In a fuel cell, chemical energy is converted into a usable form of energy as fuel e. Usually linked with the hydrogen economy often chemically convert other fuels to hydrogen cost technology is complex fuel cells themselves may be. Unlike alkaline, phosphoric acid, and polymer electrolyte membrane fuel cells, mcfcs dont require an external reformer to convert more energydense fuels to. The efficiency of these type of fuel cells has risen to 50% in a combined electrical and steam cycle. The idea for this thesis was to design a specification of requirements for a fuel cell system for the electric power production in a 77foot sailing ship named ts prolific. The agency has also pursued other types of fuel cells, such as methane, metalair and hydrogen peroxide. Regenerative fuel cells can also be used with solar power or other sources of electricity to split water produced as a byproduct into hydrogen.
As a result, fuel cells can have different performance characteristics, advantages, and limitations, which can be suited to distributed generation applications in a variety of approaches. This follows last years field trials of diverse energys powercube technology in africa, and afc energys subsequent acquisition of assets from diverse energy equipment and ip and further project funding. A survey of current developments, 2007, fuel cells today 0. These are devices that, by definition, have an aqueous solution of sodium hydroxide or potassium hydroxide as the electrolyte. Design and test of a carbontolerant alkaline fuel cell. For example, the rocket engines of each shuttle flight burn about 500,000. Hospitals, credit card centers, police stations, and banks are all using fuel cells to provide power to their facilities.
A fuel cell is an electrochemical cell that converts the chemical energy of a fuel often hydrogen and an oxidizing agent often oxygen into electricity through a pair of redox reactions. When fuel is reformed by using reformer internally or externally it is known as reformer. Fuel cells by vijay ramani fuel cells are electrochemical devices that directly convert chemical energy to electrical energy. Afcs continued to be used on nasa space shuttles throughout the programme, alongside a limited number of commercial applications. The fuel is almost always hydrogen gas, with oxygen or oxygen in air as the oxidizer. Regenerative fuel cells can also be used with solar power or other sources of electricity to split water produced as a byproduct into hydrogen and oxygen in a process referred to as electrolysis. Proton exchange membrane fuel cell pemfc and alkaline fuel cell afc technologies have been. Jun 09, 2015 when most people think of fuel cells, companies like bloom energy, ballard, or fuelcell energy spring to mind. The alkaline fuel cell afc, also known as the bacon fuel cell after its british inventor, francis thomas bacon, is one of the most developed fuel cell technologies. A single fuel cell produces barely enough voltage for even the smallest applications. Design of a fuel cell system chalmers publication library cpl.
The materials used for electrolytes have their best conductance only within certain temperature ranges and. Capable of running on a variety of fuels, including hydrogen, natural gas, and. Early alkaline fuel cells afcs used liquid electrolytes like solutions of potassium or sodium hydroxide or diluted acids. Organization those involved in hydrogen and fuel cell technologies by type source. Fuel cells introduction fuel cells generate electricity from an electrochemical reaction in which oxygen from air and a fuel e. Understand the hazards, control the risks page 5 of 32 health and safety executive how fuel cells work 5 a fuel cell is a device for harnessing the energy liberated when hydrogen, or a hydrogenrich fuel, reacts with oxygen to produce water. Fuel cells are an energy producing alternative to conventional combustion engines. Think of a fuel cell like a battery in that it provides continuous dc electricity from a chemical reaction. A fuel cell is an electrochemical cell that converts the chemical energy of a fuel often. They consist of an electrolyte medium sandwiched between two electrodes fig. Black 15 gallon economy fuel cell made in usa by rjs with plastic cap at a great low price. Such electrodes for acid and alkaline fuel cells are described by. Cells pemfc, direct methanol fuel cells dmfc, alkaline fuel cells.
The fuel cell is composed of hot, concentrated potassium hydroxide surrounded by porous graphite electrodes. In such a manner, the production of hydrogen and its use in a fuel cell can be. Apr 26, 2016 it is a video based on alkaline fuel cell afc. Alkaline membrane fuel cells with insitu crosslinked ionomers yongjun lenga, lizhu wangb, michael a. Electrical energy input efficiency trend lines for alkaline. Fuel cell engine technology hydrogen fuel cell engines and related technologies. An overview of fuel cells currently under development. A conventional combustionbased power plant typically generates electricity at efficiencies of 33 to 35 percent, while fuel cell systems can generate electricity at. What links here related changes upload file special pages permanent link. Fuel cells can be divided into five major categories named after the electrolyte used in each. The first references to hydrogen fuel cells appeared in 1838. Like other fuel cells, regenerative fuel cells produce electricity from oxygen and hydrogen and emit heat and water as byproducts. Features of alkaline fuel cells glossary bibliography biographical sketch summary alkaline fuel cells use potassium hydroxide as the electrolyte. By definition, the process of any fuel cell could be reversed.
