Photo taken by Camille Flammarion in 1902 of lightning striking the Eiffel Tower on a summer night.
Positively Charged Humidity
“Nikola Tesla would be jealous. A group of chemists from Brazil have presented research claiming they’ve figured out how electricity is formed and released in the atmosphere. Based on this knowledge, the team said it believes a device could be developed for extracting electrical charges from the atmosphere and using it for electricity. They found that silica becomes more negatively charged when high levels of water vapor are present in the air, in other words during high humidity. They also found that aluminum phosphate becomes more positively charged in high humidity. “This was clear evidence that water in the atmosphere can accumulate electrical charges and transfer them to other materials it comes into contact with. We are calling this ‘hygroelectricity,’ meaning ‘humidity electricity,'” Galembeck said in a statement. But the discovery, if true, goes against the commonly held theory among scientists that water is electroneutral–that it cannot store a charge. Galembeck does not dispute the principle of electroneutrality in theory, but believes real-life substances like water have ion imbalances that can allow it to produce a charge.”
“My colleagues and I found that common metals—aluminum, stainless steel and others—acquire charge when they are electrically isolated and exposed to humid air,” he says. “This is an extension to previously published results showing that insulators acquire charge under humid air. Thus, air is a charge reservoir.” The finding would seem to confirm anecdotes from the 19th century of workers literally shocked—rather than scalded—by steam. And it might explain how enough charge builds up for lightning, Galembeck argues. The scientists envision devices to harness this charge out of thick (with water vapor) air—a metal piece, like a lightning rod, connected to one pole of a capacitor, a device for separating and storing electric charge. The other pole of the capacitor is grounded. Expose the metal to high humidity (perhaps within a shielded box) and harvest voltage.”
“In 1840, workers in Newcastle upon Tyne, UK, reported painful electric shocks when they came into close contact with steam leaking from factory boilers. Both Michael Faraday and Alessandro Volta puzzled over the mysterious phenomenon, dubbed steam electricity, but it was ultimately forgotten without being fully understood. Fernando Galembeck thinks there is a simple explanation, but it involves accepting that water can store charge – a controversial idea that violates the principle of electroneutrality. This principle – which states that the negatively and positively charged particles in an electrolyte cancel each other out – is widely accepted by chemists. His team electrically isolated chrome-plated brass tubes and then increased the humidity of the surrounding atmosphere. Once the relative humidity reached 90 per cent, the uncharged tube gained a small but detectable negative charge of 300 microcoulombs per square metre – equating to a capacity millions of times smaller than that of an AA battery. The Victorian workers would have had to have been particularly sensitive souls to complain of such a shock, but Galembeck thinks his study shows steam electricity may be a credible phenomenon. He thinks the charge builds up because of a reaction between the chrome oxide layer that forms on the surface of the tube and the water in the atmosphere. As the relative humidity rises, more water condenses onto the tube’s surface. Hydrogen ions in the water react with the chrome oxide, leading to an ion imbalance that imparts excess charge onto the isolated metal.
The work finds favour with Gerald Pollack at the University of Washington in Seattle. Last year he suggested that pure water could store charge and behave much like a battery, after finding that passing a current between two submerged electrodes created a pH gradient in the water that persisted for an hour once the current had been switched off. He says this is evidence that the water stores areas of positive and negative charge, but the experiment led to a lively debate in the pages of the journal Langmuir over whether the results really violated the principle of electroneutrality or whether there were salt impurities in the water that led it to behave like a conventional electrochemical cell.”
“Pollack’s water studies have led to amazing possibilities: that water acts as a battery, that this battery may recharge in a way resembling photosynthesis, that these water batteries could be harnessed to produce electricity. “Some findings seemed to imply that water acted as though it was a polymer; in other words, all the molecules would somehow join together into a polymer and create some really weird kinds of effects,” Pollack described. Eventually, these results – first presented by a Russian chemist – were discredited. “The nails were driven into the coffin of water research by another debacle that took place 20 years later, and that was the idea of water memory,” Pollack said. “The idea was that water molecules could have memory of other substances into which it had been in contact. It’s a 100-year-old idea that there’s a fourth phase of water. This is not an original idea.” Though the concept of a liquid crystalline, or gel-like, phase of water has been around for some time, the generally accepted view is that this kind of water is only two or three molecular layers thick. “And what we found in our experiments is that it’s not two or three layers, but two or three million layers. In other words, it’s the dominant feature,” Pollack said. He has since discovered much about its underestimated thickness, its capacity to create a charge, its connections to photosynthesis and its practical applications. The thickness of this gel-like water may explain why items of higher density than water – such as a coin – can float. Surface tension is at work, but it arises from this thick, gel-like surface layer. “Turns out that the thickness depends on the pH,” Pollack said. “If you increase the pH, we found that this region gets thicker. It also gets thicker with time.
Dr. Pollack works in his lab to demonstrate some of the unusual properties of water. “This kind of water is negative, and the water beyond is positive. Negative, positive – you have a battery,” Pollack explained. “The question is, how is it used and might we capitalize on this kind of battery?” The key to understanding how this water battery works is learning how it is recharged. “You can’t just get something for nothing – there has to be energy that charges it,” Pollack said. “This puzzled us for several years, and finally we found the answer: it’s light. It was a real surprise. So if you take one of these surfaces next to water, and you see the battery right next to it, and you shine light on it, the battery gets stronger. It’s a very powerful effect.””