“Air-gen Technology: Harnessing Electricity from Water Vapor”

Here we have another experimental technology for the production of electricity from renewable sources. This time, water vapor with an electrical charge replaces the sun, wind or even gravity.

Even the seemingly driest air in the middle of Death Valley is still saturated with water vapor. At six o’clock this morning, it was doing some 31 percent relative humidity in the form of microscopic water droplets. And these droplets are the carrier of the electric charge, which is then discharged during a summer storm.

The lightning rod discharges the energy of the electrostatic discharge into the ground, so we don’t really get anything out of it. Engineers are therefore looking for a way to store this energy

Of course, scientists have been looking for a way to efficiently harness the tremendous energy of such an electrostatic discharge for years capture and save – one single atmospheric lightning on average carries up to GJ units (superblesky even >100 GJ).

But they also deal with the question of whether it would be possible to create an analogy charged cloud on a miniature and low-voltage scale, for example in the form of a battery cell.

Membrane batteries surrounded by air

Engineers from the University of Massachusetts in Amherst took this path years ago, who first joined the game in 2020 special proteinto show off this May the universal way for almost any material.

The basic principle of their battery is actually quite simple. Imagine a porous membrane filled with tiny holes 100 nanometers in size. This corresponds roughly to the average distance before a water molecule in the air collides with another H₂O molecule.

A membrane with 100nm holes in which microscopic water droplets with an electric charge are captured. In the upper part, more of them are bought, there is a difference in the electric charge and thus also the electric voltage on the electrodes

What is important to us is that the water molecules in the naturally saturated air will hit this membrane, with some entering the holes through which they pass deep into the medium.

So far, only titrated electrical voltage and current

The molecules have an electrical charge that they pass on to the membrane, and since only a few pass through the holes when bombarding the top side, more are bought there.

Electrical properties of the membrane after connecting to the circuit

As a result, a collective charge is slowly built up on the upper side, which is greater than on the lower side, and when we connect electrodes to these surfaces, we measure a tiny electric voltage in the order of tens of mV. By connecting it to a circuit with a consumer, we can then discharge the charge as a titer flowing electric current in the order of nA units.

It is still far from a practical battery

The authors of the study, which they recently published in the journal Advanced Materialsthey called their technology generic air-gen effect and they will further develop and research it.

From a membrane with a tiny natural charge obtained from ambient air humidity to a battery that could one day compete with at least other renewable energy sources, there is still a long and difficult journey with an uncertain result.