Advanced Energy Technologies
Sedigheh Sadegh Hassani; Leila Samiee
Abstract
In the present work, natural biomass and chemical materials were applied as the heteroatom resources for modifying the Porous Graphene (PG) structure by pyrolysis method at 900 ºC. The physical and chemical characterizatons were performed by means of Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller ...
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In the present work, natural biomass and chemical materials were applied as the heteroatom resources for modifying the Porous Graphene (PG) structure by pyrolysis method at 900 ºC. The physical and chemical characterizatons were performed by means of Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET), Raman Spectroscopy, N2 Adsorption-Desorption, and X-ray Photo-electron Spectroscopy (XPS). Furthemore, the behavior of the prepared materials was investigated by Cyclic Voltammetry (CV) and Rotating Disk Electrode (RDE). The obtained results indicated that doping of heteroatoms into the graphene framework was possible using a low-cost and environment-friendly biomass material as well as chemical sources. Moreover, one-step quarternary and tersiary co-doped graphene could be acheived using natural biomass. The prepared electrocatalysts using grape leaves and sulfur trioxide pyridine complex exhibit higher electrocatalytic performance as exampled which conducted the electrocatalyst in 4e- pathway and showed high stability in methanol solutions during the process, confirming their considerable potential to Oxygen Reduction Reaction (ORR) as an electro-catalyst. Moreover, the onset potential of Gl300G-900 and GSP 900 (0.93 V vs RHE) is almost equal to the Pt/C 20 wt % (0.99 V vs RHE). These optimal prepared cathodes (Gl300G-900 and GSP 900) in the Microbial Fuel Cell (MFC) test lead to considerable power densities of 31.5 mW m-2 and 30.9.mW m-2, which are close to 38.6 mW m-2 for the Pt/C 20 wt % cathode.
Renewable Energy Resources and Technologies
Mehdi Jahangiri; Fatemeh Karimi Shahmarvandi; Reza Alayi
Abstract
The use of small-scale Combined Heat and Power (CHP) to meet the electrical and thermal needs of buildings has grown exponentially and plans have been made in Iran to expand these systems. In view of the above, in the present work, for the first time, sensitivity analysis has been performed on the parameters ...
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The use of small-scale Combined Heat and Power (CHP) to meet the electrical and thermal needs of buildings has grown exponentially and plans have been made in Iran to expand these systems. In view of the above, in the present work, for the first time, sensitivity analysis has been performed on the parameters of natural gas price, annual interest rate, and the price of pollutant penalties. The CHP system studied included fuel cell, biomass generator, solar cell, wind turbine, and gas boiler. The techno-econo-enviro simulations were performed by HOMER software and the study area was Abadan. The use of a dump load to convert excess electricity into heat and heat recovery in a biomass generator and fuel cell are other advantages presented by the present work. The minimum Cost of Energy (COE) is 1.16 $/kWh. The results also showed that the use of biomass generators was economical when the annual interest rate was 30 %. The significant effect of using dump load on the required heat supply and the lowest price per kg of hydrogen produced equal to $ 35.440 are other results of the present work. In general, the results point to the superiority of solar radiation potential over wind energy potential of the study area and the prominent role of dump load in providing heat on a residential scale is clearly seen. Also, for the current situation, using biomass is not cost-effective.
Advanced Energy Technologies
Leila Samiee; Fatemeh Goodarzvand-Chegini; Esmaeil Ghasemikafrudi; Kazem Kashefi
Abstract
Some chemical processes, like the chlor-alkali industry, produce a considerable amount of hydrogen as by-product, which is wasted and vented to the atmosphere. Hydrogen waste can be recovered and utilized as a significant clean energy resource in the processes. This paper describes the thermodynamic ...
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Some chemical processes, like the chlor-alkali industry, produce a considerable amount of hydrogen as by-product, which is wasted and vented to the atmosphere. Hydrogen waste can be recovered and utilized as a significant clean energy resource in the processes. This paper describes the thermodynamic analysis of hydrogen recovery at an industrial chlor-alkali plant by installation of hydrogen boiler and alkaline fuel cell. In addition, emission reduction potentials for the proposed systems were estimated. However, the goal of this work is to analyze the techno-economic feasibility and environmental benefits of using utilization systems of hydrogen waste. The results showed that hydrogen boiler scenario could produce 28 ton/hr steam at pressure of 25 bar and temperature of 245 °C, whereas the alkaline fuel cell system could produce 7.65 MW of electricity as well as 3.83 m3/h of deionized water based on the whole surplus hydrogen. In comparison, the alkaline fuel cell scenario has negative IRR (Internal Return Rate) and NPV (Net Present Value) due to cheap electricity and high cost of capital investment. However, regarding the steam price, the hydrogen boiler project has reasonable economic parameters in terms of IRR and NPV. Therefore, the hydrogen recovery scenario is proposed to install a hydrogen boiler as a feasible and economic idea for steam production in our case. Furthermore, in terms of emission reduction, hydrogen boiler and alkaline fuel cell techniques can significantly reduce greenhouse gas emission by 49300 and 58800 tons/year, respectively, whereas other pollutants can also be reduced by 141 and 95 tons/year in hydrogen boiler and alkaline fuel cell scenarios, respectively.
