the floor is 200 cm. The distance between platform
and halogen lamp is 100 cm. Intensity of simulator can be varied between 300 W/m2 to 1000 W/m2 by decreasing the gap of
solar simulator (halogen lamp) and platform.
2.3 Instrumentation
(i)Thermocouples: Calibrated copper-constantan thermocouples and digital temperature indicator are used to measure the
temperature at several locations, namely, back surface, inlet and outlet points of each collector and final outlet point. Digital
temperature indicator has a least count of 0.1oC.
(ii) Solarimeter: The intensity of solar radiation is measured by solarimeter having a least count of 20W/m2, manufactured
by CEL, India Ltd, Sahibabad (UP), India. Solarimeter has been calibrated with standard pyranometer.
(iii) Anemometer (Lutron-AM4201): It is conventional instrument used to measure the velocity of flowing air. The least
count of instrument is 0.1 m/s.
(iv) Infrared thermometer: The infrared thermometer is used to measure top surface temperature of modified micro-channel
solar cell thermal tile. Least count of the instrument is 0.1oC.
(v) Clamp meter: It is used for measurement of current and voltage. Least count of the instrument is 0.1A and 0.1V
respectively.
3. Thermal modeling of modified micro-channel solar cell thermal tile
To write the energy balance equation of modified micro-channel solar cell thermal (MCSCT) tile, the following assumptions
have been made:
*One dimensional heat-conduction is good approximation for present study.
*There is no temperature gradient along the thickness of MCSCT tile.
4. 247 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
*The specific heat of air remains constant. It does not change with rise in temperature of air.
*The system is in quasi-steady state.
*The ohmic losses in the MCSCT tile are negligible.
*There is stream line flow of air through the micro-channel at small flow rate.
.
Following Agrawal and Tiwari (2011) & Tiwari and Sodha (2006), the energy balance equation for modified
MCSCT tile can be written as
⎡α cτ g I ( t ) bdx ⎤ = ⎡U tca (Tc − Ta ) bdx + U tcf (T c −Tf ) bdx ⎤ + τ gηc I (t )bdx
⎣ ⎦ ⎣ ⎦ (1)
⎡ Rate of solar ⎤ ⎡ Rate of heat loss from ⎤ ⎡ Rate of heat transfer ⎤ ⎡ Rate of ⎤
⎢ energy available ⎥ = ⎢ top surface of solar cell ⎥ + ⎢ from solar cell to ⎥ + ⎢electrical energy ⎥
⎢ ⎥ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥
⎢ on solar cell
⎣ ⎥ ⎢ to ambient
⎦ ⎣ ⎥ ⎢ flowing fluid i.e. air ⎥ ⎢ produced
⎦ ⎣ ⎦ ⎣ ⎥
⎦
From Equation (1), the expression for cell temperature is
τ gα c I ( t ) − τ gηc I ( t ) + U tcaTa + U tcf Tf
Tc =
U tca + U tcf
or
α eff I ( t ) + U tcaTa + U tcf T f
Tc = (2)
U tca + U tcf
where α eff = τ g (α c − η c )
An expression for temperature dependent electrical efficiency of a MCSCT tile as given by Schott (1985) and Evans (1981)
is,
(
η = η0 ⎡1 − 0.0045 Tc − Ta ⎤
⎣ )⎦ (3)
Energy balance for air flowing in the micro-channel of solar cell thermal tile for elemental area bdx is given by
