Solar Thermal Engineering
A. Naseri; M. Fazlikhani; M. Sadeghzadeh; A. Naeimi; M. Bidi; Seyyed H. Tabatabaei
Abstract
In this paper, a novel CO2 transcritical power cycle which is driven by solar energy integrated by a cryogenic LNG recovery unit is investigated. In the proposed cycle, the condenser unit of the CO2 power cycle is replaced by a Stirling engine. Thermodynamic and exergy analyses are carried out to evaluate ...
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In this paper, a novel CO2 transcritical power cycle which is driven by solar energy integrated by a cryogenic LNG recovery unit is investigated. In the proposed cycle, the condenser unit of the CO2 power cycle is replaced by a Stirling engine. Thermodynamic and exergy analyses are carried out to evaluate the performance of the presented system. Furthermore, in order to investigate the impact of utilization of Stirling engines instead of conventional condenser units, the proposed cycle is compared with the typical CO2 power cycle. The results show that employing the Stirling engine decrease the exergy destruction from 17% in the typical cycle to 8.85%. In addition, the total generated power of the novel system is considerably boosted up about 15 kW in off-peak times and more than 20 kW in the peak time. Moreover, integration of the Stirling engine also decreases LNG mass flow rate. Therefore, the required heat exchanger area in the LNG heater is also lowered.
H. Pourderogar; H. Harasii; R. Alayi; Seyed H. Delbari; M. Sadeghzadeh; A.R. Javaherbakhsh
Abstract
This paper aims to determine the optimal performance characteristics of a solar tracking system in order to maximize the power generation through using the MOPSO algorithm. Considering the sun path during a day, the necessity of using solar tracking systems to achieve the maximum power output from photovoltaic ...
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This paper aims to determine the optimal performance characteristics of a solar tracking system in order to maximize the power generation through using the MOPSO algorithm. Considering the sun path during a day, the necessity of using solar tracking systems to achieve the maximum power output from photovoltaic (PV) panels has been investigated. The solar tracking system allows PV arrays to follow sunlight all day long. The unidirectional tracking system follows the sun path, thereby optimizing the angular motion of PV arrays relative to the sun resulting in higher power generation. To evaluate the performance of a PV system, the total solar radiation was calculated first for both fixed and unidirectional tracking systems. Analyzing the results indicates that for June 20th the power generation of the PV module equipped with a unidirectional tracker is 35% higher than the fixed PV module. The optimal value of the declination angle, Azimuth, and arrays’ tilting angles in a unidirectional tracking system calculated using the MOPSO algorithm are , and respectively.
Systems with Low Energy Consumption
Seyyed M. Mirlohi; M. Sadeghzadeh; R. Kumar; Mehdi Ghassemieh
Abstract
In this research, a plan to implement a zero-energy building (ZEB) for a hot and dry climate region of Iran (Yazd) is introduced and a comparison with a typical house of that climate is performed. Based on climate conditions, several active or passive methods are available in order to create a balance ...
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In this research, a plan to implement a zero-energy building (ZEB) for a hot and dry climate region of Iran (Yazd) is introduced and a comparison with a typical house of that climate is performed. Based on climate conditions, several active or passive methods are available in order to create a balance between energy supply and demand, namely improving wall insulations by using efficient heating/cooling devices, using solar energy, utilizing energy storage devices, and etc. Here, the SketchUp software is employed to present the plot of the selected building. In addition, one of the interfaces of Energy plus software called "BEOpt" is used for performing energy and economic analyses on the fast-constructed and pre-fabricated schemes. Considering the equipment’s world price, the results demonstrate that the zero-energy building scheme in selected climate conditions is applicable and the payback period is estimated to be about 5.5 years. In addition, replacing the typical buildings with a ZEB will decrease carbon dioxide emissions by about 27.4 metric tons/yr.