Direct Conversion Of Chemical Energy Research Articles

Energy and exergy analysis of an ideal molten carbonate fuel cell (MCFC) and reheat & regenerative braysson cycle hybrid system

Direct energy conversion devices are gaining prominence because of their high efficiency, as the process involves the direct conversion of chemical energy to its electrical counterpart, bypassing the thermal energy phase. Fuel cells work on the principle of a chemical reaction between fuels like Hydrogen, Methane, propane, ammonia, and an oxidizer. The working temperature of the fuel cell is as high as (600 °C–700 °C). Generally, waste heat liberated from the fuel cells was used to generate power by running the Brayton (or) Rankine cycle. This work involves exergy and energy analysis on a hybrid system made of a Molten Carbonate Fuel Cell and reheat & regenerative Braysson cycle. Combining a molten carbonate fuel cell (MCFC) with a Braysson cycle results in a novel hybrid system that offers exciting possibilities for power generation. In the analysis, Molten Carbonate Fuel Cell is assumed to operate at 650 °C, and the turbine inlet temperature (TIT) range of the Braysson cycle is taken as 400 to 600 °C. It has been noticed that different optimum pressure ratio values exist to obtain maximum output of power and maximum efficiencies. Both the exergy and energy efficiencies of the combined cycle increase with the increase in turbine inlet temperature. This combined system depicts maximum energy and exergy efficiency of 96.84% and 95.13%, respectively. Destruction rates of exergy for individual equipment and the total system are also obtained as a function of TIT and pressure ratio. The exergy destruction rates are found to be maximum in the fuel cells. An optimum pressure ratio is found to be 1.4, where fuel consumption is the least and efficiencies are the maximum.

USE OF POROUS LAYERS OF GALLIUM ARSENIDE AS ATOMIC HYDROGEN SENSORS

The modern development of nanotechnologies, gadgets, and robotics is closely related to the use of nanosized particles of metals, dielectrics, and semiconductors. Composite heterosystems based on semiconductors are used in the creation of advanced opto- and nanoelectronic devices. The operation of such devices is based on the phenomena of excitation of the electronic subsystem of the conductor. The paper investigates the occurrence of non-equilibrium chemiconductivity in gallium arsenide (GaAs) samples when the sample surface is in contact with atomic hydrogen. The effect occurs due to the non-thermal generation of electron-hole (e–h) pairs in the semiconductor wafer, thanks to the energy released during the chemical interaction of hydrogen atoms with the GaAs surface (adsorption and recombination of atoms with the formation of H2 molecules). The kinetics of chemiconductivity was studied, as well as the dependence of chemiconductivity on the density of the flow of atoms per sample and temperature. It was found that the process of generation of (e–h) pairs involves both acts of adsorption of atoms and acts of recombination of atoms into a molecule. The revealed effect of the appearance of non-equilibrium conductivity in samples of single-crystal gallium arsenide during recombination on the surface of atomic hydrogen clearly indicates the presence of effective channels for the accommodation of chemical energy by the conductor when a chemical reaction occurs on its surface. To increase the sensitivity of such a sensor by increasing the area of the "active" surface, it is proposed to use a porous layer of GaAs (por-GaAs). The phenomenon of non-equilibrium chemiconductivity in porous gallium arsenide, discovered and investigated for the first time in this paper, opens up wide prospects for the use of this semiconductor for the direct conversion of chemical energy into electrical energy. Semiconductors with a narrow bandgap of this type have prospects in the development of devices for the direct conversion of chemical energy into electrical energy, as well as in the creation of chemical sensors. The possibility of using this material as a detector of hydrogen atoms in the gas phase is substantiated.

Numerical investigation of the influence of different cooling flow channels on the thermal and water saturation distribution in a real dimensional polymer electrolyte membrane fuel cell

A fuel cell is one of the expert-presented solutions which has been developed due to the use of clean energies and direct conversion of chemical energy into electricity. Thermal and water management of the fuel cells are among the major issues which can significantly improve the performance of the fuel cell. In this study, a polymer electrolyte membrane fuel cell (PEMFC) with cooling channels was simulated in real dimensions considering most of the reactions and equations in all the sections of the fuel cell at a constant electrical current density at the cathode terminal surface. Six different cooling fields were assessed and the results were presented in the form of average temperature, maximum temperature, the mass ratio of various species, current density, index of uniformity temperature, heat transfer, and electrical voltage at the different surfaces. The accuracy of the simulation was assessed by comparing the modeled values with the experimental results and average temperature and maximum temperature were presented for various current densities. Based on the results, the four-section serpentine geometry was the best cooling channel geometry in terms of temperature; while serpentine-in-the-beginning was the best cooling channel geometry in terms of output power, absorbed heat, and water accumulation. The lowest electrical voltage at the cathode terminal was for parallel geometry (0.64 V) while its highest level (0.68 V) was in three geometries of serpentine-in-the-beginning, serpentine-at-the-end, and horizontal serpentine, showing a 6.3% improvement in the output voltage of the fuel cell.

