Similar to Christopher Columbus navigating the vast waters of the Atlantic, Thomas Seebeck helped to plot the way for the field of thermoelectrics. Seebeck’s discoveries in the 19th century have stood the test of time and continue to be used to this day.
Along with fellow physicists Jean Peltier of the Peltier effect and Lord Kelvin of the Thomson effect, Seebeck created the foundation for the field of thermoelectrics as we know it today.
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WHAT IS THE SEEBECK EFFECT?
Thomas Seebeck discovered that when dissimilar metals are exposed to a variance of temperature with distance, they produce an electric current. The Seebeck effect (also known as the Peltier-Seebeck effect) is the foundation of thermocouples and thermopiles. The metals that are commonly paired together to create the Seebeck effect are constantan with copper, iron, chrome, or aluminum. However, there are also a number of other wire pairings that can be used to create this particular effect. Together with the Peltier and Thompson effects, the Seebeck effect completes the triad that is the basis for thermoelectrics.
Seebeck Effect Equations
There is more than one Seebeck effect equation and the equation a person uses will naturally depend on the type of Seebeck device one is using and how much voltage he or she needs the device to produce.
The Seebeck effect is calculated using a reversible closed Carnot cycle. Put in simple terms, it looks like this: dQ / dt = (Пa - Пb)1. This calculation is used to determine the heat rate for the electric current. To determine the co-efficient calculated by the model, the following equations are used: Пa = kTln (ɳL) and Пb = kTln (ɳR). Other equations can be found here and here.
How are Seebeck Devices Used?
Seebeck generators are also commonly known as thermoelectric generators (TEG’s). They convert heat into energy and are used for low power remote applications and applications that would not be able to support a large heat generator. Seebeck generators do not have moving parts, operate 24/7 and can be used in all types of weather. What is more, they do not require battery back up.
Companies that build and/or manage gas pipelines use thermoelectric generators in a number of ways. These generators provide cathodic protection, make radio communication a possibility and can be used for telemetry. Thermoelectric generators are also used as off-grid power generators in remote areas and as back-up generators for solar panel energy creation devices.
Seebeck Devices in Consumer Products
Automotive thermoelectric generators are used in many types of cars. They take waste heat produced by the engine and turn it into energy, thus increasing a car's efficiency. Given the fact that 40% of a car engine's energy is lost via exhaust gas heat, it is clear that using a thermoelectric generator inside a car can represent significant energy savings. What is more, thermoelectric generators also drastically reduce the amount of emissions that a car produces, thus helping to make vehicles much more environmentally friendly than they were in times past.
Industrial Uses of Seebeck Devices
Seebeck generators are becoming increasingly popular in the manufacturing industry. Because they can take waste heat (that would have been released into the environment) and turn it into energy, they are extremely useful for any company that generates heat in the creation of its products and/or services. Increasing the efficiency of generators can save a company money and also reduce CO2 emissions, which helps protect the environment.
Evolution of the Seebeck Effect
While Thomas Seebeck was the first to discover that dissimilar metals can, under the right circumstances, create an electrical current, he was by no means the last person to be interested in this phenomenon. The discovery of the Peltier Effect and Thomson Effect were made based on Seebeck's work. In 2008, physicists discovered the Spin Seebeck Effect, which can be applied to a magnetized metal and causes electrons to rearrange themselves in accordance with their spin. The Spin Seebeck Effect has the potential to enable companies to create faster, smaller and more energy efficient microchips and spintronic devices.
Thermoelectric energy generation has a great deal of potential. At present, it can enable companies as well as average individuals to save a great deal of energy and reduce emissions. It can be used to generate power in instances where other generators would not be able to operate. However, there is much more in store for the future. As ongoing research enables the scientific community to discover new uses for Seebeck devices, they are certain to become both more commonplace and more efficient.
Using the Seebeck effect, II-VI Marlow has created thermoelectric modules designed for temperature cycling applications where high reliability is essential. These power generators utilize existing temperature differentials to provide reliable, renewable energy for projects from low-power wireless sensors to large-scale electricity generation. Visit II-VI Marlow to browse our complete product line of power generators and read more about how thermoelectric generators work.
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