How can electricity be generated from raindrops? Learn about this new technology’s claims.

Until now, sunlight has been considered essential for generating electricity via solar panels, but work is now underway on technology to generate power from raindrops as well. Find out exactly how electricity is produced from a single raindrop.

Previously, the mention of solar energy immediately brought to mind sunlight and solar panels; however, scientists are now viewing rain as a potential source of electricity. Researchers in Seville, Spain, have developed a technology that aims to generate electricity using the kinetic energy of falling raindrops. This involves applying a special coating—only 100 nanometers thick—to the surface of a solar panel.

According to the researchers, this system is designed to harvest energy from both sunlight and rain. However, results are currently limited to laboratory tests, and the technology has yet to be tested on actual solar panels.

How can electricity be generated from raindrops?

This technology relies on the “triboelectric effect.” When two surfaces come into contact and then separate, an exchange of electric charges occurs between them. This principle is utilized with raindrops: when a raindrop falls onto a specially prepared fluorinated surface and slides across it, distinct electric charges are generated on the water and the surface. Electricity is not produced simply by the drop resting on the surface; the charge is generated when the drop moves across the surface, creating a current within the circuit.

The 100-nanometer coating is key.

Researchers have developed a fluorinated polymer coating that is 100 nanometers thick. It is over 90% transparent, ensuring that sunlight can still reach the solar cell without significant obstruction when it is not raining. Testing has revealed that a single raindrop can generate a peak voltage of up to 110 volts. In this scenario, solar panels could potentially generate additional electrical output from raindrops alongside their standard solar power generation.

Use with Perovskite Solar Cells

This technology can be utilized with halide perovskite solar cells. While these cells are known for high light absorption and efficiency, a major drawback is their susceptibility to moisture. This specialized coating serves a dual purpose: it protects the perovskite cells from water while simultaneously enabling energy harvesting from raindrops.

Potential Applications

While this technology is not expected to generate enough electricity to power an entire household’s appliances, it could be used to power devices such as remote sensors, weather monitoring stations, highway signage, and small auxiliary lights. However, the technology has currently only been tested in a laboratory setting.