Fusion Energy: Bringing the Power of the Sun to Earth

For over fifty years, the development of controlled nuclear fusion has been the holy grail of high energy physics. When such technology is achieved, in which a controlled fusion reaction generates more energy than it takes to start it, then the world will change. Limitless energy, using the same nuclear process that powers the sun, will be within the grasp of humankind.

How Nuclear Fusion Works

Unlike nuclear fission, which involves the splitting of an atom into two atoms, nuclear fusion involves the fusion of two atoms into one atom. In a fusion reactor, in general, two hydrogen atoms are brought together to form a helium atom, a stream of neutrons, and a great deal of energy. There are several types of nuclear fusion reactions, most of which involve deuterium and/or tritium, isotopes of hydrogen.

A proton-proton chain reaction is the process by which stars like the sun generate energy. First, two pairs of protons fuse to form two deuterium atoms. Then each deuterium atom fuse with another proton to form a helium 3 atom. Two helium 3 atoms fuse to form a beryllium-6 atom. Then beryllium-6 decays to form two helium-4 atoms. This reaction produces a great deal of radiation and high energy particles.

A deuterium-deuterium reaction fuses two deuterium atoms to form a helium-3 atom, a neutron, and great deal of energy. A tritium-deuterium reaction fuses a tritium atom with a deuterium atom to form a helium-4 atom and a high energy neutron.

Thus, a nuclear fusion process is simple in concept/ However it is difficult to achieve under controlled conditions.

Conditions for Nuclear Fusion

The one problem with achieving nuclear fusion is that protons tend to repel one another, sort of like two magnets. To counteract this tendency, one has to apply high temperature and high pressure.