Environmental Engineering Reference
In-Depth Information
Nuclear fusion is a nuclear reaction in which two (or more) light atomic nuclei fuse
to form a heavier one. It is the opposite of nuclear fission, in which a heavy nucleus
such as uranium splits into two lighter fragments releasing a considerable amount
of energy (and radioactive products).
A fusion reaction occurs only when the interacting nuclei come very close to-
gether, which is difficult because they are both positively charged and there is a
strong repulsion among them. Therefore, fusion can only occur at very high tem-
peratures where the nuclei have high velocities. There were claims that it was pos-
sible to achieve “cold fusion” at room temperature, but they were not confirmed
independently.
Fusion occurs naturally in stars, including the Sun. This is the origin of the solar
radiation that reaches the Earth. Scientists are attempting controlled nuclear fusion
in laboratories in order to produce electricity, but there are numerous technological
problems with the process that have yet to be solved. The great advantage of nuc-
lear fusion over nuclear fission for the production of energy is that in the fusion
reaction very little nuclear waste is produced.
