Study: Butterfly posture raises efficiency of solar cells

Solar panels can capture the sun’s energy far more effectively if they were designed based on wing posture of the cabbage white butterfly.

A team of researchers at University of Exeter has discovered that by mimicking the v-shaped wing posture cabbage whites adopt to heat up their flight muscles before take-off, output from solar panels can be improved by almost 50 percent.

Also, by replicating the “wing-like” structure the overall power to weight ratio of the solar power systems can be increased 17-fold. In other words lighter panels can produce more power if they follow the wing-like design.

The team of researchers drawn from Environment and Sustainability Institute (ESI) and Centre for Ecology and Conservation of the university of Exeter’s Penryn Campus in Cornwall, has published its findings in Scientific Reports.

Cabbage whites have been observed to take flight earlier than other lepidopterans even on cloudy days.

Their ability to do so was linked to the v-shaped posturing, known as reflectance basking, these insects adopt on cloudy days to maximize the concentration of solar energy onto their thorax. It allows them take flight quicker than fellow butterfly species.

The wings of the cabbage whites have also been found to contain substructures that allow sunlight to be reflected most efficiently, thereby expediting the warming of their flight muscles.

The mono-layer of scale cells found in the butterfly wings if replicated in solar panels can vastly improve the power-to-weight ratios of future solar concentrators.

Based on this understanding the researchers have been studying lightweight reflective material that can be integrated with solar panels. They have also found that the optimal angle that maximizes capture of solar energy was about 17 degrees and temperature increased by 7.3C compared to when they are held flat.

Several new technologies have emerged by mimicking the ways of nature. Earlier, researchers in Japan had developed automotive paint that mimicked the properties of a butterfly wing and changed colour depending on the light shone on it.

Ajith Kumar S