Chapter 3 - Types of nuclear reactors

Abstract

The successful demonstration of neutron fission in 1938 and the setting up of the first nuclear reactor in 1942 paved the way for harnessing power from the atom. Since then several hundreds of reactors catering to various applications have been built and operated. Most of the nuclear energy produced is based on the only natural fissile species 235U. Ninety percent of the world's nuclear reactors use light water as the coolant. However, there are several designs based on other coolants of low atomic mass such as heavy water, graphite, or carbon dioxide gas. The nuclear reactors can also be grouped with respect to the neutron energies or their operating pressure and temperature conditions. This chapter gives historical perspective of different types of nuclear reactors currently in operation and a brief introduction to their designs. Another basic source of energy is the fusion of light nuclei. While fission reactors are being discussed, it is also important to understand the concepts of accelerator-driven systems and fusion reactor design aspects. Subcritical systems are driven by accelerators and are another form of reactor design which can be effectively used for power production and incineration of nuclear waste. This chapter gives a brief compilation of some of these energy systems too.