Improved Durability of High-Performance Intermediate-Temperature Solid Oxide Fuel Cells with a Ba-Doped La0.6Sr0.4Co0.2Fe0.8O3-δ Cathode.

As a device for direct conversion of chemical energy into electrical energy, the solid oxide fuel cell (SOFC) contributes positively to the sustainable development strategy. However, the commercialization of fuel cells is still impeded by severe cathode degradation caused by its limited stability at operating temperatures and being prone to Cr-poisoning from Cr-containing alloy interconnectors commonly used in these cells. This paper reports the development of a high-durability Ba-doped LSCF(La0.6Sr0.4Co0.2Fe0.8O3-δ) cathode material under realistic fuel cell operating conditions in the presence of the Cr alloy. In particular, when tested in a symmetrical cell constructed of Ba-doped LSCF, the polarization resistance of the cell remains very low at 0.06 Ω cm2 after being tested at 800 °C for 120 h exposed to Cr in 3% humidified air. In contrast, for the undoped LSCF under the same testing conditions, the polarization resistance of the cell increases ∼10 times from 0.22 Ω cm2 of the pristine cell to 2.18 Ω cm2 after Cr-exposure testing. Furthermore, when tested in an anode-supported complete cell as a cathode under typical SOFC operation conditions at 750 °C, the cell with the Ba-doped LSCF cathode displays significantly low degradation rates of 0.00056% h-1 (without Cr) and 0.00310% h-1 (with Cr); both are much lower than that of the cell using the undoped LSCF cathode (0.00124% h-1 without Cr and 0.01082% h-1 with Cr). This enhanced durability and Cr-tolerance exhibited by the Ba-doped LSCF cathode stem from its higher crystal structure stability and improved chemical resistance compared to undoped LSCF.

Novel Trends in Proton Exchange Membrane Fuel Cells

Fuel cells (FCs) have received huge attention for development from lab and pilot scales to full commercial scale. This is mainly due to their inherent advantage of direct conversion of chemical energy to electrical energy as a high-quality energy supply and, hence, higher conversion efficiency. Additionally, FCs have been produced at a wide range of capacities with high flexibility due to modularity characteristics. Using the right materials and efficient manufacturing processes is directly proportional to the total production cost. This work explored the different components of proton exchange membrane fuel cells (PEMFCs) and their manufacturing processes. The challenges associated with these manufacturing processes were critically analyzed, and possible mitigation strategies were proposed. The PEMFC is a relatively new and developing technology so there is a need for a thorough analysis to comprehend the current state of fuel cell operational characteristics and discover new areas for development. It is hoped that the view discussed in this paper will be a means for improved fuel cell development.

Synergistic effects between solid potato waste and waste activated sludge for waste-to-power conversion in microbial fuel cells

Environmental pollution and energy shortage are two important concerns that may seriously impair the sustainable development of our society. Microbial fuel cells (MFCs) are attractive technology for the direct conversion of chemical energy of organic wastes into electric power to realize simultaneous electrical power recovery and environmental remediation. In comparison to organic wastewater, solid organic waste is more difficult to be degraded. Food waste as one of the important organic wastes has significant impact on our ecosystem. Here, by taking solid potato waste (SPW) as a typical solid food waste, the impact of waste activated sludge (WAS) as a second waste to introduce synergistic effects between them to enhance waste-to-power conversion in microbial fuel cell (MFC) was systematically investigated. For the MFCs with seven different mixing ratios of SPW and WAS, the MFC with mixing ratio of 6:1 produced the highest maximum current density and maximum power density of 320.1 mA/m2 and 14.1 mW/m2. Mixing larger ratios of WAS (2:1 and 4:1) resulted in only a very slight increase in coulombic efficiency; while mixing smaller ratios of WAS (6:1, 8:1 and 10:1) significantly increased the coulombic efficiency, and the coulombic efficiency showed an obvious increase as the WAS mixing ratio decreased. Less humic acid- and fulvic acid-like substances were formed from the hydrolysis and degradation of SPW and WAS, and most of dissolved macromolecular organic matters were hydrolyzed into organic fractions with small molecular weight. Principal component analysis indicated that the composition of dissolved organic matters was significantly influenced by different mixing ratios of SPW and WAS throughout the operation. The study provides a promising strategy for enhancing energy recovery from SPW in MFCs.