When most people think of fuel cells, companies like bloom energy, ballard, or fuelcell energy spring to mind. Fuel cells offer a highly efficient way to use diverse energy sources and, as a result, have demonstrated lower energy use and emissions when compared with conventional technologies. Design of an alkaline fuel cell mohammed alhassan, mohammed umar garba 100 the use of fuel cells in both stationary and mobile power applications can offer significant advantages for the sustainable energy conversion. The project to commercialize ammoniafed fuel cells for stationary power generation continues to gather momentum in europe, under the title project alkammonia. To increase the voltage, individual fuel cells are combined in series to form a stack. Other articles where alkaline fuel cell is discussed. A prelaunch malfunction of an oxygen feed control component not the proclaimed fuel cell problem was the real cause of the near disaster that attracted the attention of many millions of. With the centaur, apollo and space shuttle vehicles, nasa has developed extensive experience in the safe and effective handling of hydrogen. Normally, when hydrogen and oxygen react, a flame and heat energy are produced. Molten carbonate fuel cell mcfc they operate at 600c and can use co as a fuel input on the cathode side but need hydrogen on the anode. One electrode called the anode facilitates electrochemical oxidation of fuel, while the other called the cathode promotes. This type of fuel cell is the first generation fuel cell system that was employed as power sources in space vehicles.
However, because the presence of carbon dioxide degrades the cell. A workshop addressing the current stateoftheart in alkaline membrane fuel cells amfcs was held may 89, 2011, at the crystal gateway marriott in arlington, virginia. Nasa has used alkaline fuel cells since the mid1960s, in apolloseries missions and on the space shuttle alkaline fuel cells consume hydrogen and pure oxygen producing potable water, heat, and electricity. Low efficiency fuel crossover expensive catalyst 10xpt amount meoh wpoisonous example system bus m o t o r e e t c. Fcss based on three different fuel cell technologies are studied. A wide variety of alkaline fuel cell options are available to you, such as not powder. In the case of indirect fuel cell, the active fuel is obtained from a source and oxidized, example hydrogen obtained by hydrocarbon cracking. The space shuttle docks with the international space station in orbit. Progress and accomplishments in hydrogen and fuel cells pdf. Extraction of the energy proton exchange membrane fuel. This paper present the design of an alkaline fuel cell operating between 100250oc. Benefits arising from the use of fuel cells include efficiency and variability, as well as economy, unique operating conditions. An introduction to fuel cell technology and economics.
Pdf this paper present the design of an alkaline fuel cell operating between 100250oc. The temperature is high enough to be used for additional power production through cogeneration of steam. Hydrogen was bubbled into one arm while oxygen into the other. The alkaline fuel cell, also known as the bacon fuel cell after its inventor, has been. Alkaline fuel cells afcs were one of the first fuel cell technologies to be developed and were originally used by nasa in the space programme to produce both electricity and water aboard spacecraft. Extraction of the energy proton exchange membrane fuel cells. This section documents reasonable equipment performance.
A complete guide to alkaline fuel cell electrolytes. Just like batteries, a fuel cell has an anode, a cathode, and an electrolyte. In a letter dated october 1838 but published in the december 1838 edition of the london and edinburgh philosophical magazine and journal of science, welsh physicist and barrister sir william grove wrote about the development of his first crude fuel cells. The advantages the of use of hydrogenoxygen fuel cells for space applications was soon recognised and it was the only application which could afford them. This sectorwhich includes passenger cars, trucks, buses, and rail, marine, and air transportaccounts for more than 20 percent of americas energy use, mostly in. A regenerative fuel cell or reverse fuel cell rfc is a fuel cell run in reverse mode, which consumes electricity and chemical b to produce chemical a. Alkaline fuel cells encyclopedia of life support systems. A survey of current developments, 2007, fuel cells today. Alkaline membrane fuel cells with insitu crosslinked ionomers. Nasa has used alkaline fuel cells since the mid1960s, in apolloseries missions and on the space shuttle. Intermediate temperature direct ammonia fuel cells jason c.
