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- 实验方案
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Integrative modelling and optimisation of a desiccant cooling system coupled with a photovoltaic thermal-solar air heater
摘要： An integrated model of a desiccant cooling system with a hybrid photovoltaic thermal collector-solar air heater (PVT-SAH) was developed and coupled with a building model to enable a performance evaluation and optimisation of the system. A double pass PVT-SAH system that incorporates heat pipes was used to increase the air temperature of the PVT-SAH outlet in order to regenerate the desiccant in a desiccant wheel. The integrated model was then used to quantify the performance of the hybrid desiccant cooling system in terms of Solar Fraction (SF) and the Coe?cient of Performance (COP) and its response to the various sizes of PVT-SAH systems. The model outputs showed that the selection of the PVT-SAH design parameters can be critical in improving the system’s utilisation in a desiccant cooling process. For a commercial building case study in a hot and humid climate, the annual Solar Fraction and the electrical COP of the cooling system reached up to 96.6% and up to 19.8 respectively, when the design of the PVT-SAH was optimised. The optimal electrical COP was higher than those for non-optimal designs that ranged from 0.6 to 15.1. The minimum size of the PVT-SAH that is required for the hybrid desiccant cooling system to exceed a typical COP for commercial buildings (2.6–3.0) was found to be 0.35 m2 per m2 of the conditioned ?oor area.
关键词： Desiccant cooling system,Integrated modelling of solar desiccant systems,Photovoltaic thermal collector-solar air heater,Design optimisation
更新于2025-09-12 10:27:22
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Overall efficiency enhancement and cost optimization of semitransparent photovoltaic thermal air collector
摘要： A semitransparent photovoltaic‐thermal (PV/T) air collector can produce electricity and heat simultaneously. To maximize the thermal and overall efficiency of the semitransparent PV/T air collector, its availability should be maximum; this can be determined through a Markov analysis. In this paper, a Markov model is developed to select an optimized number of semitransparent PV modules in service with five states and two states by considering two parameters, namely failure rate (λ) and repair rate (μ). Three artificial neural network (ANN) models are developed to obtain the minimum cost, minimum temperature, and maximum thermal efficiency of the semitransparent PV/T air collector by setting its type appropriately and optimizing the number of photovoltaic modules and cost. An attempt is also made to achieve maximum thermal and overall efficiency for the semitransparent PV/T air collector by using ANN after obtaining its minimum temperature and available solar radiation.
关键词： availability,semitransparent,ANN,photovoltaic‐thermal (PV/T) air collector
更新于2025-09-12 10:27:22
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Progress of MWCNT, Al <sub/>2</sub> O <sub/>3</sub> , and CuO with water in enhancing the photovoltaic thermal system
摘要： Hybrid photovoltaic thermal system is an effective method to convert solar energy into electrical and thermal energy. However, its effectiveness is widely affected due to the high temperature of photovoltaic panel, and it can be minimized by employing nanofluids to the PV/T systems. In this research, the effect of various nanoparticles on the PV/T systems was studied experimentally. The nanofluids Al2O3, CuO, and multiwall carbon nanotube (MWCNT) were dispersed with water at different volume fractions of 0, 0.5, 1, 2.5, and 5 (vol%) using ultrasonication process. The effect of nanomaterials on viscosity and density was classified. All tests were carried out in an outdoor laboratory setup for calibrating the PV temperatures, thermal conductivity, electrical power, electrical efficiency, and overall efficiency. In addition, the energy analyses were also made to estimate the loss of heat owing to the nanofluids. Results show that use of the nanofluid increased the electric power and electrical efficiency of PV/T compared with water. Furthermore, MWCNT and CuO reduced the cell temperature by 19%. Consequently, the nanofluids MWCNT, Al2O3, and CuO produced the impressive values of 60%, 55%, and 52% increase in an average electrical efficiency than conventional PV. Particularly, the MWCNT produced superior results compared with other materials. It is evidently clear from the result that the introduction of the nanofluid increases the thermal efficiency without adding any extra energy to the system. Moreover, insertion of Al2O3, CuO, and MWCNT on PV/T system increases the exergy efficiency more than conventional PV module.
