NUCLEAR ENERGY (FUSION)
We have seen there is a proven technology ready to supply a substantial portion of our energy needs--nuclear fission. There are, as previously noted, objections to increasing our dependence on this source, some valid, some invalid. Fission reactors do produce long- lived dangerously radioactive byproducts that are difficult to store, and fission reactors do require active safety systems which could fail in operation. They also produce bomb material, plutonium, which requires stringent security measures to prevent this dangerous material from falling into unauthorized hands. The potential for accidents, despite the safety systems, does prey on people's imagination so the fission technology is not readily acceptable to many communities. Finally, the uranium used in fission reactors, while not in short supply, is not a renewable source and is not that plentiful, if we foreclose the possibility of converting it to plutonium.
There is a possibility, however, of producing nuclear energy without having any of these drawbacks. The sun produces its vast amount of energy by combining four nuclei of hydrogen to form a helium nucleus and two positrons, a process called fusion. The mass of the helium nucleus and the two positrons is less than the four hydrogen nuclei. The excess mass available in this reaction is converted into energy, according to the Einstein formula. We are ascending in this reaction the Curve of Binding Energy (Fig. 7.3). As already noted, this conversion is so generous in energy production that one