scholarly journals Modeling Analysis of Different Renewable Fuels in an Anode Supported SOFC

2011 ◽  
Vol 8 (3) ◽  
Author(s):  
Martin Andersson ◽  
Hedvig Paradis ◽  
Jinliang Yuan ◽  
Bengt Sundén
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Molar Fraction ◽  
Reaction Rates ◽  
High Energy ◽  
Solid Oxide ◽  
Inlet Temperature ◽  
Renewable Fuels ◽  
Oxide Fuel

It is expected that fuel cells will play a significant role in a future sustainable energy system due to their high energy efficiency and possibility to use as renewable fuels. Fuels, such as biogas, can be produced locally close to the customers. The improvement for fuel cells during the past years has been fast, but the technology is still in the early phases of development; however, the potential is enormous. A computational fluid dynamics (CFD) approach (COMSOL MULTIPHYSICS) is employed to investigate effects of different fuels such as biogas, prereformed methanol, ethanol, and natural gas. The effects of fuel inlet composition and temperature are studied in terms of temperature distribution, molar fraction distribution, and reforming reaction rates within a singe cell for an intermediate temperature solid oxide fuel cell. The developed model is based on the governing equations of heat, mass, and momentum transport, which are solved together with global reforming reaction kinetics. The result shows that the heat generation within the cell depends mainly on the initial fuel composition and the inlet temperature. This means that the choice of internal or external reforming has a significant effect on the operating performance. The anode structure and catalytic characteristic have a major impact on the reforming reaction rates and also on the cell performance. It is concluded that biogas, methanol, and ethanol are suitable fuels in a solid oxide fuel cell system, while more complex fuels need to be externally reformed.

Surge Prevention Techniques for a Turbocharged Solid Oxide Fuel Cell Hybrid System

2021 ◽  
Author(s):  
L. Mantelli ◽  
M. L. Ferrari ◽  
A. Traverso
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Rotational Speed ◽  
Pressure Ratio ◽  
High Energy ◽  
Cell System ◽  
Solid Oxide ◽  
Pollutant Emissions ◽  
Inlet Temperature ◽  
Oxide Fuel

Abstract Pressurized solid oxide fuel cell (SOFC) systems are one of the most promising technologies to achieve high energy conversion efficiencies and reduce pollutant emissions. The most common solution for pressurization is the integration with a micro gas turbine, a device capable of exploiting the residual energy of the exhaust gas to compress the fuel cell air intake and, at the same time, generating additional electrical power. The focus of this study is on an alternative layout, based on an automotive turbocharger, which has been more recently considered by the research community to improve cost effectiveness at small size (< 100 kW), despite reducing slightly the top achievable performance. Such turbocharged SOFC system poses two main challenges. On one side, the absence of an electrical generator does not allow the direct control of the rotational speed, which is determined by the power balance between turbine and compressor. On the other side, the presence of a large volume between compressor and turbine, due to the fuel cell stack, alters the dynamic behavior of the turbocharger during transients, increasing the risk of compressor surge. The pressure oscillations associated with such event are particularly detrimental for the system, because they could easily damage the materials of the fuel cells. The aim of this paper is to investigate different techniques to drive the operative point of the compressor far from the surge condition when needed, reducing the risks related to transients and increasing its reliability. By means of a system dynamic model, developed using the TRANSEO simulation tool by TPG, the effect of different anti-surge solutions is simulated: (i) intake air conditioning, (ii) water spray at compressor inlet, (iii) air bleed and recirculation, and (iv) installation of an ejector at the compressor intake. The pressurized fuel cell system is simulated with two different control strategies, i.e. constant fuel mass flow and constant turbine inlet temperature. Different solutions are evaluated based on surge margin behavior, both in the short and long terms, but also monitoring other relevant physical quantities of the system, such as compressor pressure ratio and turbocharger rotational speed.

scholarly journals Integrated Cr and S poisoning of a La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) cathode for solid oxide fuel cells

RSC Advances ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 7-14
Author(s):  
Cheng Cheng Wang ◽  
Mortaza Gholizadeh ◽  
Bingxue Hou ◽  
Xincan Fan
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Cell Performance ◽  
Oxide Fuel ◽  
Performance Deterioration

