| September 29, 2006 Going Nuclear US, Alaska Interested In Revisiting Nuclear Age Part Two of a Two Part Series by Brian Yanity, insurgent49  As
the technology is presently used, nuclear energy is not a renewable
source of energy. Uranium oxide, the natural mineral that is mined and
refined into nuclear fuel, is a finite resource. This non-renewable energy resource could be greatly extended, however, through highly efficient nuclear reactors, such as “fast breeders”. The nuclear reactor proposed for the Alaska town of Galena is a result of fast breeder reactor research, and would be a much different animal than the existing water-cooled reactors that are standard at nuclear power plants today. Security of the Nuclear Fuel Supply Australia has the world’s largest uranium reserves, with 40% of known deposits. At present, Canada is the world’s leading producer of uranium oxide ore. In particular, the mines in the Athabasca Basin of northern Saskatchewan and Alberta provide almost 30% of the world’s uranium production. Significant uranium ore reserves are also found in Kazakhstan, Russia, Brazil, South Africa, Namibia and Niger. The US posses 7% of the world’s uranium reserves, mostly in the states of Wyoming, Colorado, Utah, New Mexico and Arizona, but only 2.5% of the world’s uranium production is in the US. Uranium oxide is even found in parts of Alaska. For example, the Bokan Mountain uranium oxide mine operated on Prince of Wales Island from 1957 until 1971, though most of its ore was very low grade. Once mined, uranium oxide must be enriched to increase its content of the isotope uranium-235 from 0.7% to 3 or 4% before it can be made into reactor fuel pellets. International nuclear fuel supplier countries include the US, Russia, France, and the UK. In addition to the world’s 440 existing reactors, about 70 more are under construction or in the planning stages. With this increase in demand, the price of uranium rose from $7/lb. in 2001 to $52/lb. by September 2006. These prices have caused parts of the desert southwest and Rocky Mountain states to see a revival in uranium mining. For nuclear energy production, there are two main ways, or cycles, of consuming uranium fuel: Open-fuel cycle: The uranium is “burned” once in a reactor, and then the spent fuel is stored permanently in a geologic repository. Most nuclear power reactors in use today use an open-fuel cycle, and the average 1000-megawatt (MW) power reactor will consume between 4000 and 6000 short tons of uranium oxide over its 30-year lifespan. The open-fuel cycle avoids the nuclear proliferation problem, but it uses less than 1% of the energy contained in the uranium. Closed-fuel cycle: Also called the “plutonium cycle”, the closed-fuel cycle involves the reprocessing of spent fuels, and enables the re-use of spent uranium fuel. The spent fuel includes the element plutonium, which can be chemically extracted and turned into fuel for another reactor. As part of a closed fuel cycle, reprocessing can recover up to 95% of the remaining uranium and plutonium in spent nuclear fuels. However, the recycled fuel is more expensive than the original uranium. Spent nuclear fuel rods can be chemically processed to separate plutonium, which can be accumulated until there is enough to build a bomb. A nuclear fuel reprocessing plant separates any usable elements, such as uranium and plutonium, from fission products and other materials in spent nuclear reactor fuels. The first nuclear fuel reprocessing plant was built in 1963. Reactor-grade plutonium is the most common high-level waste from nuclear reactors. However, most fission products are relatively short-lived. High-level radioactive waste from nuclear power plants is stored temporarily in spent fuel pools for a period of five years and, once it has cooled down, is placed in on-site dry cask storage facilities. The prospects of recycling nuclear fuels also include converting all the “transuranic actinide” elements, such as plutonium. When this is done, nearly all the long-lived wastes are eliminated. However, the volume of space needed for waste storage in this scenario does not decrease, only the radioactivity/toxicity level of the waste decreases. This plutonium can be used as fuel in fast breeder reactors (read below). France in particular uses a mixture of plutonium and uranium oxides, which are “burned” again in its nuclear power reactors. Another possible benefit of reprocessing is that it extends the useful lifespan of natural uranium fuel supplies, but does not make nuclear fission a “renewable” energy source. The world’s estimated