George

George
 * Essay: **

**Introduction:**
Nuclear energy is the most powerful source of energy known to man. Uranium is found in the Earth's crust about as commonly as tin (2.8 //ppm U// on average in the Earth's continental crust). Nuclear energy is a very efficient source of energy (the energy generated by 1//kg// of 100% pure Uranium 235 is equivalent to 1,500,000//kg// (1500//t//) of coal). Also, nuclear fission does not produce any greenhouse gases, therefore nuclear energy would be a powerful and practical replacement to fossil fuels.

**Nuclear Energy Generation:**
There are two sets of circumstances in which nuclear energy can be produced, one such situation is inside the extreme heat at the core of the sun were the massive heat and pressure force **deuterium** (1 Proton, 1 Neutron) and **tritium**(1 Proton, 2 Neutrons) together with such force that they fuse together creating an unstable isotope of the element Helium (Helium 5 (2 Protons 3 Neutrons). Therefore, the helium atom must jettison one of its neutrons to stabilize and in doing so releases a large amount of energy. This energy is given off as the heat and light that the sun sends through space to the rest of the universe. This process is called **fusion** and in the future could be used as a safe, effective and sustainable means of generating all the electricity humanity needs. The other method of producing nuclear energy is through a process known as **nuclear fission**. Nuclear fission takes place when a free neutron traveling at high speeds impacts the nucleus of a heavy atom such as Uranium 235 (92 Protons 235 Neutrons) or Plutonium 239(94 Protons 239 Neutrons) that is stored in a fuel rod submerged in water that is pressurized to keep it from evaporating causing the impacted atom to break apart and release tremendous amounts of energy in the form of heat as well as more neutrons which impact other nuclei in a repetitive pattern called a **chain reaction**. The pressurized water flows out of the core and boils unpressurized water which turns to steam and powers a turbine connected to a generator which creates electricity.

**Advantages of Nuclear Energy:**
Nuclear energy has many advantages, for example, Uranium 235 generates 1.5 million times more energy than coal. Also, nuclear power plants do not produce any greenhouse gases through nuclear reactions and therefore do not contribute to global warming unlike power stations that run on fossil fuels. Surprisingly, since nuclear weapons are the most powerful weapons ever created, they seem to have a significant stabilizing effect on global politics because the damage inflicted by these weapons makes the cost/casualties of any military conflict unacceptable.

**Disadvantages of Nuclear Energy:**
Although nuclear energy can be very advantageous to humanity, it can also be very hazardous to our world, for example, the nuclear waste produced by nuclear fission is highly radioactive and can remain so for thousands of years. Also, this waste needs to be stored in special containers and either buried deep inside a mountain or submerged in a lake or cooling pool. Another disadvantage of nuclear energy is that radioactive fallout from the aftermath of a nuclear weapon's use or from a damaged nuclear reactor could spread over huge areas making large areas uninhabitable by humans, plants and animals for long periods of time.

**Questions: ** **1. How nuclear energy is used to solve energy scarcity? **Nuclear energy is:
 * Plentiful Eg. Uranium found in the Earth's crust is about as plentiful as tin (2.8 //ppm U// on average in the Earth's continental crust)
 * Efficient because it generates so much power with comparatively little waste Eg. The energy generated by 1//kg// of Uranium 235 is equivalent to 1,500,000//kg// (1500//t//) of coal


 * 2. How is nuclear energy produced? **
 * Nuclear Fission
 * Fast moving neutron collides with a uranium or plutonium atom
 * Nucleus breaks apart into two smaller nuclei releasing several neutrons in the process along with highly radioactive gamma-rays that requires one foot of solid lead or 6 feet of concrete to absorb. (Source: The Chicago Museum of Science and Industry)
 * The new neutrons go on to break more nuclei in a chain reaction that produces immense heat and intense radiation.
 * The heat generated by nuclear fission is radiated onto pressurized water (the water is pressurized to keep it from evaporating).
 * The pressurized water carries the heat from the fuel rods, (metal tubes filled with uranium dioxide pellets), to a steam generator.
 * Here the pressurized water uses the heat to boil unpressurized water, creating massive amounts of steam which is then piped to generators that generate electricity.