Strontium segregation in a La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) electrode reacts with Cr and S in a solid oxide fuel cell (SOFC), which can cause cell performance deterioration.

scholarly journals A robust and active hybrid catalyst for facile oxygen reduction in solid oxide fuel cells

2017 ◽  
Vol 10 (4) ◽  
pp. 964-971 ◽  
Author(s):  
Yu Chen ◽  
Yan Chen ◽  
Dong Ding ◽  
Yong Ding ◽  
YongMan Choi ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide Fuel Cell ◽  
Oxygen Reduction ◽  
Electrocatalytic Activity ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Hybrid Catalyst ◽  
Fuel Cell Cathode

A hybrid catalyst coating dramatically enhances the electrocatalytic activity and durability of a solid oxide fuel cell cathode.

scholarly journals Thermoeconomic Optimization of a Hybrid Photovoltaic-Solid Oxide Fuel Cell System for Decentralized Application

2019 ◽  
Vol 9 (24) ◽  
pp. 5450
Author(s):  
Alexandros Arsalis ◽  
George E. Georghiou
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Cell System ◽  
Solid Oxide ◽  
Small Scale ◽  
Inlet Temperature ◽  
Oxide Fuel ◽  
Optimization Strategy ◽  
Commercial Building ◽  
Autonomous Operation

A small-scale, decentralized hybrid system is proposed for autonomous operation in a commercial building (small hotel). The study attempts to provide a potential solution, which will be attractive both in terms of efficiency and economics. The proposed configuration consists of the photovoltaic (PV) and solid oxide fuel cell (SOFC) subsystems. The fuel cell subsystem is fueled with natural gas. The SOFC stack model is validated using literature data. A thermoeconomic optimization strategy, based on a genetic algorithm approach, is applied to the developed model to minimize the system lifecycle cost (LCC). Four decision variables are identified and chosen for the thermoeconomic optimization: temperature at anode inlet, temperature at cathode inlet, temperature at combustor exit, and steam-to-carbon ratio. The total capacity at design conditions is 70 and 137.5 kWe, for the PV and SOFC subsystems, respectively. After the application of the optimization process, the LCC is reduced from 1,203,266 to 1,049,984 USD. This improvement is due to the reduction of fuel consumed by the system, which also results in an increase of the average net electrical efficiency from 29.2 to 35.4%. The thermoeconomic optimization of the system increases its future viability and energy market penetration potential.

Performance Comparison of Internal Reforming Against External Reforming in a Solid Oxide Fuel Cell, Gas Turbine Hybrid System

2005 ◽  
Vol 127 (1) ◽  
pp. 86-90 ◽  
Author(s):  
Eric A. Liese ◽  
Randall S. Gemmen
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Hybrid System ◽  
Waste Heat ◽  
Performance Comparison ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Internal Reforming ◽  
Hybrid Configuration

Solid Oxide Fuel Cell (SOFC) developers are presently considering both internal and external reforming fuel cell designs. Generally, the endothermic reforming reaction and excess air through the cathode provide the cooling needed to remove waste heat from the fuel cell. Current information suggests that external reforming fuel cells will require a flow rate twice the amount necessary for internal reforming fuel cells. The increased airflow could negatively impact system performance. This paper compares the performance among various external reforming hybrid configurations and an internal reforming hybrid configuration. A system configuration that uses the reformer to cool a cathode recycle stream is introduced, and a system that uses interstage external reforming is proposed. Results show that the thermodynamic performance of these proposed concepts are an improvement over a base-concept external approach, and can be better than an internal reforming hybrid system, depending on the fuel cell cooling requirements.