However, a given device is usually optimized for operating in one mode and may not be built in such a way that it can be operated backwards. These fuel cells are clever pieces of technology that, like all other fuel cells, use electrochemistry to convert chemical energy into electrical energy. Distributed generation suitable for chp increased tolerance to fuel impurities expensive catalysts long startup time sulfur sensitivity. The fcss fuel processing subsystem includes a steam reforming reactor external to the fuel cell stack that converts natural gas into a hydrogenrich gas for the fuel cells. Table 61 provides a summary of the primary advantages and disadvantages of the various types of fuel cells. Fuel cells understand the hazards, control the risks. Unlike batteries, fuel cells cannot store electrical energy, and they dont require electricity to charge them.
The fuel cells and hydrogen joint undertaking fchju is a unique. Electrolyte membrane pem, direct methanol, alkaline, phosphoric acid, molten. The five types resulted from the knowledge that heat accelerates chemical reaction rates and thus the electrical current. Chapters 9 and 10 describe the mechanical and electrical components that make up the complete fuel cell plant for both stationary and mobile applications. Biographical sketch hiroko sotouchi was born on 26 february 1965, in japan, and received a bachelors degree in the. Proton exchange membrane fuel cells pemfc jens oluf jensen summer school on materials for the hydrogen society, reykjavik, june 19. The power produced by a fuel cell depends on several factors, including the fuel cell type, size, temperature at which it operates, and pressure at which gases are supplied. Further, the paper looks to introduce both the technical and economic issues facing the introduction of this technology.
Fuel cells are the most energy efficient devices for extracting power from fuels. Alkaline fuel cells, proceedings of 22nd intersociety energy conversion engineering conference iecec, philadelphia, pa, usa, p. The fuel cells are intended to complement the existing diesel generator, which is used to deliver power to the three phase system and to charge the batteries used for the low. Liquid fuel easy and fast fuelling easy and compact fuel storage disadvantages. This book offers those new to fuel cells a comprehensive, clear exposition and a. Oxygen reduction kinetics at ambient temperature is more rapid in alkaline electrolytes than in acid electrolytes, and the use of nonnoble electrocatalysts, in. To achieve improved performance, nasa is building on decades of success with gemini, apollo and shuttle alkaline fuel cell power system development and operations.
Nasa for decades, nasa has relied upon hydrogen gas as rocket fuel to deliver crew and cargo to space. Moltencarbonate fuel cells mcfcs are hightemperature fuel cells that operate at temperatures of 600 c and above molten carbonate fuel cells mcfcs are currently being developed for natural gas, biogas produced as a result of anaerobic digestion or biomass gasification, and coalbased power plants for electrical utility, industrial, and military applications. Alkaline fuel cells a fuel cell is an electrochemical device that can convert the chemical energy of hydrogen and oxygen directly into electric current. Here we have discussed about the definition,basic principle,application,advantages and disadvantages of afc.
Fuels for fuel cells most fuel cells use only pure hydrogen fuel not available in large quantities difficult to store, transport, transfer, etc. Wastewater treatment plants and landfills are using fuel cells to convert the methane gas they produce. The electricity produced can be used to power cars, buses, laptops and mobile phones. Fuel cells are different from most batteries in requiring a continuous source of fuel and oxygen usually from air to sustain the chemical reaction, whereas in a battery the chemical energy usually comes. In principle, the direction of the electrode reactions in alkaline water electrolysis is reversed in afcs.
The electrolyte in this fuel cell is concentrated 85 wt% koh in fuel. Global deployment of large capacity stationary fuel cells jrc. Usually linked with the hydrogen economy often chemically convert other fuels to hydrogen cost technology is complex fuel cells themselves may be only 25% of. Multiyear research, development and demonstration plan page 3. An alkaline fuel cell use alkaline electrolytes to produce electricity. Ganley howard university department of chemical engineering washington, dc. Figure 41 principles of operation of h2o2 alkaline fuel cell, immobilized. This workshop was the second of its kind, with the first being held december 11, 2006, in phoenix, arizona.835 836 381 96 223 416 1425 1027 1471 900 675 1230 171 532 114 161 1526 1150 50 625 283 167 1419 8 1148 673 716 1166 836 710 1136 446 261 180 883 612