Fusion - Physics of a Fundamental Energy Source

Fusion Chart Graphic Not Loaded.

The fusion process powers the sun and other stars. In a fusion reaction, light nuclei combine, or fuse, to form heavier nuclei. Through fusion reactions, mass energy is converted to kinetic energy as described by Einstein's formula, E = mc2. In the sun, a sequence of fusion reactions named the p-p chain begins with protons, the nuclei of ordinary hydrogen, and ends with alpha particles, the nuclei of helium atoms. The p-p chain provides most of the sun's energy, and it will continue to do so for billions of years.

To make fusion happen on the earth, atoms must be heated to very high temperatures, typically above 10 million K. In this high-temperature state, the atoms are ionized, forming a plasma. This plasma must then be held together (confined) long enough that many fusion reactions occur. If fusion power plants become practical, they would provide a virtually inexhaustible energy supply because of the abundance of fuels like deuterium. Substantial progress towards this goal has been made, but many challenges remain.

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Introductory educational materials on fusion energy and the physics of plasmas.
Created by the Fusion and Plasmas Group of the Contemporary Physics Education Project (CPEP). CPEP is a non-profit organization of teachers, educators and physicists, with substantial student involvement. CPEP creates educational materials on contemporary physics topics for use in introductory physics classes. Page originally created by Jason Edson and Hannah Cohen.