Space program, fuel cells

Advances in fuel cells were later accelerated by space and defense programs. Fuel cells found initial practical application with the Gemini (1962-1966) and the Apollo (1968-1972) spacecraft missions, and are still used to provide water and electricity for the Space Shuttle. The upgrade in fuel cell performance over the last four decades has been based on the development of new proton-conducting polymers, like Nafion and Gore-tex , ceramics and catalysts, as well as on greater insights into... 

Although the principle of fuel cells has been known since 1838, practical applications arc fairly recent. The first applications were in the space program, where fuel cells powered the Gemini and Apollo spacecraft. In the 1960s and 1970s, fuel cells... 

Finally, the energy available from the above reaction might be used to operate a fuel cell such as those involved in the space program. In that case, as much as 818 kj/mol of useful electrical work could be obtained relatively litde heat is evolved. Summarizing this discussion in terms of an energy balance (per mole of methane reacting) ... 

A fuel cell is a voltaic cell in which a fuel, usually hydrogen, is oxidized at the anode. At the cathode, oxygen is reduced. The reaction taking place in the alkaline fuel cells used in the space program since the 1960s is... 

Alkali fuel cells containing KOH and platinum- and gold-coated electrodes were developed for the space program, but these are too expensive for down-to-earth vehicles. In addition, these cells require pure oxygen rather than CO2 -containing air. 

The fuel eell is a nineteenth eentuiy invention in the twentieth eentury it heeame the heart of an eleetroehemical power plant and power souree, whieh is now in a stage of advaneed technology development. Its first and only applieation since the early 1960s, has been as an auxiliary power souree for spaee flights by the National Aeronautics and Space Administration (NASA). During the past decade, development for terrestrial (eivihan and defense) applieations has led to its commercialization and research on utilization in a variety of applications. Programs in the United States, Japan, Europe, and some other eoimtries are focused on the development of fuel cell power plant/power sources for (1) base-load,... 

Alkaline fuel cells (AFCs). The electrolyte is 40 to 70% KOH, the working temperatures are 60 to 240°C. Such systems were used in the spacecraft of the Apollo program and in the U.S. space shuttle. 

After it has been separated, hydrogen is an unusually clean-energy carrier and clean enough for the U.S. space shuttle program to use hydrogen-powered fuel cells to operate the shuttle s electrical systems while the by-product of drinking water is used by the crew. 

Low-cost material programs include the European Union s 54 million sixth framework research program on nanotechnologies and nanosciences, knowledge-based multifunctional materials, new production processes and devices. In partnership with the European Space Agency (ESA), the 5-year project seeks to find catalysts less expensive than platinum, which is used widely in fuel cells. As an alternative to platinum, nickel, cobalt and copper alloys are a possible solution. 

Fuel cells are not being installed in more applications because of their cost. The fuel cells used in the space program were extremely expensive at 600,000/kW and impractical for most power applications. But, over the decades, significant efforts have made them more practical and affordable. 

The application of fuel cells in the space program (1 kW PEFC in the Gemini program and... 

There is now a great interest in developing different kinds of fuel cells with several applications (in addition to the first and most developed application in space programs) depending on their nominal power stationary electric power plants (lOOkW-lOMW), power train sources (20-200kW) for the electrical vehicle (bus, truck and individual car), electricity and heat co-generation for buildings and houses (5-20 kW), auxiliary power units (1-100 kW) for different uses (automobiles, aircraft, space launchers, space stations, uninterruptible power supply, remote power, etc.) and portable electronic devices (1-100 W), for example, cell phones, computers, camcorders [2, 3]. 

The PEMFC is nowadays the most advanced low-temperature fuel cell technology [19, 20], because it can be used in several applications (space programs, electric vehicles, stationary power plants, auxiliary power units, portable electronics). The progress made in one application is greatly beneficial to the others. 

Besides high efficiency, fuel cell driven engines offer noiseless and clean operation. Nitrogen oxides, the only pollutants emitted by hydrogen 1C engines, are not produced by a fuel cell. Fuel cells have been effectively used in space programs where they... 

Alkaline fuel cells (AFCs) were one of the first fuel cell technologies developed, and they were the first type widely used in the US space program to produce electrical energy and water onboard spacecraft. These fuel cells use a solution of potassium hydroxide in water as the electrolyte and can use a variety of non-precious metals as a catalyst at the anode and cathode. High-temperature AFCs operate at temperatures between 100°C and 250°C. However, more-recent AFC designs operate at lower temperatures of roughly 23°C to 70°C. 

Apart from being a constituent of rocket fuels, it is used to remove oxygen from boiler water to prevent the corrosion of the vessels. If, as some believe, hydrazine-based fuel cells eventually come into commercial use, demand will be enormous. Hydrazine hydrate production in noncommunist countries now stands at about 25000 metric tons per year, of which 17000 metric tons are used by the US with about 7000 metric tons taken by the space programs. 

The fuel cell is nothing new, despite the excitement it is now generating. It has been around since 1839, when Welsh physics professor William Grove created an operating model based on platinum and zinc components. Much later, the U.S. Apollo space program used fuel cells for certain power needs in the Apollo space vehicles that traveled from the Earth to the Moon. 

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