Thermoelectric generators (also known as Seebeck generators) are devices that convert heat (temperature differences) directly into electrical energy, using a phenomenon called the "Seebeck Effect" . Their typical efficiencies are around 5–8%, however there are currently modules with efficiencies as high as 12 - 14%. These are solid-state devices have no moving parts, unless designed with actively cooling (i.e. fans or pumps).
Thermoelectric generators, or TEGs, are devices that utilize one or more thermoelectric modules as the primary component/s, followed by a cooling system that can be either passive or active: such as an open air heat sink, fan cooled heat sink, or fluid cooled. These components are then fabricated into an assembly to function as one unit called a TEG.
When heat is applied to the hot side of a Thermoelectric Generator and the cold side is heat sunk to a lower potential temperature, electricity is produced. Almost any heat source can be used to generate electricity, such as solar heat, geothermal heat, even body heat. In addition the efficiency of any device or machine that generates heat as a by-product can be drastically improved by recovering the energy lost as heat.
What is a Thermoelectric Generator Module?
Thermoelectric Generator Modules are solid-state integrated circuits that employ three established thermoelectric effects known as the Peltier, Seebeck and Thomson effects. It is the Seebeck effect that is responsible for electrical power generation and thus the foundation of our business. The thermoelectric generator module is the heart of a thermoelectric generator (TEG).
Tegpro Thermoelectric Generator Modules available at Tegmart
How are thermoelectric modules made?
Their construction consists of pairs of p-type and n-type semiconductor materials with a high thermoelectric coefficient. Although many different materials can be used a bismuth telluride alloy is the most common material in use today. This material is sliced into small blocks, one forms the p-type conductor and the other the n-type conductor. Each pair forms a thermoelectric couple (TEC).
Most others use many thermoelectric couples that are sandwiched between two pieces of non-electrically conductive materials. It is also necessary for this material to be thermally conductive to ensure a good heat transfer, usually two thin ceramic wafers are used. This now forms what is called a thermoelectric module.
Now, if a thermoelectric module is being manufactured for use in a thermoelectric generator (TEG) it has its own unique requirements. First they need to have lowest internal resistance possible and high temperature silver solder connecting the wires. In addition, heat resistant insulation made from PTFE is used to coat the wires. Braided fiberglass sleeves can also be slipped over the wires providing further protection from the high heat. Special high temperature solder must be used that reflow at much higher temperatures than peltier modules used for cooling.
More information about Thermoelectric Generators (Wikipedia)
Videos of Thermoelectric Generators (YouTube)
Thermoelectric Generator Infomation Site (TEGPower.com)
More information Web Sites about Thermoelectric Generators below:
Basics of Thermoelectric Generators
Thermoelectric Generator Definitions
Basic information on the Thermoelectric Generator
More information on the Thermoelectric Generator
Electricity from Heat Educational Page
Stove Lite (World's First Wood Stove Powered Thermoelectric Lantern)
Devil Watt (Wood Burning Stove Thermoelectric Generators)
TEGPRO (Experts of TEG systems)
Tegulator (Complete line TEG power regulators Made in the USA)
Tegmart (Online Store: Wood Burning Stove Thermoelectric Generators, Energy Harverting Regualtors (Tegulator), and other Accessories)