nuclear fuel reserves, at projected rates of nuclear energy utilization using the open-fuel cycle, is about 50 years, though with use of fast breeder reactors. a closed-fuel cycle could extend this period to thousands of years. Since 1977, the policy of the US government is to not recycle spent nuclear fuels from power reactors due to fears of nuclear weapons proliferation (read below). One possible substitute for uranium as reactor fuel is thorium, an element that is about three times as abundant in the Earth’s crust as uranium. In a thorium reactor, the isotope Thorium-232 absorbs a slow neutron to form Uranium-233, which is then burned as fuel. Despite three decades of research however, no commercial thorium reactor has yet been constructed. India has particularly large reserves of thorium, and is presently conducting research on an advanced heavy water reactor (AHWR) designed to run on thorium. A nuclear power reactor cannot explode like a nuclear bomb, but any nuclear fission fuel (uranium-233, uranium-235 or plutonium-239) can be used to make a fission weapon if it is highly enriched (more than 90%). The processing that occurs in a closed-fuel cycle results in enriched plutonium which can be used for nuclear weapons production. A typical light water reactor at a commercial nuclear power plant produces 500 pounds of plutonium per year, while it only takes 20 pounds of plutonium to make an atomic bomb. The amount of the isotope plutonium-239 of a spent uranium fuel rod is about 0.6% (by weight) of the fuel rod loading. High-speed centrifuge technology now allows nations to produce weapons-grade plutonium without a reactor. The only proven methods of keeping enriched nuclear materials out of the “wrong hands” are material accountability, physical security of nuclear facilities, containment and surveillance. Nuclear terrorism could be possible in many different ways, from “dirty bombs” of a conventional explosive used to spread radioactive materials, to full-blown nuclear weapons. Also, it is still uncertain whether or not reactor buildings could withstand impacts from large airplanes or other types of attack. On an interesting side note, the uranium and plutonium within nuclear weapons is so enriched that dismantling these bombs can yield a lot of useful fuel for power reactors. Russia is already making money by selling uranium reactor fuel that has been extracted and diluted from dismantled nuclear warheads (www.usec.com/v2001_02/HTML/megatons.asp). Fast-Breeder Reactors First proposed by Manhattan Project scientists in the 1940s, fast-breeder reactors (FBRs) ‘optimize’ and speed up the plutonium reprocessing, but have not yet proven practical due to very high costs. In experimental power plants, FBRs can ‘breed’ more plutonium nuclear fuel than they consume, though they still face daunting technical and economic challenges. Existing thermal reactors (PWRs and BWRs), also called “burners”, use a neutron moderator to slow down neutrons within the fission reaction. An FBR is a type of fast neutron reactor, which does not need a neutron moderator.  Chinese FBR As opposed to present-day light water reactors that use uranium-235 (0.7% of all natural uranium oxide) for fuel, an FBR uses uranium-238 (99.3% of all natural uranium), provided enough uranium-235 is used to start up the process. Light water reactors require enriched uranium, which consists of 3 to 5% of U-235 by weight. Heavy water reactors use natural (un-enriched) uranium in ceramic form as fuels. To start up, an FBR needs uranium-238 fuel rods enriched to 15% or better. For an FBR using plutonium-239 as the fissionable fuel, the initial plutonium fuel would be supplied from a standard uranium-235 “burner” thermal reactor, but later the FBR would produce its own plutonium-239 from uranium-238. Under a full-scale breeder reactor program, plutonium-239 would be the basic fuel for the majority of U.S. reactors, and thus large amounts of highly toxic plutonium would be transported, handled and stored all across the country. The world’s first FBR was the Experimental Breeder Reactor (EBR-I) at what is now called the Idaho National Laboratory (www.inl.gov), located between the towns of Arco and Idaho Falls in the eastern part of Idaho along U.S. Highway 20. In December 1951, EBR-I became the first nuclear reactor in the world to generate electricity. EBR-I operated from 1951 until 1964, though suffered a partial meltdown due to operator error in 1955. The reactor is now a National Historic Landmark and is open to the public during the summer. Since 1949, 52 experimental reactors have been built on the 840 square mile reservation of the INL, although only three are currently operating. One of these, the Advanced Test Reactor, is being used to test new fuels and alloys in the extreme conditions within the next generation of reactors.  