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The Enrico Fermi Nuclear Generating Station is a nuclear power plant on the shore of Lake Erie near Monroe, in Frenchtown Charter Township, Michigan on approximately 1,000 acres. All units of the plant are operated by the DTE Energy Electric Company and owned (100 percent) by parent company DTE Energy. It is approximately halfway between Detroit, Michigan, and Toledo, Ohio. It is also visible from parts of Amherstburg and Colchester, Ontario as well as on the shore of Lake Erie in Ottawa County, Ohio. Two units have been constructed on this site. The first unit's construction started on August 4, 1956 and reached initial criticality on August 23, 1963, and the second unit received its construction permit on September 26, 1972. It reached criticality (head on) in June 21, 1985 and was declared commercial on November 18, 1988. The plant is connected to two single-circuit 345 kV Transmission Lines and 3 120 kV lines. They are operated and maintained by ITC Transmission. The plant is named after the Italian nuclear physicist Enrico Fermi, most noted for his work on the development of the first nuclear reactor as well as many other major contributions to nuclear physics. Fermi won the 1938 Nobel Prize in Physics for his work on induced radioactivity. On October 5, 1966, Fermi 1, a prototype fast breeder reactor, suffered a partial fuel meltdown, although no radioactive material was released. After repairs it was shut down by 1972.〔http://www.nrc.gov/info-finder/decommissioning/power-reactor/enrico-fermi-atomic-power-plant-unit-1.html〕 On August 8, 2008, John McCain was taken on a 45-minute tour of the plant, becoming the first actively campaigning presidential candidate to visit a nuclear plant.〔NucNet. (McCain Reiterates Support For Nuclear During Enrico Fermi Visit ). August 8, 2008.〕 ==Fermi 1== The 69 MWe prototype fast breeder reactor Fermi 1 unit was under construction and development at the site from 1956 to 1963. Initial criticality was achieved on August 23, 1963. On October 5, 1966 Fermi 1 suffered a partial fuel meltdown. Two of the 92 fuel assemblies were partially damaged. According to the United States Nuclear Regulatory Commission, there was no abnormal radioactivity release to the environment.〔NRC ("Fermi, Unit 1" ), NRC Website, 3 February 2011, accessed 17 March 2011.〕 Fermi 1 was a liquid metal (sodium) cooled fast breeder reactor design. It was capable of producing 200 megawatts thermal (MWt) power or 69 MW electrical power with 26% enriched metallic uranium fuel. The enriched uranium section of the reactor (core) was a 30 inch in diameter cylinder by 30 inches high and contained 92 fuel assemblies. The core was surrounded by 548 additional assemblies containing depleted uranium. These assemblies were about 2.5 inches square by about 8 feet tall. Only the core section contained the enriched uranium while depleted uranium was placed above and below within the assemblies. The core also contained 2 control rods and 8 safety rods. The plant was designed for 430 MWt and 125 MWe using a newer uranium oxide fuel, but the plant was closed before the fuel was ever ordered. The shield plug was a rotating part of the inner reactor vessel and sat over the fuel. It could be rotated in order to facilitate fuel movements. The shield plug also provided radioactive shielding. During fuel loading, new assemblies were lowered down a tube into an adjacent Transfer Rotor which was integral with the reactor vessel. Then an Offset Handling Mechanism lifted the assembly from the Transfer Rotor and placed it into the vessel. Once all of the assemblies were loaded, a Hold Down Mechanism sat atop them so as to prevent them from moving upwards during operation. The Hold Down Mechanism also contained temperature measuring devices (resistance temperature detectors) to monitor sodium outlet temperatures from the assemblies. The (primary) sodium which flowed through the core exchanged heat with a secondary sodium system which then exited the containment. The secondary sodium then passed through the tube side of 3 parallel steam generators and transferred heat to water on the shell side. The “once through” design produced superheated steam which turned the main turbine-generator. A 168 MWe oil fired boiler was added in 1966 to utilize the turbine-generator during periods when the reactor was not producing power. The main cause of the partial meltdown was due to a temperature increase caused by a blockage in one of the lower support plate orifices that allowed the flow of liquid sodium into the reactor. The blockage caused an insufficient amount of coolant to enter the fuel assembly; this was not noticed by the operators until the core temperature alarms sounded. Several fuel rod subassemblies reached high temperatures of around (with an expected range near 580 °F, 304 °C), causing them to melt.〔 Following an extended shutdown that involved fuel replacement, repairs to vessel, and cleanup, Fermi 1 restarted in July 1970 and reached full power. Due of lack of funds and aging equipment it was finally decided to shut down permanently on November 27, 1972. It was officially decommissioned December 31, 1975 under the definition of the Atomic Energy Commission. Later, the Nuclear Energy Commission replaced the AEC and under their new definitions, Fermi was re-designated as being in SAFSTOR due to some remaining radioactivity at the site. On May 16, 1996, decommissioning was restarted. However, by November 2011 with very little activity remaining, a decision was made to halt further work. It is currently in SAFSTOR.〔 A number of accounts of the accident are available. One book is ''Fermi-1 New Age for Nuclear Power''〔ISBN 0-89448-017-0〕 and published by the American Nuclear Society in 1979. A book, ''We Almost Lost Detroit'', was written by local Detroit newsman John Grant Fuller (subtitled "This Is Not A Novel" to point out that it was not a work of fiction).〔Originally published 1975 by Reader's Digest Press, republished 1984 by Berkley, ISBN 0-425-06700-9〕 The song "We Almost Lost Detroit", by Gil Scott-Heron is also about the Fermi 1 meltdown. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Enrico Fermi Nuclear Generating Station」の詳細全文を読む スポンサード リンク
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