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Exergoeconomic and enviroeconomic analysis of semitransparent and opaque photovoltaic (PV) panels: a comparative study
摘要： In present communication exergoeconomic and enviroeconomic analyses of two different stand-alone photovoltaic (PV) modules viz. semitransparent and opaque have been performed. The exergoeconomic examination is very useful way to investigate the correlation between capital cost and exergy losses. The enviroeconomic analysis describes the carbon dioxide mitigation by the system. The energy (electrical) produced annually by semitransparent and opaque PV panel is also evaluated. It is reported that the semitransparent panel shows better performance as for as energy saving are concern. Environmental cost reduction is found to be 128.7 Rs. /year and 125.95 Rs. /year for semitransparent and opaque PV modules, respectively.
关键词： PV module,Exergoeconomic,exergy,enviroeconomic
更新于2025-09-23 15:19:57
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Energy, exergy and efficiency of four photovoltaic thermal collectors with different energy storage material
摘要： Hybrid photovoltaic thermal (PV/T) is a technology with many variations and designs. The aim of this unit is cooling down PV temperature while producing hot water. In this paper, different PV/T designs are compared in terms of energy, exergy and efficiency. Data from experiments and numerical calculations conducted at Bangi, Malaysia was used for the comparisons. The proposed systems were tested in outdoor conditions. The designs in question are water-based PV/T, water-based PV/T with PCM tank, nanofluid-based PV/T with nano-PCM tank and conventional PV module. Effect of mass flow rate and solar irradiance are emphasized in this paper. The highest thermal efficiency, thermal energy and electrical exergy produced are found for PV/T with nanofluids and nano-PCM with around 72%, 14 kW and 76.152, respectively. All PV/T systems proposed exhibit better performance than the conventional PV module. These findings highlight the utility of PV/T technology and its massive potential to energize and popularize the solar energy field.
关键词： Nanofluids,PV/T,Nano-PCM,Exergy,Efficiency
更新于2025-09-19 17:13:59
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Thermodynamics assessment on cooling photovoltaic modules by phase change materials (PCMs) in critical operating temperature
摘要： Increasing the temperature of photovoltaic (PV) cells decreases their electricity generation. The use of phase change materials (PCMs) is one of the most common methods for controlling the rate of increasing the temperature of PV cells. This research focuses on thermodynamic analysis of PV/PCM systems with and without fins in maximum operating temperature of PV modules (85 °C). Polyethylene glycol 600 (PEG-600) and paraffin, with different melting points, have been studied experimentally as PCM in an indoor condition. Moreover, the effect of using fins was investigated. For this critical temperature, the results showed that using paraffin could be better for controlling the temperature of PV cells, due to its closer melting point with the module temperature. In the case of fins included, the temperature differences of 28.0 °C and 8.8 °C between the case of paraffin + fin and the case of PEG 600 + fin in comparison with the conventional PV module were measured, respectively. At this critical temperature condition, the output power of a PV module cannot exceed the half of its nominal power. The exergy efficiency of the paraffin + fin case was measured to 4.2% more than the conventional one. Also, entropy generation was calculated and reduction up to 5% was shown for paraffin + fin in comparison with the conventional one. Moreover, variations of the Rayleigh number for proposed cases are calculated too.
关键词： Energy,Critical operating temperature,Entropy,Photovoltaic,PCM,Exergy
更新于2025-09-19 17:13:59
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Analysis of the Day-ahead Deviation Plan and Research on the Real-time Scheduling of Photovoltaic Greenhouses Based on Exergy Theory
摘要： For the correction problem of day-ahead plan deviation caused by energy prediction deviation in day-ahead scheduling stage of photovoltaic greenhouses, an exergy analysis method is used to propose the deviation model of heat required for photovoltaic greenhouses. Based on the deviation model, a real-time optimization scheduling model is established. The deviation model not only considers the non-negligible exergy loss during heating process of pipes, but also considers the di?erence between heat and thermal exergy a?ected by the actual indoor temperature. The goal of the real-time scheduling model is to minimize the absolute value of the di?erence between the energy supply and demand prediction deviation to be corrected and the adjustment of multi-form energy storage and electric loads, so that develop the real-time adjustment plan of energy storage and electric loads. The analysis results of the actual photovoltaic greenhouse show that of the heat required by a greenhouse based on the exergy theory calculation, the exergy loss of the heating process accounts for about 10%–20% of the total thermal exergy required and it cannot be ignored, so the calculation results can re?ect the actual heat required more accurately and the greenhouse temperature is more suitable for plant growth. Moreover, the proposed real-time scheduling model can correct the deviation of the day-ahead plan and improve local consumption. The promotion ratio can reach 7%. Finally, the farmers’ electricity purchases cost is reduced. Thereby the e?ectiveness of the proposed heat deviation model and real-time scheduling model is veri?ed.
