燃料电池（FC）联合循环发电系统的开发现状及展望

燃料电池是一种能将燃料化学能直接转化成电能的装置,燃料电池发电装置对电工工业具有很大的吸收引力,将成为２１世纪的新能源。本文主要讨论了高温燃料电池的构成与原理以及燃料电池的联合发电系统,同时还叙述了美国等其他国家燃料电池的开发现状以及对燃料电池的开发现状以及对燃料电池未来的展望。     

燃料电池发电的电站应用

燃料电池作为一种高效稳定的分布式清洁能源,其发电技术在电站领域的应用备受关注,而国内燃料电池电站尚在起步阶段,因此对这一领域的研究和实践经验具有重要意义。基于韩国燃气轮机联合循环电站中燃料电池发电项目的实施,介绍了燃料电池的选型,并通过模拟运行确定了最佳余热回收方案。MCFC燃料电池额定发电效率为47%,余热回收后效率提高3.5%。这些经验将对国内未来燃料电池电站的建设起到参考和借鉴意义。     

高温燃料电池发电系统研究

介绍燃料电池的分类和应用技术路线,比较各种燃料电池的发电特性,分析高温燃料电池的应用前景。分析表明,固体氧化物燃料电池在大型电厂的应用具有潜在优势。应用稳态模拟软件(AspenPlus)对1000kW SOFC/GT发电系统进行了模拟,模拟结果与WestingHouse 500kW SOFC/GT发电系统设计数据比较吻合,误差小于5%。应用建立的系统模型对影响系统性能的主要参数进行了优化,系统效率提高到51.403%。     

太阳能光伏制氢储能——燃料电池发电系统

20年来,我国太阳能光伏发电技术的开发利用取得了巨大成绩。特别是通过“七五”、“八五”科技攻关项目的实施,太阳能光伏发电的技术水平与实用化程度有了显著提高,其应用范围和规模不断扩大。光伏发电在解决边远地区人民生活用电和某些生产用电方面起到了重要作用,取得了良好的经济效益和显著的社会效益。随着经济的发展和人民生活水平的不断提高,边远地区居民对电视机、洗衣机、电冰箱等家用电器的购买欲望日益强烈,同时对供电质量,供电的保证率也提出了新的要求。我国现有的太阳能光伏发电系统基本上是独立方式运行,系统供电受季…     

燃料电池发电技术综述

介绍了燃料电池及其发电原理和机组构成,产针对当前的燃料电池在国际上的发展情况,讨论燃料电池所存在的问题,指出其今后发展及研究方向。     

生物质气化—燃料电池发电系统性能分析

建立了基于热力学平衡的生物质气化模型,利用平衡模型分析了气化过程的特性,研究了气化过程的反应规律及各种因素对气化性能指标的影响,详细分析了当量比及物料湿度对气体产物成分及气化产物热值的影响.同时,建立了以生物质气为燃料的固体氧化物燃料电池的数学模型,该模型考虑了燃料电池的能斯特电动势及各种极化损失.利用建立的模型分析了操作参数以及物料湿度和生物质种类对生物质气化—燃料电池发电系统性能的影响.结果表明,生物质气化—燃料电池发电系统的发电效率可达30％,热电联产效率最高可达95％以上.     

一种新的发电方式——燃料电池发电

本文介绍燃料电池发电的基本概念、现状、特点,有关燃料电池发电的主要设备、燃料、流程及展望。     

高温燃料电池与燃气轮机相结合的混合发电系统

高温燃料电池与燃气轮机相结合的混合发电系统具有高效、环保和可靠的特性,这种新颖的混合发电系统在未来分布式发电领域具有广阔的应用前景。有不少专家和学者对其系统构成度匹配、系统性能等问题做了大量研究。目前已有高温燃料电池与燃气轮机混合发电系统成功运行,但仍有很多问题需要进行进一步的研究和探索,以使该混合发电系统早日实现商业化运行。本文综述了高温燃料电池与燃气轮机混合发电系统的研究现状,展望了该混合发电系统在未来的研究度发展前景。     

燃料电池发电技术的发展综述

燃料电池的原理始于1939年Grove发表的论文中提出氢和氧反应可发生电的理论,(即水电解为氢和氧的逆反应)。但直到60年代为适应宇航事业的需要才开始应用,并不惜工本开发出应用液氢和液氧的燃料电池。1967年美国将它列入天然气转换研究计划,着手开发以天然气为燃料的民用燃料电池,并吸收美国各大煤气公司和日本的大阪和东京煤气公司参加。70年代初,对环保的重视和发生世界性的石油危机,这种污染少     

3．生垃圾燃料电池发电系统

日本每年大约排出2000万吨生垃圾,大部分进行焚烧或填埋处理。但焚烧会产生二恶英类物质,填埋处理场紧迫,还有恶臭等问题,必须寻求环境负荷少的新处理方法。鹿岛建设在垃圾处理方面,开发了以生物气体为能源,可回收高温甲烷发酵式有机废弃物处理系统,商品名为“甲烷克莱斯”。     

