Power island

As shown in Figure 11.21, the power island of an IGCC plant consisted of GTs that use syngas as fuel, an HRSG, and steam turbines. Additional condensers, feed water heaters, and compressors are also essential parts of the steam power cycles. 

The conceptual layout of the power island was prepared to facilitate the Factory Cost estimation. As shown in Figure 2, the power island consists of 8 sections each containing 42 fuel cell modules. The module Sections are grouped with 4 Sections on each side of the centralized Power Island equipment. The footprint of the IGFC plant was found to be comparable to an IGCC plant. Recent Factory Cost Estimates have shown an SOFC power island cost of 635/kW in 2007 US dollars, meeting the DOE cost target of < 700/kW. 

Figure 2. Baseline IGFC Plant Power Island Layout...

Hydrogen LLC is developing a modular PAFC core unit of 400 kW, comprising of 4 x 100 kW stacks. These units can operate in series up to a 6MW Power Island , though the standard product will be a 2 MW unit. 

Figure XVIII-2 shows how a surface reaction may be followed by STM, in this case the reaction on a Ni(llO) surface O(surface) + H2S(g) = H20(g) + S(surface). Figure XVIII-2a shows the oxygen atom covered surface before any reaction, and Fig. XVIII-2h, the surface after exposure to 3 of H2S during which Ni islands and troughs have formed on which sulfur chemisorbs. The technique is powerful in the wealth of detail provided on the other hand, there is so much detail that it is difficult to relate it to macroscopic observation (such as the kinetics of the reaction).

Fig. 3. (a) General locations of hydrothemial power plants in the continental United States (6). Power is produced directiy from hydrothermal steam indicated by the steam plume at The Geysers in northern California. At all other locations, hot water resources are utilized for power production. In 1993, a hydrothermal power plant also came on line on the island of Hawaii, (b) Location of The Geysers steam-dominated hydrothermal field (D) in Lake and Sonoma counties, within the boundaries of the Cleadake—Geysers thermal anomaly (B). 

Nuclear power has achieved an excellent safety record. Exceptions are the accidents at Three Mile Island in 1979 and at Chernobyl in 1986. In the United States, safety can be attributed in part to the strict regulation provided by the Nuclear Regulatory Commission, which reviews proposed reactor designs, processes appHcations forUcenses to constmct and operate plants, and provides surveillance of all safety-related activities of a utiUty. The utiUties seek continued improvement in capabiUty, use procedures extensively, and analy2e any plant incidents for their root causes. Similar programs intended to ensure reactor safety are in place in other countries. 

The accident at the Three Mile Island (TMI) plant in Pennsylvania in 1979 led to many safety and environmental improvements (4—6). No harm from radiation resulted to TMI workers, to the pubHc, or to the environment (7,8), although the accident caused the loss of a 2 x 10 investment. The accident at the Chernobyl plant in the Ukraine in 1986, on the other hand, caused the deaths of 31 workers from high doses of radiation, increased the chance of cancer later in life for thousands of people, and led to radioactive contamination of large areas. This latter accident was unique to Soviet-sponsored nuclear power. The Soviet-designed Chemobyl-type reactors did not have the intrinsic protection against a mnaway power excursion that is requited in the test of the world, not was there a containment building (9—11). 

Investigation of Potential Hazar ds fr om the Oper ations in the Canvey Island/ Thurrock Ar ea, HMSO, London, 1978. Rasmussen, Reactor Safety Study An Assessment of Accident Risk in U.S. Commer cial Nuclear Power Plants, WASH-... 

Releases of radioactive materials from nuclear power plants have occurred, as at Three-Mile Island, Pennsylvania. In such situations, releases may be sufficient to require evacuation of residents. 

This node(s) presents a different problem. Its AC voltage can be easily capac-itively coupled into any adjacent traces on different metal layers, as well as radiate EMI. Unfortunately, it is generally the trace that must also act as a heatsink for both the power switch and the rectifiers, especially in surface mount power supplies. Electrically, the trace wants to be as small as possible, but thermally, it wants to be large. There is one good compromise in the surface mount designs, and that is to make the top PCB island identical to the bottom PCB island and connect them with numerous vias (or thru-hole connections). This can be seen in Figure 3-62. 

Chemical Industry - has risks comparable to or possibly greater then those of the nuclear power industry, but no risk studies of chemical plants in the U.S. have been published. Great Britain, on the other hand, has been active in this area, e.g., the Canvey Island Study (Section 11.4.1 and Green, 1982). 

The accident at Three Mile Island unfortunately tlircatened the future of nuclear power in tlie United States and called into question the safety systems... 

Everyone s worst fears about nuelear power beeaine a reality in tlie later part of April 1986. A large Soviet reaetor - unit number 4 at Chernobyl, 80 miles nortli of Kiev, and only 3 years old - blew out and burned, spewing radioaetive debris over mueh of Europe. Riidiation levels inereased from Sweden to Britain, tlu-ough Poland, and as far soutli as Italy. The damage eaused to tlie environment far surpassed tliat due to tlie aeeident at Tliree Mile Island. 

Advances in teclmology liai e brought about new problems. Nuclear power plant accidents (Tliree Mile Island and Chernobyl) have been the most frightening, perliaps because no one really knows what to expect from them. 

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