It works by pulling water up into the filter via capillary action and then blowing cool air through the water to disburse it into the air. No heat is produced, reducing the likelihood of mold growth in the unit.
All of this, though, is beside the point.
I wondered: capillary action, conservation of energy -- two great tastes that taste great together. How does one obey the other?
Go ahead, guess. Or maybe you know. In which case: showoff.
I looked it up on the internet ("We Have the Technology (TM)") and confirmed my theory that capillary action is powered by ambient heat. It's like this, nutshelled: temperature is a measure of random movement of molecules in fluids, and these random movements cause the miniscus of the fluid to slowly climb the sides of the capillary tube, dragging the remainder of the water along via surface tension. The kinetic energy of the random movements -- the heat -- is transformed into potential energy -- the height -- and the lack of heat-proof shielding allows the temperature to equalize with the rest of the environment, slowly drawing in heat as the capillary action continues.
Or something like that. But really, it's all beside the point.
The usenet thread which learned me all of this was initiated by a 15 year old who had set up the following experiment:
Take a bucket of water. Place a paper towel with one end in the water, and the other hung over something such that it drips onto a paddle wheel and then back into the bucket. Sit. Watch.
The movement of the paddle wheel is miniscule, he said, but the system hasn't stopped for a couple of weeks. Where is the energy coming from?
So some asshole, rather than answering his question, gives him shit about how his "theoretical" wheel would have stopped long ago, and how he's a big important guy, and how these unrealistic expectations of perpetual motion are worthless, and how the kid needs to be more rigorous.
Wow, thanks. Sometimes I forget why kids hate school. It's because of pricks like you, buddy. You could have just answered him, or told him you didn't know, or even applauded his interest. But you didn't, because you're an asshole, and that is the point.