Bacterial spores that live off evaporation inspire clean energy source

About 1,000 trillion liters of water are evaporated every day on Earth, and millions of bacterial spores respond to this process daily. This process can now be a source of clean energy thanks to researchers at Columbia University. The technology is inspired by the property of bacterial spores, which can swell and contract in response to changes in humidity. Ozgur Sahin and his team at Columbia were intrigued by this movement and concluded that it must come with a lot of energy, so they wanted to make use of it. Therefore, they glued billions of these spores together on plastic tape, resulting in the following $5 design:

bacspores Bacterial spores that live off evaporation inspire clean energy source News

This technology is not as efficient as solar cells when capturing the sun’s power; but it could be hundreds of times cheaper to build per unit area, which makes it attractive for scaling up rapidly. The devices are already able to to turn on light bulbs, so Sahin thinks that the technology could be used to power lights on devices that sit on the sea— hydrothermal generators or oil rigs, for example. However, Peter Fratzl, a biomaterial researcher at the Max Planck Institute of Colloids and Interfaces, believes it will not revolutionize transport or other high-power applications. Nonetheless, it could provide the small power needed in remote places to operate communication devices in a very affordable and innovative way.



Rathi, A. (2015, June 16). These machines can capture a new source of clean energy—evaporating water. Quartz. Retrieved from:

Feltman, R. (2015, June 16). This engine uses nothing but water and bacteria to power small devices. The Washington Post. Retrieved from: