TEG-embedded T-shirt (left) and TEG armband (right).

Researchers at North Carolina State University have developed a new design for harvesting body heat and converting it into electricity for use in wearable electronics.

The new design begins with a layer of thermally conductive material that rests on the skin and spreads out the heat. The conductive material is topped with a polymer layer that prevents the heat from dissipating through to the outside air. This forces the body heat to pass through a centrally located thermoelectric generator (TEG). Heat that is not converted into electricity passes through the TEG into an outer layer of thermally conductive material, which rapidly dissipates the heat.

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