EBR-1, Idaho EBR-I’s successor was the sodium-cooled EBR-II, which operated at INL for three decades (1964 to 1994). A special series of safety tests were performed on EBR-II in 1986: primary cooling pumps were purposely shut off, and the reactor’s power output dropped to zero within five minutes. Since no damage to the fuel or the reactor resulted, this test demonstrated that even with a loss of all electrical power,the reactor will simply shut down without danger. EBR-II’s secondary cooling system was shut down in another test, causing the reactor temperature to increase. However, the heat caused the liquid sodium of the primary cooling system to expand, shutting down the reactor.  EBR-II The US Department of Energy’s next FBR project was to be the Clinch River liquid metal fast-breeder reactor (LMFBR) at the Oak Ridge National Laboratory in Tennessee (www.ornl.gov). The Clinch River FBR project was studied from 1984 until 1994, but was never completed. It was designed to produce 20% more plutonium-239 atoms than uranium-238 atoms that it burned up. For the first four decades of the US Government’s involvement in fast-breeder reactors, over $10 billion has been spent on research and development. The only commercial fast-breeder reactor ever built in the U.S. was the 94 MW Unit 1 at the Enrico Fermi Nuclear Generating Station near Newport, Michigan. Fermi-1 went into operation in 1963, but was shut down in 1972 after suffering a partial core meltdown in 1966. This event inspired Gil Scott-Heron’s song “We Almost Lost Detroit.” The Superphenix FBR, designed for nuclear power generation, operated in France from 1985 to 1996. This facility proved to be an economic disaster, and was closed for good in 1997. India built its first fast-breeder research reactor in 1985, and has a large FBR under construction. The SSTAR “small, sealed, transportable reactor”, being developed the U.S. Department of Energy’s Lawrence Livermore Laboratory in California (www.llnl.gov), and the 4S are described below. The Next Generation of Nuclear Reactors Various new reactor technologies are in the experimental stages. The first of the new generation of reactors to be built will be the advanced pressurized water reactors (APWRs), a new design of the PWR standard in nuclear power plants today. European Pressurized Reactor (EPR) is an APWR designed to use 5% enriched uranium oxide or mixed uranium plutonium oxide fuel. Developed mainly by French and German engineers, the first EPR is planned to come online in Finland by 2009, with a second EPR in France soon after. Liquid metal reactors can be cooled by liquefied lead or sodium, and were developed as part of fast breeder reactor (FBR) research. The first sodium-cooled reactors were FBRs built in the late 1950s. These reactors efficiently use neutrons to convert non-fuel materials into reactor fuel, extending the lifetime of the reactor’s uranium fuel. However, great care must be taken to ensure that the liquid metal does not come into contact with air or water. Other risks of using liquid sodium coolant include keeping it warm enough to be molten and the neutron interactions with sodium. When bombarded by neutrons, liquid sodium produces the highly radioactive isotope sodium-24, which is dangerous but has a short half-life compared to uranium or plutonium.  Sodium Cooling System First developed in Germany in the 1960s, pebble-bed reactors (PBRs) are a gas-cooled reactor design, in which the nuclear fission reaction takes place within ceramic balls or “pebbles” containing nuclear fuels such as uranium, plutonium, or thorium. These pebbles are contained within a can-shaped chamber cooled by inert gases such as helium, nitrogen or carbon dioxide. When the heated gas leaves the chamber, it directly or indirectly (via a heat exchanger) turns a turbine to produce electricity. PBR modules are being designed specifically for peaking-power generation, in contrast nuclear plants of today being designed as base-load plants (www.pbmr.com). The first pebble-bed reactor scheduled to be constructed in South Africa starting in 2007, with an on-line date around 2011. Commercial modules of 165 MW pebble bed reactors planned for as early as 2013, also to be manufactured in South Africa. PBR research efforts are underway in other several nations, including China and the Netherlands. In the