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Nuclear power

BACKGROUND

In 1932, physicists John Cockcroft of England and Ernest Walton of Ireland were the first to split the atom with high-speed protons. This accomplishment led to their winning of the Nobel Prize in physics in 1951. Also in 1932, English physicist James Chadwick identified subatomic particles with neutral electrical charges, thus discovering the neutron.

Five years later, the Westinghouse Corporation constructed the Van de Graaff generator. The five-million-volt generator was used to collect and store electrostatic charges. The charge could be released in a single spark, which was equivalent to a bolt of lightning. The generator was used for atom splitting and other nuclear technology research.

In 1939, the U.S. Army began atomic energy research in Los Alamos, New Mexico. The goal of the top-secret program, known as the Manhattan Project and led by J. Robert Oppenheimer, was to develop the first transportable nuclear bomb.

In 1942, Enrico Fermi and colleagues at the University of Chicago were the first to control a nuclear chain reaction in a low-powered reactor beneath the stands of the university's stadium. The reactor used neutrons that were capable of splitting atoms, in order to release more neutrons to continue the chain reaction.

In 1945, the United States dropped atomic bombs on Hiroshima and Nagasaki in Japan, to force the Japanese Army to surrender and end World War II. Three years later, the United States announced plans to commercialize nuclear power in order to generate electricity.

Today, nuclear power generates about 20% of the country's electricity. According to the U.S. Department of Energy (DOE), it is the largest source of emission-free energy. Globally, there are more than 400 commercial nuclear power reactors operating in 30 countries. These reactors provide around 15% of the world's electricity. Aside from commercial nuclear reactors, there are about 250 research reactors in 56 countries worldwide.

U.S. lawmakers support nuclear power, claiming that it is a safe alternative energy source to foreign oil; as it does not produce air pollutants (such as sulfur or greenhouse gases) that are of high environmental concern.

Around 53% of the American oil supply is imported; one fourth of this supply comes from the Middle East. The U.S. DOE's Energy Information Administration (EIA) projects that our current use of fossil fuels could raise America's dependence on foreign oil to 65% by 2030.

Current U.S. legislation aims to curb dependence on foreign oil by investing $150 billion in clean energy research over the next ten years. The Obama administration has also implemented more aggressive efficiency standards for household appliances, as well as investing in alternative fuels for domestic automobiles.

No deaths have occurred due to the operation of a civilian nuclear power plant in the United States since 1954. In contrast, about 10,000 Americans die each year from the inhaled pollutants of burning coal.

In the United States, the nuclear power industry creates about 2,000 tons of radiation-emitting solid waste each year, composed primarily of unconverted uranium and transuranic actinides (plutonium and curium). In contrast, coal-fueled power plants in the United States release 100 million tons of ultrafine (less than 0.1©m in diameter) mercury and nitric oxide-containing particulates into the environment annually. Radioactive emissions from coal power plants are about 100 times greater than emissions from nuclear energy sites with comparable electrical outputs.

According to the U.S. Nuclear Energy Institute, there are 31 states with operating nuclear reactors. Palo Verde, Arizona, operates the largest U.S. nuclear power plant, generating over 3.2 gigawatts (GW) of electrical power a year, serving an estimated four million people.

Research indicates that the U.S. public has negative views towards nuclear power, with concerns regarding the accumulation of radioactive waste and the potential for core meltdowns, resulting in radioactive contamination. Public opinion, however, may be heavily influenced by biased or inadequate information sources.

The U.S. Nuclear Regulatory Commission (NRC) has implemented numerous changes to nuclear power plants over the past 30 years, in order to ensure that the facilities are safe and efficient. The NRC oversees accreditation, performs training inspections, and conducts site audits.

TECHNIQUE

Nuclear power plant: Nuclear power plants do not burn any fossil fuels. Instead, they produce energy by the splitting of uranium atoms in a process called nuclear fission. The process of nuclear fission allows us to produce electricity without releasing carbon dioxide into the atmosphere.

Uranium is a naturally-occurring element found in trace amounts in rocks, soil, and water. Though a small portion of uranium is supplied by domestic sources, over 85 percent of uranium used for nuclear energy in the United States is imported.

Nuclear fission: Nuclear power plants obtain the heat needed to produce steam through a physical process known as fission. In nuclear fission, a neutron hits a uranium atom, causing it to split. Splitting of the uranium atom releases large amounts of heat and radiation. Additional released neutrons are capable of splitting other uranium atoms, leading to a chain reaction.

