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Alternative energy: nuclear. Group 4 Bar Shida Keane. C ontent. Introduction Advantages Disadvantages Case Study Video Bibliography. Introduction. A nuclear power plant’s main source of energy is the radioactive uranium rods. Generate a lot of heat,
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Alternative energy:nuclear Group 4 Bar Shida Keane
Content • Introduction • Advantages • Disadvantages • Case Study • Video • Bibliography
Introduction • A nuclear power plant’s main source of energy is the radioactive uranium rods. • Generate a lot of heat, • When lots of water is poured on top of then, the water turns into steam, rises, and turns turbines placed on top of the uranium rods. • These rotating turbines generate electricity through a generator.
Advantages • Doesn’t depend on fossil fuels, isn’t affected by gas and oil prices • Nuclear energy does not emit carbon dioxide, which worsens global warming. • In fact, a properly functioning produces less radiation than a coal-based power plant • Nuclear fission produces roughly 1000000 times more energy per unit weight than fossil fuels.
Disadvantages • During transportation of nuclear materials, there is a risk of contamination • On average, a nuclear power plant generates 20 tons of nuclear waste every year, which emit radiation which can be lethal to life forms. • Properly storing the waste needs a lot of money, added to the high original cost of the nuclear power plant.
Case study • In March 2011, the Fukushima disaster—in which a massive earthquake sparked a tsunami that damaged the nuclear power plant—resulted in the largest ever discharge of radioactivity into the ocean. Levels of caesium-137 have remained at high levels compared to natural background levels. • Economic consequences for the area’s fishermen-lost an estimated $1.3–$2.6 billion as a result of fisheries closures. • The fish at the bottom layer of the food chain were also contaminated, sparking worries for seafood from area near Japan.
Case study • Radiation dose at the boundary of the Fukushima Daiichi nuclear power station on March 16: 1.9 millisieverts (mSv) per hour • Peak radiation dose measured inside Fukushima Daiichi on March 15:400 mSv per hour • Average exposure of U.S. residents from natural and man-made radiation sources: 6.2 mSv per year • Half-life of iodine 131, a dangerous radioactive isotope released in nuclear accidents: eight days • Half-life of cesium 137, another major radionuclide released in nuclear accidents: 30 years • Approximate amount of nuclear fuel in each crippled Fukushima Daiichi reactor: 70 to 100 metric tons
Case study • On April 6, the radiation level in the city of Fukushima was 13.9 μSv/h. If we multiply that number by the number of hours in a year, the yearly radiation dose is about 122,000 μSv. This number is more concerning. Remember, the U.S. does not allow workers to receive more than 50,000 μSv per year at work. • We do know that several Fukushima staff members and firefighters have been exposed to dangerous levels of radiation. At least six staffers were exposed to radiation levels greater than 100,000 μSv. • The level of radiation detected at the Fukushima plant immediately after the third explosion was extraordinarily dangerous for humans. Like Chernobyl, it is likely that an exclusionary zone will be created around the plant, and that some residents who lived nearby will never return home.
Video • Nuclear disaster at Fukushima http://www.youtube.com/watch?v=6Cy-PHxt2u8 Japan is preparing to mark the first anniversary of the huge earthquake and tsunami that devastated the northeast coast on March 11, sparking a nuclear crisis at the Fukushima Daiichi plant.
Bibliography • http://www.howstuffworks.com/nuclear-power4.htm • http://www.blacksmithinstitute.org/blog/?p=511 • http://www.the-scientist.com/?articles.view/articleNo/33275/title/Radiation-Still-High-Around-Fukushima/ • http://www.scientificamerican.com/article.cfm?id=japan-nuclear-fallout