关键词： photovoltaic thermal system,solar energy,nanoparticles,nanofluid,exergy,hybrid PV/T collectors
更新于2025-09-12 10:27:22
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Effects of different greenhouse coverings on energy parameters of a photovoltaic–thermal solar system
摘要： The present study analyzed the power and heat supply of a small-scale greenhouse by a photovoltaic–thermal (PV/T) system while using three greenhouse coverings (glass, plastic and polycarbonate) and four water mass flow rates (0.016, 0.025, 0.033 kg/s and no-flow), with or without a solar tracker. The electrical efficiency results for PV (without mass flow) and PV/T (0.016, 0.025 and 0.033 kg/s) states indicated that the application of the PV/T system enhanced electrical efficiency by 21.5, 28.4 and 36.84% for the glass glazing, by 15.28, 25 and 34.79% for the plastic covering, and by 19.82, 26.67 and 40.25% for the polycarbonate covering, compared to the PV state. The highest overall efficiency was at 0.033 kg/s with 59.9% (glass), 54.56% (plastic) and 47.58% (polycarbonate), and the lowest overall efficiency was at 0.016 kg/s with 41.75% (glass), 32.94% (plastic) and 31.22% (polycarbonate). In general, due to the electrical and thermal energy requirements of greenhouses, it can be said that, in addition to producing electricity by PV/T systems, their significant thermal energy production compared to PV panels can also promote the use of such systems in the future.
关键词： Photovoltaic/thermal,Different greenhouse coverings,Electrical efficiency,Thermal efficiency
更新于2025-09-11 14:15:04
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Advanced Cooling Technologies and Applications || Development of Modular Cooling for Water-Cooled Photovoltaic Plant in Real Scale
摘要： This chapter evaluates module architectures and units of photovoltaic cooling systems, aiming to determine, select and design a modular system that can be applied in a real-scale photovoltaic power plant (PVPP) in order to enhance the yields of electricity production (entitled cooled photovoltaic plant). An analysis of the local climatic, geographic and solar conditions as well as construction, operational and maintenance aspects was carried out. Worldwide, there are three main types of cooled photovoltaic systems: PVT liquid and air collectors, PV ventilated with heat recovery and non-PVT systems. Based on the local weather conditions (tropical warm and dry) with both temperature and solar irradiation index being high, it results the PVT-liquid system to be more suitable in a scenario with available cooling fluid. We conclude that the best design and arrangement of the cooling system are of the type coil and multiple channel because they permit better rates of heat exchange between the cooling fluid and the PV module.
关键词： solar energy,cooling photovoltaic system,photovoltaic/thermal,PVPP,SFV
更新于2025-09-11 14:15:04
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Characteristics analysis of the photovoltaic thermal heat pump system on refrigeration mode: An experimental investigation
摘要： Photovoltaic thermal heat pump technology stands for the combination of solar heat pump technology and a photovoltaic system, which has the characteristics of tri-generation (heating, cooling, and electricity) to meet the building's energy requirement. In this paper, the dual-use photovoltaic thermal heat pump system was used and investigated experimentally with an emphasis on the refrigeration mode, which with the feature of the novel roll-bond photovoltaic thermal unit working as condenser directly. Moreover, renewable energy such as solar radiation and long-wave radiation are the main energy source of this system. The experimental investigation of the system comprising; 4 roll-bond photovoltaic thermal units, 1 horsepower heat pump unit and 600 L ice storage tank was carried out. The performance evaluation method and uncertainty analysis of the system was proposed and implemented along with the examination on the refrigeration performance and operating characteristics of the system. The results indicate that the proposed photovoltaic thermal heat pump system can achieve the refrigeration for building space cooling demand in summer with high performance and long-term stable operation. This study could provide a valuable reference for the photovoltaic thermal heat pump multi-generation system design and large-scale practical application in northern China.
关键词： Photovoltaic thermal heat pump,Experimental study,Refrigeration performance,PVT,Operation characteristics
更新于2025-09-11 14:15:04
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Multi-Party Energy Management and Economics of Integrated Energy Microgrid with PV/T and CHP system
摘要： Focusing on electricity and thermal energy requirement of contemporary buildings, a joint operation of photovoltaic thermal (PV/T) based prosumers and a Microturbine based combined heat and power (CHP) system has been presented to analyse the economics of grid-connected microgrid (MG) system. Bidirectional flow of electricity and heat model is considered and is optimally managed using price-based demand response (DR) scheme. Thermal storage is exploited to ward off the substantial amount of heat wastages that enhance the system's reliability during any disruption of microturbine. The objective functions of both prosumer and microgrid operator (MGO) are formulated as a profit maximization problem where they interact with each other on the basis of DR activity. To establish this strategic decision-making process, the system is modelled as a Stackelberg Equilibrium (SE) game, where MGO acts as a leader while PV/T prosumers act as a follower. The interaction or contribution of two players in a game is a problem of non-linear optimization which is solved by Differential Evolution (DE) algorithm. In the end, in a case study, it has been proved that the results are quite lucrative for the proposed model.
关键词： photovoltaic thermal (PV/T),Differential Evolution (DE),demand response (DR),Stackelberg Equilibrium (SE),microgrid (MG),combined heat and power (CHP)
更新于2025-09-10 09:29:36