. dTf
Utcf (T −Tf )bdx =mf Cf
c dx+Ub(Tf −T )bdx
a (4)
dx
⎡ Rate of heat transfer ⎤ ⎡ The mass flow ⎤ ⎡ Rate of heat transfer ⎤
⎢ ⎥ ⎢ ⎥ ⎢ ⎥
⎢ from solar cell to ⎥ = ⎢ rate of flowing ⎥ + ⎢ from flowing fluid to ⎥
⎢flowing fluid i.e. air ⎥ ⎢ fluid i.e. air
⎣ ⎦ ⎣ ⎥ ⎢ ambient
⎦ ⎣ ⎥
⎦
Solving Equation (2) and Equation (4) with boundary condition at x=0, Tf = Tfi; one gets
⎡ ⎛ −bU x ⎞⎤ ⎛ −bU x ⎞
⎡hpαeff ⎤⎢
Tf = ⎢ I ( t ) +Ta ⎥ 1− exp⎜ . L ⎟⎥ +Tfi exp⎜ . L ⎟ (5)
⎣ UL ⎦⎢ ⎜ ⎟⎥
⎝ mf Cf ⎠⎦
⎜ ⎟
⎝ mf Cf ⎠
⎣
At, x=L, Tf =Tfo , the outlet air temperature of modified micro-channel solar cell thermal tile, is
⎡ ⎛ −bU L⎞⎤ ⎛ ⎞
⎡hpαeff ⎤⎢ ⎜ . L ⎟⎥ +Tfi exp⎜ −.bULL⎟
Tfo = ⎢ I ( t) +Ta ⎥ 1−exp (6)
⎣ UL ⎦⎢ ⎜ mf C ⎟⎥
⎝ f ⎠⎦
⎜ mf C ⎟
⎝ f ⎠
⎣
The average air temperature over the length of air channel below micro-channel solar cell thermal tile as obtained with help of
Equation. (5) is
−
1 L
Tf = ∫ Tf dx
L 0
5. 248 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
⎡ ⎛ ⎞⎤ ⎡ ⎛ ⎞⎤
⎢ 1 − exp ⎜ −.bU L L ⎟ ⎥ ⎢ 1 − exp ⎜ −.bU L L ⎟ ⎥
⎤⎢ ⎜ mf C ⎟⎥ ⎢ ⎜ m f C ⎟⎥
= (7)
⎡ h pα eff ⎝ f ⎠ ⎝ f ⎠
⎢ U I ( t ) + Ta ⎥ ⎢1 − ⎥ + T fi ⎢ ⎥
⎣ L ⎦ ⎢ bU L L ⎥ ⎢ bU L L ⎥
⎢ .
⎥ ⎢ .
⎥
⎢ mf Cf ⎥ ⎢ mf Cf ⎥
⎣ ⎦ ⎣ ⎦
For a number of modified MCSCT tiles connected in series, the outlet temperature of first MCSCT tile will be the inlet for
second MCSCT tile, the outlet temperature of second MCSCT tile will be the inlet for the third and so on. Hence, for a system
of N number of MCSCT tiles connected in series, the outlet air temperature from Nth MCSCT tile can be expressed in terms of
first MCSCT tile.
The outlet air temperature of N number of modified micro-channel solar cell thermal tiles connected in series is derived as
⎡ ⎛ −NbU L ⎞⎤ ⎛ ⎞
⎡hpαeff ⎤⎢ ⎜ . L ⎟⎥ +Tfi exp⎜ −NbUL L ⎟
TfoN = ⎢ I ( t ) +Ta ⎥ 1− exp (8)
⎦⎢ ⎜ mf C ⎟⎥ ⎜ mf C ⎟
.
⎣ UL ⎝ ⎠⎦ ⎝ ⎠
⎣ f f
The rate of useful thermal energy obtained for npv row of MCSCT tile connected in series is derived as
QU ,N = npv × mf Cf (TfoN − Tfi )
. .
(9)
or
⎡ ⎛ −NbU L ⎞⎤ ⎡ h α
. . ⎤
QU ,N = npv × mf Cf ⎢1− exp⎜ . L ⎟⎥ ⎢ p eff I ( t ) + Ta −Tfi ⎥ (10)
⎢ ⎜ mf C ⎟⎥ ⎣ UL ⎦
⎣ ⎝ f ⎠⎦
3.1 Instantaneous thermal efficiency
An instantaneous thermal efficiency of hybrid micro-channel solar cell thermal tile can be obtained as, Duffie and Beckman
(24) and Tiwari (25),
.
Q U ,N
η th = (11)
N Ac I (t )
m f Cf ⎡ ⎛ − NbU L ⎞⎤ ⎡ (T − T ) ⎤
.
ηth = ⎢1 − exp ⎜ . L ⎟⎥ ⎢hpαeff − U L fi a ⎥ (12)
U L NAc ⎢ ⎜ m f C ⎟⎥ ⎢ I (t ) ⎥
⎣ ⎝ f ⎠⎦ ⎣ ⎦
3.2 Electrical efficiency
Experimental efficiency of MCSCT tile can be calculated as
FF × Voc × I sc − I L × VL
ηe = (13)
Am × I (t )
where fill factor (FF) is measure of sharpness of the I-V curve. It indicates how well a junction was made in the cell and how
low is the series resistance. It can be lowered by the presence of series resistance and tends to be higher whenever the open
circuit voltage is high.
