Water Vapor Holds Promise as New Clean Energy Source

Water vapor in the atmosphere could represent a new source of renewable energy, according to a study just published by researchers at Tel Aviv University.  The science behind this is similar to how lightning works, and the concept is very promising, albeit in the long run. 

Extracting Electricity from Water Vapor

The fact that electricity comes from water in the natural environment provides a nice head start, but the key is to actually harness this naturally-occurring energy source.  As noted in this article, lightning is created only by water in its different phases (vapor, droplets & ice).  But even though scientists understand the mechanics of lightning, there is no ability to harness it in any way.  Thus, this ability to “harness the chaos” is crucial. 

The researchers at Tel Aviv attempted to harness water vapor electricity via a very low-voltage battery, powered by nothing more than humidity.  The idea behind it is that the water droplets create friction on a metal surface within the battery, which then creates a charge, an effect discovered by English physicist Michael Faraday in the 1800s. 

The researchers found that voltage was generated once the relative humidity exceeded 60%.  Once generated, the electrical charges can then be transferred from one water molecule to another, like traversing a natural stone bridge going over a creek. 

Overall, this is good news considering that climates with relative humidity levels above 60% are not uncommon throughout the world.  That said, to produce enough water vapor electricity to power a home or community would require a battery the scope of which is not yet possible. 

For this reason, water vapor electricity is not going to be ready for prime time anytime soon – we’re talking years or decades before this technology proves viable.  But eventually the technology could hold real promise, especially in developing countries.