Nuclear fuel: Nuclear fuel consists of two types of uranium: U-238 (the majority of nuclear fuel) and U-235. In nature, more than 99% of uranium is U-238 and about 0.7% exists as U-235. The two isotopes differ in their number of neutrons: U-238 contains 146 neutrons and U-235 has 143. The two isotopes also differ in half-life; the half-life of U-238 is 4.47 billion years and the half-life of U-235 is around 704 million years.

Uranium fuel consists of small, hard ceramic pellets packaged into 12-foot-long vertical tubes that are inserted into the reactor.

Nuclear reactors: The two types of nuclear power plants in the United States are boiling water reactors and pressurized water reactors. About two-thirds of the reactors in the United States are pressurized (70), while one-third (35) are boiling water reactors. Boiling water reactors heat the water that surrounds the nuclear fuel and turns that water directly into steam in the reactor vessel. Pressurized water reactors heat the water surrounding the nuclear fuel, but keep the water under pressure to prevent it from boiling.

In a boiling water reactor, hot water is pumped from the reactor vessel to a steam generator. There, heat from the water is transferred through a steam line to a second, separate supply of water. This water supply boils to make steam. The steam spins the turbine, which drives the electric generator to produce electricity.

THEORY/EVIDENCE

Nuclear energy history: The U.S. Congress created the Atomic Energy Commission (AEC) in 1946. The purpose was to promote the development of nuclear energy. The AEC authorized the creation of Experimental Breeder I (EBR I) in Idaho, which generated the first electricity from nuclear energy on December 20, 1951. The energy created was initially used to power four 200-watt light bulbs and eventually used to power the entire site. Though the experimental reactor was not used as a functional power plant, EBR-1 is a significant landmark in the development of nuclear power.

The nuclear power industry quickly expanded throughout the United States in the 1960s. However, the industry growth began to decline in the 1970s and 1980s due to concerns over reactor safety and waste disposal.

Policies: President George W. Bush established the National Energy Policy Development Group in 2001, which recommends expanding the role of nuclear energy as a major resource.

The Energy Policy Act, signed into law by President George W. Bush on August 8, 2005, supports the building of new nuclear power plants in the United States because of its efficient means of electricity production that avoid emitting greenhouse gasses. Additionally, the Act provides protection tax credits and loan guarantees to innovative technologies that promote the advancement of nuclear power.

Massachusetts Institute of Technology (MIT) study: In 2003, Massachusetts Institute of Technology (MIT) published research evaluating the future of nuclear power.

The MIT study analyzed the steps required to use nuclear power as an alternative option to reduce greenhouse gas emissions from current fossil fuel-burning power plants. The study concluded that the number of nuclear power plants must significantly increase in order to stop the production of greenhouse gas emissions of fossil fuel-burning power plants such as coal and oil.

The MIT research team surveyed 1,350 adults in the United States to determine their attitudes towards nuclear power. The researchers found that the U.S. public does not consider nuclear power to be the solution to global warming. According to the results of the MIT researchers, the U.S. public may be hesitant to support nuclear power program's increase of nuclear power plants without being informed of safety improvements and reduced development costs compared to nuclear energy sites of the past.

HEALTH IMPACT/SAFETY

U.S. Atomic Energy Commission (AED): The U.S. AEC was established in 1947 to oversee the development and control of nuclear science and technology. After World War II and the global display of nuclear power, the U.S. Government shifted the oversight of atomic energy to U.S. civilians, while security of nuclear facilities remained in the hands of the military.

The development of the AEC helped inspire post-war optimism, declaring that nuclear power was not only essential for national defense and maintenance of global peace, but also domestic energy production. The AEC helped ensure public safety from the hazards of nuclear power plants as the nuclear power industry rapidly developed. With this growth, the AEC began to receive criticism about inadequate regulation of radiation and environmental protection standards and site planning. Given the expansive growth of the industry, the AEC's responsibilities quickly outgrew their abilities, and the agency was terminated in 1974.

U.S. Nuclear Regulatory Commission (NRC): The NRC was created by Congress and signed into law by President Gerald Ford in 1974, with the purpose of taking over the AEC's growing list of responsibilities and regulating nuclear power sites.

