Top PDF Development of an Integrated Reformer and Fuel Cell System for Portable Power Applications

Development of an Integrated Reformer and Fuel Cell System for Portable Power Applications

Development of an Integrated Reformer and Fuel Cell System for Portable Power Applications

Overall, there are many issues which cause durability concerns for HT-PEM fuel cells. It should be noted that except for the issues relating to the PA environment or high temperature operations, the majority of the degradation mechanisms described are present for all fuel cell types, and can largely be mitigated through material choices and specific operational strategies. For a practical system, these strategies must be balanced with size, weight, cost, durability, and user operability requirements. To summarize, the primary degradation mechanisms result from high cell potentials and high temperature operations. Mitigation strategies for a HT-PEM fuel cell that will impact the majority of durability concerns discussed are to keep the cell potential below 0.8 V, which will avoid carbon corrosion and Pt dissolution, and minimize high temperature operation beyond 200 o C as much as possible to avoid PA evaporation loss. The latter is particularly challenging when operating the fuel cell on reformate containing high concentrations of CO, as the effect of CO poisoning is greatly decreased at higher temperatures. Other mitigation techniques such as operating at high pressures may reduce the PA evaporation rate to acceptable levels. Like all fuel cell types, PA/PBI have their unique degradation challenges; however, when operating under the proper conditions, the studies discussed in this section show that PA/PBI membranes are capable of operating for several thousands of hours. How these operational protocols and strategies are translated into a physical system design are discussed throughout the rest of this dissertation.
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Challenges in Fabricating Solid Oxide Fuel Cell Stacks for Portable Applications: A Short Review

Challenges in Fabricating Solid Oxide Fuel Cell Stacks for Portable Applications: A Short Review

fabrication. Therefore, several earlier studies have conducted manufacturing cost analyses for several different SOFC production volumes and system sizes [33][34]. To summarize, the stack cost comprises cell cost (raw materials and production) and balance of stack cost (components surrounding each cell). Numerous studies and cost projections have been performed for automotive fuel cell systems [35] and combined heat and power applications [36]. Direct stack manufacturing costs are mainly modeled for large appliances, whose net electricity capacities range between 1-250 kWe. Overall stack manufacturing costs range from $166 kW/e to $5,387 kW/e for a 250 kWe system at 50,000 systems per year. [37]. Dubois et al. [38] performed a comparative and extensive cost study between the fabrication of protonic ceramic fuel cells (PCFC) and SOFC stacks and the study demonstrated the cell raw material cost for SOFCs is 35% lower compared to PCFCs. For the total cost stack, it is shown in Figure 6 that SOFC stack operating in methane fuel at 800 o C is estimated to be 27% lower than its PCFC counterpart operating at 500 o C whereas for low operating temperature fuel cell, PEMFC, the total cost stack is expected to be much lower than both PCFC and SOFC. Operating at a low temperature enables PEMFC to have a wide variety of material selection resulting in a lower material cost compared to
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Investigation of a Combined Heat and Power Fuel Cell System for Small Scale Residential Applications

Investigation of a Combined Heat and Power Fuel Cell System for Small Scale Residential Applications

There are many design considerations involved with the development of fuel cell systems; three possible designs are represented in Figures 1,2 and 3. Design option one includes a natural gas fuel cell system to supply the lights, appliances, and electric space cooling loads of the residence. The space heating loads will be supplied by a water-to-air heat exchanger. Design option one allows for a very small fuel cell system, and minimum equipment requirements. Because the fuel cell stack is an expensive component of the system, the overall price may be lower than the following designs.
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Modeling Design of Solid Oxide Fuel Cell Power System for Distributed Generation Applications

Modeling Design of Solid Oxide Fuel Cell Power System for Distributed Generation Applications

