In an advance that could deliver a constant stream of sustainable electricity, scientists have developed Air-gen, a device that uses a natural protein to create electricity from air moisture.

The laboratories of electrical engineer Jun Yao and microbiologist Derek Lovley at the University of Massachusetts Amherst (UMass Amherst) have created Air-gen with electrically conductive protein nanowires produced by the microbe Geobacter. The Air-gen connects electrodes to the protein nanowires in such a way that electrical current is generated from the water vapor naturally present in the atmosphere. The findings are published in Nature,
“We are literally making electricity out of thin air,” Yao said. “The Air-gen generates clean energy 24/7.”
The new technology developed in Yao’s lab is said to be non-polluting, renewable, low-cost and can generate power in areas with extremely low humidity.
The Air-gen device requires a thin film of protein nanowires less than 10 microns thick, the researchers said. The bottom of the film rests on an electrode, while a smaller electrode that covers only part of the nanowire film sits on top. The film adsorbs water vapour from the atmosphere. A combination of the electrical conductivity and surface chemistry of the protein nanowires, coupled with the fine pores between the nanowires within the film, establishes the conditions that generate an electrical current between the two electrodes.
The device produces a sustained voltage of around 0.5 volts across a 7-micrometre-thick film, with a current density of around 17 microamperes per square centimetre.
The researchers said that the current generation of Air-gen devices can power small electronics, and they expect to bring the invention to commercial scale soon. Next steps they plan include developing a small Air-gen “patch” that can power electronic wearables such as health and fitness monitors and smart watches, which would eliminate the requirement for traditional batteries. They also hope to develop Air-gens to apply to cell phones to eliminate periodic charging.
“The ultimate goal is to make large-scale systems,” Yao said. “For example, the technology might be incorporated into wall paint that could help power your home. Or, we may develop stand-alone air-powered generators that supply electricity off the grid. Once we get to an industrial scale for wire production, I fully expect that we can make large systems that will make a major contribution to sustainable energy production.”
I’ll believe it when I can wear it.
17uA / cm^2 at 0.5V is 0.085W per m^2
Less than 1/1000 what a solar panel can achieve. And while this will work even in the dark they’ll need to stack a lot of them vertically before it becomes useful.
Power a watch … maybe. Power a phone – no.
if my calcs are correct thats a whopping 0.085 wats per square metre
Seems amazing, but there must be some science behind it: something has to react to produce energy, the visual looks like electrostatic electricity. Until some credible explanation is given I’ll file this with unicorns and flying pigs as sources of energy.
If the mechanism for generating electricity is the moisture concentration gradient, the device will only work until equilibrium conditions are established. The reason this invention appears to be a ‘perpetual motion’ machine is, as others have already pointed out, the power output is miniscule. Should they make a breakthrough that allows generation on the milliamp or even amp scale, I’ve little doubt the device would rapidly go ‘flat’
Could be interesting. The level of output seems very small as to almost be a thermocouple effect from the dissimilar materials of the electrodes and nanowires coupled by the moisture in the air.
Logical. Change of state energy. So it seems to take the energy in the water moisture in the atmosphere to create energy, (moisture energy from when the water was evaporated by the sun), to a different moisture energy state. Is that as dew/water? What happens the water, does it create wet patches in clothing which need to dry out?
So does the energy come from the latent heat as the moisture condenses and turns into liquid ? If so then how is the liquid removed ? The article does mention “sustained voltage” which suggests it doesnt stop working at some equilibrium point.
Trevor’s description of a gradient driven effect for low power generation has a feel of correctness. I was thinking of the similar temperature gradient motivation in Crooke’s radiometer – which would be very difficult to scale up power rating.
It is not perpetual motion as the moisture is created by the suns energy evaporating water and the device must remove that energy from the moisture.
Perhaps this would be better as a pollution measuring instrument with a bit of tuning and tweaking.
~1285W/(m^3) … (assuming 14microns/layer)
Phone charging: 2-6 W
Cube side = 6.59in for 6W. So, roughly a half cinder block?
Not too shabby.
Potentially revolutionary technology that has to be tried and proven on a larger scale to be viable.
Airgen:
4mW/cm3 currently unoptimised, unindustrailsed
Halide-X 12 Offshore turbine (assume average 0.5m swept depth)
0.63mW/cm3
LM Wind 14,234 employees (2020), optimising wind turbine blades since 1978.
We have actually developed a Self-Charging Solid State Battery that uses humidity in the air to generate anomalous, continuous energy at room temperature. We are currently generating 0.5mA per cm2. We are looking for investors. We have built a portable 5KVA generator