关键词： photovoltaic greenhouse,real-time scheduling,exergy,deviation of the day-ahead plan
更新于2025-09-19 17:13:59
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Simulation-Based Exergy Analysis of Large Circular Economy Systems: Zinc Production Coupled to CdTe Photovoltaic Module Life Cycle
摘要： The second law of thermodynamics (2LT) helps to quantify the limits as well as the resource efficiency of the circular economy (CE) in the transformation of resources, which include materials, energy, or water, into products and residues, some of which will be irreversibly lost. Furthermore, material and energy losses will also occur, as well as the residues and emissions that are generated have an environmental impact. Identifying the limits of circularity of large-scale CE systems, i.e., flowsheets, is necessary to understand the viability of the CE. With this deeper understanding, the full social, environmental, and economic sustainability can be explored. Exergy dissipation, a measure of resource consumption, material recoveries, and environmental impact indicators together provide a quantitative basis for designing a resource-efficient CE system. Unique and very large simulation models, linking up to 223 detailed modeled unit operations, over 860 flows and 30 elements, and all associated compounds, apply this thermoeconomic (exergy-based) methodology showing (i) the resource efficiency limits, in terms of material losses and exergy dissipation of the CdTe photovoltaic (PV) module CE system (i.e., from ore to metal production, PV module production, and end-of-life recycling of the original metal into the system again) and (ii) the analysis of the zinc processing subsystem of the CdTe PV system, for which the material recovery, resource consumption, and environmental impacts of different processing routes were evaluated, and the most resource-efficient alternative to minimize the residue production during zinc production was selected. This study also quantifies the key role that metallurgy plays in enabling sustainability. Therefore, it highlights the criticality of the metallurgical infrastructure to the CE, above and beyond simply focusing on the criticality of the elements.
关键词： Thermoeconomics,Geometallurgy,Process simulation,Jarosite,Circular economy,Sustainability,Digital twin,Exergy,CdTe photovoltaic (PV) modules
更新于2025-09-16 10:30:52
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Exergy analysis of a photovoltaic thermal system with earth water heat exchanger cooling system based on experimental data
摘要： In this paper, an attempt has been made to evaluate the experimental exergetic assessment of photovoltaic/thermal (PV/T) system with novel cooling technology termed as earth water heat exchanger (EWHE) cooling. The exergetic efficiency is calculated by considering of exergy destructions and exergy losses. It was observed that the total exergetic efficiency of PV/T is the function of mass flow rate of cooling water for a given solar radiation. The exergetic efficiency of the PV/T system is calculated in three ways, Case I: excluding exergy losses, Case II: including both exergy losses and exergy destructions and Case III: considering only exergy destructions. The results of all the cases were compared and it was found out that the exergetic efficiency of PV/T in Case III was more than the other two cases and it lies between 24.95% to 25.85% and 24.30% to 25.57% for the flow rate of 0.017 kg/s and 0.025 kg/s respectively.
关键词： earth water heat exchanger,EWHE,photovoltaic,PV/T,exergy,solar energy
更新于2025-09-16 10:30:52
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A novel solar system integrating concentrating photovoltaic thermal collectors and variable effect absorption chiller for flexible co-generation of electricity and cooling
摘要： Traditional single effect and double effect absorption chillers have relatively narrow working temperature ranges, which limits their application of solar systems. This study proposes a novel solar system integrating concentrating photovoltaic and thermal collectors, and a variable effect absorption chiller, for more flexible and efficient co-generation of electricity and cooling. In this study, variable effect chiller was optimized, showing that three working modes, combined with optimized control, make variable effect chillers a superior choice to the single effect and double effect types. Then, dynamic simulations of the solar co-generation system were performed, in order to study the effects of temperature control on system performance. The results showed that, a high turn-off temperature for the chiller generally results in higher cooling power, shorter working hours for the chiller, and in some cases, a frequent on–off cycling of chiller. With the increase in working temperature level, the cooling exergy efficiency increases, but total exergy efficiency decreases due to the photovoltaic cell’s degraded performance. The total exergy efficiency is approximately 32%–33%. A larger difference between turn-on and turn-off temperatures delays the start time of the chiller while ensuring the full use of solar energy. By adjusting the temperature control strategy, the novel solar co-generation system can offer a cooling-electricity ratio from 1.4 to 2.0, which is capable of meeting the demands in many cases. The proposed system offers flexible co-generation of cooling and electricity.
