Search

© 2021 Hydrogen Energy Publications LLCSolid oxide fuel cells that are designed in different geometrical structures (planar, tubular, flat-tubular, etc.) are dirt-free, quiet, and efficient cells that run using different fuels including contagions fuels. In this work, the performance of a 3D model of direct ammonia feed anode supported flat-tubular solid oxide fuel cell having six fuel supply channels was developed, investigated, and elucidated numerically in comparison with hydrogen fuels at different operating conditions using COMOSOL Multiphysics. The finding of this study is revealed that the performance of the developed model that is running with direct ammonia is better than hydrogen feed one using the same geometrical dimensions and operating parameters. It is also confirmed that direct ammonia feed anode supported flat-tubular solid oxide fuel cell has outstanding performance over the corresponding anode supported tubular solid oxide fuel cell using the same active cell surface area, gas channel length, and operating conditions. Parametric sweep analyses have been also performed on selected operating parameters and the outcomes revealed that the working temperature and the amount of reactant gases have a powerful impact on cell performance. Thus, ammonia is a green auspicious, and profitable candidate to use as a carbon-neutral fuel for anode supported flat-tubular solid oxide fuel cells in the near future.

Renewable energy will be a panacea for environmental difficulties due to the extensive usage of carbon-rich fuels as a main source of energy. As a result, hydrogen-fueled solid oxide fuel cell is a revolutionary clean technology that has a great contribution in solving the current energy and environmental-related challenges. Thus, a 3D model of hydrogen and coal gases fueled solid oxide fuel cell (H2-SOFC) using different electrolytes has been developed and simulated using COMSOL commercial software to explore the performance of electrolyte supported SOFC. The performance of the developed model has been studied and characterized using different differential equations. Accordingly, it has been found that the performance of hydrogen-fueled oxide ion conducting electrolytes (SOFC-O) is lower than that of protonic conducting one (SOFC-H) at 800 degrees C. Furthermore, a numerical simulation has been conducted to investigate the result of temperature changes on SOFC performance at 400 degrees C, 600 degrees C, and 800 degrees C for proton-conducting SOFC and 800 degrees C and 1000 degrees C for oxygen-conducting SOFC. It has been demonstrated that SOFC-O shows a better performance at high temperatures compared with SOFC-H while SOFC-H can be an agreeable selection at medium temperatures. Therefore, this study reveals that the temperature augments the performance of both electrolytes, yet at higher working temperatures SOFC-H becomes more advantageous than SOFC-O to use hydrogen and coal gas as a primary fuel. Besides, the effect of channel height was also analyzed numerically and the finding disclosed that decreasing the channel height emerges in a curtly current path. Thus, it can be reasoned out that the performance of SOFC decreases when the channel height is increased. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

