Scientists have learned from the camel about how to keep things cool. They’ve developed a product which can keep objects such as shipping containers at 7°C below the ambient temperature without electrical power. It all happens naturally and is based upon the way camels survive in harsh, high temperature conditions.
The technology is in the form of a pliable material which is about 1 cm thick. There are two layers: a 5 mm layer of hydrogel which is a substance that acts as a reservoir of water and a 5 mm layer of aerogel which acts like a camel’s fur. The aerogel or artificial fur acts as an insulator, a barrier to the heat while allowing water vapour from the hydrogel to evaporate. The cooling process comes from the latent heat of evaporation which is heat being removed from an object in the evaporating water vapour.
The hydrogel is a substitute for the camel’s sweat glands while the aerogel in substitute for the camel’s fur, as mentioned. They found that the technology can be effective for 200 hours before the water in the hydrogel has fully evaporated and needs to be recharged with water. Without the aerogel, water is depleted in 40 hours. The scientists believe that it could be used to transport and temporarily store perishable products without the need for conventional refrigeration. They see the technology being useful in places where the supply of electricity is unreliable or scarce such as in developing countries.
It may also assist in keeping the interior of buildings cooler in hot climates. I believe that they are thinking about a form of cladding but one of course which is safe (c.f. the the Grenfell fire cladding which was highly unsafe). They also believe that it might assist in combating climate change as providing power to buildings to cool them down through air conditioning or heat them up through natural gas boilers contributes to global warming. Buildings are responsible for more than a quarter of global CO2 emissions.
The science is published in the journal Joule.