Daily Operation Optimization of a Residential Molten Carbonate Fuel Cell Power System Using Genetic Algorithm

To decrease the cost of electricity generation of a residential molten carbonate fuel cell （MCFC） power system, multi-crossover genetic algorithm （MCGA）, which is based on ＂multi-crossover＂ and ＂usefulness-based selection rule＂, is presented to minimize the daily fuel consumption of an experimental 10kW MCFC power system for residential application. Under the operating conditions obtained by MCGA, the operation constraints are satisfied and fuel consumption is minimized. Simulation and experimental results indicate that MCGA is efficient for the operation optimization of MCFC power systems.

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 cm2 and of 120 cm2. Some results obtained in our study shown significant performance indicators for PEMFC stack (composed of 2 cells and 4 cells in a series) at different humidification levels.

Power Conversion System Strategies for Fuel Cell Vehicles

Power electronics is an enabling technology for the development of environmental friendly fuel cell vehicles, and to implement the various vehicle electrical architectures to obtain the best performance. In this paper, power conversion strategies for propulsion and auxiliary power unit applications are described. The power electronics strategies for the successful development of the fuel cell vehicles are presented. The fuel cell systems for propulsion and for auxiliary power unit applications are also discussed.

Parameters Influencing Power Generation in Eco-friendly Microbial Fuel Cells

Pulp and papermaking industries generate high volumes of carbohydrate-rich effluents. Microbial fuel cell(MFC) technology is based on organic materials' consumption and efficient power production. Using a classical two-chamber lab-scale MFC design with an external resistance of2000 W, we investigated the effects of anode chamber biofilm adaptation(ACBA) and cathode chamber redox solutions(CCRS) on the operation efficiency of MFC when treating wastewater. In ACBA studies, biofilm growth activation showed an increase in the power density to 20.48, 35.18, and36.98 mW/m^2 when the acetate feeding concentrations were 3, 6, and 12 g/L,respectively. Improvement by biofilm adhesion on granular activated carbon(GAC) was examined by scanning electron microscopy(SEM). The obtained power density increased to 25.47, 33.42, and 40.39 mW/m^2 when the GAC particles concentrations were 0, 50, and 100 g/L, respectively. The generated power densities were 51.26 and 40.39 mW/m^2 as well as the obtained voltages were 0.41 and 0.72 V when the electrode area increased from 16 to 64 cm^2,respectively. Using the MFC optimized parameters, CCRS studies carried out using five different cathodic redox solutions. The results revealed that the use of manganese dioxide dissolved in hydrochloric acid generated the maximum power density of 112.6 mW/m^2, current density of 0.094 A/m^2, and voltage of1.20 V with a successful organic removal efficiency of 86.0% after 264 h of operation.

Regulation of Power Conversion in Fuel Cells

Here we report a regulation about power conversion in fuel cells. This regulation is expressed as that total power produced by fuel cells is always proportional to the square of the potential difference between the \{equilibrium\} potential and work potential. With this regulation we deduced fuel cell performance equation which can describe the potential vs.the current performance curves, namely, polarization curves of fuel cells with three power source parameters: equilibrium potential E_0; internal resistance R; and power conversion coefficient K. The concept of the power conversion coefficient is a new criterion to evaluate and compare the characteristics and capacity of different fuel cells. The calculated values obtained with this equation agree with practical performance of different types of fuel cells.

Maximum Power Point Tracking With Fractional Order High Pass Filter for Proton Exchange Membrane Fuel Cell

Proton exchange membrane fuel cell (PEMFC) is widely recognized as a potentially renewable and green energy source based on hydrogen. Maximum power point tracking (MPPT) is one of the most important working conditions to be considered. In order to improve the performance such as convergence and robustness under disturbance and uncertainty, a fractional order high pass filter (FOHPF) is applied for the MPPT controller design based on the traditional extremum seeking control (ESC). The controller is designed with integerorder integrator (IO-I) and low pass filter (IO-LPF) together with fractional order high pass filter (FOHPF), by substituting the normal HPF in the original ESC system. With this FOHPF ESC, better convergence and smoother performance are achieved while maintaining the robust specifications. First, tracking stability is discussed under the commensurate-order condition. Then, simulation results are included to validate the proposed new FOHPF ESC scheme under disturbance. Finally, comparison results between FOHPF ESC and the traditional ESC method are also provided. © 2014 Chinese Association of Automation.