有轨电车用燃料电池系统效率研究

文章基于100 kW燃料电池试验平台,对燃料电池系统的辅机功耗及系统效率进行了研究。通过启动、稳态和加减载3个试验,研究了不同工况下辅机功耗以及系统效率。研究结果表明:最小功率启动时,燃料电池的功率不足以维持辅机工作,需要外部电源提供差额功率;在散热良好条件下,额定功率时压缩机、散热器、循环水泵和氢气回流泵的功耗分别占电堆功率的12.3%,1.10%,0.70%,1.06%;用电效率、发电效率和系统效率分别为85.0%,54.1%,46.0%;随着电堆功率的增长,发电效率降低,用电效率和系统效率存在最优值。     

Maximum conversion efficiency of hydrogen fuel cells

Çengel and Boles discuss in their Thermodynamics textbook that the Carnot efficiency bound is not applicable to fuel cells, whereas some researchers have raised objection that maximum conversion efficiency of fuel cells is limited to the Carnot efficiency. We apply the conservation of energy and entropy balance equations to derive expressions for the maximum work of hydrogen-oxygen, hydrogen-air and methane-air fuel cells. We show that the theoretical efficiency of a fuel cell may exceed that of a Carnot engine operating between the same low and high temperatures. Contrary to past studies in that the efficiency of an ideal hydrogen fuel cell is shown to decline with temperature, the maximum efficiency is observed to first decrease with reactants temperature, then remains unaltered and finally rises. The lowest value of the maximum efficiency is found to be 79.3%, 75.7%, and 82.1% for hydrogen-oxygen, hydrogen-air and methane-air fuel cells, respectively. By increasing the stoichiometric coefficient of air, the efficiencies of both hydrogen-air and methane-air fuel cells monotonically increase and they approach the 100% limit at a stoichiometric coefficient of 7.2 and 9.8, respectively. It is shown that a Carnot engine whose heat is supplied by an isothermal combustor proposed in some past studies is not a correct means for comparison of the ideal performance of fuel cells and heat engines.     

基于替代燃料的燃料电池内燃机混合动力系统方案探讨与性能浅析

通过平衡燃料电池和内燃机的优劣势,构建了由燃料电池和内燃机组成的基于替代燃料(氢气、天然气、甲醇、液氨)的混合动力系统,分析了不同系统的发电性能,评估了其技术实现难易程度。结果表明：质子交换膜燃料电池内燃机混合动力系统中,当质子交换膜燃料电池和内燃机燃料流量相同时,该工况下系统的发电效率可达到40%以上;以甲烷为燃料的固体氧化物燃料电池内燃机混合动力系统的发电效率最高,达到了62.24%,以液氨为燃料的固体氧化物燃料电池燃料消耗率最低,为313.04 g/(kW·h)。     

沼气发电技术及沼气燃料电池在我国的应用状况与前景

沼气发电技术是一种清洁的发电技术。文章针对目前我国已有的沼气发电技术进行了技术评价,综述了这种技术的发展现状与近年来的应用情况;燃料电池也是一种新型高效、清洁的发电技术,文章对以沼气为燃料的燃料电池技术进行了介绍,对我国沼气利用技术的发展具有参考价值。     

生物质气化高温燃料电池一体化发电技术研究

介绍了国内外生物质气化高温燃料电池一体化发电技术的研究现状，主要包括高温燃料电池的特点和研究现状；一体化发电技术的理论模拟；国外相关的试验研究和一体化示范工程。分析了生物质气化高温燃料电池一体化发电技术在我国应用的可行性，提出了目前需要解决的关键技术问题。     

Conceptual design of a novel ammonia-fuelled portable solid oxide fuel cell system

A novel portable electric power generation system, fuelled by ammonia, is introduced and its performance is evaluated. In this system, a solid oxide fuel cell (SOFC) stack that consists of anode-supported planar cells with Ni-YSZ anode, YSZ electrolyte and YSZ-LSM cathode is used to generate electric power. The small size, simplicity, and high electrical efficiency are the main advantages of this environmentally friendly system. The results predicted through computer simulation of this system confirm that the first-law efficiency of 41.1% with the system operating voltage of 25.6 V is attainable for a 100 W portable system, operated at the cell voltage of 0.73 V and fuel utilization ratio of 80%. In these operating conditions, an ammonia cylinder with a capacity of 0.8 l is sufficient to sustain full-load operation of the portable system for 9 h and 34 min. The effect of the cell operating voltage at different fuel utilization ratios on the number of cells required in the SOFC stack, the first- and second-law efficiencies, the system operating voltage, the excess air, the heat transfer from the SOFC stack, and the duration of operation of the portable system with a cylinder of ammonia fuel, are also studied through a detailed sensitivity analysis. Overall, the ammonia-fuelled SOFC system introduced in this paper exhibits an appropriate performance for portable power generation applications.     

What is the design objective for portable power generation: Efficiency or energy density?

Recently, various alternatives to batteries, such as microfabricated fuel cell systems, have been proposed for portable power generation. In large-scale power production plants emphasis is placed on energy conversion efficiency. On the other hand, the intrinsic design objective for portable power generation devices is the energy density, i.e., the electrical energy generated from a given mass or volume of device and fuel cartridge. It is plausible to stipulate that an increase in the energy conversion efficiency of a system leads to an increase in energy density, but we demonstrate through theoretical analysis and case studies that the two metrics are not equivalent. In some cases, such as systems with a combination of fuels, maximizing efficiency leads to drastically different design, operation and performance than maximizing energy density. Another interesting observation is that, due to interaction between components, maximal component efficiency does not always imply maximal system efficiency.