Posted on February 26, 2020
Can you imagine a device that produces electricity from nothing, 24 hours a day, 7 days a week?
Electrical engineer Jun Yao and microbiologist Derek Lovley, both of the University of Massachusets Amherst (USA), have created a device called 'Air-gen' or air-powered generator that uses a natural protein to generate electricity from just the humidity of the air.
This air generator connects electrodes to the protein nanowires (just 7 microns thick, one-tenth of a human hair), generating electric current from the water vapour present in the atmosphere.
To be more specific, these nanowires are made of electrically conductive proteins produced by the microbe Geobacter sulfurreducens.
Similar experiments have been carried out in the past using nanomaterials such as graphene, but they only produced intermittent and short bursts of electricity, instead of a "continuous voltage output" such as that achieved by the Air-gen system and explained in the scientific journal 'Nature'.
Air-gen produces a sustained voltage of 0.5 volts at 17 microamps per square centimetre, that is actually very little power, since you would need several Air-gen devices connected to each other to charge your smartphone.
However, the team of researchers is looking to scale it to industrial-sized systems as soon as possible, given that the system does not produce polluting waste and could work in extreme weather conditions.
A problem is the limited amount of protein nanowire that can currently be produced by the Geobacter sulfurreducens microbe, although the possibility of genetically designing another microbe, E.coli, to mass produce the nanowire is being considered. With this new scalable process, the supply of protein nanowires would no longer be a bottleneck in the development of these applications. The future is here!!