Application of Solid Oxide Fuel Cell-Auxiliary Power Unit on Different Trucks in Northeast China

A diesel engine of conventional trucks has a low efficiency under the idling condition,leading to a high cost for heating or cooling in the cab during night. The solution to this problem will have great significance on energy conservation and emission reduction. A new auxiliary power unit of solid oxide fuel cell( SOFCAPU) with high efficiency solves this problem perfectly. Heat pump air conditioner is considered as a promising device for the application of SOFC-APU with a high cooling and heating efficiency. To make a quantitative analysis for the application of SOFC-APU,a model is built in Matlab / Simulink. The diesel engine model and SOFC-APU model are fitted based on some experimental data of SOFC-APU and diesel engine during the idling operation. An analysis of the application of SOFC-APU on different trucks in Northeast China is comprehensively made,including efficiency and emission.

Study on an environmental-friendly and high-efficient fuel cell energy conversion system

The kinds and the distribution of the coal in China are investigated. The results indicated that the 80% coal in China is used by the method of the coal gasification. The possibility of utilization and development of the fuel cell power plant in China is analyzed. A combined cycle generation system is designed. Its net electrical efficiency is about 55%(LHV), which is higher than that of the fire power plant. So it is environmental friendly and high efficient generation mode.

Prospects and challenges of graphene based fuel cells

Novel characteristics of graphene have captured great attention of researchers for energy technology applications.Incorporation of graphene related hybrid and composite materials have demonstrated high performance and durability for fuel cell energy conversion devices.This article overviews graphene based materials for fuel cell technology applications such as electrodes additives,bipolar plates and proton conducting electrolyte membrane.The graphene dispersion over electrodes has revealed enhanced exposure of electrochemically active surface area for improved electro-catalytic activity towards fuel oxidation and oxidant reduction reactions.The issue of device stack durability and degraded performance due to corrosion of bipolar plates is discussed by incorporating graphene based materials.In proton exchange membrane devices,graphene as an electrolyte has shown an excellent performance towards high ionic conductivity and power density.The graphene incorporation in fuel cell devices has exhibited commendable performance and has bright future for commercial applications.

Characterization of Fe/N-doped graphene as air-cathode catalyst in microbial fuel cells

This work proposed a simple and efficient approach for synthesis of durable and efficient non-precious metal oxygen reduction reaction（ORR） electro-catalysts in MFCs. The rod-like carbon nanotubes（CNTs）were formed on the Fe–N/SLG sheets after a carbonization process. The maximum power density of1210 ± 23 m W·mobtained with Fe–N/SLG catalyst in an MFC was 10.7% higher than that of Pt/C catalyst(1080 ± 20 mW ·m) under the same condition. The results of RDE test show that the ORR electron transfer number of Fe–N/SLG was 3.91 ± 0.02, which suggested that ORR catalysis proceeds through a four-electron pathway. The whole time of the synthesis of electro-catalysts is about 10 h, making the research take a solid step in the MFC expansion due to its low-cost, high efficiency and favorable electrochemical performance. Besides, we compared the electrochemical properties of catalysts using SLG, high conductivity graphene（HCG, a kind of multilayer graphene） and high activity graphene（HAG, a kind of GO） under the same conditions, providing a solution for optimal selection of cathode catalyst in MFCs.The morphology, crystalline structure, elemental composition and ORR activity of these three kinds of Fe–N/C catalysts were characterized. Their ORR activities were compared with commercial Pt/C catalyst.It demonstrates that this kind of Fe–N/SLG can be a type of promising highly efficient catalyst and could enhance ORR performance of MFCs.

Electrochemical Properties of Electrodes with Different Shapes and Diffusion Kinetic Analysis of Microbial Fuel Cells on Ocean Floor

Microbial fuel cell(MFC) on the ocean floor is a kind of novel energy-harvesting device that can be developed to drive small instruments to work continuously.The shape of electrode has a great effect on the performance of the MFC.In this paper,several shapes of electrode and cell structure were designed,and their performance in MFC were compared in pairs:Mesh(cell-1) vs.flat plate(cell-2),branch(cell-3) vs.cylinder(cell-4),and forest(cell-5) vs.disk(cell-6) FC.Our results showed that the maximum power densities were 16.50,14.20,19.30,15.00,14.64,and 9.95 mWm-2 for cell-1,2,3,4,5 and 6 respectively.And the corre-sponding diffusion-limited currents were 7.16,2.80,18.86,10.50,18.00,and 6.900 mA.The mesh and branch anodes showed higher power densities and much higher diffusion-limited currents than the flat plate and the cylinder anodes respectively due to the low diffusion hindrance with the former anodes.The forest cathode improved by 47% of the power density and by 161% of diffusion-limited current than the disk cathode due to the former's extended solid/liquid/gas three-phase boundary.These results indicated that the shape of electrode is a major parameter that determining the diffusion-limited current of an MFC,and the differences in the elec-trode shape lead to the differences in cell performance.These results would be useful for MFC structure design in practical applica-tions.

Effect of bamboo charcoal filler on the performance of microbial fuel cell

微生物燃料电池（MFC）的阳极对提高MFC产电性能有至关重要的影响.利用竹炭比表面积大、吸附能力强等特性,将其作为“三合一”膜电极MFC的阳极填充材料,通过增大阳极比表面积来提高其产电能力.实验结果表明,加入竹炭至阳极室后,MFC最高输出电压（外接电阻1 000Ω时）由0.280V增大到0.387V,提高了38.2％,并且输出电压更加稳定;而最大功率密度也由原来的0.22 W/m3增大到1.42 W/m3,同时内阻降低了80.85％（由235 Ω降为45 Ω）;库仑效率由15.0％增大到25.6％.说明MF℃阳极室填充竹炭可以显著促进MFC的产电性能.

Microbial Fuel Cell Technique for Environment Monitoring

The increasingly serious environment pollution has put forward higher and higher requirement for environment monitoring technique,and conventional environment monitoring methods could not satisfy the requirements from industrial development. Microbial fuel cells( MFCs) could be used for online BOD monitoring,toxicity detection,microbial activity detection and microbial quantity detection,and as power sources for environment monitoring sensors. The technique has the advantages of simple and rapid operation,high sensitivity and good reproducibility,and serve is capable of performing online in-situ monitoring. It is the newest environment monitoring technique,with a broad application prospect. In this paper,the studies and application of MFCs in environment monitoring field were reviewed,and main existing problems were analyzed,so as to provide reference for future study.

燃料电池增程式动力系统能量管理策略研究

以某款纯电动客车为研究对象,以增加车辆续驶里程为目的,提出燃料电池增程式混合动力系统结构,根据性能指标对动力系统各部件进行匹配计算和选型.提出了开关/功率跟随式能量管理策略,基于Cruise和Simulink分别搭建了整车动力系统模型和燃料电池及能量管理策略模型并进行联合仿真.结果表明,采用文中提出的能量管理策略车辆经济性相对于开关式和能量跟随式两种控制策略分别提高62%和31%,续驶里程相对于该两种控制策略分别提高41%和18%.

Hydrogen Smart-Grids: Smart Metering of Electricity from Hydrogen Fuel Cells

In the last decade, increasing applications of information technology (IT) within power industry has become a significant reality. As distributed power networks are gaining importance and renewables are getting a bigger ratio within energy production, Smart Grid applications have become essential, especially due to the intermittent nature of renewable energy resources. Smart Grid is a sustainable energy system that measures, checks, and controls the generation, transmission, and consumption of electrical energy in grids on all voltage levels. Smart Grid experts are driving forward the development of effective communication and information technologies for the build-up of intelligent power supply networks. Examples of these are control systems for the realization of virtual power plants, intelligent consumer data acquisition systems, and smart distribution management systems. Fuel cell-based hydrogen electricity, in comparison to other renewable energy sources, is more stable and predictable. Yet hydrogen power and smart-grids have many application points, mainly as means of energy storage. This study claims that hydrogen energy and smart-grids could also engage through an appliance of IT managed metering of hydrogen power production. Smart metering and management of hydrogen fuel cells would enable advanced planning of short-to-mid-term power productions and thus foster use of hydrogen power within distributed networks, as local community or industrial applications.

Nanoporous Silicon-Based Ammonia-Fed Fuel Cells

The objective of the paper is to report results on fabrication, structural, morphological and performance characteristics of novel TiO2/PS/Si, Au/TiO2/PS/Si and Au/PS/Si direct ammonia fuel cells (DAFC) using nanoporous silicon (PS) as proton conducting membrane (instead of traditional polymer Nafion membrane) and TiO2, Au/TiO2 or Au as catalyst layer. Porous silicon layers have been prepared by electrochemical modification of silicon substrates. Films containing titanium dioxide are more efficient catalysts for hydrogen production from ammonia solution. The Au/ TiO2/PS/Si cell exhibited the open circuit voltage 0.87 V and performance of 1.6 mW/cm2 with 50% ammonia solution as fuel at room temperature. Mechanisms of proton transport in nanoporous silicon membrane and generation of electricity in DAFC have been considered. Advantages of investigated direct ammonia fuel cells consist in simplicity of fabrication technology, which can be integrated into standard silicon micro fabrication processes and operation of cells at room temperature. The work demonstrates that the PS based fuel cells have potential for portable applications.