The NRC has established standards to protect public health (for example, preventing equipment malfunctions, procedural accidents, and radiation leakage to the public). Additionally, the NRC is responsible for licensing and inspecting nuclear power plants in the United States to ensure they are in compliance with safety standards.

International Atomic Energy Agency (IAEA): In 1957, the "Atoms for Peace" organization was established to promote safety and security in atomic energy programs with an emphasis on their use for international peace. Now known as the IAEA, this agency has expanded its initial goal of safety and security to also include science and technology, and safeguards and verification. The IAEA has developed into a powerful political organization that has helped negotiate flexibility in research and funding in nuclear technologies. The IAEA works closely with the United Nations in promoting these technologies and emphasizing global collaboration and peace.

World Nuclear Association (WNA): In 2001, what was formerly known as the Uranium Institute (UI) broadened its member-base and became known as the WNA. The WNA is an international organization promoting the use and development of nuclear energy. Members of this organization are many of the companies that comprise the global nuclear power industry. Since 2001, the WNA has more than tripled in membership and includes nearly 90% of the companies that are involved with the handling of uranium, development of reactors, and nuclear engineering, construction, and waste management. Seeing the need for collaboration in clean energy production, the WNA has helped unify the global industry make advances for the future.

Three Mile Island accident: The Three Mile Island (TMI) nuclear power plant was located near Middletown, Pennsylvania. A serious U.S. commercial nuclear power plant accident occurred at TMI on March 28, 1979, but it did not result in any deaths or injuries to plant workers or residents of the nearby community.

The incident at TMI was a system failure consisting of power plant equipment malfunctions, design-related problems, and worker errors. All of these factors resulted in a severe core meltdown. A nuclear meltdown is a critical nuclear reactor incident that occurs from inadequate cooling of the reactor, due to improper use or equipment malfunction. In a nuclear meltdown, overheating of the reactor may result in damage to the core, allowing the uranium or plutonium to spill out. At temperatures that can cause damage to reactors, uranium or plutonium overheats and eventually melts. A nuclear meltdown is considered the most dangerous type of nuclear power accident, and many reactors are constructed inside containment buildings to prevent further damage from occurring. Containment buildings are made of 1.2-2.4 meter airtight, steel-reinforced concrete that surrounds the reactor, designed to safeguard nuclear power sites in the event of a meltdown.

During the TMI accident, the NRC instructed pregnant women and pre-school-age children within a five-mile radius of the nuclear power plant to leave the area. During a core meltdown, large amounts of radiation are typically released into the air and into the environment. Only small amounts of radiation incapable of environmental damage were released due to relatively small areas of damage to the core.

Regulatory changes: Since the TMI accident, the NRC has implemented numerous changes in nuclear power plant regulations: for example, the NRC operations center is currently staffed 24 hours a day to enhance emergency response systems.

In addition, at least two inspectors are assigned to each nuclear power plant to ensure that the facility adheres to the NRC's requirements on a daily basis.

Nine months after the accident, the Institute of Nuclear Power Operations in Atlanta was formed by the U.S. nuclear power industry. This agency implemented continuous improvement among nuclear power plant operators nationwide.

Chernobyl: In 1986, nuclear researchers in the Ukraine attempted unauthorized experiments using four pressurized-water reactors cause them to overheat, releasing the pressurized water as steam. Hydrogen formed from the steam caused two explosions and a fire damaging the site, releasing radioactive particles into the atmosphere that exposes most of Europe to dangerous levels of radiation.

In 2003, the United Nations Development Programme started the Chernobyl Recovery and Development Programme (CRDP) to assist the recovery of the areas affected by the meltdown. The program continues to work with the Ukraine government to rehabilitate the social, economic, and ecological aspects of the regions most heavily devastated from the Chernobyl catastrophe.

Environmental hazards: For safety and functional purposes, nuclear power plant sites must be constructed at areas with contact with water. Water is used to produce nuclear power and absorb thermal discharge in periods of reactor malfunction. At all nuclear power sites, thermal discharge directly affects the environment in the waters nearby. High-temperature waters nearby the plant encourage the growth of thermophilic bacteria and parasites capable of infecting organisms that are exposed.

It is also suggested that thermal effluents change reproductive behaviors of fish. Fish populations in areas surrounding nuclear power sites rapidly decline due to infection and low rates of reproduction. The reasons of this behavior are not completely understood.

