This fuel new engine isn’t going to start replacing anything anytime soon, but at its cheap price point—it only costs $5 to make—it’s a stepping stone towards greener energies with engines running on nothing more than water and bacterial spores.
Last Tuesday, researchers from the University of Columbia published a research in Nature Communications that presented devices powered by nothing more than the swelling and shrinking of bacteria spores. These spores worked by changes in humidity. While the prototypes look simple, the researchers are sure that they’ve hit something revolutionary.
This research is nearly a decade old and started when Ozgur Sahin, lead author and associate professor, was involved in a study about bacterial spores.
According to Sahin, “People before us had shown that the spores change shape in response to humidity.” “They shrink when they’re dry and expand when exposed to moisture. But in our studies, we found them to be surprisingly rigid. That told us that this shape change must come with a lot of energy. In the beginning, I was just amazed at this biological substance. But then I thought, there must be applications for this.”
“I sketched out this idea, where a device was placed on the surface of a reservoir of water,” he said. “If you made shutters that could allow moisture through or block it, you could control the humidity of the spores inside, making them cyclically expand and contract.”