Optimal parameters estimation of the PEMFC using a balanced version of Water Strider Algorithm

Recently, much attention was paid to the application of renewable energy in environmental issues. Meanwhile, the fuel cell industry, which is considered an environmentally friendly industry, is one of the important components of this project. They are in fact devices for the direct conversion of chemical energy into electrical energy by an electrochemical reaction without the need for any mechanical parts. In this study, it is attempted to model one of their important types, called proton exchange membrane fuel cells, so that it can be used in predicting the behavior of the fuel cell and examining various parameters affecting the performance of the cell. The main idea is to optimal parameters estimation for the proton exchange membrane fuel cells by minimizing the total Squared Error value between the empirical output voltage and the approximated output voltage. For giving better results in terms of accuracy and reliability, a new design of a metaheuristic called the balanced Water Strider Algorithm is utilized. The results of the suggested method are finally validated by comparison with several latest optimizers applied on a practical test case. After running all of the optimizers 30 times independently, the proposed method with minimum absolute error equals 3.4831e−4 shows the best results toward the others.

Cataluminescence in Er-Substituted Perovskites.

Thermophotovoltaic devices have promising applications for energy conversion. However, current conversion efficiency of chemical energy to light is very low, limited by the competing process of heat dissipation released as black body radiation. From a fundamental point of view, the direct conversion of chemical energy into light without this detour is possible. This so called cataluminescence from methanol combustion over Er‐substituted SrTiO3 with high efficiency is demonstrated. The catalytically active quaternary perovskites Er0.15La0.15Sr0.55Ti0.95Cu0.05O3 − δ exsolute and reabsorb metallic Cu particles onto the surface in reducing and oxidizing conditions, respectively. Thus, it is able to manipulate the surface structure and investigate its influence on the catalytic as well as luminescent properties. The fuel to air ratio around the stoichiometry point changes the conditions from reducing to oxidizing and thereby alters the surface properties. This is evidenced by post mortem X‐ray diffraction and X‐ray photoemission as well as operando optical spectroscopy. Cataluminescence takes place under oxidizing conditions (lean fuel to air mixture) on the Er‐perovskite oxide with a strong selective near infrared emission, while reducing conditions stimulate formation of plasmonic Cu‐nanoparticles, which emit black body radiation.

Electrochemical Circuits for Autonomous Microfluidic Solution Processing

Electrochemical Circuits for Autonomous Microfluidic Solution Processing

Recent developments in electricity generation by Microbial Fuel Cell using different substrates

The rise in electrical energy demand and environmental concern results in shifting the world’s focus towards sustainable energy sources. Over-reliance of conventional fossil fuel-based power generation can be combatted using new and potential technologies like Microbial Fuel cells (MFCs). Direct conversion of chemical energy to electrical energy by the application of the naturally found microorganisms, makes MFC more convenient source of energy generation. Despite having low power density, it has been able to grab the researcher’s attention due to the flexibility of usage of various organic substrates. This review discusses the various households and industrial waste substrate which has further potential to generate power. The various liquid and solid substrates have been analysed and summarized. The substrate used, power densities, reactor volumes and specific important features used by the researchers for the improved performance have been tabulated. In a higher number of researches, liquid substrates have been comparatively more used than that of the solid substrates. Ease of handling, storage and accessibility of the liquid waste could be one of the few reasons for it. Also, in this review, various components, and key factors for the experimental design of MFC has been discussed. Along with that losses associated with MFCs and its application is explored.

Resuscitating the Mercury Beating Heart: An Improvement on the Classic Demo

The mercury beating heart is a dramatic demonstration of redox chemistry that allows for the direct conversion of chemical energy to mechanical energy without involving a machine to accomplish the transfer. Unfortunately, instructors often avoid this demonstration due to difficulties initiating the oscillating redox reaction that drives the process. Here, we describe a new method for initiating the mercury beating heart demonstration that significantly reduces the setup time and makes it easier to sustain the “beating heart” oscillations.

