NEWS FROM THE WORLD OF THE ENVIRONMENT
Solar powered wasps
December 16, 2010
An article was published in the German scientific journal Naturwissenschaftenna about a study carried out by a team of Israeli researchers from the University of Tel-Aviv which highlighted how Vespa orientalis (originally from eastern countries but which is also found in southern Italy) has a particular structure in the abdomen which would be able to capture solar radiation and transform it into energy.
The study was born observing the fact that these insects were more active during the hottest hours of the day, contrary to what happens in similar animals. From here, using special microscopes, it was possible to analyze the different structures that make up the cuticle of these wasps ( their skin, to understand).
It has been seen that the yellow colored part of the abdomen is formed by several protuberances (50 nanometers2 high) intertwined, elliptical in shape with each inside a small depression. These particular structures would trap the light (thus carrying out an anti-reflective action) which would be accumulated to produce energy. In practice, to put it in simpler words, this wasp carries a real photovoltaic panel. The other way around the brown colored part is formed by numerous grooves 160 nanometers2 high which would have the task of facilitating / directing the light towards the yellow part.
The search did not end there. In fact, from increasingly in-depth analyzes it has been observed that the cuticle in the innermost part is formed by a set of chitin3 layers that filter the light towards a particular pigment, responsible for the extraction of energy from the rays of the sun: the xantopterin which in practice plays the delicate function of transforming light into electrical energy.
Ultimately from the study of the biocuticle of an insect it was highlighted that xantopterins could act as a light absorbing material in photovoltaic devices and to demonstrate their theory, the researchers created a small solar cell based on the same principle, managing to obtain the conversion of light into electricity, with a fairly low yield for the moment, but in any case worthy of note that opens up interesting prospects for the future.
Note(1) Image not subject to copyright
(2) 1 nanometer = 1 millionth of a millimeter
(3) Organic substance, nitrogenous polysaccharide, very resistant to chemical agents, which constitutes the external skeleton of arthropods, the cuticular coatings of other invertebrates, and the membranes of many fungi, lichens, bacteria (from Encyclopedia Treccani).