The main aim of this research is to investigate the performance of ammonia-powered microtubular solid oxide fuel cells in order to use ammonia as a possible candidate for eco-friendly and sustainable power generation systems. The performance of a direct ammonia-powered cell has been elucidated and validated with the experimental results of pure hydrogen gas at Nigde Omer Halisdemir University Prof. T. Nejat Veziroglu Clean Energy Research Center. For both studies, the cathode electrode is supplied with atmospheric air. The performance of anode, electrolyte, and cathode-supported microtubular solid oxide fuel cells has been compared numerically. The findings confirmed that the peak possible power densities obtained numerically using direct ammonia, hydrogen and experimentally using pure hydrogen gas are is 628.92 mW/cm(2), 622.29 mW/cm(2)' and, 589.28 mW/cm(2) respectively at the same geometrical dimensions, component materials, and operating parameters. Thus, the results of this study demonstrate that simultaneous experimental and numerical studies make a great contribution to minimizing biases due to literature data during model validation. The numerical simulation also indicates that the performance of cathode supported is superior to that of anode supported cells run with hydrogen and ammonia fuel. Likewise, parametric sweep analysis asserts that the working temperature has a greater effect than operating pressure on tubular cell performance. Therefore, the results of this study advise that ammonia will become a carbon-free alter- native fuel for solid oxide fuel cells in the coming years. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Nowadays, the most decisive challenges we are fronting are perfectly clean energy making for equitable and sustainable modern energy access, and battling the emerging alteration of the climate. This is because, carbon-rich fuels are the fundamental supply of utilized energy for strengthening human society, and it will be sustained in the near future. In connection with this, electrochemical technologies are an emerging and domineering tool for efficiently transforming the existing scarce fossil fuels and renewable energy sources into electric power with a trivial environmental impact. Compared with conventional power generation technologies, SOFC that operate at high temperature is emerging as a frontrunner to convert the fuels chemical energy into electric power and permits the deployment of varieties of fuels with negligible ecological destructions.According to this critical review, direct ammonia is obtained as a primary possible choice and price-effective green fuel for T-SOFCs. This is because T-SOFCs have higher volumetric power density, mechanically stable, and high thermal shocking resistance. Also, there is no sealing issue problem which is the chronic issues of the planar one. As a result, the toxicity of ammonia to use as a fuel is minimized if there may be a leakage during operation. It is portable and manageable that can be work everywhere when there is energy demand. Besides, manufacturing, onboard hydrogen deposition, and transportation infrastructure connected snags of hydrogen will be solved using ammonia. Ammonia is a low-priced carbon-neutral source of energy and has more stored volumetric energy compared with hydrogen. Yet, to utilize direct NH3 as a means of hydrogen carrier and an alternative green fuel in T-SOFCs practically determining the optimum operating temperatures, reactant flow rates, electrode porosities, pressure, the position of the anode, thickness and diameters of the tube are still requiring further improvement. Therefore, mathematical modeling ought to be developed to determine these parameters before planning for experimental work. Also, a performance comparison of AS, ES, and CS- T-SOFC powered with direct NH3 will be investigated and best-performed support will be carefully chosen for practical implementation and an experimental study will be conducted for verification based on optimum parameter values obtained from numerical modeling.

The main emphasis of this work is developing a 3D numerical model and investigating the performance characteristic of a direct ammonia fuelled protonic-conducting tubular solid oxide fuel cell (NH3-T-SOFC-H) in comparison with the corresponding hydrogen-fuelled one and direct ammonia feed oxygen-ion conducting tubular solid oxide fuel cell (NH3-T-SOFC-O) under the same operating parameters and geometrical shape. The findings revealed that NH3-T-SOFC-H has outstanding performance over T-SOFC-O counterparts at intermediate temperature (973 K) when operated under similar working conditions and geometrical designs. On the other hand the NH3-T-SOFC-O is promising for higher operating temperatures. The outcomes of the study are also confirmed that the power performance of NH3-AS-T-SOFC-O is better than the other supports of both electrolytes when the anode electrode is constructed at the outside portion of the tubular cell. Yet, the other remarkable result found in this study is that NH3- CS- T-SOFC-O has outstanding performance compared to all supports of both electrolytes when the fuel electrode is built in the inner portion of the tube. In addition, the finding indicates that the power performance of ammonia-fuelled tubular cells is strongly influenced by the anode position, operating temperatures, and pressures in both electrolytes yet the effect of cell temperature is more influential in the protonic-conducting cell. It is also observed that the performance of ES-T-SOFC is lower than AS- and CS-T-SOFC in both electrolytes and anode positions. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Nowadays, carbon-rich fuels are the principal energy supply utilized for powering human society, and it will be continued for the next few decades. Connecting with this, modern energy technologies are very essential to convert the available limited carbon-rich fuels and other green alternative energies into useful energy efficiently with an insignificant environmental impression. Amongst all kinds of power generation systems, SOFCs running with high temperatures are emerging as a frontrunner in chemical to electrical transformation efficiency, allows the engagement of all-embracing fuel varieties with negligible environmental impact. This study investigates the effect of ammonia usage in tubular SOFC performance. Firstly, the use of ammonia and hydrogen in the electrolyte supported SOFC (ES-SOFC) has investigated. Then, the effect of using ammonia in anode supported SOFC (AS-SOFC), ES-SOFC and cathode-supported SOFC (CS-SOFC) on performance has been examined by using COMSOL software. As a result of the study performed, it is found that the ammonia can be used in tubular SOFC's as a carbon-free fuel and CSSOFC shows better performance compared with ES-SOFC and AS-SOFC. Besides, the findings of this study indicate that the use of ammonia as a fuel for SOFCs is comparable to the use of hydrogen. (c) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Nowadays, Carbon-rich fuels are the principal energy supply utilized for powering human society, and it will be continued for the next some decades. Connecting with this, modern energy technologies are very essential to convert the available limited carbon-rich fuels and other green alternative energies into useful energy efficiently with an insignificant environmental impression. Therefore, the main objectives of this study are assessing the potential of municipal biomass solid waste for briquette production in Bahir Dar city, Ethiopia. To conduct this research, various data collection instrument tools were used to achieve the intended objectives for instance questionnaire, direct measurement, field observation and related literature based on necessity. Moreover, to confirm the reliability of the information obtained through a questionnaire, a focus group discussion was conducted with different concerned bodies. The main finding of this study shows that Bahir Dar city has the potential to generate 50.19 tons of municipal biomass solid waste per day. The collected waste was characterized as 82.5% of them is organic waste that may be converted in to clean energy (briquette and biogas) based on their sized whereas the remaining 17.5% of them were inorganic (plastics, glass, and metals) that can be resent for recycling and reuse to their original sources. Biomass-related solid municipal waste is a promising potential to utilize as a feedstock for briquette production. Besides, it has a prodigious role to reduce deforestation, land degradation, save foreign currency and reduce greenhouse gas emissions. This is because the demands of household’s energy that was fulfilled with wood charcoals and fossil fuels are substituted with locally available renewable energy sources. The experimental results confirmed that all the physicochemical properties of briquette charcoal that are produced from municipal solid biomass waste were acceptable. Besides, the burning efficiency of the briquette, fanning time and carbon content determination were measured and obtained as adequate results based on the standards. Hence, it will be a possible alternative fuel for household energy using a special design stove that is available in the market. It has also played a great role in waste management and treatment system to achieve sustainable clean city developments.

