Renewable Energy Resources and Technologies
Mahdi Pourbafrani; Hossein Ghadamian; Mohammad Aminy; Meisam Moghadasi; Masoud Mardani; Mohammad Akrami; Amir houshang Khaki; Seyed Mohammad Kazem Sadr
Abstract
Evacuated tube solar collectors (ETSC) are widely utilized in both domestic and industrial solar water heaters (SWH) due to their commendable thermal performance and straightforward installation. However, a significant challenge associated with ETSC lies in the fact that half of the collector remains ...
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Evacuated tube solar collectors (ETSC) are widely utilized in both domestic and industrial solar water heaters (SWH) due to their commendable thermal performance and straightforward installation. However, a significant challenge associated with ETSC lies in the fact that half of the collector remains unexposed to sunlight. To overcome this limitation, parabolic reflectors can be employed as a viable solution. The primary objective of this study is to assess the performance of a compound parabolic concentrator (CPC) in conjunction with ETSC, taking into account a specific ratio between the areas of the CPC and ETSC. To achieve the desired configuration, the CPC was meticulously designed, fabricated, installed, and subsequently tested. Moreover, the energy performance of the absorber tube was scrutinized both with and without the integration of a parabolic trough collector. The experiments and data collection were conducted on two selected days for both the conventional ETSC device and the system incorporating the CPC. Meteorological data and operational conditions were measured and digitally stored for subsequent analysis. A noteworthy outcome of the study is the revelation that the energy efficiency of the system with a concentrator exhibited a notable improvement of 2.8% compared to the conventional system. Offline results further indicated that the performance of a single absorber tube with a concentrator increased by approximately 2.7 times when compared to the standard system. This suggests that the energy performance of the solar water heater, with a capacity of about 200 liters and featuring 7 absorber tubes with a concentrator, is comparable to that of the conventional system equipped with 18 absorber tubes.
Environmental Impacts and Sustainability
Mahdi Pourbafrani; Hossein Ghadamian; Meisam Moghadasi; Masoud Mardani
Abstract
In this research study, a cost-effective and reliable weather station using a microcontroller system containing instruments and sensors for measuring and recording ambient variables was designed, fabricated, and tested. The dataset recorded and stored in the meteorological system can be applied to conduct ...
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In this research study, a cost-effective and reliable weather station using a microcontroller system containing instruments and sensors for measuring and recording ambient variables was designed, fabricated, and tested. The dataset recorded and stored in the meteorological system can be applied to conduct various research in the field of energy and environment, especially in solar systems. Employing a microcontroller system reduces costs and provides special features such as accessing data on the web-based spreadsheets and adding control devices. In this system, meteorological information including solar radiation, air temperature, wind velocity, and air relative humidity is measured and saved in user-defined time intervals such as 30 seconds. The total cost for measuring equipment, sensors, and microcontroller along with a data logger is about 110 USD. To demonstrate the importance of using local meteorological data, in the vicinity of the case studies, the dataset provided by the local weather station was compared with the meteorological data of two nearby national stations for one month. The results revealed that the values reported by the national stations were different from the actual values measured by the local weather station. The deviations for solar radiation, wind velocity, air temperature and humidity values were at least 5, 9, 7%, and more than 100%, respectively.
Advanced Energy Technologies
Mahdi Shakouri; Alireza Noorpoor; Hossein Ghadamian
Abstract
This study presents an analytical method for quantifying the improvement of thermal energy performance of a building integrated photovoltaic double-skin façade. The system was suggested as a retrofit measure for an existing building in Tehran. The effect of thermal performance was analyzed through ...
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This study presents an analytical method for quantifying the improvement of thermal energy performance of a building integrated photovoltaic double-skin façade. The system was suggested as a retrofit measure for an existing building in Tehran. The effect of thermal performance was analyzed through computer-assisted developed codes using Engineering Equation Solver (EES) software. Three scenarios were defined and for each scenario, temperature and velocity profiles were provided through continuity, momentum, and energy equations. Given that the monocrystalline photovoltaic modules and the double-glazed windows are quite common in the current condition in Tehran, the authors considered them for analysis. A comparison of results is valuable for those cases that intend to select either glass or photovoltaic as the outer façade. The quantitative results illustrate that the proposed system would reduce the cooling demand in the summer case by 18.5 kilowatts, which is around 8.7 percent of the current cooling load. According to the results of the sensitivity analysis, both glass and photovoltaic façades were of greater efficiency in terms of energy saving in the summer. By increasing the ratio between the photovoltaic outer façade to the surface area of the glass section, the amount of energy saving due to the total cooling load reduction will increase. The results of the analysis showed that the application of the suggested system would reduce the thermal load by 2.1 percent in the winter season.
Advanced Energy Technologies
Mohammad Jafari; Hossein Ghadamian; Leila Seidabadi
Abstract
The study of the battery charge process as the only power storage agent in off-grid systems is of significant importance. The battery charge process has different modes, and the battery in these modes is dependent on the amount of charge. In order to charge the battery in off-grid systems, two charge ...
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The study of the battery charge process as the only power storage agent in off-grid systems is of significant importance. The battery charge process has different modes, and the battery in these modes is dependent on the amount of charge. In order to charge the battery in off-grid systems, two charge controllers including Pulse Width Modulation (PWM) and Maximum Power Point Tracker (MPPT) are commonly used. The charge rate (C-Rate) is different in these two models. Therefore, it is necessary to study the state of charge (SoC) in the PWM and MPPT models considerably. In this study, by using these two charge controller models, C-Rate is examined on portable and power plant scales. This research indicates that the PWM charge controller has better performance on the power plant scale than on the portable scale. The charging quality of the MPPT model is about 31 % and 7 % on portable and power plant scales, respectively, proved to be higher than that of the PWM charge controller. The PV panel performance has increased by 2 %-5 % through the application of the MPPT charge controller, compared with the PWM model. As the overall achievement of the experiment, according to the limitations of the MPPT charge controller, the PWM charge controller can be proposed on power plant scales, whereas the application of the MPPT model is appropriate for specific purposes.
Hossein Ghadamian; Hassan Ali Ozgoli; Mojtaba Baghban Yousefkhani; Foad Farhani
Abstract
Regenerative Fuel Cell (RFC) systems are used for the enhancement of sustainable energy aspect in conventional fuel cells. In this study, a photovoltaic-electrolyzer-fuel cell integrated cycle has been presented. The proposed system has been designed as a novel approach for alleviating the ...
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Regenerative Fuel Cell (RFC) systems are used for the enhancement of sustainable energy aspect in conventional fuel cells. In this study, a photovoltaic-electrolyzer-fuel cell integrated cycle has been presented. The proposed system has been designed as a novel approach for alleviating the restrictions on energy streams in the RFC systems. Modeling of the system has been performed from the mass and energy point of view, based on both theoretical and practical procedures. To generate electricity from hydrogen, a proton exchange membrane fuel cell, integrated with an electrolyzer system which works by solar energy, has been used. Optimized results of required photovoltaic area have shown significantdifferences between theoretical and practical approaches. Moreover, all efficiencies of two scenarios including total efficiency have been indicated and analyzed. The main advantage of this system in comparison with single solar systems, is generation of internal energy of about 2.3 kW for producing 1 kW electricity by the fuel cell.
