Body Heat Powers Wearable Devices

I'm wondering how 20 uW/cm² compares with the output of a comparable size solar cell under ambient light conditions.

And that Fluke meter has a 9V battery in it!!

I am playing around with some Mono-crystalline (semi flexible) solar cells currently:

Efficiency: 21.8%, Working Voltage: 0.574 V, Working Current: 5.83 A ~ 3.34W

Since each cell is ~ 25 sq" (161.29 cm^2), that produces ~ 0.0207 W/cm^2.

That of course, is under full sunlight, but that is still 1000 times the power/cm^2 of this TEG device. I don't think it would be as bad as the TEG device even if it was lit by a single candle.

The efficiency of solar sells - well sucks. But TEGs are worse.

I noticed in the last sentence it says, " Since the new TEG is scalable, it can easily be made larger to generate more power if needed.

OK, I am not familiar with TEG's.

I know that the average mean temperature of most male's is 94.4-94.6

And the average mean temperature of most female's is 94.6-94.8, with some @ 94.9

So, the male's devices would/should need to be made larger to compensate for the produced voltage/efficiency difference ?