Wind energy already yields four percent of Earth’s power, but five researchers at French institutions recently drew inspiration from nature to make wind turbines even better. Inspired by creatures like dragonflies, they found flexible blades on wind turbines make the machines much more efficient. Wind turbines today work best under optimal wind speeds, but the new bio-inspired design could offer a way around that fact, making wind power even more accessible.
Wind speeds impact the functioning of a wind turbine. If the wind is too slow, the turbine won’t turn and generate energy; if the wind is too fast it could damage the turbine. Wind also must hit the turbines at the correct pitch angle to apply the correct amount of torque to the generator, according to Science. The new research from scientists at Sorbonne University and École Nationale Supérieure des Arts et Métiers-ParisTech fixes these issues with flexible blades much like insect wings.
The researchers constructed prototypes with regular hard turbine blades, slightly flexible turbine blades, and very flexible turbine blades. The last design turned out to be too floppy, but the slightly flexible blades outperformed the rigid ones, offering as much as 35 percent more power. They also continued to work in lower wind conditions and weren’t as susceptible to damage in high winds.
The journal Proceedings of the Royal Society A published the research online in February. But the scientists’ work isn’t yet done: they now need to search for the right material that’s “flexible, but not too flexible,” according to lead author Vincent Cognet, to scale up the findings.
Engineer Asfaw Beyene of San Diego State University, who was not part of this study, told Science, “The fluid mechanics and the physics make absolute sense. There’s no reason why we cannot make morphing blades that will adapt to wind conditions.”