Nuclear energy is derived from splitting atoms (fission). In order for fission to occur, a small uncharged particle (neutron) must collide with a large, unstable atom, such as Uranium. The atom will then break apart, releasing heat energy and additional neutrons. The neutrons go on to split other atoms, while the heat is used to produce electricity in the following process:
- The heat is transferred to water (the exact process depends on the nuclear plant design).
- The water heats up until it produces steam.
- The steam power is used to turn turbines.
- The turbines power a generator, which produces electricity.
The Pros of Nuclear Energy
- It does not emit greenhouse gases
- It can be used to produce a great amount of energy
According to John McCarthy, in an internet article titled “Frequently Asked Questions About Energy,” which is located on Stanford's website, Uranium fission produces 10 million times the energy that is produced by burning coal. In the book The Pros and Cons of Nuclear Power (Rosen Publishing Group: 2008), Ewan McLeish explains that the energy released by one atom split is quite small; however, since atoms are so small, the reaction can be multiplied by millions or billions. Thus, a little energy adds up to a lot.
Atom splitting, thus, has the potential of producing a great amount of power. In fact, in its early stages, the future looked very bright for nuclear power. Lewis Strauss of the Atomic Energy Commission was quoted as predicting that nuclear power would be so readily available that electricity would be relatively free to future generations. Unfortunately, this scale of production did not occur. The downfalls of nuclear power soon halted its promising growth.
The Cons of Nuclear Energy
There are six main arguments against using nuclear power, though each one can be debated.
- Expense: Mining and processing uranium is costly, as is the building and operation of the power plants.
- Waste: Though nuclear fission does not release harmful gases, it does produce harmful waste products. This radioactive waste must be stored for as many as a thousand years before it is safe.
- Accidents: It is debatable that the risk of a nuclear accident is less than or equal to that of other fuel productions. Yet, two nuclear accidents continue to cause many people to fear nuclear power: 1) the partial meltdown at Three Mile Island in 1979 2) the devastating Chernobyl explosion in 1986 and the resulting contamination of over 750,000 square miles of land surrounding the plant. The fact that these incidents were most likely caused in part by, respectively, poor procedures and poor plant design, they highlight the factor that human error plays in the dangers of nuclear power.
- War and Terrorism: The plutonium produced in uranium fission can be used to make devastating bombs, like the ones dropped in 1945, which killed over 100,000 people. As well, the plants themselves could be targets for catastrophic terrorist attacks. However, many plants are specifically designed to control the possible damage associated with such an attack.
- Non-Renewable Resources: Uranium itself is a non-renewable resource. Though technology is available to dramatically reduce the amount needed for energy production, uranium can eventually be used up.
- Limited Energy Source: Nuclear power only produces electricity. Thus, it cannot solve all of our energy needs alone.
Applications of Nuclear Energy
The most important application of nuclear energy is for electricity generation in thermonuclear plants. Thermonuclear power plants exploit the immense energy released during nuclear fission chain reaction. The chain reaction is controlled within reactors of thermonuclear power plants so that it proceeds at an appropriate speed for converting the heat given off during reaction to generate steam. The steam generated runs the turbine which in turns propels the electric generator.
If the nuclear fission chain reaction is left uncontrolled, it can release enormous amounts of energy resulting in nuclear explosion. This is the principle forming the basis of nuclear weapons such as an atomic bomb.
Environmental Aspects of Nuclear Energy
The major environmental advantage of nuclear energy is its lack of greenhouse gas emissions. Nuclear Power in a Warming World by Lisbeth Gronlund et al. and published by the Union of Concerned Scientists (UCS) in December 2007 states “Nuclear power plants do not produce global warming emissions when they operate, and the emissions associated with the nuclear fuel cycle and plant construction are quite modest. Thus an expansion of nuclear power could help curb global warming.”
The major environmental danger of nuclear energy is the threat of radioactive wastes. “Nuclear Power: Undermining Climate Protection”, published by Greenpeace International in October 2008 states “There is no safe solution to dealing with the dangerous radioactive waste produced by nuclear power. An average nuclear reactor produces 20-30 tonnes of highly radioactive spent fuel each year, which remains radioactive for hundreds of thousands of years”.
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