Moving water from one position to another, higher one usually requires power — be that your arms to carry it or a motor to drive a pump. But this device can actually move liquid uphill without any external energy source.
The powerless pump has been created by researchers from Beihang University in Beijing, China. It’s real enough, though it only works over heights of around 1cm at the moment. It works because of clever use of a water-repelling — or superhydrophobic — surface, created using copper mesh that’s been treated with an alkali solution. New Scientist describes how it works:
The team placed this mesh at the bottom of a vertical plastic pipe with a right-angle joint at the top, which was filled with a small amount of water. The superhydrophobic mesh repels the water and stops it from falling, but doesn’t transport it upwards. That happens when a small droplet of water is placed underneath the mesh and gets drawn into the column above, causing the top of the column to rise slightly. Once enough water has been lifted to fill the pipe, it spills out the other end.
The researchers reckon that the trick could be used in small-scale fluid transport devices, like those used to mimic biological functions in laboratories. Though one also wonders if a cascade of them couldn’t perhaps be used to move water uphill without the need for any energy at all. Well, we can dream.