Powering homes with electricity collected from air may soon be possible
By ANIThursday, August 26, 2010
WASHINGTON - Electricity collected from the air could become the newest alternative energy source, say scientists, who have solved a 200-year-old scientific riddle about how moisture in the atmosphere becomes electrically charged.
“Our research could pave the way for turning electricity from the atmosphere into an alternative energy source for the future,” said study leader Fernando Galembeck.
He is with the University of Campinas in Campinas, SP, Brazil.
“Just as solar energy could free some households from paying electric bills, this promising new energy source could have a similar effect.
“If we know how electricity builds up and spreads in the atmosphere, we can also prevent death and damage caused by lightning strikes,” Galembeck said, noting that lightning causes thousands of deaths and injuries worldwide and millions of dollars in property damage.
The notion of harnessing the power of electricity formed naturally has tantalized scientists for centuries. They noticed that sparks of static electricity formed as steam escaped from boilers. Workers who touched the steam even got painful electrical shocks. Famed inventor Nikola Tesla, for example, was among those who dreamed of capturing and using electricity from the air.
It’s the electricity formed, for instance, when water vapor collects on microscopic particles of dust and other material in the air.
But until now, scientists lacked adequate knowledge about the processes involved in formation and release of electricity from water in the atmosphere, Galembeck said. He is with the University of Campinas in Campinas, SP, Brazil.
Scientists once believed that water droplets in the atmosphere were electrically neutral, and remained so even after coming into contact with the electrical charges on dust particles and droplets of other liquids. But new evidence suggested that water in the atmosphere really does pick up an electrical charge.
Galembeck and colleagues confirmed that idea, using laboratory experiments that simulated water’s contact with dust particles in the air.
They used tiny particles of silica and aluminum phosphate, both common airborne substances, showing that silica became more negatively charged in the presence of high humidity and aluminum phosphate became more positively charged.
High humidity means high levels of water vapor in the air, the vapor that condenses and becomes visible as “fog” on windows of air-conditioned cars and buildings on steamy summer days.
“This was clear evidence that water in the atmosphere can accumulate electrical charges and transfer them to other materials it comes into contact with,” Galembeck explained. “We are calling this ‘hygroelectricity,’ meaning ‘humidity electricity’.”
In the future, he added, it may be possible to develop collectors, similar to the solar cells that collect the sunlight to produce electricity, to capture hygroelectricity and route it to homes and businesses.
Just as solar cells work best in sunny areas of the world, hygroelectrical panels would work more efficiently in areas with high humidity.
The research has been presented at the 240th National Meeting of the American Chemical Society (ACS). (ANI)