Advanced Energy Technologies
Masoumeh Javaheri; Noushin Salman Tabrizi; Amir Rafizadeh
Abstract
Given that the catalyst and catalyst support properties have a key role to play in the electrochemical activity of fuel cells, in this research, the synergism effect of Pt and Ru nanoparticles reduced on catalyst support [synthesized Carbon Aerogel-Carbon Nanotube (CA-CNT)] was investigated. The catalyst ...
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Given that the catalyst and catalyst support properties have a key role to play in the electrochemical activity of fuel cells, in this research, the synergism effect of Pt and Ru nanoparticles reduced on catalyst support [synthesized Carbon Aerogel-Carbon Nanotube (CA-CNT)] was investigated. The catalyst support was synthesized by sol-gel method and the catalyst nanoparticles were reduced on catalyst support using impregnation and hydrothermal method. Different molar ratios of Pt:Ru (i.e., 0:1, 1:0, 3:1, 2:1, 1:1, 1:2, and 1:3) were applied as electrocatalysts for Methanol Oxidation Reaction (MOR). The electrochemical performance of these catalysts was compared with that of commercial Pt/C (20 % wt) for MOR. The physical properties of the synthesized catalyst support (CNT-CA) were studied using FESEM and BET techniques. Moreover, XRD and ICP analyses were employed for investigating each of the synthesized catalyst (Pt/CNT-CA and Ru/CNT-CA). The cyclic voltammetry and chronoamperometry methods were used to conduct electrochemical analysis. Research results indicated that synthesis methods were reliable. Moreover, CNT-CA had a proper performance as the catalyst support and the Pt:Ru with a 3:1 molar ratio was the best catalyst among all the synthesized catalysts for MOR.
Advanced Energy Technologies
Haleh Sadeghi; Iraj Mirzaei; Shahram Khalilaria; Sajad Rezazadeh; Mojtaba Rasouli Gareveran
Abstract
Among the renewable energy systems, fuel cells are of special significance about which more investigation is required. The principal goal of the present study is considering the effect of the geometry change on the fuel cell's performance. In this paper, a three-dimensional model of proton exchange membrane ...
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Among the renewable energy systems, fuel cells are of special significance about which more investigation is required. The principal goal of the present study is considering the effect of the geometry change on the fuel cell's performance. In this paper, a three-dimensional model of proton exchange membrane fuel cell has been numerically simulated with conventional cubic geometry. Afterwards, two brand-new cylindrical models have been proposed to compare and select the best model. The governing equations include mass, momentum, energy, species and electrical potential, which are discretized and solved using the method of computational fluid dynamics. The results obtained from numerical analyses were validated with those from experimental data, which showed acceptable agreement. For the above-mentioned models, changes in the species mass fraction, temperature, electric current density, and over-potential were analyzed in more detail. The results reveal that, in all three models, by decreasing the amount of cell voltage differences between the anode and the cathode, higher current density is produced, which leads to high input species consumption and, consequently, more water and heat generation. On the other hand, the four-channel cylindrical model is more efficient than the other two models and has shower pressure drop due to its shorter pathway. The results illustrated that, at V=0.6 )V(, the amount of the output current density in the four-channel model increased by approximately 18.4 %, compared to that in the other two models. Further, in this model, the material used in bipolar plates is less than that in the other models.
Advanced Energy Technologies
Ali Mostafaeipour; Mojtaba Qolipour; Hossein Goudarzi; Mehdi Jahangiri; Amir-Mohammad Golmohammadi; Mostafa Rezaei; Alireza Goli; Ladan Sadeghikhorami; Ali Sadeghi Sedeh; Seyad Rashid Khalifeh Soltani
Abstract
Fuel cells are potential candidates for storing energy in many applications; however, their implementation is limited due to poor efficiency and high initial and operating costs. The purpose of this research is to find the most influential fuel cell parameters by applying the adaptive neuro-fuzzy inference ...
