We Can Now Use Rain to Harvest Electricity

A team of scientists based in Singapore set up a clever system to capture electricity from ordinary raindrops, allowing people to harvest electricity directly from falling water without the need for large rivers or dams, making rain a viable, clean, renewable energy source.

“Water that falls through a vertical tube generates a substantial amount of electricity by using a specific pattern of water flow: plug flow,” explains Siowling Soh, Associate Professor of Chemical and Biomolecular Engineering, National University of Singapore. “Such pattern could allow rain energy to be harvested for generating clean and renewable electricity.”

The team set up a metallic needle that drips water into a conductive tube. Once the droplets slam into that tube, they break into pieces with air gaps between them, which is the pattern called plug flow. Each small column of water separated by air pockets flows down a 30-cm-tall by 0.2-cm-wide tube. Electrical charges separate naturally as droplets slam into that tube. Wires that are attached to both ends of each tube collect charges, producing usable electricity. By escaping the constraints of site-specific limitation, rain energy represents exciting possibilities for decentralised electricity generation options, thus contributing to a more sustainable and resilient energy future.