We’re in that confusing time of year when it seems like temperatures have already peaked Descent into winter, suddenly they stand up again. This is of course in the northern hemisphere. In the south the opposite is the case. What is clear is that it is complicated Building with air conditioning. Air conditioning or heating? Hard decision. Whatever we choose, it is obvious that the energy expenditure, just like in the middle of summer or in the middle of winter, is enormous and the consumption of fossil fuels, a big problem. Therefore, a team of scientists from Harbin Engineering Institute in China, has designed an alternative inspired by the Chameleon skin.
Specifically, they decided to do so Namaqua chameleon (Chamaeleo namaquensis), an African species that has adapted very well to life in desert areas. He Desert It’s a pretty hostile place to live as temperatures can range from oppressively hot to freezing cold in the same day. Therefore, the animals and plants living there must have mechanisms that enable them to withstand them drastic temperature fluctuations. The authors of this study, just published in the Journal of the American Chemical Society, thought this would be a great source of inspiration for more efficient air conditioning in buildings, so they examined several types until they concluded that it This chameleon was the ideal.
It adapts to the temperature the way chameleons do best: Change color. If the environment is very warm, they become one light gray, This allows them to reflect heat. Just like when we paint a house white. However, when it gets cold, they turn darker. dark brown, which absorbs the greatest amount of heat possible and thus prevents freezing. All of this is known. In fact, there are already color-based inventions aimed at air conditioning in buildings. But no one had thought of changing the tone the way the chameleon does.
We look at the chameleon in the air conditioning of buildings
These scientists wanted to develop a paint capable of changing color like the chameleon does. To do this, they relied primarily on thermochromic microcapsules. Thermochromism is the ability of a substance to change color with changes in temperature. Like the typical cups in which a drawing is created when pouring a hot drink.
These microcapsules were combined with microparticles specialized in the production of paints and a binder that allowed the ingredients to mix well. So, a suspension which can be sprayed on like paint or applied with a brush. After making their paint to air-condition buildings, they spread it on a metal surface, which was then exposed to different temperatures. These came from 68, 86 and 175 degrees Fahrenheit Or what is the same, 20°C, 30°C and 79.44°C.
The color was initially dark gray, but became lighter as it warmed up, so that at 30 °C it already reflected 93% of the sun’s radiation. At 175°F it not only reflected radiation but There was no damage.
Even outdoors
After these experiments were conducted, a miniature building the size of the plein air painting was painted Doghouse. To compare the results, we also used a traditional white color, a paint specializing in passive radiant cooling, and some blue metallic tiles.
It was observed that their color warmed the house slightly more in winter than the radiant cooling color, even though the temperatures were very similar. In the summer it was significantly colder than white paint and metal tiles. But especially in spring and autumn Temperature fluctuations.
All of this would make it possible to air-condition buildings efficiently, cleanly and seemingly profitably all year round. We still need to do a little research, but maybe in the future our homes will be inspired by the skin of a chameleon. Of course, looking at nature is interesting for many reasons, not just to brighten our eyes.
