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    Improving performance of a photovoltaic panel by pin fins: a theoretical analysis

    , Article Iranian Journal of Science and Technology - Transactions of Mechanical Engineering ; Volume 44, Issue 4 , 2020 , Pages 997-1004 Sedaghat, A ; Karami, M. R ; Eslami, M ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2020
    As efficiency of PV modules decreases with temperature rise, cooling methods can increase the power output and efficiency. One of the strategies for this purpose is passive cooling by implementing fins to the backside of a module. In the present study, annual energy output of a 50 W panel is analytically calculated in two unfinned and pin-finned cases based on hourly meteorological data for Shiraz, Iran. The results show that with the installation of 2-cm, 4-cm and 6-cm aluminum pin fins with finned-to-total-backside-area ratios of 0.17, 0.27 and 0.55, the power output increases by 1.24–4.16%, compared to the unfinned case. This increase is equivalent to 1.04–3.50 kWh more electrical energy... 

    Experimental investigation of the effect of using thermosyphon heat pipes and vacuum glass on the performance of solar still

    , Article Energy ; Volume 75 , 2014 , pp. 501–507 ; ISSN: 03605442 Jahangiri Mamouri, S ; Gholami Derami, H ; Ghiasi, M ; Shafii, M. B ; Shiee, Z ; Sharif University of Technology
    A desalination system consumes energy for production of freshwater. Since the solar energy is a low-cost, environmentally clean, and available energy throughout the world, it could be the best source of energy for such systems. In this work, a modified desalination system is presented which uses advantages of thermosyphon heat pipes as a fast and high performance thermal conducting device, and at the same time, employs the advantages of evacuated tube collectors (ETCs) which are flexible and have high performance in adverse weather conditions. Results show considerable increase in the production rate of desalinated water and system efficiency with a maximum production rate of 1.02 kg/(m2 h)... 

    Thermoeconomic analysis and multi-objective optimization of an integrated solar system for hydrogen production using particle swarm optimization algorithm

    , Article Journal of Thermal Engineering ; Volume 7, Issue 4 , 2021 , Pages 746-760 ; 21487847 (ISSN) Keykhah, S ; Assareh, E ; Moltames, R ; Taghipour, A ; Barati, H ; Sharif University of Technology
    Yildiz Technical University  2021
    This study aims to investigate the hydrogen production process using an integrated system based on solar energy. This system includes an evacuated tube collector to absorb solar energy as input energy of the system. A parametric analysis was conducted to determine the most important design parameters and evaluate these parameters' impact on the system's objective functions. For identifying the optimum system conditions, multi-objective optimization was performed using particle swarm optimization (PSO) algorithm. The results obtained from the parametric analysis show that an increment in the collector mass flow rate and the turbine inlet temperature, as well as a decrement in the collector... 

    Utilization of hybrid nanofluids in solar energy applications: A review

    , Article Nano-Structures and Nano-Objects ; Volume 20 , 2019 ; 2352507X (ISSN) Ahmadi, M. H ; Ghazvini, M ; Sadeghzadeh, M ; Alhuyi Nazari, M ; Ghalandari, M ; Sharif University of Technology
    Elsevier B.V  2019
    Hybrid nanofluids have several advantages compared with the conventional types due to their modified properties. Their enhanced thermophysical and rheological properties make them more appropriate for solar energy systems. In this review paper, an overview of solar energy systems is represented, and afterwards, applications of hybrid nanofluids in various solar technologies, especially solar thermal, are reviewed. Comparison between the nanofluidic systems, and the conventional ones is performed in order to gain a deeper insight into the advantages of using nanofluids. According to the results of the reviewed studies, the most important reason for performance enhancement of nanofluidic solar... 

    Energy Consumption Mitigation in Buildings by Using Seasonal Energy Storage in Aquifers, Heat Pumps and Solar Energy

    , Ph.D. Dissertation Sharif University of Technology Ghaebi, Hadi (Author) ; Bahadorinejad, Mehdi (Supervisor) ; Saidi, Mohammad Hassan (Supervisor)
    The aim of this research has been to modeling and optimization of steam injected gas turbine with inlet air cooling using absorption chiller. The whole system consists of compressor, combustion chamber, turbine, heat recovery steam generator, absorption chiller and cooling coil. The tasks carried out in this research include four points of view. The thermodynamic, exergetic, thermo-economic and environmental points of view are considered along modeling and optimization process. Design variables including temperature of combustion chamber exhausted gas, pinch point temperature of heat recovery steam generator and steam injection flow rate. Finally this modeling and optimization process is... 

