Solar panel and biorefinery designers could learn from the efficiencies of iridescent giant clams, according to a study led by Yale University. These clams, found near tropical coral reefs, have a unique geometrical structure that may surpass existing solar panel technology in terms of solar energy conversion.
In the study, published in the journal PRX Energy, the researchers focus on the impressive solar energy potential of iridescent giant clams in the shallow waters of Palau in the Western Pacific. The clams are photosymbiotic, with vertical cylinders of single-celled algae growing on their surface. The algae absorb sunlight after it has been scattered by a layer of cells called iridocytes.
The arrangement of algae in vertical columns and the light-scattering properties of iridocytes are crucial factors. Light is filtered and scattered by iridocytes, then uniformly wraps around each vertical algae cylinder as it is parallel to incoming sunlight. This arrangement allows for the most efficient light absorption.
Based on this geometry, the researchers developed a model to calculate quantum efficiency, the ability to convert photons into electrons. Adding the clams’ ability to stretch and adjust their vertical columns to sunlight intensity further increased the quantum efficiency to 67%. This is significantly higher than the efficiency of a green leaf system in a similar tropical environment (14%).
Further comparisons could be drawn to boreal spruce forests, which have similar geometries and light-scattering mechanisms on a larger scale, according to the study. The researchers call for the preservation of biodiversity to continue studying and understanding efficient solar energy mechanisms found in nature.
The study’s insights could inspire new sustainable energy technologies, such as solar panels that grow algae or stretchable plastic solar panels mimicking the clams’ adaptable structure. The researchers emphasize that biodiversity plays an essential role in discovering innovative sustainable technologies. They also express gratitude to Palauans for their efforts to preserve these valuable ecosystems.