Energy-Nutrient-Water-Nexus by Microbial Fuel Cell: A Potential Smart Water Solution for Wastewater Treatment Plants

The Microbial Fuel Cell (MFC) is a bioelectrical system that can convert chemical energy into electrical energy. The anode plays an important role in the improvement of power generation. Zeolite and carbon-based materials were coated in graphene felt anode in this study for proof of concept that the modified material could enhance power generation. Preliminary results showed that the maximum power density with the modified material was 2 - 2.5 times higher than the unmodified material using RAS as a substrate and 1.4 times higher using algae as a substrate in our single chamber model, whereas the dual-chamber model displayed a maximum power density of the modified material to be roughly 3 - 4 times higher than in the unmodified microbial fuel cell.

燃料电池船舶混合动力系统能量管理研究综述

在“双碳”目标下,发展燃料电池船舶是实现航运业转型升级和低碳化的重要发展方向之一。面对当前燃料电池上船的诸多问题,混合动力系统成为燃料电池船舶应用的有效解决方案,其能量管理的研究也成为核心研究方向之一。系统梳理燃料电池船舶的发展概况,针对燃料电池船舶多类型能源能量管理中涉及的能量调度问题以及变换器功率分配问题进行综述;分析各类方法的优缺点及其在实船上应用的可能性;探讨燃料电池船舶推广可行性和发展方向,以期能为技术创新和工程应用提供参考。

An Experimental Study of Microbial Fuel Cells for Electricity Generating: Performance Characterization and Capacity Improvement

This paper studies the electricity generating capacity of microbial fuel cells (MFCs). Unlike most of MFC research, which targets the long term goals of renewable energy production and wastewater treatment, this paper considers a niche application that may be used immediately in practice, namely powering sensors from soils or sediments. There are two major goals in this study. The first goal is to examine the performance characteristics of MFCs in this application. Specifically we investigate the relationship between the percentage of organic matter in a sample and the electrical capacity of MFCs fueled by that sample. We observe that higher percentage of organic matter in a sample results in higher electricity production of MFCs powered by that sample. We measure the thermal limits that dictate the temperature range in which MFCs can function, and confirm that the upper thermal limit is 40℃. The new observation is that the lower thermal limit is -5℃, which is lower than 0℃ reported in the literature. This difference is important for powering environmental sensors. We observe that the electricity production of MFCs decreases almost linearly over a period of 10 days. The second goal is to determine the conditions under which MFCs work most efficiently to generate electricity. We compare the capacity under a variety of conditions of sample types (benthic mud, top soil, and marsh samples), temperatures (0℃, 40℃, and room temperature), and sample sizes (measuring 3.5 cm × 3.5 cm × 4.6 cm, 10.2 cm × 10.2 cm × 13.4 cm, and 2.7 cm × 2.7 cm × 3.8 cm), and find that the electricity capacity is greatest at 0℃, powered by benthic mud sample with the largest chamber size. What seems surprising is that 0℃ outperforms both room temperature and benthic mud sample outperforms marsh sample, which appears to be richer in organic matter. In addition, we notice that although the largest chamber size produces the greatest capacity, it suffers from efficiency loss. The reasons of these observations will be explained in the paper. The study demonstrates that the electricity production of MFCs can be increased by selecting the right condition of sample type, temperature, and chamber size.

功率分配方式对船用双堆燃料电池热管理效果分析

为研究船用双堆质子交换膜燃料电池(PEMFC)功率分配方式、热管理系统布置形式对热管理系统性能影响,基于AMESim软件建立了船用双堆PEMFC系统仿真模型,根据试验数据验证了仿真模型的可靠性。在此基础上,以串联式、并联式与旁通式热管理系统模型为研究对象,研究在变载工况下采用功率平均分配、逐级分配策略对电堆进出口冷却水温差的影响规律,最后比较在功率平均分配策略下3种热管理系统布置形式的性能。结果表明,3种热管理系统中电堆进出口冷却水温差均会在不同程度上受到功率分配策略的影响,在功率平均分配策略下,采用串联式热管理系统布置形式更有利于提高电堆内部温度一致性。