by Bernard L.Cohen
Department of Physics
University of Pittsburgh
Since Energy sources derived from the sun are called "renewable," that adjective apparently means that they will be available in undiminished quantity at present costs for as long as the relationship between the sun and the Earth persists, about 5 billion years. It is the purpose of this note to show that breeder reactors using nuclear fission fulfill this definition of a renewable energy source, and in fact can supply the world's energy needs at the present costs for that time period.