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Fuel cells are potential candidates for storing energy in many applications; however, their implementation is limited due to poor efficiency and high initial and operating costs. The purpose of this research is to find the most influential fuel cell parameters by applying the adaptive neuro-fuzzy inference system (ANFIS). The ANFIS method is implemented to select highly influential parameters for proton exchange membrane (PEM) element of fuel cells. Seven effective input parameters are considered including four parameters of semi-empirical coefficients, parametric coefficient, equivalent contact resistance, and adjustable parameter. Parameters with higher influence are then identified. An optimal combination of the influential parameters is presented and discussed. The ANFIS models used for predicting the most influential parameters in the performance of fuel cells were performed by the well-known statistical indicators of the root-mean-squared error (RMSE) and coefficient of determination (R2). Conventional error statistical indicators, RMSE, r, and R2, were calculated. Values of R2 were calculated as of 1.000, 0.9769, and 0.9652 for three different scenarios, respectively. R2 values showed that the ANFIS could be properly used for yield prediction in this study
Somayeh Sarirchi; S. Rowshanzamir
Abstract
Nowadays, proton exchange membrane fuel cells (PEMFCs) are the most promising green energy conversion devices for portable and stationary applications. Traditionally, these devices were based onperfluoro-sulfonic acid electrolytes membranes, given the commercial name Nafion. Nafion is the mostused electrolyte ...
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Nowadays, proton exchange membrane fuel cells (PEMFCs) are the most promising green energy conversion devices for portable and stationary applications. Traditionally, these devices were based onperfluoro-sulfonic acid electrolytes membranes, given the commercial name Nafion. Nafion is the mostused electrolyte membrane till now; because of its high electrochemical properties such as high protonconductivity, good mechanical and chemical stability at fuel cell conditions, and .... However, its high cost, reducing the performance at temperature higher than 80℃, and low humidity are the majorproblems. Hydrocarbon polymers are encouraging alternative to Nafion, since they show the same oreven superior performance than Nafion at high temperature and low humidity by some modifications. Numerous researches confirmed that Sulfonated poly ether ether ketone (SPEEK) is a promising PEMbecause of its low-cost, low fuel cross over, and acceptable thermo-mechanical stabilities. However,suitable proton conductivity in SPEEKs is depending on the high degree of sulfonation (DS), whichcould deteriorate the mechanical properties of SPEEK membranes progressively at the high level. Toovercome this dilemma, various SPPEK-based hybrid/blend membranes are synthesized, and theeffects of the introduced fillers on their performance are investigated. The introduced inorganicparticles to the polymer membranes might be silica, zirconia, titania, heteropolyacids, carbonnanotubes, and.... Enhanced proton conductivity, water retention at high temperatures, and higherelectrochemical properties are mentioned as some advantages of incorporating inorganic material intothe polymer matrix. High thermo-mechanical resistance and electrochemical activities are supplied byinorganic moieties, while the organic parts supply plasticity and easier ductility at the low temperature.Indeed, SPEEK blends have a good potential to alter Nafion at the high temperature and/or relativelylow humidity. In this paper, the last advances in progress of SPEEK-based organic/inorganiccomposite membranes that perform truly under fuel cell conditions are discussed.
Mohammad Ameri; Mojtaba Yoosefi
Abstract
This paper presents sizing, energy management strategy, and cost analysis for a configuration consisting of solar photovoltaic (PV) panels, fuel cell (FC) storage system, and reverse osmosis (RO) desalination technology for combined power and fresh water production. In this system, PV is the main power ...
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This paper presents sizing, energy management strategy, and cost analysis for a configuration consisting of solar photovoltaic (PV) panels, fuel cell (FC) storage system, and reverse osmosis (RO) desalination technology for combined power and fresh water production. In this system, PV is the main power supply source; fuel cell is a storage system accompanied by Hydrogen production and storage devices; and for fresh water production, RO technology is considered as desalination unit. Energy production strategy, developed on the basis of solar irradiance, hourly electricity consumption, and daily fresh water demand to minimize the capacity of components. To this goal, a flowchart diagram is designed, and sizing method is modeled using MATLAB software based on this flowchart. Finally, economic analysis for co-production of fresh water and electricity is discussed, and results of sensitivity analysis for variations of net present value (NPV) cost in terms of different fuel cell storage system prices and different interest rates are presented. Results show that described energy management strategy causes the configuration to follow hourly electrical demand and daily fresh water requirement precisely, so that the total surplus energy production during a day is very little and negligible. Moreover, calculations show that the largest part of costs is due to the energy storage system. So, while the solar PV is the main energy source and solar irradiance in Khark Island more than Astara, the overall configuration cost is greater in Khark Island just because of greater energy storage system costs, nevertheless, using such energy storage systems is necessary due to intermittent inherent of solar energy.
