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Investigation on gel polymer electrolyte-based dye-sensitized solar cells using carbon nanotube
, Article Ionics ; May , 2018 , Pages 1-7 ; 09477047 (ISSN) ; Khanmirzaei, M. H ; Lu, S. C ; Ramesh, S ; Ramesh, K ; Sharif University of Technology
Institute for Ionics
2018
Abstract
A new poly (acrylonitrile) (PAN)-based gel polymer electrolyte (GPE) is fabricated to study the effect of carbon nanotube (CNT) on dye-sensitized solar cell (DSSC) efficiency. The GPEs are examined using electrochemical impedance spectroscopy (EIS) to analyze ionic conductivity. A maximum of 4.45 mS cm−1 ionic conductivity is achieved at room temperature with incorporation of 11 wt.% CNT. Performance of DSSC is examined with a solar simulator, and the highest energy conversion efficiency of 8.87% is achieved with the addition of 11 wt.% CNT. All GPE samples are found to follow Arrhenius model with temperature-dependent ionic conductivity testing. Structural properties are also characterized...
Optimization of CuIn1-XGaXS2 Nanoparticles and Their Application in the Hole-Transporting Layer of Highly Efficient and Stable Mixed-Halide Perovskite Solar Cells
, Article ACS Applied Materials and Interfaces ; Volume 11, Issue 34 , 2019 , Pages 30838-30845 ; 19448244 (ISSN) ; Marandi, M ; Khosroshahi, R ; Malekshahi Byranvand, M ; Dehghani, M ; Zad, A. I ; Tajabadi, F ; Taghavinia, N ; Sharif University of Technology
American Chemical Society
2019
Abstract
Inorganic hole-transport materials (HTMs) have been frequently applied in perovskite solar cells (PSCs) and are a promising solution to improve the poor stability of PSCs. In this study, we investigate solution-processed copper indium gallium disulfide (CIGS) nanocrystals (NCs) as a dopant-free inorganic HTM in n-i-p type PSCs. Moreover, Cs0.05(MA0.17-FA0.83)0.95Pb(I0.83Br0.17)3 mixed-halide perovskite with proper crystalline quality and long-time stability was utilized as the light-absorbing layer under ambient conditions. To optimize the cell performance and better charge extraction from the perovskite layer, the Ga concentration in the Cu(In1-XGaX)S2 composition was changed, and the X...
Investigation on gel polymer electrolyte-based dye-sensitized solar cells using carbon nanotube
, Article Ionics ; Volume 25, Issue 1 , 2019 , Pages 319-325 ; 09477047 (ISSN) ; Khanmirzaei, M. H ; Lu, S. C ; Ramesh, S ; Ramesh, K ; Sharif University of Technology
Institute for Ionics
2019
Abstract
A new poly (acrylonitrile) (PAN)-based gel polymer electrolyte (GPE) is fabricated to study the effect of carbon nanotube (CNT) on dye-sensitized solar cell (DSSC) efficiency. The GPEs are examined using electrochemical impedance spectroscopy (EIS) to analyze ionic conductivity. A maximum of 4.45 mS cm −1 ionic conductivity is achieved at room temperature with incorporation of 11 wt.% CNT. Performance of DSSC is examined with a solar simulator, and the highest energy conversion efficiency of 8.87% is achieved with the addition of 11 wt.% CNT. All GPE samples are found to follow Arrhenius model with temperature-dependent ionic conductivity testing. Structural properties are also characterized...
A new trigeneration system for power, cooling, and freshwater production driven by a flash-binary geothermal heat source
, Article Renewable Energy ; Volume 148 , 2020 , Pages 31-43 ; Vajdi, M ; Rostamzadeh, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Among different types of geothermal processing used in the energy conversion systems, flash-binary geothermal can be the best scenario for high-temperature geothermal sources. Reviewing the available literature it can be found that the flash-binary geothermal power plants have a great potential to be extended to trigeneration systems, nonetheless they have received less attention. In this regard, a new trigeneration system for freshwater, power, and cooling production is devised using a flash-binary geothermal heat source at 170°C. In this devised trigeneration system, a humidification-dehumidification (HDH) unit is used as a binary cycle. Another merit of the devised trigeneration system is...