Fuel cells are static energy conversion devices that convert the chemical energy of fuel directly into dc electrical energy. Fuel cells have a wide variety of potential applications including micro power, auxiliary power, transportation, stationary power for buildings, and cogeneration applications. Fuel cells have various advantages compared to conventional power sources, such as internal combustion engines or batteries. Although some of the fuel cells’ attributes are only valid for some applications, most advantages are more general. However, there are some disadvantages facing developers and the commercialization of fuel cells as well. Fuel cells eliminate pollution caused by burning fossil fuels; the only by product is water. Since hydrogen can be produced anywhere where there is water and e lectricity, production of potential fuel can be distributed. The other advantages with fuel cells are as follows; Installation of smaller stationary fuel cells leads to a more stabilized and decentralized power grid, Fuel cells have a higher efficiency than diesel or gas engines, Most fuel cells operate noise less, compared to internal combustion engines, Low temperature fuel cells (PEM, DMFC) have low heat transmission which makes them ideal for military applications, Earning of carbon credits by using this fuel-cell technology. However, they are attributed to some of the drawbacks; Fuelling fuel cells is still a problem since the production, transportation, distribution and storage of hydrogen is difficult, Reforming hydrocarbons via reformer to produce hydrogen is technically challenging and not clearly environmentally friendly. Fuel cells are in general slightly bigger than comparable batteries or engines. However, the size of the units is decreasing. Some fuel cells are expensive.
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Integrated Movable System of Fuel Cell with Replaceable Fiber Bipolar Plate

Integrated Movable System of Fuel Cell with Replaceable Fiber Bipolar Plate

The power conditioning system provides regulated DC or AC power appropriate for the application [12,13]. It is the major component of fuel cell system. The output of fuel cell power is an unregulated DC voltage and needs to be conditioned in order to be of practical use. The power conditioner section converts the raw power into useable power for different applications. The power con- ditioning unit also controls the frequency of electricity and maintains harmony to an acceptable current from fuel cell to suit the electrical needs of the application. The general configuration of the system will be the buck converter followed by a fuel cell stack and then proc- essed by an inverter. The buck converter for the fuel cell will be operated in the voltage control mode. The block diagram of the power conditioner with the fuel cell con- trol strategies incorporated is shown in Figure 3. There are two separate control loops for dc/dc converter control and the dc/ac inverter control. The unregulated output voltage (DC 30 - 48 V) of fuel cell is fed to the dc/dc buck converter. Being unregulated, it has to be adjusted to a constant average value (36 V) by adjusting the duty ratio to the required valve. The voltage is bucked de- pending upon the duty ratio. The duty ratio of the buck converter is adjusted with the help of a fuzzy logic con- troller from PLC link and touch panel.
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Power Management of PV, BESS and Fuel Cell based Hybrid Power System

Power Management of PV, BESS and Fuel Cell based Hybrid Power System

Renewable energy sources (solar, wind, tidal, etc.) are attracting more attention as alternative energy sources as conventional fossil-fuel energy sources are diminishing and world-wide environmental concerns about global warming and acid deposition increase. Among them, photovoltaic (PV) solar energy systems are widely used as an important option in small-size applications and are the most promising candidate for research and development for large-scale use because the fabrication of less costly photovoltaic cells becomes a reality. PV energy systems find various applications for the household appliances, for data communications and telecommunications systems, for the soldiers in the remote missions, for solar cars, and even for electric aircrafts [1]-[3]. From an operational viewpoint, a photovoltaic panel may experience large variations of its output power under variable weather conditions, which may result in control problems. One method to overcome these problems is to integrate the PV power system with other power sources; for example, diesel generators [4], superconductive magnetic energy
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Power Quality Improvement of Fuel Cell Integrated With Grid System

Power Quality Improvement of Fuel Cell Integrated With Grid System

Although fuel cells have been around since 1839, it took 120 years until NASA demonstrated some of their potential applications in providing power during space flight. As a result of these successes, in the 1960s, industry began to recognize the commercial potential of fuel cells, but encountered technical barriers and high investment costs— fuel cells were not economically competitive with existing energy technologies. Since 1984, the Office of Transportation Technologies at the U.S. Department of Energy has been supporting research and development of fuel cell technology , and as a result, hundreds of Companies around the world are now working towards making fuel cell technology pay off. Just as in the commercialization of the electric light bulb nearly one hundred years ago, today’s companies are being driven by technical, economic, and social forces such as high performance characteristics, reliability, durability, low cost, and environmental benefits .
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Characterization of Pt  Au Core –Shell System for the Fuel Cell Applications

