In this paper, we propose a thermal model of a hybrid photovoltaic/thermal concentration system. Starting from the thermal balance of the model, the equation is solved and simulated with a MATLAB code, considering air...In this paper, we propose a thermal model of a hybrid photovoltaic/thermal concentration system. Starting from the thermal balance of the model, the equation is solved and simulated with a MATLAB code, considering air as the cooling fluid. This enabled us to evaluate some of the parameters influencing the electrical and thermal performance of this device. The results showed that the temperature, thermal efficiency and electrical efficiency delivered depend on the air mass flow rate. The electrical and thermal efficiencies for different values of air mass flow are encouraging, and demonstrate the benefits of cooling photovoltaic cells. The results show that thermal efficiency decreases air flow rate greater than 0.7 kg/s, whatever the value of the light concentration used. The thermal efficiency of the solar cell increases as the light concentration increases, whatever the air flow rate used. For a concentration equal to 30 sun, the thermal efficiency is 0.16 with an air flow rate equal to 0.005 kg/s;the thermal efficiency increases to 0.19 with an air flow rate equal to 0.1 kg/s at the same concentration. An interesting and useful finding was that the proposed numerical model allows the determination of the electrical as well as thermal efficiency of the hybrid CPV/T with air flow as cooling fluid.展开更多
In order to utilize solar energy effectively and to achieve a higher electrical efficiency by limiting the operating temperature of the photovoltaic （PV） panel, a novel photovoltaic/thermal solar-assisted heat pump ...In order to utilize solar energy effectively and to achieve a higher electrical efficiency by limiting the operating temperature of the photovoltaic （PV） panel, a novel photovoltaic/thermal solar-assisted heat pump （PV/T-SAHP） system was proposed and constructed. The hybrid solar system generates electricity and thermal energy simultaneously. A distributed parameters model of the PWT-SAHP system was developed and applied to analyze the system dynamic performance in terms of PV action, photothermal action and Rankine cycle processes. The simulation results indicated that the coefficient of performance （COP） of the proposed PV/T-SAHP can be much better than that of the conventional heat pump. Both PV-efficiency and photothermic efficiency have been improved considerably. The results also showed that the performance of this PV/T-SAHP system was strongly influenced by the evaporator area, tube pitch and tilt angle of the PV/T evaporator, which are the key factors in PV/T-SAHP system optimization and PV/T evaporator design.展开更多
This paper introduces a temperature control technique for a medical herb dryer system. The technique fixes the drying temperature of the medical herbs at 40℃ even in cases of rapidly changing atmospheric conditions. ...This paper introduces a temperature control technique for a medical herb dryer system. The technique fixes the drying temperature of the medical herbs at 40℃ even in cases of rapidly changing atmospheric conditions. The control of the dryer temperature is achieved through using on/off controller. The designed dryer contains two systems, which are the thermal and electrical systems. The thermal system is designed to heat the drying air by using solar water collector and electric heater. While, the electrical system which contains a photovoltaic (PV)-WIND hybrid system is used to feed the different electrical loads of the dryer system. The control technique is investigated through simulation work by using MATLAB-SIMULINK. The simulation results indicate the high capability of the proposed technique in controlling the drying temperature, even in case of rapidly changing atmospheric conditions.展开更多
Intended for good productivity and perfect operation of the solar power grid a failure-free system is required.Therefore,thermal image processing with the thermal camera is the latest non-invasive(without manual conta...Intended for good productivity and perfect operation of the solar power grid a failure-free system is required.Therefore,thermal image processing with the thermal camera is the latest non-invasive(without manual contact)type fault identification technique which may give good precision in all aspects.The soiling issue,which is major productivity affecting factor may import from several reasons such as dust on the wind,bird mucks,etc.The efficient power production sufferers due to accumulated soil deposits reaching from 1%–7%in the county,such as India,to more than 25%in middle-east countries country,such as Dubai,Kuwait,etc.This research offers a solar panel soiling detection system built on thermal imaging which powers the inspection method and mitigates the requirement for physical panel inspection in a large solar production place.Hence,in this method,solar panels can be verified by working without disturbing production operation and it will save time and price of recognition.India ranks 3rd worldwide in the usage use age of Photovoltaic(PV)panels now and it is supported about 8.6%of the Nation’s electricity need in the year 2020.In the meantime,the installed PV production areas in India are aged 4–5 years old.Hence the need for inspection and maintenance of installed PV is growing fast day by day.As a result,this research focuses on finding the soiling hotspot exactly of the working solar panels with the help of Principal Components Thermal Analysis(PCTA)on MATLAB Environment.展开更多
Powering a moon base,especially keeping it warm during the long lunar night,is a big challenge.This paper introduces a photovoltaic/thermal(PV/T)system incorporating regolith thermal storage to solve the challenge of ...Powering a moon base,especially keeping it warm during the long lunar night,is a big challenge.This paper introduces a photovoltaic/thermal(PV/T)system incorporating regolith thermal storage to solve the challenge of power and heat provision for the lunar base simultaneously.The vacuum of space around the moon helps this system by reducing heat loss.During the moon's daytime,the system not only generates electricity but also captures heat.This stored heat in the regolith is then used at night,reducing the amount of equipment we need to send from Earth.The spectrally selective PV/T panels are designed to absorb a wide range of sunlight(0.3–2.5μm)while minimizing heat loss in the infrared range(3–30μm).Simulation results of the hybrid solar energy system indicate the average value of the overall efficiency is 45.9%,which relatively elevates 56.1%compared to the PV system.The launch mass of the proposed PV/T system is only 8.4%of a traditional photovoltaic-lithium battery system with the same amount of energy storage.And the total specific energy of the proposed system is 7.3 kWh kg^(-1),while that of the photovoltaic-lithium battery system is about 0.3 kWh kg^(-1).In summary,this study proposes an alternative combined heat and electricity supply system for the lunar base,which can greatly reduce the launch mass and free up load for other scientific research equipment.展开更多
文摘In this paper, we propose a thermal model of a hybrid photovoltaic/thermal concentration system. Starting from the thermal balance of the model, the equation is solved and simulated with a MATLAB code, considering air as the cooling fluid. This enabled us to evaluate some of the parameters influencing the electrical and thermal performance of this device. The results showed that the temperature, thermal efficiency and electrical efficiency delivered depend on the air mass flow rate. The electrical and thermal efficiencies for different values of air mass flow are encouraging, and demonstrate the benefits of cooling photovoltaic cells. The results show that thermal efficiency decreases air flow rate greater than 0.7 kg/s, whatever the value of the light concentration used. The thermal efficiency of the solar cell increases as the light concentration increases, whatever the air flow rate used. For a concentration equal to 30 sun, the thermal efficiency is 0.16 with an air flow rate equal to 0.005 kg/s;the thermal efficiency increases to 0.19 with an air flow rate equal to 0.1 kg/s at the same concentration. An interesting and useful finding was that the proposed numerical model allows the determination of the electrical as well as thermal efficiency of the hybrid CPV/T with air flow as cooling fluid.
