Perpetual Motion Hydroelectric Generators?

[Nitack]

Scientists Create Metal That Pumps Liquid Uphill

Scientists Create Metal That Pumps Liquid Uphill

ScienceDaily (June 3, 2009) — In nature, trees pull vast amounts of water from their roots up to their leaves hundreds of feet above the ground through capillary action, but now scientists at the University of Rochester have created a simple slab of metal that lifts liquid using the same principle—but does so at a speed that would make nature envious.

I read through this article, some of it was over my head, some of it not. However, the article notes that this new technology/methodology can create a surface on metal that can wick water in a set direction, even against gravity. My question, could this be used in such a way to lift water, energy free, and allow gravity to pull it down through a turbine causing electrical generation? It would take a very large scale implementation to do and a lot of time an energy to set it up (article notes that the process for changing the surface of the metal takes 30 minutes for the area the size of a quarter).

Before some one yells at me about perpetual motion being impossible (I already know this) read the full damn article to know what they are talking about first. It apparently has to do with very small etching on the surface of metal using very high powered lasers for femtoseconds. The interplay between molecular attraction, gravity, and evaporation seem to power the movement, but that is the part beyond my comprehension.

[Qfwfq]

Before going through the whole darn thing, I'll say why it's no use in the simpler case of capillary action: in order to continuously take water from the top, you break the effect which pulled the water up, bye bye continuous cycle. Now since gravity is a conservative field to the best of our knowledge and neither do molecular attractions and evaporation violate conservation, I'm pretty sure that an at least similar consideration would apply or else, if it can give a net round-the-circuit push, prolly it amounts to being a thermodynamic effect.

[CraigD]

Originally Posted by Nitack

Scientists Create Metal That Pumps Liquid Uphill

My question, could this be used in such a way to lift water, energy free, and allow gravity to pull it down through a turbine causing electrical generation?

I think I see what you’re getting at: something like this:

with the tube in the diagram made of the microscopically etched metal in described in the Science Daily article. Capillary action would draw liquid up, where it could return down via some sort of energy extraction device – the waterwheel and red power take off belt in the diagram.

The problem with this is that capillary effect – be it from everyday devices like household cleaning sponges, blood sampling pipettes, and oil lamp wicks, the natural kinds like sap vessels in plants, or the kind described in the article, perform work by drawing a liquid through a tube or along a surface to where there was formerly no liquid. Once filled with liquid, these devices stop doing work, and require work (energy) to have the liquid expelled, if desired. Many capillary devices are disposable, such as the test strips in a glucometer, internded for the single-use task of delivering a liquid from one end of a channel to the other. In others, the liquid is expelled using air pressure, such as from a small squeeze bulb. In the case of a lamp wick, the liquid is removed by burning it.

An attempted perpetual motion machine like the one sketched above would fail, because its capillary tube would fill with water, but not release it to return via the waterwheel without outside power greater than the power generate by wheel.

It’s tempting to think that some precisely etched microscopic surface might be able to overcome this failing, but all would be variations on the old perpetual motion machine “ratchet” fallacy, which like most perpetual motion-related fallacies, involves a mechanical device that produces more energy than it consumes.