Harvesting Energy from Falling Droplets

Abstract

Two centuries ago, archaeologists digging through the ruins of ancient Babylon made a fascinating discovery—clay tablets written in cuneiform dating back to circa 1800 BCE. These tablets included descriptions of superstitions whereby priests divined the future through the patterns formed by oil poured on water. This ancient text represents the earliest known literature reference to the hydrophobic effect [1]. Now, two independent teams of modern scientists have used this idea, along with other concepts described roughly two millennia ago, to develop remarkably efficient electrical nanogenerators with no moving parts [2, 3]. The nanogenerators are based on several phenomena relating to water and electricity described by the classical Greek philosopher Plato. And the key to making the nanogenerator so efficient is to tag team these phenomena with the hydrophobic effect described in the Babylonian cuneiform tablets.