Thermoelectric Cooling

the absorption of heat when an electric current is passed through a thermal converter.

The essence of thermoelectric cooling lies in the appearance of a temperature difference at the junctions of the thermal converter; at the cold junction, heat is absorbed from the substance to be cooled, and the heat is transferred to the hot junction and later to the environment (seePELTIER EFFECT). Concurrently with the generation of cold, heat is liberated in the circuit of the thermal converter and transferred to the cold junction by conduction. The resultant characteristic of the cooling capacity of the thermal converter used for thermoelectric cooling is the efficiency Z = α²/ρλ, where a is the thermoelectric power, λ is the specific heat conductivity, and p is the specific electric resistance. Semiconductors (Z = 1.5–3.5 deg^–1)—for example, triple alloys of antimony, tellurium, bismuth, and selenium—are ordinarily used for producing the thermal converters for thermoelectric cooling. Thermoelectric coolers are simple in design, have no moving parts or coolants, and are safe in use but are wasteful of energy (the specific consumption of electricity is 6–8 times greater than in compressor refrigerators). Thermoelectric cooling is ordinarily used in installations with a refrigerating capacity of up to 100 watts, which find practical application in electronics, vacuum technology, instrument-making, and medicine.