Microfluidic Devices Using Electrochemical Micropumps and Microvalves for Autonomous Solution Processing

In realizing sophisticated micro analytical devices, controlled solution transport in microfluidic channels is indispensable. The procedures have predominantly been conducted using external pumps (or pressure source) and valves. However, because of this, the entire setups become very bulky, although the chips may be small. If the control of solution transport is realized using integrated microfluidic components, it will accelerate automation and realization of user-friendly devices. Apart from chemical analysis, realization of artificial lives that move by direct conversion of chemical energy to mechanical energy is becoming a hot topic. Independent autonomous microfluidic systems that can control chemical reactions in a coordinated manner can also be critical components in these devices. In this study, we attempted to realize such autonomous microfluidic devices by integrating simple switchable hydrophobic microvalves that employ a conducting polymer and pressure changes by electrochemical production and shrinkage of hydrogen bubbles.Doped polypyrrole (PPy) was used for the valve. A platinum electrode was formed on a glass substrate, and PPy was grown on the electrode. For this purpose, the electrode was immersed in a solution containing 0.2 M pyrrole and 0.2 M sodium dodecylbenzenesulfonate (NaDBS), and electropolymerization was carried out at a constant current of 10 μA. In as-deposited PPy, the alkyl chains of NaDBS stand upward and the surface is hydrophobic. When PPy is reduced, polar groups come to the surface and becomes hydrophilic.First, a two-channel test device with a control flow channel and a main flow channel was fabricated (Figure 1). The valve was formed in the main flow channel and a zinc electrode was formed in the control flow channel. The electrodes were connected each other. Also, solutions in the solution reservoirs of the two flow channels were connected with an iridium wire with oxides on both ends as an alternative for a liquid junction. When a solution was injected into the main flow channel, it stopped at the valve. When another solution was injected into the control channel and wetted the zinc electrode, PPy on the valve was reduced. As a result, and the valve opened.As the next step, a three-channel device was fabricated (Figure 2). Interdigitated platinum electrodes were formed in flow channel 2 in the figure. One of them was connected to a zinc electrode in flow channel 1 and the other was connected to a platinum electrode in flow channel 3. Solutions in the reservoirs of the flow channels were connected with Ag/AgCl wires. As a preliminary experiment, a pH indicator (thymol blue) was first injected into flow channel 2. When a KCl solution was injected into flow channel 1, the color of the area around the interdigitated electrodes of flow channel 2 changed to blue by the electrolysis of water. When a 0.1 M AgNO3 solution was injected into flow channel 3, the color changed to yellow again because of the oxidization of hydrogen bubbles.Another device with the same basic structure was used to demonstrate autonomous bidirectional transport of a solution (Figure 3). In addition to the structures shown in Figure 2, the PPy valve used in the device shown in Figure 1 was formed in flow channel 3 to control the injection of the solution in the reservoir. The valve was connected to a zinc electrode formed at the end of flow channel 2. Furthermore, solution reservoirs were closed with a polyimide tape. Following the same procedure for the previous device, hydrogen bubbles were produced on one of the interdigitate electrodes in flow channel 2 by the reduction of protons. When the solution in flow channel 2 reached the zinc electrode at the end, the valve in flow channel 3 opened and a AgNO3 solution flowed through the platinum electrode. Following this, Ag+ ions were reduced to silver there and the hydrogen bubbles in flow channel 2 were oxidized on one of the interdigitate electrodes. As a result, the bubbles shrank and the solution in the flow channel moved backward.For the device shown in Figure 3, the injection of the solution in flow channel 1 can be carried out by forming an additional valve at the solution reservoir and open it using another zinc electrode in another control flow channel. Many units like the one shown in Figure 3 can be connected to the same control flow channel and operated sequentially. The technique will enable autonomous multiplexed and/or sequential processing of solutions within microfabricated analytical devices and autonomous actuation of soft robots. Figure 1

Waste to Energy Conversion and Sustainable Recovery of Nutrients from Pee Power - Recent Advancements in Urine-Fed MFCs

Microbial Fuel Cells (MFCs) offer a sustainable solution for alternative energy production by employing microorganisms as catalysts for direct conversion of chemical energy of feedstock into electricity. Electricity from urine (urine-tricity) using MFCs is a promising cost-effective technology capable of serving multipurpose benefits - generation of electricity, waste alleviation, resource recovery and disinfection. As an abundant waste product from human and animal origin with high nutritional values, urine is considered to be a potential source for extraction of alternative energy in the coming days. However, developments to improve power generation from urine-fed MFCs at reasonable scales still face many challenges such as non-availability of sustainable materials, cathodic limitations, and low power density. The aim of this paper was to critically evaluate the state-of-the-art research and developments in urine-fed MFCs over the past decade (2008-2018) in terms of their construction (material selection and configuration), modes of operation (batch, continuous, cascade, etc.) and performance (power generation, nutrient recovery and waste treatment). This review identifies the preference for sources of urine for MFC application from human beings, cows and elephants. Among these, human urine-fed MFCs offer a variety of applications to practice in the real-world scenario. One key observation is that, effective disinfection can be achieved by optimizing the operating conditions and MFC configurations without compromising on performance. In essence, this review demarcates the scope of enhancing the reuse potential of urine for renewable energy generation and simultaneously achieving resource recovery.

