Electrical Engineering Professor Frank Chen has spent most of his life working with plasmas in a way that, he hopes, could solve the world's energy problems. By about the middle of the next century, Chen and others suggest, the world will face a critical energy shortage. Even at current usage rates, the world's oil and natural gas supplies will be exhausted in about one hundred years. Although coal reserves and nuclear power could continue to supply energy for several centuries, concerns about environmental problems caused by these sources make them undesirable. For more than 40 years, Chen has been among those examining fusion as a possible source of future energy.
Nuclear fusion is the benign twin of nuclear fission.
In a fission reaction, the nuclei of heavy atoms such as uranium are separated, releasing enormous amounts of energy. However, nuclear energy can also be released when two light nuclei join to form a heavier one. In the typical fusion reaction, the nuclei in the reacting gases are positively charged, and the natural repulsion between them must be overcome before they can join. To produce fusion energy, two hurdles need to be overcome. First, it is difficult to hold enough gas at this temperature for a long enough time to release more energy than it took to heat it, because the plasma would melt its container walls and cool very rapidly.