They generate electricity out of thin air – now the researchers are taking the next step

INNOVATION

The thin film collects water molecules from the air, the charge of which generates electricity. Now the researchers have sharpened the technology, and with enough layers they believe they can reach megawatts.

Bacteria found on the US East Coast were found to be able to create nanoscale protein threads that conduct electricity. Previously, researchers at the University of Massachusetts Amherst used the protein threads of the bacterium Geobacter sulfurreducens to create a thin film, and it generates electricity from the water vapor present in the air.

Any surface

The first test rig of the Air-gen produced a sustained 0.5 volts in the film, but now the researchers claim they can theoretically turn basically any surface into a generator – and they’ve published a new study on the technique in the scientific journal Advanced Materials.

The team has presented a new version of the thin film, and the key is the holes in the surface. Each pore is less than 100 nanometers, which is less than a thousandth of the thickness of a hair. The distance corresponds to the distance that a molecule can travel before it collides with another single molecule belonging to the same substance.

An imbalance is created

The collector consists of the film, which is bombarded from above with charged water molecules. They can get through the film, but because the pores are so narrow, the molecules hit the edge of the hole. The result is that many more molecules accumulate on the top side than make it through the holes to the encapsulated underside of the film – and that charge imbalance in itself constitutes a battery. The university writes this in a press release.

Air-gen generates electricity as long as there is moisture in the air, regardless of the time of day. And with such a thin material, you can scale up by simply adding more layers, without the facility requiring a larger area, according to the researchers. The researchers haven’t said how much energy their collectors generate, but with a thousand layers, they think it would be possible to get up to the megawatt scale.