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Right after WWII, nuclear technology was perceived to offer a future of cheap, plentiful energy that would replace increasingly scarce fossil fuels. In hope for the transition of nuclear power from wartime to peaceful uses, the general public and even environmentalists embraced this technology, as they foresaw a major reduction in air pollution and reduced strip mining. Nuclear plants do not generate harmful emissions often associated with burning fossil fuels (See Chapter 8), and there appear to be no significant adverse effects to water, land, habitat, species, and air resources.

With the passing decades, however, reservations about nuclear energy began to grow as greater attention was focused on the issues of nuclear safety, weapons proliferation, high construction costs, and problems associated with waste disposal took away much of the glory of nuclear plants. At the start of the twenty-first century, some European countries began to reduce their dependence on nuclear energy. Currently, the US is generating only 20% of its electricity needs by nuclear power; this share is expected to decline even further, as there have been no new orders for nuclear plants since 1978. Except for in Asia, where new nuclear power plants are still being constructed, the growth for nuclear power is expected to be limited.

Fortunately, as demand for nuclear fission reduces, a new technology called “fusion” is rekindling an interest in nuclear energy. Fusion is the same process that powers our sun (Figure 11-20). The enormous amount of energy released by the sun in the form of radiation is a result of the conversion of some of its mass to energy, as predicted by Einstein’s equation E = mc2. Unlike in fission reactions, atoms are not split apart, but instead are fused together, hence the name nuclear fusion. In the case of our sun (and all other stars), massive gravitational forces compress and heat deuterium and tritium gases to form plasma. Plasma is sometimes referred to as the fourth state of matter (Figure 11-21) and is formed when gases are heated to a temperature that is high enough to cause ionization. This process knocks electrons out of the atom, causing it to be left with a positive charge. As the plasma is heated further, eventually a point will be reached where the positively charged atomic nuclei overcome their mutual electrostatic (Coulomb) repulsion and fuse together. In the process, helium, neutrons, and a tremendous amount of energy are produced. Researchers inspired by such reactions are working feverishly to replicate these processes on earth. If successful, fusion reactors have the potential of providing unlimited energy with fewer disadvantages than fission reactors.


(1) Toossi Reza, "Energy and the Environment:Sources, technologies, and impacts", Verve Publishers, 2005

Further Reading

Bodansky, Nuclear Energy Principles, Practices, and Prospects, Second Ed., Springer, 2004.

Seaborg, G., T., Peaceful Uses of Nuclear Energy, University Press of the Pacific, 2005.

International Journal of Nuclear Engineering and Design, Direct Science Elsevier Publishing Company, devoted to the Thermal, Mechanical, Material and Structural Aspects of Nuclear Fission.

Journal of Fusion Energy, Springer Netherlands. It features articles pertinent to development of thermonuclear fusion.

External Links

Federation of American Scientists (http://www.fas.org/nuke/intro/nuke/index.html).

International Atomic Energy Agency (http://www.iaea.org).

DoE Office of Nuclear Energy, Science & Technology (http://www.ne.doe.gov).

American Nuclear Society, (http://www.ans.org).

World Association of Nuclear Operator (WANO) (http://www.wano.org.uk).