Organic Waste is undesirable matter, which is most frequently generated by human activity that causes environmental pollution. Therefore, domestic biogas production is one of the most promising method of biomass wastes treatment because it provides a source of energy while simultaneously resolving ecological, environmental and agrochemical issues. The provision of bio‐energy tackles both energy poverty and the reliance on polluting and Non ‐ Renewable fuels as a result matured biogas production technology has led to the development of a number of biogas appliances for lighting, power generation, and cooking. The most promising among them is the biogas energy in order to meet the energy requirement for cooking application at domestic and community level. In this paper, an attempt has been made to design and develop a cylindrical torpispherical fixed dome bio digester for cooking application in the condominium houses at Debiza site in Debre Markos, East Gojjam in Amhara Region. The size of biogas plant is 53m3 and the input materials are different wastes such as kitchens, food waste and the human excreta from a total of 357 people living in four building of 120 residence. The gas production rating of the developed biogas plant is 25.36m3/day, which accounts 60.73% of the energy consumption that covers all the energy demand of firewood, charcoal and animal dung cakes that used for baking Injera and bread. The amount of gas obtained averagely, 0.211m3/ per household per day for cooking purpose.

This paper deals with the transesterification of Ricinus Communis (RC) oil with methanol to produce biodiesel in the presence of KOH as a catalyst. Moreover, this study analysis the fuel properties of RC biodiesel and diesel fuel blend to use castor oil methyl ester as a possible alternative fuel for diesel engines. Various properties of the RC biodiesel and their blends such as density, kinematic viscosity, iodine value, saponification number, Cetane number, heating value, flash point and acid value were determined. The experimental results were compared well with American Society for Testing and Materials (ASTM D6751) and European biodiesel standards (EN 14214). The experimental design as well as statistical analysis were done and analyzed using design expert 8.0.7.1 version soft ware. The predicted optimum conditions for castor oil biodiesel production were a reaction temperature of 59.890c, methanol to oil ratio of 8.10:1 and a catalyst of 1.22 wt% of oil. The methyl ester content under these optimum conditions was 94.5% w/w of oil, and all of the measured properties of the biodiesel met the international standards of EN14214 and ASTM D 6751 with the exception of density and viscosity. Therefore, the viscosity and density of the ester was high and further reduced by blending with diesel fuel up to B45 to satisfy within the ASTM D6751 and EN 14214 limits for biodiesel.