    Optimal Design of Active and Passive Solar Greenhouses Considering Climate Conditions

    , M.Sc. Thesis Sharif University of Technology Esmaeli, Homa (Author) ; Roshandel, Ramin (Supervisor)
    Increasing global demand for water, food, energy and the interdependency of these three nexuses increase the necessity of finding suitable solutions and making policies considering the impact of each nexus to the others. The aim of developing greenhouses is to produce high-quality food with high performance while the water consumption decrease. This comes along with huge amount of energy consumption. Solar greenhouse technology utilizes solar energy to decrease heating demand of greenhouse to zero. The greenhouse performance has a direct correlation with climate condition. This research has been conducted to present optimal design for solar greenhouses. Firstly, a solar passive design was... 

    How CdS nanoparticles can influence TiO2 nanotube arrays in solar energy applications?

    , Article Applied Catalysis B: Environmental ; Volume 162 , January , 2015 , Pages 210-216 ; 09263373 (ISSN) Qorbani, M ; Naseri, N ; Moradlou, O ; Azimirad, R ; Moshfegh, A. Z ; Sharif University of Technology
    Elsevier  2015
    In this study, titanium dioxide (TiO2) nanotube array (TNA) films are fabricated via anodization of titanium (Ti) sheet. After annealing, the films consisted of well ordered, vertically oriented TNAs of 125±6nm diameter, 38±3nm wall thickness, and 2.9±0.3μm in length. Cadmium sulfide (CdS) nanoparticles are deposited on the synthesized TNAs by sequential-chemical bath deposition (S-CBD) method with different immersion cycle (n) to produce heterogeneous TNA/CdS-n (n=10, 20 and 30) nanostructures. UV-visible absorption spectra of the samples revealed that the absorption edge of CdS modified TNAs was shifted to a higher wavelength with respect to the pure TNAs indicating band gap reduction of... 

    Moisture stability in nanostructured perovskite solar cells

    , Article Materials Letters ; 2018 ; 0167577X (ISSN) Malekshahi Byranvand, M ; Nemati Kharat, A ; Taghavinia, N ; Sharif University of Technology
    Elsevier B.V  2018
    Perovskite solar cells (PSCs) have attracted significant attention due to their excellent efficiency reaching 22.1% in just the past few years. Despite their high efficiency, the limited long-term stability of PSCs has to be overcome. Moisture environments has been recognized as a main degradation pathway of perovskite materials. This review summarizes recent studies about relationship of the stability of PSCs with moisture environment. We also discuss the current standard strategies for enhancing the stability of PSCs by modifying the properties of either the perovskite material itself or its interfaces. © 2018  

    Moisture stability in nanostructured perovskite solar cells

    , Article Materials Letters ; Volume 237 , 2019 , Pages 356-360 ; 0167577X (ISSN) Malekshahi Byranvand, M ; Nemati Kharat, A ; Taghavinia, N ; Sharif University of Technology
    Elsevier B.V  2019
    Perovskite solar cells (PSCs) have attracted significant attention due to their excellent efficiency reaching 22.1% in just the past few years. Despite their high efficiency, the limited long-term stability of PSCs has to be overcome. Moisture environments has been recognized as a main degradation pathway of perovskite materials. This review summarizes recent studies about relationship of the stability of PSCs with moisture environment. We also discuss the current standard strategies for enhancing the stability of PSCs by modifying the properties of either the perovskite material itself or its interfaces  

    Applications of thermal energy storage in solar organic rankine cycles: A comprehensive review

    , Article Frontiers in Energy Research ; Volume 9 , 2021 ; 2296598X (ISSN) Salem, M ; Fahim Alavi, M ; Mahariq, I ; Accouche, O ; El Haj Assad, M ; Sharif University of Technology
    Frontiers Media S.A  2021
    Organic Rankine Cycles (ORCs) are promising approaches for generating power from medium or low temperature heat sources. In this regard, ORCs can be used to indirectly produce power from solar energy. Due to intermittent nature of solar energy, storage unit should be coupled with solar ORCs to improve the output power and operating hours. In this article, studies on solar ORCs integrated with various types of storage units were reviewed; the main findings of such studies were extracted and provided. Based on the findings, several factors such as the temperature and pressure at the inlet of the turbine, as well as the operating condition affect the performance of solar ORCs with thermal... 

