Thermoelectric refrigerator sometimes called a
thermoelectric cooler module or Peltier cooler is a semi
conductor based electric component that functions as a
small heat pump. By applying a low voltage direct current
(DC) power source to a thermoelectric cooler module,
heat will be moved through the module from one side to
the other [1]. One module face, therefore, will be cooled
while the opposite face simultaneously is heated. Both
thermoelectric refrigerators and mechanical refrigerators
are governed by the same fundamental laws of
thermodynamics and both refrigeration systems; although
considerably different in form, function in accordance
with the same principles. In a mechanical refrigeration
unit, a compressor raises the pressure of a refrigerant and
circulates the refrigerant through the system. In the
refrigerated chamber, the refrigerant boils and in the
process of changing to a vapor, the refrigerant absorbs
heat causing the chamber to become cold. The heat
absorbed in the chamber is moved to the condenser where
it is transferred to the environment from the condensing
refrigerant. In a thermoelectric cooling system, a doped
semi-conductor material essentially takes the place of the
refrigerant, the condenser is replaced by a finned heat
sink, and the compressor is replaced by a Direct Current
(DC) power source. The application of Direct Current
(DC) power to the thermoelectric cooler modules causes
electrons to move through the semi-conductor material
[1]. At the cold end of the semi-conductor material, heat
is absorbed by the electron movement, moved through the
material, and expelled at the hot end. Since the hot end of
the material is physically attached to a heat sink, the heat
is passed from the material to the heat sink and then in
turn, transferred to the environment.