Superprotonics: New Materials for Energy-Efficient Technologies

One of the most rapidly developing directions in the field of alternative energy sources is hydrogen energetics. Fuel cells, the main component of which is a proton-exchange membrane, facilitate the direct conversion of chemical energy into electrical energy. Superprotonic crystals are promising materials for the creation of proton-exchange membranes of fuel cells and other electrochemical. Multicomponent water–salt growth systems are studied in order to obtain new superprotonic crystals MmHn(AO4)(m + n)/2 ⋅ yH2O (M = K, Rb, Cs, NH4, AO4 = SO4, SeO4, HPO4) and modify the properties of known compounds. The conditions for the growth of a number of new superprotonics are found, and the relationships between their structure and properties are studied.

Розвиток світового ринку енергоустановок на паливних елементах. СтРозвиток світового ринку енергоустановок на паливних елементах. Створення нормативної бази водневої енергетикиворення нормативної бази водневої енергетики

We show the importance of development and implementation of new hydrogen power systems for different branches of the Ukrainian economy. It is determined that the key technologies for the creation of hydrogen power in Ukraine are the technologies of hydrogen production using own energy sources and the direct conversion of chemical energy of hydrogen fuels into electricity in fuel cells. We present the main characteristics and advantages of fuel cell power plants (FCPP) and the global volume of their application for different industries. The total electric capacity of FCPP working in 2019 became more than 11 times greater as compared with 2009 and reached 1,100 MW. It was established that the introduction of fuel cell technologies in industrialized countries is considered as a basis for the creation of a centralized world hydrogen economy with the presence and further development of extensive hydrogen infrastructure. The state of work on standardization in the field of hydrogen power at the international level is analyzed, and the complexity and multiplicity of such tasks are shown. It is substantiated that the appropriate base of normative documents is necessary for the practical implementation of energy-efficient and environmentally friendly hydrogen technologies in Ukraine, in particular, for the production or import of equipment with its subsequent certification. These normative documents should be harmonized with European and international ones in order to remove possible technical barriers in trade.

Molybdate pumping into the molybdenum storage protein via an ATP-powered piercing mechanism

The molybdenum storage protein (MoSto) deposits large amounts of molybdenum as polyoxomolybdate clusters in a heterohexameric (αβ)3 cage-like protein complex under ATP consumption. Here, we suggest a unique mechanism for the ATP-powered molybdate pumping process based on X-ray crystallography, cryoelectron microscopy, hydrogen-deuterium exchange mass spectrometry, and mutational studies of MoSto from Azotobacter vinelandii. First, we show that molybdate, ATP, and Mg2+ consecutively bind into the open ATP-binding groove of the β-subunit, which thereafter becomes tightly locked by fixing the previously disordered N-terminal arm of the α-subunit over the β-ATP. Next, we propose a nucleophilic attack of molybdate onto the γ-phosphate of β-ATP, analogous to the similar reaction of the structurally related UMP kinase. The formed instable phosphoric-molybdic anhydride becomes immediately hydrolyzed and, according to the current data, the released and accelerated molybdate is pressed through the cage wall, presumably by turning aside the Metβ149 side chain. A structural comparison between MoSto and UMP kinase provides valuable insight into how an enzyme is converted into a molecular machine during evolution. The postulated direct conversion of chemical energy into kinetic energy via an activating molybdate kinase and an exothermic pyrophosphatase reaction to overcome a proteinous barrier represents a novelty in ATP-fueled biochemistry, because normally, ATP hydrolysis initiates large-scale conformational changes to drive a distant process.