Characterization of Pt Au Core –Shell System for the Fuel Cell Applications

Direct methanol fuel cells (DMFCs) are currently the subject of extensive interest due to their promise as high efficiency power sources free of the problems of hydrogen storage and transport [2-4]. Moreover, the rate of methanol oxidation reaction (MOR) at the anode is one of the locating factors for DMFCs currently developed. Currently the catalyst of choice for MOR in acidic media is Pt, although the two primary obstacle of platinum, its high cost and low poisoning resistance, have yet to be completely attenuated. Therefore, one of the main goals of catalyst development for DMFCs is to modify the Pt catalyst in order to decrease its cost while increasing its poisoning resistance and efficiency [5-7].
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Power Upgrading by MICROBIAL FUEL CELL

Power Upgrading by MICROBIAL FUEL CELL

Future scope: MFC designs need improvements before a marketable product will be possible. Both the issues identified above and the scale-up of the process remain critical issues. Most of the designs Reviewed here cannot be scaled to the level needed for a large wastewater treatment plant which requires hundreds of cubic meters of reactor volume. Either the intrinsic conversion rate of MFCs will need to be increased, or the design will need to be simplified so that a cost-effective, large scale system can be developed. Designs that can most easily be manufactured in stacks, to produce increased voltages, will be useful as the voltage for a single cell is low. In the long term more dilute substrates, such as domestic sewage, could be treated with MFCs, decreasing society‟s need to invest substantial amounts of energy in their treatment. A varied array of alternative applications could also emerge, ranging from biosensor development and sustained
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Dynamic Performance of Fuel Cell Power Module for  Mobility Applications

Dynamic Performance of Fuel Cell Power Module for Mobility Applications

Fuel cell powered vehicles have been developed as another alternative to internal combustion engine powered vehicles for some applications including passenger cars, buses, trains, motorcycles, forklifts, electric wheelchairs, electric trolleybuses, medical carts, military engines, personal sports craft, mobility devices and other self propelled equipment. Up to now, many researches have focused on the development of the power module in the Fuel cell vehicles (FCVs) and the components of these systems such as membranes, bipolar plates, and electrodes. However, our work in this study focuses on operating the integrated fuel cell power module system efficiently for various operating conditions such as pressure, relative humidity and operating modes. In our validation we have utilized PEMFC single cell, with active area geometry 16 cm 2 and of 120 cm 2 . Some results obtained in our study shown significant performance indica-
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Recent Development in Fuel Cell as an Alternate Fuel

Recent Development in Fuel Cell as an Alternate Fuel

This new type of fuel cell is based on a ceramic electrolyte material that exhibits high protonic conductivity at elevated temperatures. PCFCs share the thermal and kinetic advantages of high temperature operation at 700 degrees Celsius with molten carbonate and solid oxide fuel cells, while exhibiting all of the intrinsic benefits of proton conduction in PEM and phosphoric acid fuel cells. The high operating temperature is necessary to achieve very high electrical fuel efficiency with hydrocarbon fuels. PCFCs can operate at high temperatures and electrochemically oxidize fossil fuels directly to the anode. This eliminates the intermediate step of producing hydrogen through the costly reforming process. Gaseous molecules of the hydrocarbon fuel are absorbed on the surface of the anode in the presence of water vapor, and hydrogen atoms are efficiently stripped off to be absorbed into the electrolyte, with carbon dioxide as the primary reaction product. Additionally, PCFCs have a solid electrolyte so the membrane cannot dry out as with PEM fuel cells, or liquid can’t leak out as with PAFCs.
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DEVELOPMENT OF NOVEL NANOMATERIALS FOR HIGH- PERFORMANCE AND LOW-COST FUEL CELL APPLICATIONS

