Thermoelectric cooling uses electric power to create a temperature difference between two kinds of material. The thermoelectric effect is a basis for thermoelectric cooling and used in thermoelectric coolers, heat pumps, heaters, and thermoelectric generators. When a current runs through a thermoelectric device, heat is moved from one side of it to the other. The effect can go two ways. It can convert temperature differences into electric voltage or use electricity to make temperature differences, which is referred to as the Peltier effect.
A Peltier heat pump, also called a thermoelectric heat pump, transfers heat from one side of the unit to the other. It will extract thermal energy from one side, which cools it, and put this heat on the other side, which heats it. A heat sink has to be used or the device will become too hot and fry itself. These devices can cool beer, warm coffee, run a small refrigerator, or run a warming oven.
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Thermoelectric coolers (TEC), or thermoelectric cooling systems, have a matrix of semiconductor pellets between two big electrodes. When a DC voltage source is connected between them, the negatively charged side will become cooler and the positively charged side will become hotter. The negative electrode will have contact with whatever is being cooled, like a device or component. The positive electrode is connected to a heat sink that will dissipate the energy.
A thermoelectric cooling system can be found in a number of devices. Such devices are found in computers to cool microprocessors and power amplifiers. They are used in spacecraft to help moderate the extreme temperature fluctuations between the dark side and the sunlit side. They can also be found in portable coolers used in camping, various kinds of electronic equipment such as digital cameras, and in dehumidifiers.
A thermoelectric generator, on the other hand, is the opposite of a thermoelectric cooler but still uses the thermoelectric effect. In the generator, temperature differences between the two sides of the unit are used to generate electrical power. Both of these devices are similar in structure and the materials used.
Even though thermoelectric cooling is less efficient than refrigeration, it has some distinct advantages. If cooling on a small scale is required, then thermoelectric cooling can be cheaper and more practical than refrigeration. It doesn’t have any mechanical moving parts, it is portable, durable, lasts a long time, and doesn’t need much maintenance.