Research on harvesting electricity from humidity in the air

A team of engineers at the University of Massachusetts Amherst has recently shown that nearly any material can be turned into a device that continuously harvests electricity from humidity in the air. "We are opening up a wide door for harvesting clean electricity from thin air." "The air contains an enormous amount of electricity," says Jun Yao, assistant professor of electrical and computer engineering in the College of Engineering at UMass Amherst, and the paper's senior author. "Think of a cloud, which is nothing more than a mass of water droplets. Each of those droplets contains a charge, and when conditions are right, the cloud can produce a lightning bolt-but we don't know how to reliably capture electricity from lightning. What we've done is to create a human-built, small-scale cloud that produces electricity for us predictably and continuously so that we can harvest it." The heart of the man-made cloud depends on what Yao and his colleagues call the "Generic Air-gen effect," and it builds on work that Yao and co-author Derek Lovley, Distinguished Professor of Microbiology at UMass Amherst, had previously completed in 2020 showing that electricity could be continuously harvested from the air using a specialized material made of protein nanowires grown from the bacterium Geobacter sulfurreducens. "What we realized after making the Geobacter discovery," says Yao, "Is that the ability to generate electricity from the air-what we then called the 'Air-gen effect'-turns out to be generic: literally any kind of material can harvest electricity from air, as long as it has a certain property." Finally, because air humidity diffuses in three-dimensional space and the thickness of the Air-gen device is only a fraction of the width of a human hair, many thousands of them can be stacked on top of each other, efficiently scaling up the amount of energy without increasing the footprint of the device.