U.S., $1.25 billion is has been allotted to construct an experimental PBR at INL by 2014. Nuclear fusion reactors have the potential to produce far greater amounts of energy than today’s fission reactors, while producing much smaller amounts of radioactive waste. The nuclear fusion reaction creates massive amounts of energy, and is the energy source which powers the stars. In fusion, lighter elements, such as hydrogen or tritium, fuse together to form heavier elements such as helium. For a future generation of fusion reactors, hydrogen isotope fuel such as deuterium and tritium are plentifully available from seawater. So far, only experimental fusion reactors have been built, and they yield small amounts of energy compared to the amount of power needed to start up the reaction. Controlled fusion reactions can also be obtained in nuclear physics laboratories using nuclear accelerators such torus-shaped tokamaks. The $10 billion International Thermonuclear Experimental Reactor (ITER) should begin operation in southeastern France in 2016. The ITER is expected to be the first fusion reactor that will generate far more energy than it consumes. Most experts agree that commercial power generation from nuclear fusion energy is at least 30 years away or longer. Small Reactor Proposal for Galena The nuclear installation proposed for the rural Alaska town of Galena is a 10-megawatt (MW) 4S reactor (Super Safe, Small and Simple) reactor under development by the nuclear power systems division of the Japanese conglomerate Toshiba (www.toshiba.co.jp/product/abwr/english/index.htm).  The 4S modular “battery” design is a sodium-cooled fast reactor operating at atmospheric pressure with ‘modular’ construction, i.e. mass produced units like airplanes or trucks. Galena’s 4S reactor would be located in a sealed, cylindrical vault 30 meters underground, while the building above ground would connect to the town’s electrical distribution system. The reactor will run on highly-enriched uranium or uranium-plutonium alloy fuel rods, with no refueling for 30 years, after which time the entire reactor will be replaced, presumably with a new 4S unit. The Galena plant’s spent fuel would be taken to the Yucca Mountain facility in Nevada, and its used reactor would go there or to a government nuclear site such as Hanford in Washington (www.hanford.gov).  4S Plant Installation At this point, it is unclear whether or not the 4S will be a true ‘breeder’ reactor, but it does represent a practical application of fast-breeder technology. The present-day 4S design was developed from U.S. breeder reactor technology, under contract to Toshiba and Japan’s Central Research Institute of Electrical Power Industry. Japan’s MONJU sodium-cooled fast breeder reactor was completed in 1994, but was permanently shut down in late 1995 after a sodium leak started a fire. Toshiba is the first corporation in the world to commercialize this technology, so nuclear energy experts from around the world will be following the progress of the Galena reactor project. If Galena succeeds in having the reactor licensed, Toshiba will install the reactor, with operations planned to start in 2014. Site permitting will take place between 2005 and 2007, permit application and NRC review between 2006 and 2010, and construction is scheduled to happen between 2011 and 2013. The estimates of the operating cost of the Galena nuclear power plant (not including permitting, design, and construction costs) are between 5 and 13 cents/kWh, which is about three times less than diesel-generated power at current prices. In this project succeeds, Toshiba plans to sell other 4S reactors to other towns in rural Alaska and around the world. Alaska’s mining industry has already expressed interest in small reactors powering their remote operations. The federal Nuclear Regulatory Commission (NRC), part of the U.S. Department of Energy, is responsible for the regulatory approval of all nuclear power plants in the country. An Early Site Permit (ESP) for a new reactor application is issued by the NRC after at least one to two years of data collection on a range of parameters. The ESP process has two main parts: site safety analysis and environmental report, including emergency planning and an environmental impact statement (EIS). The proposed Galena nuclear plant has a ‘passive safety’ design approach, relying on inherent feedbacks to balance heat production to heat removal and an always-operating, passive system to remove the fission product decay heat. The goal of such a design approach is to maintain a steady (non-growing) fission chain reaction, so the production of neutrons is balanced by their destruction (what went wrong at Chernobyl), and to remove heat even if the nuclear reaction stops (what went wrong at Three Mile Island).  