Nuclear power plants can also emit high-energy radiation. When cells are exposed, radiation can cause mutation and death of the cell. Site inspections are routinely performed to gauge the amount of radiation that is emitted. Under normal circumstances, there is no direct effect on the surrounding ecosystems. However, nuclear energy always poses a risk of core failure, which could lead to dangerous releases of radiation into surrounding air and waters. Radiation can travel through these mediums and can affect areas hundreds of miles away from the original source. Inspection is imperative to keep such events from occurring.

Nuclear waste: In the United States, radioactive waste is currently disposed of at the site of production. According to the U.S. Nuclear Regulatory Commission (NRC), since July 1, 2008, institutions of 36 states have no place to dispose of some classes of low-level waste (LLW). A permanent storage site for high-level nuclear waste (HLW) does not yet exist in the United States. Underwater storage facilities are insufficient and additional aboveground dry containment units are needed for the increasing amounts of nuclear waste. Environmental agencies, such as the Sierra Club, along with the NRC, support the federal government taking responsibility for the permanent storage of HLW and making disposal facilities for LLW more available.

FUTURE RESEARCH OR APPLICATIONS

Nuclear power: The Nuclear Power 2010 Program was first implemented by the U.S. Secretary of Energy on February 14, 2002. This program is a joint collaboration between the U.S. Government and nuclear power industry to identify new sites for nuclear power plants and develop innovative technologies.

As of 2007, the nuclear power industry has spent about $4 billion to generate 15,000 jobs in the United States. According to the Nuclear Energy Institute, 17 companies have applied with the NRC to build 26 reactors.

Currently, two additional Advanced Boiling Water Reactors (AWBRs) are planned for construction at the South Texas Nuclear Generating Station, which will generate 2,700 MW of electricity, doubling its current capacity. Other prospective sites are Bell Bend, PA; Hollywood, AL; Galena, AK; Cherokee County, SC; Levy County, FL; and Victoria County, TX.

Nuclear fission: The U. S. National Aeronautical and Space Agency (NASA) is currently researching nuclear fission as a power resource for human outposts planning to be constructed on the moon. Utilizing nuclear power on the moon has the potential to produce the equivalent amount of electrical power for about eight average households on earth.

This groundbreaking research may produce nuclear reactors the size of trashcans that are able to produce 40 kilowatts of electricity, enough to power an entire human outpost on the moon. Technology testing is expected to occur in 2012 or 2013 to determine the safety and performance of this system.

AUTHOR INFORMATION

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

  • Ahn YH, Shanmugam P, Lee JH, et al. Application of satellite infrared data for mapping of thermal plume contamination in coastal ecosystem of Korea. Mar Environ Res. 2006 Mar;61(2):186-201. View abstract
  • Harris JT, Miller DW. Radiological effluents released by U.S. commercial nuclear power plants from 1995-2005. Health Phys. 2008 Dec;95(6):734-43. View abstract
  • International Atomic Energy Agency (IAEA). www.iaea.org
  • Ion S. Nuclear energy: current situation and prospects to 2020. Philos Transact A Math Phys Eng Sci. 2007;Apr 15;365(1853):935-44. View abstract
  • Khan RA, Hooper RG. Influence of a thermal discharge on parasites of a cold-water flatfish, Pleuronectes americanus, as a bioindicator of subtle environmental change. J Parasitol. 2007 Oct;93(5):1227-30. View abstract
  • Massachusetts Institute of Technology. www.web.mit.edu
  • National Aeronautical and Space Agency (NASA). www.nasa.gov
  • Natural Standard: The Authority on Integrative Medicine. www.naturalstandard.com
  • Nuclear Energy Institute. www.nei.org
  • Okrent D. The safety goals of the U.S. Nuclear Regulatory Commission. Science. 1987;Apr 17;236(4799):296-300. View abstract
  • Solovykh GN, Fabarisova LG, Nefedova EM, et al. Effect of thermal power stations on the sanitary and biological conditions of water reservoirs. Gig Sanit. 1998 Nov-Dec;(6):24-7. View abstract
  • U.S. Department of Energy (DOE). www.ne.doe.gov
  • U.S. Nuclear Regulatory Commission (NRC). www.nrc.gov
  • World Nuclear Association (WNA). www.world-nuclear.org


Copyright © 2011 Natural Standard (www.naturalstandard.com)
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