A group of researchers from Singapore have presented a revolutionary technology that allows generating electricity from raindrops. Their discovery, published in the journal ACS Central Science , could be a breakthrough in the field of alternative energy, especially for urban spaces.
The key to the invention is the so-called “cork flow,” which occurs when water falls through a narrow vertical tube. The researchers found that when raindrops fall through a 32-centimeter, 2-millimeter-wide polymer tube, they form short columns of water, with air pockets between them. This flow, combined with the electrical properties of water and materials, allows current to be generated.
The setup is very simple: water flows out of a metal needle, forming drops that fall into a tube. The charged water flows down, separating the electrical charges that are captured by wires located at the top of the tube and in a reservoir cup at the bottom.
In further experiments, the team found that using two tubes in parallel or in series doubled the amount of electricity produced. By directing the flow into four tubes simultaneously, they achieved continuous powering of 12 LEDs for 20 seconds.
According to one of the authors of the study, Xiaoling Soh, this technology could be a promising alternative to hydroelectric power plants. It does not require large reservoirs or rivers and is compact, making it suitable for installation on the roofs of buildings in cities.
This technology could potentially be integrated into smart home systems, providing power for sensors, lighting, and small devices. It also opens up prospects for autonomous power in resource-constrained or emergency situations.
Chinese scientists have previously presented another similar development - a triboelectric nanogenerator that uses liquid-solid contact to harvest energy from rain. However, the Singaporean installation looks simpler, more reliable and more adapted to everyday use.
