Lämpösähköistä

Lämpösähköistä, also known as thermoelectricity, is a phenomenon that involves the direct conversion of temperature differences into electric voltage, and vice versa. This effect is based on the properties of certain materials that exhibit a direct relationship between heat flow and electrical current.

The primary thermoelectric effects are the Seebeck effect and the Peltier effect. The Seebeck effect describes how a voltage is produced when there is a temperature difference across a thermoelectric material. Conversely, the Peltier effect states that when an electric current flows through a junction of two different thermoelectric materials, heat is either absorbed or released at the junction, creating a temperature difference.

Thermoelectric generators (TEGs) utilize the Seebeck effect to convert waste heat into electrical energy. These devices are solid-state, meaning they have no moving parts, which makes them reliable and durable. Applications for TEGs include powering remote sensors, recovering waste heat from engines and industrial processes, and in niche applications like powering space probes where traditional power sources are impractical.

Thermoelectric coolers (TECs), also known as Peltier modules, employ the Peltier effect to create a cooling effect. By passing a current through the module, one side becomes cold while the other becomes hot. TECs are used in small-scale refrigeration, portable coolers, and in electronic cooling applications where precise temperature control is needed.

While thermoelectric technology offers advantages like solid-state operation and no moving parts, its widespread adoption has been limited by relatively low energy conversion efficiencies compared to conventional methods. However, ongoing research and development are focused on improving material properties and device designs to enhance efficiency and reduce costs, paving the way for broader applications in energy harvesting and cooling.