    Optimization of Hybrid Solar-Biomass based CCHP (Combined Cooling, Heating, and Power)Cycles

    , M.Sc. Thesis Sharif University of Technology Jamali, Navid (Author) ; Avami, Akram (Supervisor) ; Broushaki, Mehrdad (Supervisor)
    Solar power is a clean energy resource which has been known as an important renewable energy source; however, due to the high cost of installation and the need for energy storage systems in the absence of sunlight at night, it has not been used on a large scale till now. Using the combination of solar energy and biomass energy from agriculture and urban waste in a power plant may be regarded as a commercial option due to the removal of individual solar power energy storage costs. In this study, a hybrid solar-biomass power plant will be studied. Linear Fresnelin and parabolic through technologies in the solar section and combustion and gasification technologies were used in the biomass... 

    Seawater Purification System by Solar Energy

    , M.Sc. Thesis Sharif University of Technology Moradi Hemmat Abad, Mostafa (Author) ; Abbaspour Tehrani Fard, Majid (Supervisor)
    World population is increasing with a rapid paste while the availability of freshwater is becoming more scared. There is a severe lack of fresh water in the world today. Desalination of seawater is one of the significant options in hand to solve this problem. In this research a hybrid solar collector- high efficiency water purification system is introduced which can help to solve this problem with an interesting economic outlook. Renewable energies and desalination plants are two different technologies, which can be combined in various ways. The interface between the renewable energy system and the desalination system is met at the place/subsystem where the energy generated by the renewable... 

    Exergy and Thermoeconomic Analysis of a Hybrid System of Desalination and CCHP, Augmented by Solar Energy

    , Ph.D. Dissertation Sharif University of Technology Saraei, Alireza (Author) ; Abbaspour Tehrani Fard, Majid (Supervisor)
    The demand in water and energy for household, industrial and agricultural uses continue to grow. In recent years, many researches have been done on thermodynamic assessment and optimization of Combined Cooling, Heating and Power (CCHP) and desalination systems. The interesting and important point is the potential of combining CCHP and desalination systems by employing the solar power. The purpose of this study is exergy analysis and thermoeconomic optimization of a hybrid system of Multi-Effects Distillation desalination (MED) and CCHP, augmented by solar energy. The thermoeconomic analysis is carried out by Total Revenue Requirement (TRR) method. Properties of working fluid in hybrid MED... 

    Solar Concentrator Using Light Splitting Method for PV Systems

    , M.Sc. Thesis Sharif University of Technology Kiyaee, Soroush (Author) ; Saboohi, Yadollah (Supervisor) ; Moshfegh, Alireza (Co-Advisor)
    Given the population growth in the world and in dire need of electricity and to reduce pollution and moving toward sustainable development, renewable energy has special importance in the world. Iran, with 300 days of sunshine a year is one of the countries with high potential in the field of solar energy but for various reasons, solar energy has no significant role in our energy portfolio. Considering the purchase of solar power by the government, reduce solar electricity costs and payback time of the factors that could make greater use of this energy. In this projects using light splitting method, in addition to reducing cell area used, by removing a significant portion of the sun's rays... 

    Sizing and performance analysis of standalone hybrid photovoltaic/battery/hydrogen storage technology power generation systems based on the energy hub concept

    , Article International Journal of Green Energy ; Volume 14, Issue 2 , 2017 , Pages 121-134 ; 15435075 (ISSN) Homayouni, F ; Roshandel, R ; Hamidi, A. A ; Sharif University of Technology
    Taylor and Francis Inc  2017
    In this study, the optimal sizing and performance analysis of a standalone integrated solar power system equipped with different storage scenarios to supply the power demand of a household is presented. One of the main purposes when applying solar energy resource is to face the increasing environmental pollutions resulting from fossil fuel based electricity sector. To this end, and to compare and examine two energy storage technologies (battery and hydrogen storage technology), three storage scenarios including battery only, hydrogen storage technology only and hybrid storage options are evaluated. An optimization framework based on Energy Hub concept is used to determine the optimum sizes... 