Galena Plant Plans The Galena power plant’s reactor building is to be designed to contain radioactivity even in the event of an accident, with the shielding of the reactor from external damage and seismic isolation to protect it from earthquakes. The permitting of the Galena reactor site is being overseen by the Small Reactor Projects division of the engineering firm Burns and Roe Enterprises, Inc of New Jersey (www.roe.com), and the DC-based law firm of Pillsbury Winthrop Shaw Pittman. Proposed end-uses of the surplus nuclear energy in Galena include heating for city buildings, schools, the public swimming pool, and the health clinic. District heating is already used in the town from an existing combined heat-and-power (CHP) system powered by diesel. Ron Johnson, a mechanical engineering professor at the University of Alaska Fairbanks, was quoted in a December 28, 2004 Associated Press article as stating: "if the technology is successfully deployed in Galena, its economic viability in other Alaska villages and elsewhere depends on the actual life cycle costs, which are yet to be quantified.” If history is any guide, the 4S reactor system proposed for Galena will require numerous modifications to its design and operating procedures before it will be of use to the community. In addition to electricity production and heating, other uses have been proposed for small nuclear reactors including hydrogen production and saltwater desalination. Perhaps hydrogen could be produced in Galena using the surplus energy from the 4S reactor, and this hydrogen could in turn power vehicles such as trucks or snow machines. The federal Energy Policy Act of 2005 set aside $1.25 billion for an experimental electricity-hydrogen ‘cogeneration’ plant, using new nuclear reactors at the Idaho National Laboratory. Such a hydrogen-production plant would use the reactor to heat up the water, making electrolysis more efficient. Conclusion We must accept that fact that in the US, and in the world, there are many existing nuclear power plants, and resulting radioactive wastes, which are not going to go away any time soon. The safety regulations imposed on nuclear power facilities must be enforced diligently. A major focus of nuclear engineering must be on waste disposal, and the finding ways of reducing the likelihood of any type of nuclear accident. If the next generation of nuclear power reactors does indeed prove much safer that the last, then maybe the country’s energy future will have more to do with nuclear reactors developed in eastern Idaho than in the oil and gas fields of Alaska’s North Slope. The social, economic, and environmental dimensions of nuclear energy are just as important as its scientific and technical dimensions, and the general public has a duty to keep itself well-informed. As Albert Einstein remarked shortly after the end of WWII, "To the village square we must carry the facts of atomic energy; from there must come America's voice." In Alaska, that proverbial village square is along the Yukon River in Galena. Brian Yanity is a graduate student at UAA, activist and freelance writer. He resides in an undisclosed location in Southcentral Alaska, and can be reached at byanity@insurgent49.com. |
-
Columnists -
-
also by this
writer -
Going Nuclear, part one A Sea of Potential A Letter to Mayor Begich On Renewable Energy In Anchorage Coal: Alaska's Other Black Gold, Part2 Coal: Alaska's Other Black Gold, Part 1 A Letter To BP From a Concerned Alaskan White Gold A Town Without Cars The Myth Of Outside Balto and Togo The Alaska Gas Pipeline: A Critical Analysis, Part Two The Alaska Gas Pipeline: A Critical Analysis, Part One Dispatches From New York City Alaska's Radical Labor History: 1905-1920 Anchorage In the Year 2030 All Aboard City Assembly Resists Change, Democracy Public Power: An Alaskan Tradition Alaska Oil and the Middle East A Fuel tax To Fund People Mover Interview With Rich Seifert Dear Mayor Begich ... Another Alaska Is Possible Avoiding Left Wing Cliches Remember The Knik Arm Ferry? A Million Trips A Day The Rest Of America Upside Down World Alaskan In Palestine North To The Future Ten Reasons To Stop The Knik Arm Bridge Missing The Bus Interview With Evon Peter |
|||||||
| Copyright
2005
Insurgent Media. All Rights
Reserved. in-sur-gent (in sur'jent), n. 1. a member of a group which revolts against the policies of its leadership. |
||||||||
