Generating power from water droplets in the atmosphere may just become one of the most striking and promising discoveries of the year. In a study funded by the U.S. Department of Energy, the MIT researcher Nenad Milijkovic and team demonstrate that electric charge is detected as water droplets attached to superhydrophobic surfaces bounce away.
This discovery was made after a number of experiments with charged electrodes. The team discovered that when the droplets condense onto the positively charged surface, given that there are at least two droplets that can coalesce, these do a spontaneous jump, releasing energy. The team also performed the experiment with a negatively charged surface, noticing that the droplets are attracted to it, meaning that the release of energy occurs due to a net positive electrical charge formed during the jump.
The authors explain that the effect is due to a naturally formed electric double layer on the surface of the droplets. During the coalesce of two or more droplets, the charge separates, leaving some of it on the droplet, and the remaining charge on the surface.
If implemented in electricity-generating power plants, the finding of the research published in Nature Communications earlier this week, might significantly improve the efficiency of existing and future facilities by enhancing the ability of the condensers to attract the droplets. This could be done by integrating an external electric field, the authors claim.
In addition to this, Miljkovic and team believe that they can generate electricity from air. This will be made possible if the condenser surface is kept cool using the water of a natural water body. The authors are currently testing this by fitting paralleled metal plates in the open.