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Nuclear Energy. About 20% of US electricity is from nuclear power plants. [http://www.nrc.gov/images/info-finder/reactor/reactors-map.gif]. Nuclear Energy. A nuclear reactor uses heat from a controlled fission reaction This is used to create the steam needed to generate electricity.
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Nuclear Energy • About 20% of US electricity is from nuclear power plants.
[http://www.nrc.gov/images/info-finder/reactor/reactors-map.gif][http://www.nrc.gov/images/info-finder/reactor/reactors-map.gif]
Nuclear Energy • A nuclear reactor uses heat from a controlled fission reaction • This is used to create the steam needed to generate electricity. [http://www.converdyn.com/industry/images/chain-reaction.gif]
Nuclear Energy • Control Rods are used in the core to make sure the fission reaction does not create too much heat. • Made from Boron or Cadmium Click Here for a Demo. [http://www.pplweb.com/NR/rdonlyres/2FD20393-1529-462D-BF8D-266B8B3AC063/0/diagram_controlrod.gif]
The core of a reactor. Cerenkov radiation [http://echelon1.mit.edu/~nate/reactor/cerenkov.jpg]
[http://www.johnharveyphoto.com/RoadTrip/NuclearReactor.jpg] Cooling Tower, not the reactor!
[http://www.eia.doe.gov/cneaf/nuclear/page/at_a_glance/states/tn_chattanooga%20.jpg][http://www.eia.doe.gov/cneaf/nuclear/page/at_a_glance/states/tn_chattanooga%20.jpg]
Nuclear Energy • Nuclear fuel is Uranium Dioxide (UO2) • 3-5% of U-235 isotope must be present. • Remember: U-238 is most abundant! (only 0.7% is U-235) [http://americanhistory.si.edu/tmi/images/02.09_thumb.jpg]
Uranium Soil Concentrations [http://upload.wikimedia.org/wikipedia/en/1/12/Uraniumdisstribution.jpg]
Nuclear Energy • Pros • No air pollutants. • No carbon dioxide. • Overall efficiency around 35%, same as fossil fuel plants. • Only $0.03 per kWh of energy produced (but larger “start-up” costs)
Nuclear Energy • Cons • Mining for uranium. • Disposal of nuclear waste. • Possible release of radioactivity. • RBMK Reactor (Chernobyl) vs. LWR Reactor (United States) [http://www.nrc.gov/waste/spent-fuel-storage/spent-fuel-stor-locations.gif]
RBMK Reactor (Chernobyl) If H2O is lost, reaction speeds up!
LWR Reactor (United States) [http://casenergy.org/wp-content/uploads/2009/09/student-bwr.gif] If H2O is lost, reaction slows down!