3.3 Energy Analysis
The energy analysis is based on the first law of thermodynamics, and the expression for overall thermal gain can be defined as,
∑Q
& = ∑ Qu ,thermal +
& ∑Q
&
u , electrical
(14)
u , total
η cpower
&
Q
where &
Qu ,thermal = uN (15)
1000
Overall thermal gain from a PVT system = Thermal energy collected by the PVT system + (Electrical output /ηcpower ).
6. 249 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
where, ηcpower is the electric power generation efficiency conversion factor of a conventional power plant for India.
This is so because electrical energy is a high-grade form of energy which is required for operation of DC motor. This electrical
energy has been converted to equivalent thermal by using electric power generation efficiency conversion factor as 0.20-0.40
for a conventional power plant, Huang et al. (26) and it depends on quality of coal. Usual value of this factor is taken as 0.38
for conversion.
3.4 Exergy Analysis
. The exergy analysis is based on the second law of thermodynamics, which includes accounting the total exergy inflow,
exergy outflow and exergy destructed from the system.
. ⎡ T + 273 ⎤
&
Exthermal = QU , N ⎢1 − a ⎥
⎢ T fo + 273 ⎥
⎣ ⎦
& ⎡η × A × I (t ) ⎤ & & &
Exelectrical = ⎢ ⎥ Exoverall = Exthermal + Exelectrical (16)
⎣ 1000 ⎦
where, A is area of module and Ts is the sun temperature in Kelvin.
3.5 Statistical analysis
To compare the theoretical and experimental results, the correlation coefficient (r) and root mean square percent
deviation (e) have been evaluated by using the following expression:
N ( ∑Xi ×Yi ) - ( ∑Xi )( ∑Yi )
r= (17)
N∑Xi2 - ( ∑Xi ) N∑Yi2 - ( ∑Yi )
2 2
and e =
∑ (ei )2 (18)
N
⎡ X i − Yi ⎤
where ei = ⎢ ⎥ × 100
⎣ Xi ⎦
4. Results and Discussions
In a series of experiments conducted, data have been recorded for different intensities for comparative evaluation on single
modified micro-channel solar cell thermal (MCSCT) tile. Theoretical value of cell temperature of modified MCSCT tile has
been computed from equation.(2) using MATLAB 7.0 at solar radiation (700 W/m2 ), constant mass flow rate(0.000145 kg/s)
and Tfi =38 0C. The variation of cell temperature with respect to time of single modified MCSCT tile for theoretical and
experimental results has been shown in Figure. 2 Figure shows that there is good agreement between theoretical and
experimental values. The correlation coefficient and root mean square percentage deviation between theoretical and
experimental results are 0.998 and 3.21, respectively. Similarly, equation. (8) has been used for calculating outlet temperature
of modified MCSCT tile using MATLAB 7.0 at solar radiation 700 W/m2 and Tfi =38 0C. The theoretical and experimental
results are validated for outlet air temperatures of single modfied MCSCT tile as shown in Figure. 3. The correlation
coefficient and root mean square percentage deviation between theoretical and experimental results are 0.995 and 4.37,
respectively.
Figure 2. Variation of cell temperature of single MCSCT tile at solar radiation 700 W/m2
7. 250 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
Figure 3. Variation of outlet air temperature of single modified MCSCT tile at solar radiation 700 W/m2
equation. (3) has been used for calculating the electrical efficiency of MCSCT tile. Figure. 4 shows the time variation of cell
temperature and electrical efficiency at different intensities 600 W/m2, 700 W/m2 and 800 W/m2 respectively. It has been
found that as intensity increases, electrical efficiency decreases because of rise in cell temperature and this result is in
accordance with result reported by earlier researchers, Zondag et al.(2002).
Figure 4. Variation of cell temperature and electrical efficiency of single MCSCT tile at different intensity.
It has also been observed that electrical efficiency for this MCSCT tile in the range of 13.5 % to 11.3 % at 800 W/m2
.Equation. (9) has been used for calculating rate of thermal gain for MCSCT tile and using this data in equation. (11), thermal
efficiency has been calculated .Fig. 5 shows the time variation of outlet temperature and thermal efficiency at different
intensities 600 W/m2, 700 W/m2 and 800 W/m2 respectively. It has been found that as intensity increases, outlet temperature of
MCSCT tile also increases and due to increase in outlet temperature , thermal efficiency is increased because inlet
temperature Tfi =38 0C is maintained constant. It has also been observed that as there is increase in duration of time, outlet air
temperature also increased and approaches the steady state condition after approximately two hours because of thermal
capacity of MCSCT tile. The maximum outlet air temperature 86.6 0C and thermal efficiency 35.7 % were observed at 800
W/m2 at steady state for single MCSCT tile.
