A thermoelectric modules for power generation has an essentially different design than a thermoelectric Peltier element which is used for cooling. The market offers plenty of thermoelectric generator modules, manufactured by the Peltier cell technology. That is soldered to the ceramic plate between the elements. All these modules have in common that they are not intended however to a continuous operation. The fact that the temperature difference in the thermoelectric Peltier modules is 70 ° C.
And the technology for the manufacture of generators thermoelectric modules, must be made for the big difference in temperature and the corresponding thermal expansion. Thermoelectric module for generating should be a temperature difference no less than 200 ° C degrees. Otherwise, the conversion efficiency is too low. That is, more than three times higher than the one which is designed technology ceramic Peltier module.
Here you can see what it looks like and what are the characteristics of a real thermoelectric generator unit for continuous operation for decades at a temperature difference of 400 ° C.
Medium temperature thermoelectric modules for power generation TELGEN encapsulation enamel
Thermoelectric modules for power generation TELGEN with steel vacuum sealed case.
Such harsh operating conditions have specific requirements for antidifuzionnym layers, conductive contacts switching the thermoelectric material and its protection from atmospheric oxygen and sublimation.
An element of the thermoelectric generator unit is a thermoelectric battery:
Thermoelectric batteries of different modifications
Thermoelectric medium-themperatures modules for power generation TELGEN
Р-type – GeTe
N-type – PbTe
The heat flux density– 8 W/cm2.
Efficiency – 6%
The temperature of the cold side– 80°C
The temperature of the hot side- 450°C
Voltage – 3,5V
Current – 9A
Nominal power (in gas generator) – 31 W
Maximal power – 55 W
Operation Life – 20 years
Dimensions — 60х130х12 mm
* Note: a thermoelectric power generating module depends on the output of the heat flow passing through it. The stand can be organized much higher heat flux compared with real thermoelectric generator. Therefore, the maximum power specified in the data sheets for the thermoelectric modules to implement in products can not be.