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Nuclear Fission. Hillary Call. Outline. Benefits of Nuclear Energy How Fission Works Nuclear Power Plant Basics Overview of Uranium Fuel Cycle Energy Lifecycle of Nuclear Power Generation IV Reactors Technical Challenges Conclusions. Benefits of Nuclear Energy.
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Nuclear Fission Hillary Call
Outline • Benefits of Nuclear Energy • How Fission Works • Nuclear Power Plant Basics • Overview of Uranium Fuel Cycle • Energy Lifecycle of Nuclear Power • Generation IV Reactors • Technical Challenges • Conclusions
Benefits of Nuclear Energy • Continuous, reliable supply of energy • Well-developed technology • 12,700 reactor-years of commercial experience • Accounts for ~16% of world electricity generation • Extensive fuel supply • Breeder reactors • Fissile materials other than Uranium
How Fission Works • Water or other moderator slows neutrons, thermalizing them • Thermal neutron collides with U-235 • Unstable nucleus splits in two • Energy and neutrons are released • Reaction repeats
Pressurized Water Reactor (PWR) A common type of Light Water Reactor (LWR) http://www.eas.asu.edu/~holbert/eee460/pwrdiag.gif
Uranium Fuel Cycle http://www.arevaresources.com/nuclear_energy/datagb/cycle/cyclerep.gif
Energy Lifecycle of Nuclear Power Based on 3090 MW Forsmark plant operating for 40 years. http://nuclearinfo.net/Nuclearpower/TheScienceOfNuclearPower
Challenges • Radioactive waste storage/disposal • Yucca Mountain • Reprocess spent fuel • Safety • Only fatalities from commercial nuclear power plant occurred at Chernobyl • Must overcome public fear
Generation IV Reactors http://www.world-nuclear.org/info/inf77.html * high = 7-15 Mpa+ = with some U-235 or Pu-239** 'battery' model with long cassette core life (15-20 yr) or replaceable reactor module
Fast Breeder Reactors • U-238 captures a neutron and transmutes to Pu-239 • Pu-239 is fissile like U-235 • Increases efficiency of uranium use >50x • Could use up depleted uranium stockpiles & plutonium from dismantled weapons http://www.atomeromu.hu/mukodes/tipusok/gyorsreak-e.htm
Fast Breeder Reactors • 290 reactor-years of commercial experience • Monju (Japan) and Superphenix (France) • Not economically practical • More costly to construct • More difficult to operate • Proliferation dangers associated with plutonium
Conclusions • Nuclear fission is a viable energy source • It cuts down on CO2 emissions, improving air quality • New designs have made nuclear power safer and more economically feasible • Issue of radioactive waste will need to be addressed