Wherever you are in the world, the sun rises in the east, moves up, over your head, then sets in the west. This means that the focal point of light is always moving and if light is your power source, then you might experience “oblique-incidence energy-density loss.”
To combat this issue, solar panels made from rows of tiny artificial sunflowers have been developed by researchers from the University of California Los Angeles and Arizona State University.
The “sunflowers” intuitively turn towards the light, allowing them to harvest solar power far more effectively than regular panels. This behavior mimics mother nature. It is the same process that real sunflowers employ – they tilt their flowers to face the sun, maximizing photosynthesis and heating their reproductive cells to attract pollinators.
This revolutionary system has seemingly limitless potential. It could provide a solution for almost any system that experiences efficiency loss due to a moving energy source. For example, with rays from an overhead illumination source, the light coming in at an angle of around 75 degrees carries up to 75% less energy.
Lead researcher, Ximin He, states that their system is a sunflower-like biomimetic omnidirectional tracker, dubbed ‘SunBOT.’
Every artificial sunflower has a stem made from a light-reactive material with an innovative energy harvesting flower, made from a similar material used in solar cells, sits on top of the stem. Each SunBOT is tiny and measure just 1 millimeter in diameter.
When an area of the SunBOT’s stem receives light exposure, it heats and then shrinks, causing it to lean towards the light. Once aligned with the light, the SunBot stops bending as flower starts to create a shadow, giving the materials time to cool and stop shrinking.
The team built a panel of SunBots to test its energy harvesting capabilities. The board was part made up of the bendy material and part made of material that didn’t bend. The researchers found that the SunBOTs with the bendy-stems were able to harvest up to 400% more solar energy than their non-bendy counterparts.
SunBOTs’ creators explain:
“This work may be useful for enhanced solar harvesters, adaptive signal receivers, smart windows, self-contained robotics, solar sails for spaceships, guided surgery, self-regulating optical devices, and intelligent energy generation, as well as energetic emission detection and tracking with telescopes, radars, and hydrophones.”
The possibilities really could be endless with this innovative new kind of technology! The researchers detail their study in Nature Nanotechnology.