DEVELOPMENT OF NOVEL NANOMATERIALS FOR HIGH- PERFORMANCE AND LOW-COST FUEL CELL APPLICATIONS

Platinum or platinum alloys are commonly used as the catalyst in PEMFCs [2-4], where it catalyzes oxygen reduction reaction (ORR) at the cathode and fuel (including hydrogen and methanol) oxidation reaction at the anode [5,6]. Various carbon materials, including carbon black (CB) [7,8], carbon nanofibers (CNFs) [9], and carbon nanotubes (CNTs) [10,11], are being widely used catalyst supports due to their high surface area for the dispersion of Pt nanoparticles, and good electrical conductivity required for electrochemical reactions. A range of key factors are known to contribute to the performance degradation of PEMFCs that occur during long term operation and/or start-up and shutdown [12]. These mainly include dissolution/aggregation/Oswald ripening and/or poisoning of Pt catalysts. The stability of carbon support material itself is also an important issue because carbon is known to undergo electrochemical oxidation ( ) under a fuel cell operating environment, especially at potentials above 0.9 V (equation 1), leading to a loss of Pt active surface area and fuel cell performance degradation [13,14]. In literature, many methods have been reported to address these challenges, such as using carbide, nitride, or metal oxide as catalyst supports [15,16]. Recently, transitional metal silicides, such as TiSi x , have attracted tremendous interest
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Analysis  of power management in  portable embedded DSP applications

Analysis  of power management in  portable embedded DSP applications

Multimedia applications does not require a system to meet the deadline. This is acceptable as it doesnot make much difference in the output. Hua et al. [45] utilize this fact, along with the information on statistical task execution time to propose techniques to save energy in embedded systems by dynamic voltage Scaling. They have proposed two algorithms. The first algorithm ensures high completing ratio with possible lowest power consumption. The second algorithm deliberately drops some tasks to create slack for saving additional energy, so that application specific quality of service constraint is fulfilled. Thus these algorithms provide opportunity to scale between high task completion ratio and lowest possible power consumption.
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Investigation of a Pt3Sn/C Electro-Catalyst in a Direct Ethanol Fuel Cell Operating at Low Temperatures for Portable Applications

Investigation of a Pt3Sn/C Electro-Catalyst in a Direct Ethanol Fuel Cell Operating at Low Temperatures for Portable Applications

cell at low temperatures. The electro-catalytic activity of this bimetallic catalyst was compared to that of a commercial 20% Pt/C catalyst. The PtSn catalyst showed better results in the investigated temperature range (30°-70°C). Generally, Sn promotes ethanol oxidation by adsorption of OH species at considerably lower potentials compared to Pt, allowing the occurrence of a bifunctional mechanism. The bimetallic catalyst was physico-chemically characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. The presence of SnO 2 in the bulk and surface of the
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ABSTRACT: This project proposes an integrated wind and fuel power generation system fed to an ac power grid or

ABSTRACT: This project proposes an integrated wind and fuel power generation system fed to an ac power grid or

Depending on the type of fuel cell and the used fuel, the reaction mechanisms may be different from each other. We choose PEM fuel cells to consider the operation description; moreover the main concept remains the same as for the other types of fuel cells. Within the PEM fuel cells, hydrogen and oxygen are converted into water while generating electricity. A schematic diagram of the processes occurring in a PEM fuel cells is shown in Fig. 4.

