Tel Aviv University researchers are confident that they’ve found a way to turn water vapor in the air into a practical source of renewable energy.
Their discoveries are based on the natural phenomenon of lightning, as Colin Price, one of the researchers at the University’s Porter School of the Environment and Earth Sciences, explains:
“Electricity in thunderstorms is generated only by water in its different phases — water vapor, water droplets, and ice,” Price said.
“Twenty minutes of cloud development is how we get from water droplets to huge electric discharges – lightning – some half a mile in length.”
It’s been known for centuries that airborne water droplets can charge metal surfaces. That during molecular collisions, electrical charges are exchanged and that friction can cause a type of static electricity.
Humidity key to producing power from water vapor
What the Tel Aviv researchers found is that enough power was only produced once relative humidity in the air rose above 60 percent. They subsequently worked out that materials such as zinc and stainless steel are able to receive a charge of roughly one volt.
There are several regions in the world where the humidity levels would be high enough to generate electricity and the scientists hope that this could one day provide a positive impact for some developing countries where residents remain without access to power.
Up until now the researchers have only been able to produce small amounts of electricity. But there is hope that it can be scaled up to perform a function such as charging a battery.
“If an AA battery is 1.5V, there may be a practical application in the future: to develop batteries that can be charged from water vapor in the air,” said Price.