Rain-powered generator makes 60V for flood control without batteries

A research team at South Korea’s Ulsan National Institute of Science and Technology (UNIST) has developed a rain-powered generator that converts the mechanical energy of falling raindrops into electrical signals for flood control and smart drainage systems. The device, named the Superhydrophobic Fiber-Reinforced Polymer Droplet-Based Electricity Generator (S-FRP-DEG), uses carbon fiber-reinforced polymer (CFRP) composites to harvest energy instantly when rain hits its negatively charged, superhydrophobic surface. This design leverages charge transfer from positively charged raindrops to generate up to 60 volts per droplet without relying on external power or batteries, and it is durable enough for long-term outdoor use due to CFRP’s corrosion resistance. The generator’s surface is enhanced with lotus-leaf-inspired texturing and coatings to improve water repellency and prevent dirt accumulation, addressing common issues in metal-based droplet generators such as corrosion. Laboratory tests demonstrated that multiple units connected in series could power LED lights