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Engineers Found a Way to Generate Electricity From Thin Air
If it can be scaled up, Air-gen technology could power everything from iPhones to car charging stations

Green energy, as far as we’ve implemented it, is at best a shade of greenish-brown — army, perhaps, or olive. Solar farms harness the sun’s renewable energy but require large swaths of land and rare Earth metals. Wind power has a minimal carbon footprint, but, like solar, gets stored in batteries made from lead and lithium. Nuclear power is appealingly low carbon, but the risk of another Chernobyl is hard to stomach. All of these options are a huge improvement over coal power, but there’s real pressure to find an energy source that’s truly scalable, cheap, and 100% green.
Last week, scientists from the University of Massachusetts Amherst rose to the challenge, presenting a low-cost device they call the Air-gen, which generates electricity from thin air — enough to theoretically power devices like cellphones and electric cars. And since it doesn’t require harsh chemicals to produce, “the whole process,” corresponding author and assistant electrical engineer professor Jun Yao tells OneZero via email, is “green.”
Improbable as it sounds, the device’s technology is based on a natural phenomena: electricity-generating threads of proteins, called nanowires, that emanate out of a tiny bacteria called Geobacter sulfurreducens (a plush toy version of the bacteria looks like a Cheeto with tentacles). In the paper they published in the journal Nature last week, Yao and his co-authors describe their key discovery: Moisture suspended naturally in the air is the “driving force” behind the electricity-generating ability of the nanowires.
Think back to high school physics. Electricity is basically the flow of electrons, the negatively charged particles that circle atoms, from an area of high charge to an area of low charge. Water can be a good source of these charged electrons, if it can be broken up into its building blocks, hydrogen and oxygen.
The team theorizes that when a tangle of the nanowires is pressed into a mesh-like film, water from the air collects only at the top of it and breaks up into two Hs and an O, freeing up the water’s electrons. This gives the…