By Duncan Geere, Wired UK

Move over solar, wind and wave power – there's a new renewable on the block. Researchers are experimenting with devices that can pull electricity from the air.

For centuries, scientists have been fascinated by the idea of harnessing the power of thunderstorms. Nikola Tesla experimented extensively with the topic, but significant understanding of the field of atmospheric electrodynamics has until recently proved elusive.

Fernando Galembeck, of the University of Campinas in Brazil, presented a report at the 240th National Meeting of the American Chemical Society that detailed a future where every house has a device on its roof that pulls cheap, clean electricity out of the air. "Just as solar energy could free some households from paying electric bills, this promising new energy source could have a similar effect," he said.

Originally, scientists believed that water droplets in the atmosphere were electrically neutral, and remained that way even after brushing up against charges on dust particles and other liquids. However, Galembeck discovered in a series of lab experiments that water droplets do in fact pick up a charge.

He used particles of silica and aluminum phosphate, both of which are common dust particles in the air, and found that they become increasingly charged as the amount of water vapor in the air increases. "This was clear evidence that water in the atmosphere can accumulate electrical charges and transfer them to other materials it comes into contact with," said Galembeck.

It could be possible to harvest this "hygroelectricity" from the air in regions that experience high humidity, such as the tropics. To jump-start this industry, Galembeck's team is already testing metals to see which might be of most use in capturing atmospheric electricity on hygroelectric panels.

A similar approach could help to avert lightning damage, too, by placing hygroelectric panels on buildings to take charge out of the air in the vicinity of places that suffer regular thunderstorms. "These are fascinating ideas that new studies by ourselves and by other scientific teams suggest are now possible," said Galembeck.

"We certainly have a long way to go. But the benefits in the long range of harnessing hygroelectricity could be substantial."

Image: Flickr/Bobby Dimitrov.

See Also: