Solar panel technology has plenty of room for improvement, especially in the efficiency category. While they're fantastic in terms of green energy, they can definitely be more efficient when it comes to how much light they absorb, and how long they hold onto that energy. We’ve seen them becoming more adaptive to the environment, such as thin-film solar cells, but that hasn't been without setback. Interestingly, butterfly wing-inspired design could provide the best way yet to generate solar power via panels.
Researchers from the California Institute of Technology and the Karlsruhe Institute of Technology have looking into how to improve thin solar cells. While efficiency has been sacrificed, they have benefits in all the other categories when compared to traditional solar cells. They have the ability to adapt onto any surface, they’re lighter, and often cheaper to produce.
Inspiration for a butterfly model came from the rose butterfly often found in India. Its black wings have the ability to warm itself in colder areas. Looking at the insect further, they discovered that the wings had little holes. This made the wings lighter for the insect and sunlight was able to be absorbed quicker since it was scattered through the holes.
Taking this further, CIT bioengineer Radwanul Siddique looked at computer models showcasing how this feature would work with solar panels. Holes on the butterfly differed in every aspect, such as how many there were, their size, and how they were shaped along the wings. The team determined that shape didn’t matter, but where they were located and how many there were was important.
“I think what’s interesting is the excellent approach of looking at the underlying physiological concepts and then taking these concepts and emulating them in a structure that doesn’t look quite look like how a butterfly looks but does the same physics,” Mathias Kolle told The Verge. Kolle, an engineering professor at the Massachusetts Institute of Technology, wasn’t a part of the research, but knew the benefits of the process.
They were able to easily convert the setup to multiple layers of hydrogenated amorphous silicon sheets. Amorphous silicon is the semiconductor frequently used in thin-film solar cells and they are environmentally friendly to produce when compared to the alternatives. Again, the shapes of the holes didn’t matter, but they put them in specific locations. The process only takes up to 10 minutes.
Test results were very positive, absorbing twice as much light when compared to other thin-film solar cells. According to Phys.org, rates saw an “increase of 90 percent at a normal incident angle of light to as high as 200 percent at large incident angles.” It’s a tremendous step for the solar technology as low efficiency, the biggest drawback, is being thwarted.