Generating Electricity from Air, with Jun Yao

A Need for Clean EnergyEnergy harvesting from environmental sources is key to mitigating the harm associated with fossil fuels. Renewable energy is generated from naturally replenishing resources, and common sources include solar, wind, and water. Currently, renewable energy only makes up roughly 20% of all U.S. electricity, and many of these sources are intermittent – they do not produce continuous energy on a 24/7 basis. These sources of clean energy often require a large amount of land and specific weather conditions, and can face various barriers to being cost-effective. Researchers at UMass Amherst have developed a method to harness energy from air humidity, potentially revolutionizing clean energy production. Dubbed “Air-gen,” this device has the capacity to produce continuous clean electricity.How does Air-gen Work?The prototype device is small in size, comparable to the size of a fingernail, and as thin as a strand of hair. The device contains tiny holes, known as nanopores, that allow water vapor in the air to pass through. As the water molecules travel through the nanopores, the molecules’ contact with the walls of the device creates small charges. The frequency of this contact causes a charge imbalance in the upper and lower parts of the device effectively creating a battery. Despite its current small-scale energy output, stacking multiple Air-gens has the potential for significant electricity generation.Why Air EnergyThe “Air-gen Effect” would offer a sustainable, accessible source of continuous clean energy as it utilizes humidity that is always present in the air. Air-gen technology has the ability to suit most environments, operating 24/7 day and night and even indoors. The devices can be stacked upon each other to increase energy output without increasing the footprint of the device. Air-gens do not require any specific material in their construction as well, minimizing the amount of material extraction needed in comparison to other forms of renewable energy. Clean Energy ChallengesThe Air-gen team faces challenges in efficiency, material selection, and scalability. They aim to reduce the number of devices and space needed to generate significant amounts of energy, as well as optimize the device by finding ideal device materials that can operate across different climates. It is unclear how long these developments will take. Air-gen is one of many possible solutions, all of which faces challenges, both technical and economic. A competing solution is nuclear energy, which produces large amounts of energy and has grown in use globally. Nuclear power produces renewable, clean energy without pollutants or greenhouse gas emission, however, the byproduct of nuclear energy is radioactive material. Geothermal energy is another clean energy solution that drives turbines using steam power. Geothermal energy is flexible as it can run consistently regardless of time or weather, like the Air-gen, and also has a minimal footprint, but is limited in its location dependency, costs to start, and earthquake risks. There are many ideas for clean energy generation and storage, but finding the right solutions is only part of the challenge. About the GuestJun Yao is an associate professor of electrical and computer engineering at the University of Massachusetts, Amherst. Yao’s other work involves developing novel nanoelectronic and bioelectronic sensors and devices for health/physiological monitoring. Yao received his Ph.D. in Applied Physics from Rice University.  Further ReadingEnergy from Almost Any Material (Washington Post,2023)Humid Air into Renewable Power (The Guardian, 2023)Air Humidity and Energy Harvesting (Advanced Materials, 2023)Jun Yao speaks on Harvesting Electricity from Air For a transcript of this episode, visit https://climatebreak.org/generating-electricity-from-air-with-jun-yao/