ABSTRACT
The discovery of thermoelectricity was done a long ago. In 1821,
Thomas J. Seebeck observed that the needle of a compass was
deflected in the vicinity of two metallic conductors connected to
one another when different temperatures prevailed at the joints.
The degree of deflection here was proportional to the temperature
difference. The reason for the movement of the compass needle was
an electrical field that had apparently been created by the difference
in temperature between the conductors. The effect observed by
Seebeck also functions in the opposite direction and was first
described by Jean C. A. Peltier in 1834: If electricity is applied to
the two connected conductors, a temperature gradient occurs at
the contact points. Heat energy is transported from one connection
point to the other, leading to a cooling effect.