In a fascinating scientific breakthrough, researchers have unveiled a method inspired by magic tricks to extract electricity from the surrounding air. A new study proposes a technique that allows any material to generate a continuous supply of electricity by harnessing the humidity in the atmosphere.
The process involves employing a pair of electrodes and a specially engineered material featuring minuscule holes, measuring less than 100 nanometers in diameter—almost a thousand times smaller than the width of a human hair. The tiny holes enable water molecules to pass through and generate electricity through the accumulation of charge carried by the water molecules, as detailed in a recent publication in the journal Advanced Materials. Essentially, this process mimics how clouds generate the electricity discharged in lightning bolts.
Given that humidity is a constant presence in the air, this innovative electricity harvester can operate at any time of the day, regardless of weather conditions. This distinguishes it from renewable energy technologies like wind and solar, which are reliant on specific weather patterns and can be less reliable.
Jun Yao, senior study author and an electrical engineer at the University of Massachusetts Amherst, envisions that this technology could lead to the widespread integration of electronics with “ubiquitous powering.” The discovery capitalizes on the fact that the air is brimming with electricity, considering that clouds carry an electric charge. However, extracting and utilizing electricity from lightning bolts has proven challenging.
Instead of attempting to harness electricity directly from nature, Yao and his colleagues realized they could recreate the phenomenon. In a prior study, they developed a device that employed a protein derived from bacteria to generate electricity from atmospheric moisture. Subsequently, they recognized that various materials could achieve the same outcome, as long as they possessed sufficiently small holes. The new research indicates that this type of energy-harvesting device, dubbed “Air-gen” by the study authors due to its ability to draw electricity from the air, can be constructed from “a broad range of inorganic, organic, and biological materials.”
Yao explains that the initial discovery was serendipitous, but subsequent work followed their intuition and led to the discovery of the Air-gen effect using diverse materials. As water molecules can travel approximately 100 nanometers in the air before colliding, when they pass through a thin material containing precisely sized holes, charge accumulates in the upper part of the material. This charge imbalance, similar to the phenomenon in clouds, effectively creates a battery that operates on humidity. Electrodes on both sides of the material then transmit the harvested electricity to power various devices.
Additionally, due to the materials’ thinness, they can be stacked in the thousands, generating multiple kilowatts of energy. Yao envisions a future where Air-gen devices range from small-scale versions powering wearables to larger systems capable of supplying electricity for entire households.
However, before realizing these possibilities, Yao acknowledges the need to optimize the collection of electricity over a larger surface area and explore the best methods to vertically stack the sheets for increased power without occupying additional space. Nevertheless, he remains optimistic about the technology’s potential, stating, “My dream is that one day we can obtain clean electricity anywhere and anytime by utilizing Air-gen technology.”
By Impact Lab