Robust optimization of renewable-based multi-energy micro-grid integrated with flexible energy conversion and storage devices
, Article Sustainable Cities and Society ; Volume 64 , 2021 ; 22106707 (ISSN) ; Habibifar, R ; Moradi, M ; Khoshjahan, M ; Nojavan, S ; Jermsittiparsert, K ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This paper presents a new model for optimal scheduling of renewable-based multi-energy microgrid (MEM) systems incorporated with emerging high-efficient technologies such as electric vehicle (EVs) parking lots, power-to-gas (P2G) facility, and demand response programs. The proposed MEM is equipped with wind energy, multi-carrier energy storage technologies, boiler, combined heat and power unit, P2G, EVs, and demand response with the aim of total operational cost minimization. Meanwhile, the system operator can participate in three electricity, heat, and gas market to meet local demands as well as achieve desired profits through energy exchanges. The proposed MEM is exposed to high-level...
Gas and Electrcicity Networks Co-Planning in Microgrid Generations
, M.Sc. Thesis Sharif University of Technology ; Fotuhi-Firuzabad, Mahmud (Supervisor) ; Rajabi-Ghahnavieh, Abbas (Co-Advisor)
Abstract
As a long-established approach, the electricity and natural gas networks have been operated and planned independently. Nevertheless, in recent years there has been a significant progress in energy conversion technologies in microgrids, thus making the electricity and gas networks more connected on the costumers’ side and also enabling users to utilize each of the carriers interchangeably. This increasing correlation between the two networks has led us to a new approach called co-planning of electricity and natural gas networks.This thesis aimed to take a closer look at this new approach and tried to study different aspects of it. Based on the concept of useful energy, a new approach has been...
Degradation Based Framework for Long-term Optimization of Energy Conversion Systems. Case Studies: Solid Oxide Fuel Cell Gas Turbine
, Ph.D. Dissertation Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
The energy systems efficiency is a great issue confront power plants professionals. Besides using high-tech components in power plants, plant operation optimization can significantly improve energy efficiency and economic performance, as efficiency of plant components generally depends on operating conditions. In addition, system preventive maintenance can reduce plant operation and failure costs, however it is also costly when done frequently. Therefore, optimizing operating conditions and preventive maintenance intervals can minimize the expected total cost of plant due to operation, failures and preventive maintenances. In recent years, the use of optimization models to determine plant...
Power System Load Frequency Control in the Presence of Wind Turbines
, M.Sc. Thesis Sharif University of Technology ; Ranjbar, Ali Mohammad (Supervisor)
Abstract
This study presents the application of the doubly fed induction generator (DFIG) to reduce the frequency deviation and improve frequency of a power system. This has been done by proposing a wind turbine model and a new fuzzy controller. The fuzzy controller has been suggested to change the speed of the wind turbine rotor and modify the impacts of wind speed fluctuations on the output power. The fuzzy controller parameters are optimized using the genetic algorithm (GA) to achieve the appropriate transient response. A smart controller is combined with fuzzy controller to optimize the usage of wind turbine’s kinetic energy. Furthermore, the DFIG with the proposed controller participates in the...
Feasibility Study of Re-Design of the Wells Turbine for Small Amplitude Ocean Waves Energy Conversion to Electricity by Analytical Method and Numerical Simulation
, M.Sc. Thesis Sharif University of Technology ; Taeibi Rahni, Mohammad (Supervisor) ; Abbaspour, Madjid (Supervisor)
Abstract
In this research, the feasibility of the usage of the Wells turbine for direct conversion of the hydro-mechanical energy of the surface waves is studied via analytical and numerical methodologies. The results produced, showed for the first time that the Wells turbine can be employed for such waves directly and the performance variables are quite reasonable and even efficient considering low cost of HKWT system and abundant availability of those waves. For the low-frequency waves, the turbine is tested for different wave velocities to discover the best angular velocity of the rotor in terms of performance and the rotational velocity of 300 RPM has been found to be the optimum amount. Further,...
Design of a hybrid Ocean Thermal Energy Conversion with Solar Thermal Energy (OTEC-STE) system for energy production(case study: Oman sea region)
, M.Sc. Thesis Sharif University of Technology ; Abbaspour Tehrani Fard, Majid (Supervisor)
Abstract
The ocean thermal energy conversion system is one of a variety of renewable marine energy that is made up of a thermodynamic cycle, and it uses the difference between the temperature of hot water at the ocean surface and cold water at the depths of the ocean to generate electricity. The closed cycle is one type in which the system uses a working fluid which its boiling point less than the boiling point of water. Increasing the temperature of the fluid inlet in the cycle increases the system efficiency, which has been applied in this study to increase the efficiency of the OTEC system. The required energy to increase this temperature has been achieved by adding a solar collector to this...