Figure 5. Variation of outlet air and thermal efficiency of single MCSCT tile at different intensity
Figure. 6 shows the time variation of electrical power at different intensities. It has been observed that electrical power
decreases as time increases because temperature of MCSCT tile goes on increase as time increase on the basis of this one can
conclude that if fan were not installed there were more decrement in electrical power .One interesting result has also been
observed that there is decrement in electrical power from 1.61 W to 1.46 W at intensity 600 W/m2 and from 2.16 W to 1.51 W
at intensity 800 W/m2 for the same duration i.e. two hour and same mass flow rate. On the basis of this result it is concluded
that more electrical power is generated at higher intensity but there is more drop of electrical power with respect to time at
8. 251 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
higher intensity. Hourly variation of thermal gain at various intensities has been shown in Figure. 7. It has been seen that 27.5
% more thermal gain is achieved at 800 W/m2 with respect to 600 W/m2 at steady state. It can be seen that increase in time
duration will increase in the thermal output while decrease in the electrical efficiency. Experimental results shows that increase
in intensity will increase the thermal output. It has been observed that increase in intensity will increase the overall thermal
energy for MCSCT tile.
Figure 6. Variation of electrical power of single MCSCT tile at different intensity.
It is seen that 7.3 % more overall thermal energy is achieved when experiment is done at 700 W/m2 as compare to 600 W/m2
but when experiment is done at 800 W/m2 then increment in overall thermal energy is 21.1 % as compare to 700 W/m2 it is
due to more thermal gain is achieved at 800 W/m2 and electrical power is more unless same at all intensities at steady state.
Similarly trends have been experienced for overall exergy for the MCSCT tile as shown in Figure. 9
Figure 7. Variation of thermal gain of single MCSCT tile at different intensity.
Figure 8. Variation of overall energy of single MCSCT tile at different intensity
Figure 9. Variation of overall exergy of single MCSCT tile at different intensity
9. 252 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
5. Conclusions
The following conclusions have been drawn
• The thermal and electrical efficiency are 35.7 % and 12.4 % respectively for single MCSCT tile.
• This new present setup would have beneficial effect of permitting much less expensive installation for testing and
development. Hence the test procedure can be used by manufacturers for testing of different type of PV tiles and
combination of PV tiles in order to optimize its products for better efficiency
Nomenclature
Ac Area of solar cell, m2
b Width of the micro-channel, m
Cf Specific heat of air, J/kg K
dx Elemental length, m
dt Elemental time, sec
h Heat transfer coefficient, W/m2K
hbi Heat transfer coefficient from back of tedlar to ambient, W/m2K
hto Heat transfer coefficient from top glass cover to ambient, W/m2K
hT Heat transfer coefficient from back of tedlar to flowing air, W/m2K
hb ,in Heat transfer coefficient from back of insulation to ambient, W/m2K
U tca An overall heat transfer coefficient from solar cell to ambient through glass cover, W/m2K
U tcf An overall heat transfer coefficient from solar cell to flowing air through tedlar, W/m2K
U b An overall back loss heat transfer coefficient from flowing air to ambient, W/m2K
I ( t ) Incident solar intensity, W/m2
K Thermal conductivity, W/m K
L Length, m
N Number of micro-channel solar cell thermal (MCSCT) tile
.
m f Air mass flow rate in micro-channel, kg/s
&
Q u Useful heat, W
T Temperature, K
T Average temperature, K
U Overall heat transfer coefficient, W/m2K
v Velocity of air, m/s
η Efficiency at standard test condition (I(t)=1000 W/m2 and Ta=25oC)
o
V Velocity of fluid (air) flowing inside of channel, m/s
n pv Number of rows of micro-channel solar cell thermal (MCSCT) tile.