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Simulation And Optimization Of Waste Gas Fuel Cell System For Power Generation

Simulation And Optimization Of Waste Gas Fuel Cell System For Power Generation

Decreasing waste gas emissions from petroleum industry is of paramount importance as they affect the environment negatively and contributes to global warming and climate changes. Industries have responded to this issue by implementing new ways to combat the flaring using conventional and innovative approaches. This research article deals with design of an integrated system comprising of solid oxide fuel cell that uses waste gases as a feedstock and generates power. The flare gases from plant units have varied composition and quality. Therefore, a thorough study was conducted to identify suitable feed stock and average composition of feedstock. Afterward, a solid oxide fuel cell was chosen as a desirable system due to high efficiency, size and feed advantages. A simulation model was developed using Aspen HYSYS simulation software. The main components of the process consists of gas treatment system, compressed and heated air and SOFC fuel cell. The fuel cell had been modeled using reactors, splitter, heater and recycle. The system generation net electricity of 20187.3 KW using 8230 Kg/hr feed. Subsequently, a heat integration was performed to optimize and reduce the heating requirement of the system. The resulting model improve model performance. Multiple case studies have been performed to gauge effect of process parameter such as composition, temperature, pressure, feed to air ratio and other parameters. It was found that mass flow rate of feed has largest impact. An overall economic evaluation of the project was performed to find the economic feasibility of the project. Monte-Carlo simulation was utilized to assess the risk of the project and profitability. Based on the result and analysis, it can be concluded that a SOFC based waste gas system can be a viable option in gas plant to minimize gas flaring and produce power.
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Development Of Portable Power Generator By Using Dynamo

Development Of Portable Power Generator By Using Dynamo

Nowadays we are living in an information technology (IT) world. Therefore at least one man has one mobile cell phone to make or accept calls, send or receive messages, play games, online shopping or act as Global Positio ni ng System (GPS) to reach a destination. All of the moment can done in few minut es with ours finger and a mobile cell phone. But, the battery storage for mobile cell phone is not enough as we need use it for few days without charging with plug, so a mobile power storage is needed when cell phone battery is not enough and this mobile power storage is called power bank. In market, there has many types and many brands of power bank. For example, solar power bank and power bank are the most popular in market. Both of them have pro and con. The table 1.1 show the comparison of power bank and the solar power bank.
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Integrated Modeling and Variable Universe Fuzzy Control of a Hydrogen-Air Fuel Cell System

Integrated Modeling and Variable Universe Fuzzy Control of a Hydrogen-Air Fuel Cell System

As Fig. 1 shown, our PEM fuel cell system, which has been designed and manufactured by the Institute of Automation of the Chinese Academy of Sciences (CASIA) and its industrial cooperator, is a 1KW electricity generation system. It uses hydrogen as fuel to take a chemical reaction with air. At the same time, byproduct water and heat have been produced. The stack of the fuel cell system has 24 cells in series and the active area of each cell is 160cm 2 . Output power of the stack is regulated by an air mass flow meter in the cathode inlet and a hydrogen mass flow meter in the anode inlet. The air mass flow meter is a kind of valve with 0 5  V input voltage and 0 100SLM  flow range, and the hydrogen mass flow meter is with 0 5  V input voltage and 0 20SLM  flow range. At the exit of the cathode and the anode channel, two hand valves whose opening are kept fixed in each experiment are equipped. The open voltage of the stack can come to 24V . However, our standard electric source of DC load is 12 V . A DC/DC buck converter is used to convert the stack voltage to standard 12 V .
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A Development Of A Portable Pneumatic Jacking System

A Development Of A Portable Pneumatic Jacking System

It can be seen that the usage of jacks is among a practical tool since jacks can be found at any hardware shops and offer variety of prices. Jacks in market ranges from small ones to bigger ones as this applies for many applications. Jacks can be sorted out into several groups such mechanical jacks, hydraulic jacks, air to hydraulic jacks and air lifting bags.

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Development Of Portable Power Generation System With Low Cost Vertical Axis Wind Turbine

Development Of Portable Power Generation System With Low Cost Vertical Axis Wind Turbine

Normally to create wind turbine such as horizontal axis wind turbine (HAWT) and vertical axis wind turbine (VAWT) is need a high cost and hard to maintenance. There are permanent and hard to change from one location to another location. HAWT need a large area to install, but VAWT are great for placement at residential location and more small scale. So, to overcome this problem, this project to develop a VAWT with a portable, an expensive, and easy to assemble wind turbine system has been introduced and discussed. This project was constructed using mostly simple tools.
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