Design and Simulation of a Spar_Buoy Wave Energy Converter Using Piezoelectric Materials
, M.Sc. Thesis Sharif University of Technology ; Tabeshpour, Mohammad Reza (Supervisor) ; Abbaspour, Madjid (Supervisor)
Abstract
Nowdays, the world’s need for energy from renewable sources is increasing due to the excessive use of non - renewable resources and the pollution of the environment. Energy converters are classified into three general types: electromagnetic, electrostatic, and piezoelectric, in which piezoelectric materials are used in converters that convert mechanical energy into electrical energy (and vice versa). In the last decade there has been extensive research into the use of these materials for self-charging of low consumption electrically-powered devices such as sensors. For this purpose, in this study, a new method for harvesting electrical energy from the sea using piezoelectric elements is...
Study of Ion Transport from the Two-Dimensional Structure of MXene
, M.Sc. Thesis Sharif University of Technology ; Esfandiar, Ali (Supervisor)
Abstract
Reverse electrodialysis-based membranes are one of the most promising approaches to osmotic energy production. However, conventional reverse electrodialysis membranes have high strength and insufficient mass transfer, which leads to low power density and efficiency. In recent decades, the transport of ions at the nanoscale for the manufacture of reverse electrodialysis machines has attracted much attention. Compared to conventional devices, power density and energy conversion efficiency increase dramatically due to space constraints and electrostatic interactions at the nanoscale. Lamellar nanostructures, which can be easily fabricated by stacking two-dimensional nanosheets, may be a...
Design and implementation of current based vector control model of brushless doubly fed induction generator
, Article 2013 3rd International Conference on Electric Power and Energy Conversion Systems, EPECS 2013 2013, Article number 6713022 ; 2013 ; 9781479906888 (ISBN) ; Gorginpour, H ; Hajbabaei, A ; Ouni, S ; Oraee, H ; Sharif University of Technology
2013
Abstract
This paper is aimed at proposing a current based vector control model of the brushless doubly fed induction generator, modelling the presented control method, as well as implementing the proposed algorithm by DSP. In order to achieve the purpose, by presenting a detailed coupled circuit model of BDFIG, the vector model and then the current based vector control algorithm of the mentioned machine are acquired. The way of independent control of torque and power, and also the structure of speed controller amongst the proposed control model are discussed. Additionally, the concepts behind the proposed structure of the speed control system and the way of determining the model parameters are...
Stable operation of grid connected Cascaded H-Bridge inverter under unbalanced insolation conditions
, Article 2013 3rd International Conference on Electric Power and Energy Conversion Systems, EPECS 2013 2013 ; 2013 ; 9781479906888 (ISBN) ; Javadian, V ; Iman Eini, H ; Yadollahi, M ; Sharif University of Technology
2013
Abstract
This paper presents a single-phase Cascaded H-Bridge (CHB) inverter for photovoltaic applications. The proposed control strategy permits the optimum control of each string of PV panels in different insolation conditions. Based on the presented mathematical analysis, an analytic constraint is derived to check the stable operation of the inverter. A modified MPPT control strategy is also proposed based on this new condition. This strategy enhances the stability margins of the system by changing the operating point of some PV arrays. In this approach, the extracted power from high power cell is reduced to prevent instability issue and to avoid injection of highly distorted current into the...
A new fault tolerant scheme for cascaded H-Bridge multilevel converter
, Article 2013 3rd International Conference on Electric Power and Energy Conversion Systems, EPECS 2013 ; 2013 ; 9781479906888 (ISBN) ; Noroozi, N ; Shahbazi, M ; Zolghadri, M ; Oraee, H ; Sharif University of Technology
2013
Abstract
Multilevel converters are mainly used in high power applications (usually more than a few hundred kW). It is therefore important that they can continue working under faulty condition. In this paper, a new method is proposed to improve performance of CHB inverter under faulty condition. The proposed method will be compared with existing methods in term of voltage availability. The converter is simulated in Simulink and the results are provided. These results confirm the effectiveness of the proposed scheme, and are in accordance with the theoretical results
Using the direct simulation Monte Carlo method to study the effect of wall temperature variation on gas mixing evolution through micro T-mixers
, Article 11th International Energy Conversion Engineering Conference ; 2013 ; Sabouri, M ; Lekzian, E ; Schneider, G. E ; Sharif University of Technology
2013
Abstract
In this work, we study the gas mixing behavior in a micro T-mixer using the direct simulation Monte Carlo (DSMC) method. The gas mixing process is monitored through a T-mixer, which is fed by two different CO and N2 gases; flowing into the T-mixer through the upper and lower inlets. We investigate the effects of axial and lateral wall temperature gradients on the mixing evolution at different rarefaction levels. The achieved results show that any temperature difference between the channel walls would result in an increase in mixing length for the chosen wall temperature gradient ranges and the studies pressure cases. Our observations show that a positive temperature gradient toward the...
