Why isn't fusion used in the production of nuclear power?

Answer 1

Fusion is not used in the production of nuclear power, other than in the Sun and stars, due to technological problems, primarily in containment. The Sun has it easy, so to speak, because its large gravity and mass causes the temperature and pressure necessary to initiate and sustain fusion, while its gravity also eliminates the need for containment. Attempting to do this on the Earth would not work because the size of the reactor would vastly exceed the size of the Earth. The alternative, building a containment vessel, is not working because the many millions of degrees of heat required for the plasma would destroy any vessel we have. Building a magnetic containment vessel, such as the tokamak (ITER) shows promise, but the technical problems of having supercold magnets in close proximity to superhot plasma are very overwhelming. First fusion for this project is set for 2019, and my guess is that commercial power from fusion is at least 50 to 100 years away.