Investigación de Celdas de Combustible de Amoniaco Directo como fuente de Energía Alternativa. Desarrollo de Electrocatalizadores para las Reacciones de Electrodo en Medio Alcalino

Las reservas de combustibles fósiles se consumen en cantidades crecientes y existe actualmente una gran preocupación en los gobiernos centrales por el grado de contaminación ambiental alcanzado durante las últimas décadas a nivel mundial. Disponer de energía es una necesidad en la vida moderna y poseerla se convertirá, en los próximos años, en un bien de alto valor en las sociedades desarrolladas. Las celdas de combustible son dispositivos que permiten la conversión directa de la energía química contenida en ciertos compuestos como el hidrógeno, metanol, etanol, amoníaco, en energía eléctrica. Las celdas de combustible alcalinas (AFCs) presentan una eficiencia mucho mayor que las que operan en medio ácido. A diferencia del metanol, etanol y etilenglicol, el amoníaco es un compuesto libre de carbono, por lo que no presenta como producto de reacción CO2, esto hace a el amoníaco un combustible ideal para las celdas con cero emisiones. Muchos investigadores ya han denominado al amo níaco como el combustible del futuro. La producción de amoníaco emplea como materia prima N2 del aire e H2 mediante un proceso bien conocido, sencillo y de bajo costo, empleando esencialmente el proceso Haber-Bosch. En nuestro país, se produce un excedente de NH3 de 80.000 ton/año, que mayormente se exporta. Desde el 2005, se han incrementado significativamente las publicaciones científicas con estudios detallados de la oxidación de amoníaco en medio alcalino y recientemente se han reportado potencias picos de 72 mW cm-2utilizando una Celda de Combustible Alcalina de Amoníaco Directo (DAAFC). Esta propuesta de tesis pretende realizar aportes significativos en el área de energías alternativas y específicamente en el desarrollo de las DAAFCs. Se plantea como objetivo general desarrollar celdas alcalinas de amoniaco directo como una fuente de energía alternativa que trabaje a baja temperatura empleando membrana sólida intercambiadora de aniones. En resumen, los objetivos específicos serán: -Sintetizar y caracterizar física y electroquímicamente electrocatalizadores para la reacción de reducción de oxígeno (ORR). -Sintetizar y caracterizar física y electroquímicamente electrocatalizadores para la reacción de oxidación de amoníaco (AOR).-Desarrollar ensambles electrodo-membrana-electrodo (MEAs) con los catalizadores sintetizados en el laboratorio y evaluar física y electroquímicamente dichas MEAs. -Desarrollar un prototipo de Celda de Combustible Alcalina de Amoniaco Directo (DAAFC).

Direct Conversion of Chemical Energy into Electrical Energy in the Combustion of a Thin Three-Layer Charge

This paper presents a study of direct conversion of chemical energy into electrical energy during the combustion of a (80Zr + 20CuO)–(LiF + CaF2 + MgF2)–(15Zr + 85CuO) thin three-layer condensed energy system, which is a high-temperature galvanic cell. It is determined that this cell during combustion generates an electric signal with an amplitude of 1.6 V and a half-width of 15 s. Its formation mechanism is proposed. A time-resolving X-ray diffraction method is used to identify the phases formed.

Direct Ammonia-Fueled Solid Oxide Fuel Cells

Ammonia, as a hydrogen carrier, has a much higher volumetric energy density than hydrogen and can be safely handled and distributed in a liquid form at an ambient temperature with a pressure greater than 1MPa. Similar to hydrogen, a clean-burning ammonia potentially can be used for power generation with zero greenhouse gas emissions. A Solid Oxide Fuel Cell (SOFC), typically operating at a temperature of 700ºC – 900ºC, has been widely acknowledged by the R&D society for a direct conversion of chemical energy of fuels (e.g. hydrocarbon fuels, ammonia, etc.) into electricity at a proven efficiency as high as 60%. Lowering the SOFC operating temperature to 700°C or below potentially enables considerable cost reduction with opportunities of using inexpensive materials for constructing SOFC systems that otherwise could not be considered. However, the corresponding SOFC inevitably faces challenges of higher electrode polarization losses and electrolyte ohmic losses, as well as reduced electrode catalytic activities. Chemtronergy is actively pursuing the development of the anode-supported SOFC technology capable of operating directly on the ammonia fuel at a temperature below 650ºC for reliable power generation. This talk will cover discussions of cell materials design and ammonia catalyst consideration for the mitigation of the increased polarization losses and ammonia reaction with the nickel-based anode, respectively, caused by lowering operating temperatures. Materials implementation and validation on both button cells (2 cm2) and single cells (100 cm2) over time will also be presented.

Direct Conversion of Chemical Energy into Electric Energy in the Combustion of a Thin Three-Layer Charge

Direct Conversion of Chemical Energy into Electric Energy in the Combustion of a Thin Three-Layer Charge