Supercritical synthesis and characterization of graphene-pbs quantum dots composite with enhanced photovoltaic properties
, Article Industrial and Engineering Chemistry Research ; Volume 54, Issue 30 , 2015 , Pages 7382-7392 ; 08885885 (ISSN) ; Tavakoli, M. M ; Outokesh, M ; Shafiekhani, A ; Simchi, A ; Sharif University of Technology
American Chemical Society
2015
Abstract
Lead sulfide quantum dots (PbS QDs) were decorated onto a graphene surface in a semi-core-shell structure using supercritical ethanol. The temperature of ethanol played significant role in controlling size and agglomeration of QDs as well as the extent of reduction of graphene. Average size of the QDs was estimated by transmission electron microscopy to be around 3.96 nm and by quantum models to be about 4.34 nm. PbS QDs prepared at 330 °C were of high purity, and the yield was 99%. Instrumental and chemical analyses demonstrated formation of a strong bond between PbS QDs and graphene, through a Pb-O-C bridge. UV and photoluminescence measurements along with theoretical considerations...
Estimation of weibull parameters for wind energy application in Iran's cities
, Article Wind and Structures, An International Journal ; Volume 21, Issue 2 , 2015 , Pages 203-221 ; 12266116 (ISSN) ; Hannani, S. K ; Boroushaki, M ; Sharif University of Technology
Techno Press
2015
Abstract
Wind speed is the most important parameter in the design and study of wind energy conversion systems. The weibull distribution is commonly used for wind energy analysis as it can represent the wind variations with an acceptable level of accuracy. In this study, the wind data for 11 cities in Iran have been analysed over a period of one year. The Goodness of fit test is used for testing data fit to weibull distribution. The results show that this data fit to weibull function very well. The scale and shape factors are two parameters of the weibull distribution that depend on the area under study. The kinds of numerical methods commonly used for estimating weibull parameters are reviewed. Their...
Strategy deviation index as a new reactive market power indicator
, Article IET Conference Publications, 7 November 2010 through 10 November 2010, Agia Napa ; Volume 2010, Issue 572 CP , 2010 ; 9781849193191 (ISBN) ; Nourizadeh, S ; Ranjbar, A. M ; Sharif University of Technology
2010
Abstract
Reactive market power assessment is an important issue for ISOs and the regulators of the reactive power market. Due to the localized characteristics of reactive power as a technical support and its monopsonistic nature as an economic commodity, a vivid reactive market power index including market share, demand side and cost is not achieved yet. In this paper, a new reactive market power index is presented which is based on bidding strategy deviation of the GENCOs after establishing a uniform price auction reactive market. Not knowing others' offers to ISO, each unit faces a bidding strategy problem that is solved using game theory. Considering its production costs, the unit uses the...
Nanofluid-assisted gas to hydrate (GTH) energy conversion for promoting CO 2 recovery and sequestration processes in the petroleum industry
, Article Petroleum Science and Technology ; Volume 34, Issue 1 , 2016 , Pages 37-43 ; 10916466 (ISSN) ; Montazeri, V ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
In this work the enhancement of gas to hydrate conversion employing the nanographene oxide (NGO)-based nanofluid regarding CO2 capture and sequestration recovery is investigated. A new series of experiments are carried out at different pressures, temperatures, agitation intensities and NGO promoter concentrations by using a newly developed fully automated GTH (gas to hydrate) energy converter. According to the presented results at the 3 MPa and 275.15 K and in the presence of 30 ppm NGO, it is possible to reach a CO2 gas to hydrate conversion of 95% at a low impeller speed in less than 2.5 h, which is quite interesting from an energy consumption standpoint. The presented approach can have...