关键词： Exergy efficiency,Solar cooling,Concentrating photovoltaic and thermal (CPV/T) collector,Dynamic simulation,Variable effect absorption refrigeration cycle
更新于2025-09-16 10:30:52
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Experimental study and exergy analysis of photovoltaic-thermoelectric with flat plate micro-channel heat pipe
摘要： Effective cooling of the photovoltaic can enhance electrical conversion efficiency of a photovoltaic system. The combination of photovoltaic and thermoelectric generator provides unique advantages because of their complementary characteristics. In addition, hybrid photovoltaic-thermoelectric can utilize a wider solar spectrum thereby harvesting more energy from the sun. Heat pipes are passive devices that can transfer heat efficiently over a long distance. Therefore, this study presents an experimental investigation and exergy analysis of a photovoltaic-thermoelectric with flat plate micro-channel heat pipe. The experiment is performed in a laboratory using a solar simulator and water-cooling is used for the thermoelectric generator. The effect of thermoelectric load resistance, micro-channel heat pipe back insulation and solar radiation on the performance of the hybrid system is presented and a comparison with a photovoltaic only system is provided. Results show that the hybrid system provides an enhanced performance compared to the photovoltaic only system and absence of insulation behind the micro-channel heat pipe enhances electrical performance of the hybrid system. Furthermore, results show the feasibility of the hybrid system for generating electricity and small hot water. This study will provide valuable guidance for design of photovoltaic-thermoelectric systems with heat pipe and verifies the feasibility of such systems.
关键词： Thermal management,Power generation,Exergy,Micro-channel heat pipe,Photovoltaic-thermoelectric
更新于2025-09-16 10:30:52
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Energy and exergy efficiencies enhancement analysis of integrated photovoltaic-based energy systems
摘要： Integrated energy systems (IESs) take advantage of the complementarity of their subsystems to improve the overall system functionality, sustainability and performance. Presently, the cost of the recovery of thermodynamic losses from photovoltaic modules has not been addressed. In this study, novel energy and exergy efficiencies enhancement analysis (EEEEA) is proposed for the study of the implications of recovering the conversion and usage losses from a photovoltaic (PV) module. Four evolutionary IES were analysed: a PV-Battery (System 1); a Photovoltaic-thermal (PV/T)-Battery (System 2); a PV-Battery-Electrolyser-Fuel cell (System 3) and a PV/T-Battery-Electrolyser-Fuel cell (System 4). Actual solar radiation and temperature data coupled with synthesised data were applied. Results show that both the energy and exergy efficiencies of System 2 upgraded by 27.89% and 5.42%, respectively, over System 1. The energy and exergy efficiencies of System 3 degraded by 3.11% and 4.10%, respectively, over System 1; whereas the energy and exergy efficiencies of System 4 degraded by 21.92% and 7.72%, respectively, over System 2. Furthermore, the thermodynamic efficiencies of the IESs did not naturally upgrade with system complexity. The EEEEA can help scientists, engineers and policymakers to analyse IESs with a parent-offspring relationship in order to establish the optimum efficiency and thermo-economics.
关键词： Photovoltaics,Integrated energy systems,Energy and exergy analysis,Exergy centred design,Distributed systems
更新于2025-09-12 10:27:22
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AIP Conference Proceedings [AIP Publishing XIAMEN-CUSTIPEN WORKSHOP ON THE EQUATION OF STATE OF DENSE NEUTRON-RICH MATTER IN THE ERA OF GRAVITATIONAL WAVE ASTRONOMY - Xiamen, China (3–7 January 2019)] XIAMEN-CUSTIPEN WORKSHOP ON THE EQUATION OF STATE OF DENSE NEUTRON-RICH MATTER IN THE ERA OF GRAVITATIONAL WAVE ASTRONOMY - Exergy efficiency study case of photovoltaic/thermal hybrid cooling refrigeration system using organic fluid mixtures
摘要： At present, much interest is being shown in hybrid absorption refrigeration cycles driven by low temperature heat sources, such as solar energy or low-grade waste-heat. In the present work, an exergetic investigation of a novel configuration double-lift absorption/compression refrigeration system is developed. The potential of the organic mixture (R236fa/DMAC) in the low grade heat pump is discussed. In this paper, a modeling and simulation of the proposed configuration is presented. The ammonia-water system was used for comparison purposes. The results show that the performances of the proposed configuration are improved significantly when using the above mentioned organic mixture. Coefficient of performance of the cycle with R236fa/DMAC is 15% higher than with ammonia/water. Exergetic performances of the system are also improved by about 10% with the use of the proposed new mixture. The most important result given in this study is that the above system operates at low generator temperatures between 50°C and 80°C, which makes it a good alternative of the ammonia-water systems in the low grade heat refrigeration field. The use of such an organic fluid makes it possible to adapt the machine to sources of low energy value, among the possible solutions it was considered to install a hybrid photovoltaic unit that will meet the electrical needs of the heat pump. A simulation was also done to consolidate the results. Results of such a system show that the energy demand of absorption / compression refrigeration machines can be insured by about 80 % by solar energy. The proposed model is efficient in predicting the performance of the machine at different working conditions such as: temperature variation of the generator and evaporator, change in climatic conditions... To conclude, this study will allow making an economic optimization, an approximation on the lifetime as well as the annual production capacity of the unit.
关键词： hybrid heat pump,exergy analysis,organic absorbent,photovoltaic
更新于2025-09-12 10:27:22