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Page 1: Nuclear Energy and Nuclear Waste

Nuclear Energy and Nuclear WasteThe Good, The Bad, and the Ugly…

Page 2: Nuclear Energy and Nuclear Waste

What is Nuclear Energy?• Nuclear energy is the energy that exists within the

nucleus of an atom.• There are 2 types of Nuclear Energy:

•Nuclear fission is the splitting of a large nucleus, releasing HUGE amounts of energy.

•Nuclear fusion is the combining of smaller nuclei to form heavier nuclei, releasing HUGE amounts of energy.

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How is Nuclear Fission Energy produced?

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If a Nuclear Reaction is not controlled…

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Nuclear Energy must be harnessed if used to make energy.

• Nuclear reactions in a nuclear power plant occur at a controlled, manageable pace and release energy slowly.

• Heat is generated and used to boil water, creating steam. The steam turns turbines which rotate electric generators, creating electricity.

• Steam is released from the cooling towers.

• (click on picture for more info)

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How does a Nuclear Power Plant Work?

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How much energy is produced?

• Nuclear power is an extremely rich energy source.

• One gram of Uranium-235 delivers as much energy as 3.5 metric tons of coal!!!

• One in every 5 houses in the U.S. is supplied with nuclear energy.

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Where are Nuclear Power Plants located?

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Pros for Nuclear Power• Rich energy source.• 1 gram of Uranium-235 delivers as much

energy as 3.5 metric tons of coal.• Reactors run for years without refueling or being

shut down and need little maintenance.• No air pollution!

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Cons about Nuclear Power

• Produces Radioactive Waste• There is no permanent long-

term disposal site for commercial nuclear waste.

• There is a relatively short supply of 235U (only enough left for 100~200 years)

• Nuclear Power Plants are expensive to build.

• Minor maintenance problems can be very expensive to fix.

• Safety concerns!!!

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A Close Call at Home!!!

• The most serious nuclear accident in the U.S. occurred in 1979 at Three Mile Island nuclear power plant in Pennsylvania.

• A small amount of radioactive gas escaped the containment structure.

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Nuclear Waste• Plutonium, cesium, strontium, and other “-

ium” elements created in a nuclear reactor emit dangerous radiation that can literally knock electrons off the atoms of our cells, disrupting or destroying cell function or even causing cells to mutate into cancer cells.

• Radioactive elements emit radiation because they are unstable; they’d rather be something else.

• They achieve this by going to pieces; emitting particles and waves billions of times per second. This process is called a half-life.

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What is a Half-Life?

• Every radioactive element has a half-life

• Half-life is the time it takes for half of its atoms to decay.

• Half-lives range from a fraction of a second to billions of years – 4.5 billion for uranium 238.

• The longer the half-life, the less intense the radiation.

• After 10 half-lives, an element is usually harmless

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Types of Waste

Transuranic Waste– Includes clothing,

tools, and other materials contaminated with plutonium, neptunium, and other man-made elements heavier than uranium. (11.3 million cubic feet)

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Types of Waste• Low and Mixed Low-Level Waste

– Includes radioactive and hazardous wastes from hospitals, research institutions, and decommissioned power plants (472 million cubic feet)

– Turkey Point produced annually on average about 2,500 cubic feet of low-level waste. This amount of waste could be contained within an area about the size of a 30'x30' room.

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Uranium Mill Tailings•Residues left from the extraction of uranium ore (265 million tons).

Types of Waste