 * 3. What are the advantages and limitations of nuclear energy **
 * Advantages:**
 * Nuclear fission generates massive amounts of energy very efficiently (Uranium 235 generates 1.5 million times more energy than coal)


 * Disadvantages:**
 * Nuclear waste is created through nuclear fission and remains dangerously radioactive for long periods of time


 * Nuclear energy as a source of energy ||
 * Advantages || Disadvantages || Limitations ||
 * **Generates massive amounts of energy** || **Nuclear plants create radioactive waste** || **Nuclear plants have limited working lives and can be very expensive to replace** ||
 * * 1//kg// Uranium 235 generates 1.5 million times more energy than 1//kg// of coal
 * Is renewable up to a certain extent || * Nuclear waste remains dangerously radioactive for 4.5 billion years || * On average, a nuclear power plant has a "working life" of 50 years
 * Building a nuclear power plant can cost up to 2 billion US dollars (not including fuel and maintenance costs) ||
 * **Nuclear power is carbon neutral** || **Nuclear waste can be weaponized** || **Availability of nuclear fuel** ||
 * * Nuclear power plants do not create greenhouse gases and therefore do not contribute to global warming || * Terrorists can turn nuclear waste into weapons which would give them a huge leverage point on which to make governments do whatever they want. || * At current consumption, 'proven' sources of uranium will only last 30-60 years
 * Many sources of nuclear fuel, such as sandstone and seawater are unusable because it would be too expensive to refine. ||
 * || **Nuclear disasters** ||  ||
 * || * If a nuclear power plant is damaged, has a meltdown, etc... large amounts of radiation/radioactive materials can escape into the air/water and contaminate huge areas ||  ||

624 mph(1,005 km/h) || Mutually Assured Destruction (M.A.D.) is where if one country uses a nuclear weapon on another country that also has nuclear weapons, country #2 will use their weapons on country #1 and the conflict would escalate until both countries are obliterated and the radiation released would make living on the earth's surface impossible. || In Hiroshima, 70,000 people were killed instantly by the blast when "Little Boy" detonated and destroyed 69% of the buildings in Hiroshima ||
 * Nuclear energy as a weapon ||
 * <span style="background-color: transparent; color: #000000; display: block; font-family: Arial; font-size: 16px; text-align: center; text-decoration: none; vertical-align: baseline;">Advantages || <span style="background-color: transparent; color: #000000; display: block; font-family: Arial; font-size: 16px; text-align: center; text-decoration: none; vertical-align: baseline;">Disadvantages || <span style="background-color: transparent; color: #000000; display: block; font-family: Arial; font-size: 16px; text-align: center; text-decoration: none; vertical-align: baseline;">Limitations ||
 * **Very Powerful** || **M.A.D.** || **Indiscriminately destroys everything** ||
 * The "Fat Man" A-bomb exploded with the force of 21 kilotons of TNT generating temperatures of 7,050 °F (3,900 °C) and wind speeds of up to
 * **War Deterrent** || **Nuclear Fallout** ||  ||
 * Being the most powerful weapon ever created results in a significant stabilizing effect on global politics because the damage inflicted by these weapons makes the cost/casualties of any military conflict unacceptable. || After the detonation of a nuclear weapon, unfissioned "fuel", particles vaporized by the detonation of the weapon and dust particles charged with radiation are sucked up into the atmosphere and spread across huge areas. ||  ||


 * <span style="background-color: transparent; font-family: Arial; font-size: 15px; text-decoration: none; vertical-align: baseline;">4. How does nuclear radiation affect the environment? **
 * Pollutes the air and water
 * Damages plant / animal / human cells causing cancer or other diseases
 * Heats up marine environments reducing the amount of oxygen in the water


 * <span style="background-color: transparent; font-family: Arial; font-size: 15px; text-decoration: none; vertical-align: baseline;">5. How does nuclear radiation affect health? **
 * Damages cells causing cancer or other diseases
 * Indirectly: if we eat meat / fruits / vegetables that have been contaminated by radiation, the radiation given off by the food can seriously damage organs such as the:
 * stomach
 * Intestines
 * blood vessels

http://www.cameco.com/uranium_101/uranium_science/uranium/
 * Url List:**

http://wiki.answers.com/Q/How_many_pounds_of_coal_do_you_have_to_burn_to_equal_the_potential_energy_of_one_pellet_of_uranium

http://www.energyandcapital.com/articles/nuclear+energy-investing-uranium/402

http://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki

http://www.fas.org/nuke/guide/usa/doctrine/doe/younger.htm