Researchers from Tel Aviv University have discovered that humidity in air has potential to become a source of renewable energy. The team successfully generated a voltage using only water and metal in their laboratory experiments.
Although energy generated is very small, but if they raise the stakes, the technique could be used to charge batteries.
Prof. Colin Price, co-author of a paper, said, “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,”
Natural phenomenon behind why lightning occurs in nature
Science behind this discovery is the fact that electricity materializes in the interaction between water molecules and metal surfaces.
Price explained, “Electricity in thunderstorms is generated only by water in its different phases — water vapor, water droplets, and ice. Twenty minutes of cloud development is how we get from water droplets to huge electric discharges — lightning — some half a mile in length,”
Researchers used the scientific discovery that ‘water droplets in air could charge metal surfaces’ as the basis of their research. So they worked on this phenomenon and found that voltage only developed when relative humidity in air is above 60%. This atmospheric condition is extremely common in most tropical countries.
Scientists foresee that the charge generated in this way could be used as a green energy source in long run.
Prof. Price said, “The results may be particularly important as a renewable source of energy in developing countries, where many communities still do not have access to electricity, but the humidity is constantly about 60%,”