128 Electrical Power Systems Technology
since it exists as heavy hydrogen in sea water. The use of such an abun-
dant fuel could solve some of our problems that are related to the deple-
tion of fossil fuels. Another outstanding advantage of this system is that
its radioactive waste products would be minimal.
The fusion process results when two atomic nuclei collide under con-
trolled conditions to cause a rearrangement of their inner structure and,
thus, release a large amount of energy during the reaction. These nuclear
reactions or fusings of atoms must take place under tremendously high
temperatures. The energy released through nuclear fusion would be thou-
sands of times greater per unit than the energy from typical chemical reac-
tions, and considerably greater than that of a nuclear-fission reaction.
The fusion reaction involves the fusing together of two light elements
to form a heavier element, with heat energy being released during the re-
action. This reaction could occur when a deuterium ion and a tritium ion
are fused together. A deuterium ion is a hydrogen atom with one addi-
tional neutron, and a tritium ion is a hydrogen atom with two additional
neutrons. A temperature in the range of 100,000,000° C is needed for this
reaction to produce a great enough velocity for the two ions to fuse togeth-
er. Sufficient velocity is needed to overcome the forces associated with the
ions. The deuterium-tritium fusion reaction produces a helium atom and
a neutron. The neutron, with a high enough energy level, could cause an-
other deuterium-tritium reaction of nearby ions, providing the time of the
original reaction is long enough. A much higher amount of energy would
be produced by a nuclear-fusion reaction than by a fission reaction. There are
several different techniques being investigated for producing nuclear fu-
sion. At this time, each is still in the theoretical development stage.
NUCLEAR-FUSION METHODS
Several methods are being considered today for using the heat from
nuclear fusion to generate electrical power.
Magnetic-confinement Method
One method is called magnetic confinement. The proposed design of
a magnetic-confinement power system is shown in Figure 5-6. At present,
it is thought that fusion reactors could be economical if the reaction can
be carried out in an intense magnetic field provided by superconducting
magnets. The magnet and the magnetic-field designs are very complex,