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| Fig. 1:A table and pie graph showing world electricity consumption by source in 2016. [9] (Courtesy of British Petroleum) |
Humans use a multitude of sources to produce enough energy to meet the needs of the world. The primary source of energy, fossil fuels, has been long documented for releasing harmful products that negatively affect the global ecosystem. Fig. 1 displays the world electricity generation by source in 2016. Renewable energy sources, like solar power, hydroelectricity, and wind energy, have become more popular in this day and age, but there is another energy source that is used all around the world. In essence, nuclear energy is collected by injecting nuclear fuel with a neutron and capturing the energy emitted from the fission, or splitting of the atom. The result of this leads to radiation that has a documented negative effect on the health of human beings. [1]
Nuclear power plants generate waste as they produce energy. Nuclear waste is the material left over after the reaction previously mentioned. Although the fuel may look the same, the nuclear reactions cause drastic changes. The byproducts remaining in the fuel are known as fission products and they are the basis of high-level nuclear waste. [2] This used fuel is extremely radioactive and will continue to be for thousands of years. To prevent the radiation from escaping, it must be stored in secure conditions. [3] There are options for a final disposal but this process does not completely negate the releasing of radiation.
The paramount source of radiation in high-level nuclear waste are the β-decay of fission products and α- decay of actinide elements. [4] The β-decay of fission products is responsible for heat generation and the elevated temperatures early in the history of waste storage in which may last hundreds of years. The β and α-decay events can cause radiation damage through three processes in the formation of waste that are listed below: [3]
Elastic collisions between nuclear particles and the atoms in the host matrix which cause intense collision cascades and atomic displacements.
Ionization effects associated with the γ-rays, β-particles, and α-particles.
The transmutation of radioactive parent nuclei into different elements.
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| Fig. 2: An image displaying Yucca Mountain and its potential to act as a nuclear waste repository. (Source: Wikimedia Commons) |
This spent nuclear fuel must be contained and isolated from the environment for a long period of time. Generally, the fuel is kept underwater, in which acts as a thermo-shield. The water conducts away the heat that is emitted from the radioactive spent fuel rods. It remains this way until the radiation decays enough to be contained in concrete storage tanks. [3] There is a push to store this waste under Yucca Mountain, as shown in Fig. 2. With that said, spent nuclear fuel can be a valuable asset, not simply waste. Once nuclear fuel is used in the original reactor, it can be treated and used as fuel in another reactor. [5]
In conclusion, nuclear radiation causes problems within our environment and effective spent fuel storage is vital to mitigating those consequences. The risks do not outweigh the benefits of producing energy using nuclear reactions because nuclear waste must be stored away from the environment for tens to hundreds of years in cooling pools or dry-cask storage facilities. [6] Continuing to use nuclear energy will only exacerbate the issue of finding a final resting place for spent nuclear fuel. The products of these reactions are problematic and will continue to be dangerous, even if stored deep underground as proposed by the Yucca Mountain nuclear waste repository. [7] There was approximately 63,000 metric tonnes of nuclear waste in America as of 2014 and a subtle mishandling of this material could be catastrophic. [8] Roughly 40,000 of these metric tonnes are fated to be stored in the Yucca Mountain repository. [8] The fate of global energy production should not rely on a mechanism that inherently produces a highly dangerous byproduct; especially, a mechanism that must be stored in a perfect manner to reduce its harmful effect on people and the environment. Nuclear energy is not tomorrow's fuel source.
© Frank Buncom IV. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] H. Shimp, "Effects to the Human Body From Nuclear Fallout," Physics 241, Stanford University, Winter 17.
[2] R. C. Ewing, "Radiation Effects In Nuclear Waste Forms For High-Level Radioactive Waste," Prog. Nucl. Energy 29, 83 (1995).
[3] M. Bunn et al., "The Economics of Reprocessing versus Direct Disposal of Spent Nuclear Fuel," Nucl. Technol. 150, 209 (2007).
[4] M. Eisenbud and T. F. Gesell, Environmental Radioactivity, 4th Ed. (Academic Press, 1997).
[5] T. Inoue, "Actinide Recycling by Pyro-Process with Metal Fuel FBR for Future Nuclear Fuel Cycle System," Prog. Nucl. Energy 40, 547 (2002).
[6] R. C. Ewing, "Long-Term Storage of Spent Nuclear Fuel," Nat. Mater. 14, 252 (2015).
[7] J. Garcia, "The Yucca Mountain Nuclear Waste Repository," Physics 241, Stanford University, Winter 2012.
[8] J. C. S. Long and R. C. Ewing, "Yucca Mountain: Earth-Science Issues at a Geologic Repository for High-Level Nuclear Waste," Annu. Rev. Earth Pl. Sci. 32, 363 (2004).
[9] "BP Statistical Review of World Energy 2017," British Petroleum, June 2017.