Greek letters
α Absorptivity
β Packing factor
τ Transmittivity
η Efficiency
ρ Density, kg/m3
Subscripts
a Ambient
c Solar cell
eff Effective
10. 253 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
T Tedlar
in Insulation
f Fluid(air)
fi Inlet fluid
fo Outgoing fluid
Appendix
In modeling equations, we used following relations for defining the design parameters, which are shown in Table 1
micro-channel solar cell thermal (MCSCT) tile:
α eff = τ g (α c − ηc )
hT = 2.8 + 3 × V
hto = 5.7 + 3.8 × v
hb ,in = 2.8 + 3 × v
−1
⎛L 1 ⎞
U tca =⎜ g + ⎟
⎜K ⎟
⎝ g hto ⎠
−1
⎛L 1⎞
U tcf = ⎜ T + ⎟
⎝ KT hT ⎠
U L = U b + U fa
References
Agrawal S. and Tiwari, G.N., 2011. Energy and exergy analysis of hybrid micro-channel photovoltaic thermal module, Solar
Energy, Vol. 85, pp. 356-370.
Bhargava AK, Garg HP, Agarwall RK. 1991. Study of a hybrid solar system-solar air heater combined with solar cells. Energy
Conversion and Management, Vol. 31, No. 5, pp. 471-479.
Cox III C.H., Raghuraman P. 1985. Design considerations for flat-plate photovoltaic/ thermal collectors. Solar Energy, Vol.
35, pp. 227–241.
Chow T.T., Hand J.W., Strachan P.A. 2003. Building-integrated photovoltaic and thermal applications in a subtropical hotel
building. Applied Thermal Engineering Vol. 23, pp. 2035–2049.
Chow T. T., 2010. A review on photovoltaic/thermal hybrid solar technology, Applied Energy, Vol. 87, pp. 365-369.
Chow TT, Chan ALS, Fong KF, Lin Z, He W, Ji J. 2009. Energy and exergy analysis of Photovoltaic thermal collector with
and without glass cover. Appl Energy, Vol. 86, No. 3, pp. 310–316.
Dubey S, Sandhu GS, Tiwari G.N. 2009. Analytical expression for electrical efficiencyof PV/T hybrid air collector. Applied
Energy, Vol. 86, No. 5, pp. 697-705.
Duffie JA, Beckman WA. Solar Engineering of Thermal Processes. John Wiley and Sons, New York, 1991.
Erdil E, Ilkan M, Egelioglu F. 2008. An experimental study on energy generation with a photovoltaic (PV)– solar thermal
hybrid system. Energy, Vol. 33, pp. 1241-1245.
Evans DL. 1981. Simplified method for predicting PV array output, Solar Energy, Vol. 27, pp. 555-560.
Garg HP, Agarwall RK, Joshi JC. 1994. Experimental study on a hybrid photovoltaic thermal solar water heater and its
performance prediction. Energy Conversion and Management, Vol. 35, pp. 621-633.
Garg HP, Adhikari RS. 1997. Conventional hybrid photovoltaic/ thermal (PV/T) air heating collectors: Steady-state
simulation. Renewable Energy, Vol. 11, pp. 363–385.
Hegazy AA. 2000. Comparative study of the performances of four photovoltaic/ thermal solar air collectors. Energy
Conversion and Management, Vol. 41, pp. 861–881.
Huang B.J., Lin T.H., Hung W.C., Sun F.S., 2001. Performance evaluation of solar photovoltaic/thermal systems, Solar
Energy, Vol. 70, No. 5, pp. 443-448.
Kalogirou SA. 2001. Use of TRYNSYS for modelling and simulation of a hybrid PV thermal solar system for Cyprus.
Renewable Energy, Vol. 23, pp. 247- 260.
11. 254 Agrawal and Tiwari ./ International Journal of Engineering, Science and Technology, Vol. 3, No. 1, 2011, pp. 244-254
Kern Jr. EC, Russell MC. 1978. Combined photovoltaic and thermal hybrid collector systems. In: Proc. 13th IEEE
Photovoltaic Specialists, Washington DC, USA, pp. 1153–1157.
Lee WM, Infield DG, Gottschalg R. 2001. Thermal modelling of building integrated PV systems In: Proceedings of 17th PV
Solar Energy Conference. Munich, 22–26 October, pp. 2754–2757.
Nayak S. , Tiwari G.N.,.2008. Energy and Exergy analysis of photovoltaic/thermal integrated with a solar greenhouse, Energy
and Buildings, Vol. 40, pp. 2015-2021.