System Configuration and Performance Studies of Solid Oxide Fuel Cell -Gas Turbine Hybrid Cycle

2007 ◽  
Author(s):  
Wei Jiang ◽  
Ruxian Fang ◽  
Jamil A. Khan ◽  
Roger A. Dougal
Keyword(s):  
Fuel Cell ◽  
Power Plant ◽  
Solid Oxide Fuel Cell ◽  
Gas Turbine ◽  
Finite Volume ◽  
Hybrid System ◽  
High Energy ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Hybrid Cycle

Fuel Cell is widely regarded as a potential alternative in the electric utility due to its distinct advantages of high energy conversion efficiency, low environmental impact and flexible uses of fuel types. In this paper we demonstrate the enhancement of thermal efficiency and power density of the power plant system by incorporating a hybrid cycle of Solid Oxide Fuel Cell (SOFC) and gas turbine with appropriate configurations. In this paper, a hybrid system composed of SOFC, gas turbine, compressor and high temperature heat exchanger is developed and simulated in the Virtual Test Bed (VTB) computational environment. The one-dimensional tubular SOFC model is based on the electrochemical and thermal modeling, accounting for the voltage losses and temperature dynamics. The single cell is discretized using a finite volume method where all the governing equations are solved for each finite volume. Simulation results show that the SOFC-GT hybrid system could achieve a 70% total electrical efficiency (LHV) and an electrical power output of 853KW, around 30% of which is produced by the power turbine. Two conventional power plant systems, i.e. gas turbine recuperative cycle and pure Fuel Cell power cycle, are also simulated for the performance comparison to validate the improved performance of Fuel Cell/Gas Turbine hybrid system. Finally, the dynamic behavior of the hybrid system is presented and analyzed based on the system simulation.

Cogeneration of ethylene and electricity in symmetrical protonic solid oxide fuel cells based on a La0.6Sr0.4Fe0.8Nb0.1Cu0.1O3−δ electrode

2020 ◽  
Vol 8 (48) ◽  
pp. 25978-25985
Author(s):  
Jun Li ◽  
Jie Hou ◽  
Xiuan Xi ◽  
Ying Lu ◽  
Mingming Li ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Cell Reactor

Symmetrical solid oxide fuel cell reactor with BaZr0.1Ce0.7Y0.1Yb0.1O3−δ as electrolyte and La0.6Sr0.4Fe0.8Nb0.1Cu0.1O3−δ as electrodes is applied to cogenerate ethylene and electricity.

Thermodynamic Performance of a Gas Turbine Plant Combined With a Solid Oxide Fuel Cell

2008 ◽  
Author(s):  
Yousef Haseli ◽  
Ibrahim Dincer ◽  
Greg F. Naterer
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Gas Turbine ◽  
Compression Ratio ◽  
Solid Oxide ◽  
Specific Power ◽  
Inlet Temperature ◽  
Oxide Fuel ◽  
Turbine Inlet Temperature ◽  
Energy And Exergy

This paper undertakes a thermodynamic analysis of a high-temperature solid oxide fuel cell, combined with a conventional recuperative gas turbine. In the analysis the balance equations for mass, energy and exergy for the system as a whole and its components are written, and both energy and exergy efficiencies are studied for comparison purposes. These results are also verified with data available in the literature for typical operating conditions, the predictive model of the system is validated. The energy efficiency of the integrated cycle is obtained to be as high as 60.55% at the optimum compression ratio. These model findings indicate the influence of different parameters on the performance of the cycle and irreversibilities therein, with respect to the exergy destruction rate and/or entropy generation rate. The results show that a higher ambient temperature would lead to lower energy and exergy efficiencies, and lower net specific power. Furthermore, the results indicate that increasing the turbine inlet temperature results in decreasing both the energy and exergy efficiencies of the cycle, whereas it improves the total specific power output. However, an increase in either the turbine inlet temperature or compression ratio leads to a higher rate of irreversibility within the plant. It is shown that the combustor and SOFC contribute predominantly to the total irreversibility of the system; about 60 percent of which takes place in these components at a typical operating condition, with 31.4% for the combustor and 27.9% for the SOFC.

scholarly journals Structure and properties of MgMxCr2−xO4 (M = Li, Mg, Ti, Fe, Cu, Ga) spinels for electrode supports in solid oxide fuel cells

2014 ◽  
Vol 2 (42) ◽  
pp. 18106-18114 ◽  
Author(s):  
Elena Stefan ◽  
Paul A. Connor ◽  
Abul K. Azad ◽  
John T. S. Irvine
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Structure And Properties ◽  
Scaffold Materials

The paper investigates the structure and properties of novel electrode scaffold materials for solid oxide fuel cell (SOFC), such as MgMxCr2−xO4, (M = Li, Mg, Ti, Fe, Cu, Ga).

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