Rain could one day become a source of clean electricity, according to a group of scientists in Singapore. Their experiments have been able to generate power from water droplets falling through a tube.

Raindrops may seem harmless as they slide down windows or trickle through gutters. But inside each drop lies a powerful secret. When water flows through certain surfaces, it creates electrical charges ...

When a solid and a liquid come into contact, charged entities on both sides push one another apart. This phenomenon is known as charge separation, and it creates an electric double layer—a layer each ...