Nuclear Energy

Conventional Nuclear power is done by a nuclear fission reaction (neutrons split the nuclei of atoms)

Light Water Reactors (LWR – produce 100% of the nuclear power in the U.S.

Fuel is Uranium oxide – 97 % is nonfissionable U238

3% is fissionable U235

moderator – neutron absorbing material to slow down the neutron emitted (graphite control rods)

Coolant – water that circulates through the core to remove heat

Containment vessel – steel reinforced concrete sea in the reactor

  • reactors are refueled once a year and fuel rods (which are still radioactive) are removed and stored in water-filled pools or dry cases
  • the long term goal is to store them underground
  • nuclear energy is very expensive due to overlapping safety features that reduce chance of a serious accident
  • * reactors are decommissioned after about 15 – 60 years
  • each step of the process (mining, processing, electricity production, storage, take down) add cost to using nuclear energy

U.S. started developing nuclear power in the late 50’s for three reasons

1)

2)

3)

  • It was projected that 1,800 plantswould supply 21% of the world’s power by the year 2000.
  • IN 2003there were 443 reactors in 30 countries producing only 6% of the world’s energy and 17% of its electricity
  • It is projected that U.S. production will drop form 17% in 2005 to 12% by 2025 due to aging plants
  • No new nuclear plants have been approved in this country since 1973. Why?

What are other countries doing about nuclear power?

What happened at Chernobyl? Why id this happen? How and how many people were affected? What are the estimates by Greenpeace? How does is it affecting the people of the Ukraine today?

What has France done in response to Chernobyl?

What are the trade offs (pros and cons) of conventional nuclear fuel

  • The U.S. Nuclear Regulatory Commission (NRC) estimates there is a 15 – 45% chance of a complete core meltdown at a U.S. reactor during the next 20 years
  • The NRC also found that 39 U.S. reactors have an 80% chance of containment shell failure from a meltdown or an explosion of gases inside the structure

What types of occurrences have occurred in the U.S in the past 10 years?

After reading about terrorist attacks and dirty bombs (pgs 377 and 378) do you think our nuclear facilities are safe from terrorist attacks? Support your answer

What are some proposed methods and possible drawbacks of disposing radioactive

wastes?

At least 228 large commercial reactors worldwide are scheduled for retirement by 2012. Half of the current reactors in the U.S. have applied to the NRC to extend their soon to expire 40 year license.

Describe three new types of Nuclear Reactors. Briefly explain how they work and also list the concerns associated with each.

Nuclear fusion is when two isotopes of hydrogen (deuterium and tritium) are combined at extremely high temperature (100 million degrees) to form a heavier helium nucleus. A controlled fusion reaction could produce almost a limitless source of energy and no radioactive material is used

Why are we not using it?