CHAPTER 12 - The Fusion Programme

Abstract

This chapter discusses the fusion program. Just as certain heavy elements undergo exothermic fission, the fusing of light elements can be accompanied by the emission of energy. One of the most promising reactions is the fusion of the heavy isotopes of hydrogen and deuterium, which produces either the still heavier isotope of hydrogen, tritium, plus a proton or the light isotope of helium. In each case, the evolution of energy is considerable, approximately one part in a thousand of the total mass involved in the reaction being converted into energy. The products of fusion processes of deuterium with tritium are 23He , 13He , and 24He , and of these, the two helium isotopes are stable and therefore do not represent a possible radiation hazard. Tritium is radioactive but cannot be regarded as a waste product because it undergoes fusion more efficiently than does naturally occurring deuterium. Any fusion reactor would therefore be designed to recover the tritium produced for economic reasons, and with this, any health hazard represented by 3He would be considerably reduced. The total amount of radioactive material in a working fusion reactor is likely to be much less than that in a fission reactor.