Skip to content
thunderstorm with dark clouds
Photo by Josep Castells. The BFD

For the last century, Jeremiahs have been predicting that the world will imminently run out of oil. So-called “Peak Oil” has enjoyed one of its perennial revivals in tandem with Climate Change hysteria, but the idea that we must immediately drop fossil fuels because they’re on the brink of depletion is no less ludicrous than it was in 1909.

There’s an old saying that “The Stone Age didn’t end for lack of stones: the Oil and Coal Age will end long before we run out of oil.”

Make no mistake: fossil fuels will be replaced. Not because governments force us to change, but because a better alternative will come along. We’re not there yet, though: don’t believe the “renewables” and “Net Zero” hype; there is no feasible replacement for oil and coal at hand.

What the replacement technology will be, no one yet knows. It will very likely be something as novel and unexpected as the internal combustion engine was in the late 19th century, or nuclear power in the 1940s.

Possibly something like this:

A team of engineers at the University of Massachusetts Amherst has recently shown that nearly any material can be turned into a device that continuously harvests electricity from humidity in the air. The secret lies in being able to pepper the material with nanopores less than 100 nanometers in diameter. The research appeared in the journal Advanced Materials.

“This is very exciting,” says Xiaomeng Liu, a graduate student in electrical and computer engineering in UMass Amherst’s College of Engineering and the paper’s lead author. “We are opening up a wide door for harvesting clean electricity from thin air.”

If the idea of electricity from air seems implausible, you must never have seen a lighting bolt.

“The air contains an enormous amount of electricity,” says Jun Yao, assistant professor of electrical and computer engineering in the College of Engineering at UMass Amherst, and the paper’s senior author. “Think of a cloud, which is nothing more than a mass of water droplets. Each of those droplets contains a charge, and when conditions are right, the cloud can produce a lightning bolt – but we don’t know how to reliably capture electricity from lightning. What we’ve done is to create a human-built, small-scale cloud that produces electricity for us predictably and continuously so that we can harvest it.”

What is the nature of this “small-scale cloud”?

The heart of the man-made cloud depends on what Yao and his colleagues call the “generic Air-gen effect”, and it builds on work that Yao and co-author Derek Lovley, Distinguished Professor of Microbiology at UMass Amherst, had previously completed in 2020 showing that electricity could be continuously harvested from the air using a specialized material made of protein nanowires grown from the bacterium Geobacter sulfurreducens.

“What we realized after making the Geobacter discovery”, says Yao, “is that the ability to generate electricity from the air – what we then called the ‘Air-gen effect’ – turns out to be generic: literally any kind of material can harvest electricity from air, as long as it has a certain property.”

That particular property is holes. Small ones. Very, very small ones.

“It needs to have holes smaller than 100 nanometers (nm), or less than a thousandth of the width of a human hair.”

This is because of a parameter known as the “mean free path,” the distance a single molecule of a substance, in this case water in the air, travels before it bumps into another single molecule of the same substance. When water molecules are suspended in the air, their mean free path is about 100 nm.

As you were probably taught in school science, lightning is the result of countless molecules in the air rubbing against each other, generating static electricity like a pair of plastic soles shuffled across a wool carpet.

The “electricity harvester” is made from a thin layer of material peppered with 100 nm pores. Water molecules passing through the pores create an imbalance of charged particles on either side of the material.

All you need is humidity and, presto! You have a battery. Given that humidity is ominipresent, it doesn’t rely on the sun shining or the wind blowing.

Finally, because air humidity diffuses in three-dimensional space and the thickness of the Air-gen device is only a fraction of the width of a human hair, many thousands of them can be stacked on top of each other, efficiently scaling up the amount of energy without increasing the footprint of the device. Such an Air-gen device would be capable of delivering kilowatt-level power for general electrical utility usage.

“Imagine a future world in which clean electricity is available anywhere you go,” says Yao.

University of Massachussetts Amherst

Too good to be true? Quite possibly, and if it sounds too good to be true… And never forget the hoopla over “cold fusion”. So, I won’t be holding my breath on this one, just yet.

Still, just recall that who, after all, could have envisaged the nuclear reactor when Peak Oil was first predicted in 1909?

Latest