Fusion Energy

Abstract

Abstract As far as is known, nuclear fusion is the primary source of energy in the universe. It occurs when the nuclei of lighter elements, such as hydrogen, are fused together at extremely high temperatures and pressure to form heavier elements, such as helium. Whereas practical methods for harnessing fusion reactions and realizing the potential of this energy source have been sought since the 1950s, achieving the benefits of power from fusion has proved to be a difficult, long‐term challenge. Fusion is widely held to be the ultimate resource for the world's long‐term energy needs. The fuel reserves for fusion are virtually limitless and available to all countries. Fusion fuels can be extracted from water. Fusion promises to be an energy source which is potentially safe and environmentally benign. Radiological and proliferation hazards are much smaller than for fission power plants. The atmospheric impact is negligible compared to fossil fuels, and adverse impacts on the Earth's ecological and geophysical processes are smaller than for large‐scale renewable energy sources. The economics and costs of fusion power plants are still being studied, but appear comparable to those for other medium‐ and long‐term energy sources. The promise of affordable essentially unlimited supplies of clean, safe energy, free of political boundaries, has motivated a world‐wide research effort to develop this energy resource. The reactions of deuterium, tritium, and helium‐3, 3 He, having nuclear charges of 1, 1, and 2, respectively, are the easiest to initiate. These have the highest fusion reaction probabilities and the lowest reactant energies. Two diverse technical approaches to fusion power, magnetic confinement fusion, also known as magnetic fusion energy (MFE) and inertial confinement fusion, also known as inertial fusion energy (IFE) are being pursued worldwide. These form the basis of a large number of fusion research programs. Fusion energy research is also the primary avenue for the development of plasma physics as a scientific discipline.