基金the National Natural Science Foundation ofChina (No. 50708105)partly supported by the Natural ScienceFoundation of Anhui Province (No. 070414161), China
文摘In order to utilize solar energy effectively and to achieve a higher electrical efficiency by limiting the operating temperature of the photovoltaic （PV） panel, a novel photovoltaic/thermal solar-assisted heat pump （PV/T-SAHP） system was proposed and constructed. The hybrid solar system generates electricity and thermal energy simultaneously. A distributed parameters model of the PWT-SAHP system was developed and applied to analyze the system dynamic performance in terms of PV action, photothermal action and Rankine cycle processes. The simulation results indicated that the coefficient of performance （COP） of the proposed PV/T-SAHP can be much better than that of the conventional heat pump. Both PV-efficiency and photothermic efficiency have been improved considerably. The results also showed that the performance of this PV/T-SAHP system was strongly influenced by the evaporator area, tube pitch and tilt angle of the PV/T evaporator, which are the key factors in PV/T-SAHP system optimization and PV/T evaporator design.
文摘This paper introduces a temperature control technique for a medical herb dryer system. The technique fixes the drying temperature of the medical herbs at 40℃ even in cases of rapidly changing atmospheric conditions. The control of the dryer temperature is achieved through using on/off controller. The designed dryer contains two systems, which are the thermal and electrical systems. The thermal system is designed to heat the drying air by using solar water collector and electric heater. While, the electrical system which contains a photovoltaic (PV)-WIND hybrid system is used to feed the different electrical loads of the dryer system. The control technique is investigated through simulation work by using MATLAB-SIMULINK. The simulation results indicate the high capability of the proposed technique in controlling the drying temperature, even in case of rapidly changing atmospheric conditions.
文摘Intended for good productivity and perfect operation of the solar power grid a failure-free system is required.Therefore,thermal image processing with the thermal camera is the latest non-invasive(without manual contact)type fault identification technique which may give good precision in all aspects.The soiling issue,which is major productivity affecting factor may import from several reasons such as dust on the wind,bird mucks,etc.The efficient power production sufferers due to accumulated soil deposits reaching from 1%–7%in the county,such as India,to more than 25%in middle-east countries country,such as Dubai,Kuwait,etc.This research offers a solar panel soiling detection system built on thermal imaging which powers the inspection method and mitigates the requirement for physical panel inspection in a large solar production place.Hence,in this method,solar panels can be verified by working without disturbing production operation and it will save time and price of recognition.India ranks 3rd worldwide in the usage use age of Photovoltaic(PV)panels now and it is supported about 8.6%of the Nation’s electricity need in the year 2020.In the meantime,the installed PV production areas in India are aged 4–5 years old.Hence the need for inspection and maintenance of installed PV is growing fast day by day.As a result,this research focuses on finding the soiling hotspot exactly of the working solar panels with the help of Principal Components Thermal Analysis(PCTA)on MATLAB Environment.
基金supported by the National Natural Science Foundation of China(Grant Nos.52106276 and 52130601)Fundamental Research Funds for the Central Universities(Grant No.WK2090000038)the Joint research center for multi-energy complementation and conversion of USTC。
文摘Powering a moon base,especially keeping it warm during the long lunar night,is a big challenge.This paper introduces a photovoltaic/thermal(PV/T)system incorporating regolith thermal storage to solve the challenge of power and heat provision for the lunar base simultaneously.The vacuum of space around the moon helps this system by reducing heat loss.During the moon's daytime,the system not only generates electricity but also captures heat.This stored heat in the regolith is then used at night,reducing the amount of equipment we need to send from Earth.The spectrally selective PV/T panels are designed to absorb a wide range of sunlight(0.3–2.5μm)while minimizing heat loss in the infrared range(3–30μm).Simulation results of the hybrid solar energy system indicate the average value of the overall efficiency is 45.9%,which relatively elevates 56.1%compared to the PV system.The launch mass of the proposed PV/T system is only 8.4%of a traditional photovoltaic-lithium battery system with the same amount of energy storage.And the total specific energy of the proposed system is 7.3 kWh kg^(-1),while that of the photovoltaic-lithium battery system is about 0.3 kWh kg^(-1).In summary,this study proposes an alternative combined heat and electricity supply system for the lunar base,which can greatly reduce the launch mass and free up load for other scientific research equipment.
