New Device Harvests Electricity From Humidity

A team of scientists at the University of Massachusetts Amherst have created a new device that can harvest electricity from the humidity in the air. The device, named the Air-gen, uses nanowires and electrodes to generate an electrical current from moisture in the atmosphere. Details of the research have recently been published in the journal Nature.

The Earth’s atmosphere is filled with water, which takes the form of fog, clouds, or water vapor when condensed. The water from the humidity in the air releases its charge as it is absorbed by the layer of wires in the device. Paper co-author Jun Yao, an electrical engineer, commented, “We are literally making electricity out of thin air.” The device works in pretty much any environment, regardless of how humid it is.

The protein nanowires in the device are sustainably made using microorganisms. Scientists were working on using the protein nanowires as sensors that could be put in wearable electronic devices, but the sensors began to work before they even applied a current to them. In its current form, the device generates a sustained voltage of around 0.5 volts, enough electricity to power something like an LED light. The team said multiple devices could be used together to generate enough power to charge small electronics.

The team believes that their discovery could revolutionize green energy. The new device offers some key advantages over other renewable source including sun or wind energy. The technology used is renewable, non-polluting, and low-cost. The device can produce electricity at night, without wind, and even inside a building.

Harvesting energy from the environment offers the promise of clean power for self-sustained systems. As its next step, the team is planning to develop small Air-gen “patches” to power wearable devices and smartphones. The ultimate goal is to make large-scale systems that can produce enough electricity to power entire homes and businesses off the grid.