All really baaad Matrix jokes aside ...
Back in the mid 90's when I still on active duty, I saw countless "Battlefield of the Future" articles. Some of them showed (based on then current technology) what the soldier or marine could be equipped with: tactical battlefield communications, battlefield management (computer support), GPS, electro-optical sights of all sorts, NVG's, etc. So you have all this electronic junk that you expect the soldier to carry in addition to what he needs to "kill people and break things" (his basic mission) and it's all powered by different kinds of batteries.
drutort,
With a thermal generator of the sort they are talking about, all you need is a temperature difference. It doesn't matter if the soldier is warmer or cooler than the environment. All you need is a simple means of reversing the polarity and a simple full wave bridge rectifier will do that.
hewdew, we can do that now. It's called catching a cold.
My whimsical question is this:
Can we generate more power if we hold hands (batteries in series)?