    Modeling and Optimization of a Solar System with Phase Chang Materials storage

    , M.Sc. Thesis Sharif University of Technology Nekoonam, Saeed (Author) ; Rowshandel, Ramin (Supervisor)
    In this project a system of solar air collector and a storage tank containing of phase change materials has been modeled, examined and optimized. The collector model has been developed in the EES engineering software and also solar thermal potential has been calculated via MATLAB software and then imported to EES and with past air and ambient charectristics, the effective thermal temperature of solar air collector`s exhaust will be defined for six mid days of six cold months. In the coldest day of those six days storage model witch has been developed in MATLAB will be consumed to withdraw the models results and then system parameters go on a sensitivity analysis and a novel system goes for... 

    Simulation and Techno–Economical Analysis of an Improved Integrated Concentrated Photovoltaic/Organic Rankine Cycle System

    , M.Sc. Thesis Sharif University of Technology Moltames, Rahim (Author) ; Roshandel, Ramin (Supervisor)
    The combination of photovoltaic technology and Organic Rankine Cycle reduces the temperature of the solar panel and, on the other hand, generates separate electricity from excess heat. The reason for the use of the Organic Rankine Cycle is the low temperature of the heat source. It is not economical to use other cycles like steam Rankine cycle in low-temperature heat sources. To maximize the plant factor of the Organic Rankine cycle system, especially when there is not enough solar radiation, it is possible to utilize the flue gas heat recovery in office buildings and reduce the cost of electricity generation. In this project, the simulation of this system is carried out for the Energy... 

    Experimental Investigation of Double Wall Solar Still

    , M.Sc. Thesis Sharif University of Technology Favakeh, Amir Hossein (Author) ; Shafii, Mohammad Behshad (Supervisor) ; Sadrhosseini, Hani (Supervisor)
    Salt water is desalinated to produce fresh water suitable for human consumption or irrigation. Most of desalination methods require consuming large amounts of fossil fuels. Solar distillation is one of the best techniques from another available techniques for desalinating in small-scale brackish water. The main problem of these systems is the low rate of water production.Single basin solar still is a very simple solar device used for converting available brackish or waste water into potable water. This device can be fabricated easily with locally available materials. The maintenance is also cheap and no skilled labor is required. It can be a suitable solution to solve drinking water problem.... 

    Modeling and Optimization of a Solar Thermal Storage for Concentrating Solar Power Plants

    , M.Sc. Thesis Sharif University of Technology Shamsi, Hamid Reza (Author) ; Boroushaki, Mehrdad (Supervisor)
    One of the main components of any solar power plant is the heat storage. Implementing heat storage reduc-es the cost of power generation by increasing the capacity factor of the system. This Thesis aims to analyze the operation of heat storages by modeling latent heat
    storage. In this regard, an efficient method named "Method of Characteristics" is utilized. Models developed based on this method are possible to be used for comparison, sensitivity analysis, and optimization due to their low computation time. Sensitivity analysis was carried out based on various parameters such as void fraction, fiUer material size. Results show that using latent heat storage, storage c-apacity is... 

    A Novel Optimization Algorithm for Reliable Energy based on Wind, Solar and Fuel Cell

    , M.Sc. Thesis Sharif University of Technology Khayyamim, Tara (Author) ; Hajsadeghi, Khosro (Supervisor) ; Zabihollah, Abolghasem (Supervisor)
    Concerns like fuel cost, pollution and global warming has made it necessary to look for new energy solutions. Renewable and alternative energies have proven themselves to be helpful in this matter. Renewable energy(RE) is the energy that comes from natural resources such as sunlight, wind, rain, tides, waves and geothermal heat, which are naturally replenished at a constant rate. Renewable energies are environmentally friendly, not cheap at the beginning but naturally available in a constant rate and wide spread, unlike fossil fuels that are localized in the limited places. In this thesis in order to generate environmental friendly power we consider two renewable energy resources: wind and...