Prakash, J. 1994. Transient analysis of a photovoltaic-thermal solar collector for co-generation of electricity and hot air/water.
Energy Conversion and Management, Vol. 35, pp. 967-972.
Radziemska E., 2009 Performance analysis of a photovoltaic-thermal integrated system, Int. Journal of Photoenergy, pp. 1-6.
Sopian K, Liu HT, Kakac S, Veziroglu TN. 2000. Performance of a double pass photovoltaic thermal solar collector suitable
for solar drying systems. Energy Conversion and Management, Vol. 41, No. 4, pp. 353-365.
Schott T. 1985. Operational temperatures of PV modules. In: Proceedings of 6th PV Solar Energy Conference, pp. 392-396.
Tiwari A, Sodha MS, Chandra A, Joshi JC. 2006. Performance evaluation of photovoltaic thermal solar air collector for
composite climate of India. Solar Energy Materials and Solar Cells, Vol. 90, No. 2, pp. 175-189.
Tiwari A, Dubey S, Sandhu G.S., Sodha M.S., Anwar S.I., 2009. Exergy analysis of integrated photovoltaic thermal solar
water heater under constant flow rate and constant collection temperature modes, Vol. 86, pp. 2592-2597..
Tiwari A, Sodha MS. 2006. Performance evaluation of solar PV/T system: An experimental validation. Solar Energy, Vol. 80,
No. 7, pp. 751-759.
Tiwari GN. 2004. Solar Energy: Fundamentals, Design, Modeling and Applications. Narosa Publishing House, New Delhi.
Zondag, H.A., de Vries, D.W. de, van Helden, W.G.J. ,van Zolengen, R.J.C. and steenhoven, A.A., 2002. The thermal and
electrical yield of a PV-thermal collector. Solar Energy, Vol. 72, No. 2, pp. 113-128.
Biographical notes
Sanjay Agrawal received B. E. from Madan Mohan Malviya engineering college, Gorakhpur, UP, India, M.Tech from U.P. technical university, Lucknow,
UP, India and presently pursuing Ph.D. from Indian Institute of Technology Delhi, India. He is a Reader in the Department of electrical and electronics
engineering, G.L.A. university, Mathura, India. Presently he is on leave from G.L.A. University, Mathura His areas of research interest are solar thermal,
photovoltaics, heat and mass transfer, exergy, CO2 mitigation, climate change and carbon trading.He is a Graduate memeber of IE (India).
Dr. G.N. Tiwari received postgraduate and doctoral degrees in 1972 and 1976, respectively, from Banaras Hindu University (B.H.U.) He is a Professor in the
centre for energy studies, Indianl Institute of Technology Delhi, India. He has more than 35 years of experience in teaching and research. His research interest
in the field of Solar Energy Applications are solar distillation, water/air heating system, greenhouse technology for agriculture as well as for aquaculture,
Earth to air heat exchanger, passive building design and hybrid photovoltaic thermal (HPVT) systems, climate change, energy security, etc. He has guided
about 55 Ph.D. students and published over 450 research papers in journals of repute. He has authored twenty books associated with reputed publishers. He is
a co-recipient of 'Hariom Ashram Prerit S.S. Bhatnagar' Award in 1982. Professor Tiwari has been recognized both at national and international levels. Dr.
Tiwari was Editor of International Journal of Agricultural Engineering for the duration of three years (2006-2008). He is Associate Editor for Solar Energy
Journal (SEJ) in the area of Solar Distillation since 2007. He. He is also Editor of International Journal of Energy Research. Prof. G.N.Tiwari has been
conferred “Vigyan Ratna” by Govt. of U.P., India on March 26, 2008 and Valued Associated Editor award by J. of Solar Energy. He has organized SOLARIS
2007, third international conference on "Solar Radiation and Day lighting" held at IIT Delhi, New Delhi, India from February 7 to 9, 2007. He is also
president of Bag Energy Research Society (BERS:www.bers.in) which is responsible for energy education in rural India. His current area of research includes
Multi-criteria Decision-Making, Quality Engineering, Assembly Line Balancing, Group Technology, Neural Networks, and Non-traditional Optimization and
Simulation. He has published more than fifty papers in referred international journals. He has also presented more than one hundred research articles in
national and international conferences. He has written few books related to his research work. He is currently dealing with few projects sponsored by
government of India.
Received January 2011
Accepted March 2011
Final acceptance in revised form May 2011