Peltierilmiössä

Peltierilmiö, discovered by Jean Charles Athanase Peltier in 1834, is a thermoelectric phenomenon where a temperature difference is created across an electrical junction between two different conductors when an electric current is passed through it. Specifically, when current flows in one direction, heat is absorbed at one junction, causing it to cool, while heat is released at the other junction, causing it to warm up. Reversing the direction of the current reverses the direction of heat flow, so the previously cold junction becomes hot and vice versa. This effect is directly proportional to the current and depends on the properties of the materials forming the junction. The magnitude of the heating or cooling is determined by the Peltier coefficient, which is specific to each pair of materials. The Peltier effect is the inverse of the Seebeck effect, which generates a voltage from a temperature difference. Applications of the Peltier effect include solid-state cooling devices, such as small refrigerators and temperature controllers for electronic components. These devices, often referred to as thermoelectric coolers (TECs) or solid-state heat pumps, are widely used due to their lack of moving parts, compactness, and precise temperature control capabilities. However, their efficiency can be lower compared to traditional refrigeration methods in larger-scale applications.