Use of fuel cell

Several of the gas turbine cycle options discussed m this section (intercooling, recuperation, and reheat) are illustrated in Figure 4. These cycle options can be applied singly or in various combinations with other cycles to improve thermal efficiency. Other possible cycle concepts that are discussed include thermochemical recuperation, partial oxidation, use of a humid air turbine, and use of fuel cells. 

In contrast, your car s engine produces small amounts of air pollutants such as NO and copious amounts of C02, which contributes to global warming. On the other hand, there are a couple of deterrents to the use of fuel cells, i.e.—... 

The spurred impetus has been given to developing non pollutant vehicles, and consequently, the clean cars driven by the fuel cells loading proton exchange membranes (PEMFC), which based upon Nafion, have been surprisingly developed. A promising less pollutant and economical system is also expected, which will be the on site cogeneration system of electric power and the hot water supply with use of fuel cells combined with city gas pipe-lines. 

The use of fuel-cell vehicles does not always result in GHG emission reductions. For example, in the case of hybrid fuel-cell vehicles fuelled with CGH2 from the EU s current electricity mix and from hard coal lead to higher GHG emissions than hybrid ICE vehicles fuelled with crude oil based gasoline and diesel. 

Stationary use of fuel cells for the industrial and residential sectors is often foreseen in combined heat and power applications, but these are mainly run on syngas and/or natural gas instead of hydrogen. 

In addition to high-profile fuel cell applications such as automotive propulsion and distributed power generation, the use of fuel cells as auxiliary power units (APUs) for vehicles has received considerable attention (see Figure 1-9). APU applications may be an attractive market because it offers a true mass-market opportunity that does not require the challenging performance and low cost required for propulsion systems for vehicles. In this section, a discussion of the technical performance requirements for such fuel cell APUs, as well as the current status of the technology and the implications for fuel cell system configuration and cost is given. 

Several high-value niche markets drove early fuel cell technology development. These were the use of fuel cells for on-board electric power in space vehicles and to demonstrate that fuel cells are an efficient, environmentally-friendly technology for stationary on-site commercial power. 

Although several fuel cell technologies are reaching technical maturity, the economics of a fuel cell are not clear. The commercial potential of fuel cells will depend on the ability to reduce catalyst and other expensive materials costs and to manufacture the units at a competitive cost. Many uses of fuel cells place a premium on specific performance characteristics. The relatively simple alkaline fuel cells (AFC)... 

CFR), the International Code Council (ICC), the National Hydrogen Association, and the International Organization for Standardization (ISO), to name a few, will play a part in dictating the expanded use of fuel cell products. 

To conclude we may speculate on the future of the fuel cell research and make some observations. After much hope of achieving a cheap, reliable and efficient power conversion system, the hard facts of life have shown that the rapid commercialization and wide spread use of fuel cells cannot be obtained so readily. The level of R and D funding after the bonanza years of the moon flight missions rapidly decreased in the late sixties and several programs in industry came to a halt. The recent and exhaustive review by Kordesch ( 1). on fuel cell development indicates, among other things, that the peak in R and D in this field was in 1964. The maximum number of publications in fuel cell research activity occurred in 1969. 

In any case, an efficient transportation and distribution of hydrogen from the production site to the end-user is needed for the wide-spread use of fuel cells envisioned by the hydrogen economy. Key R D areas for improving hydrogen transportation and distribution infrastructure include ... 

Research on SOFCs started in 1990 for CHP applications and in 1992, PEM activities started to focus on CHP, traction and portable applications. Both types of systems are being actively pursued along with early demonstrations. Additionally, the use of fuel cells and bio-gas or biohydrogen is being evaluated. 

The most important use of fuel cells is in space vehicles (Apollo series). Liq hydrogen, hydrazine and ammonia have been used as fuel and liq oxygen as the oxidant Refs 1) G.Jf. Young St R.B. Rozelle, "Fuel Cells", JChemEduc 36(2), 68-73(1959)... 

It is well known that U.S. space vehicles obtain their auxiliaiy power in space by the use of fuel cells (Chapter 13), electrochemical devices in which the spontaneous tendency of hydrogen to combine with oxygen drives the cell and produces electricity, with water as a by-product (pure enough to drink). It stands to reason then, that one might think of producing substances more economically valuable than water in this electrogenerative way. Such work is into its first decade and Fig. 7.190 shows an example benzene is oxidized to phenol with electricity as a by-product Clearly, the economics of such a process depend on the cost of the H2 and whether one can sell the electricity. This gives rise to a speculation. 

Several schemes have been put forth in the past for desalinization by use of electrolysis. They had been discarded because of the large amounts of energy required. The idea was resurrected in anticipation of much more efficient recovery of energy through the use of fuel cells. 

Fuel cells require a steady supply of hydrogen. Therein lies the biggest problem in promoting the widespread use of fuel cells how to create, transport and store the hydrogen. At present, no one has been able to put a viable plan in place that would create a network of hydrogen fueling stations substantial enough to meet the needs of everyday motorists in the U.S. or anywhere else. 

So, despite much hype to the contrary, a hydrogen economy is a long way off. Widespread use of fuel cells, particularly for stationary applications, may be just around the corner, however, so they are the subject of the next two chapters. 

Fuel cells did not boom again for more than 50 years, although there was occasional activity in Europe. Then another person appeared on the scene, a man in the same vein as Sir William Grove, but much, much more persistent. This was Francis Thomas Bacon, and since it was he who stood directly behind NASA s use of fuel cells in the space flights, it can truly be said that more than any other individual, it was... 

The use of fuel cells on the Gemini series (and all subsequent) space flights run by NASA is well known. However, there are no diurnal variations of solar light in space, so that photovoltaics can provide the power for most space stations (as in the Russian Mir ) and on longer space flights. 

The first practical use of fuel cells was to provide auxiliary power in space vehicles. What was the principal reason for this choice Considering fuel cells runningon H2 and air 02, supplied by the re-forming of CH4 or CH3OH, discuss the various fuel cell types and suggest what applications will be made of re-formed H. (Bockris)... 

A concurrent development has been the proposed use of fuel cells integrated with gas turbines, as a power production route. The use of complete fuel cells in such a system would lead to high efficiency, and accordingly the system is reviewed. 

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