Micro Scavenging heat to power “internet of things” devices using Thermoelectric TEG modules. All of these scavenging devices require autonomous power to be effective and long lasting without scheduled service appointments to replace batteries. Most require maybe 1V at 20ma or more, Everybody wants to know if the body is capable of generating enough thermoelectric power from heat to provide a power supply to their device. The device is typically a passive sensor of some type. My answer is yes but it will take a very good design in order to maximize the amount of usable power. The main consideration is what module to use. A lot of surface area is needed to collect the heat thru the TEG module or module array. You will need a large surface to funnel heat thru the Thermoelectric power devices because the heat is very low grade maybe 20F to 30F Temperature difference or DT ( Delta Temperature) measured at the module hot face and cold face, NOT  from the ambient and skin. (Even high heat with low DT’s has the exact same principles).

In this case thick modules. What we mean by thick is tall elements that slow down the movement of heat flux so that a larger Delta Temperature will result and be sustained so both sides remain at different expanded temperatures. A large DT as we know will move more electrons more electrons more power pretty strait forward!

The best module for the JOB would be our TEG2-126LDT.

This module is 5.3mm high Graphite pads add .2mm to the height. This compares to a standard TEG1 Series module that averages 4mm tall! So, a little over 25% taller elements will create a much better result as far as Thermoelectric power produced in LOW DT application! Now you have to find places on the body or appliance that provide a lot of heat. Most of those places are for lack of a better descriptive hairy. The hairier the location the more heat is expelled to atmosphere Examples of this are the (Head, Underarms, Groin) . The rest is up to your design. Just make sure you have a good conductive path on the hot side to attract heat from a large area and also same size path on the cold side with good insulation in the middle to isolate the hot zone from the cold zone.

Other things to consider is distancing the TEG modules from each other so that they don’t compete for the same heat flux, that way you get maximum heat flow thru each module.

Contact: tecteg@rogers.com or call us we love to talk to you 1-905-751-1362