In the blistering heat of the desert, camels have evolved a unique method to stay calm and retain moisture: a thick layer of insulating hair.

Researchers at the Massachusetts Institute of Technology (MIT) have created a double-layered material inspired by this natural mechanism.

It mimics the camel's cooling effect, providing a constant cooling solution for preserving perishable goods without a power source.

Contrary to what one might think, wearing a camel's hair coat on a hot day is not as crazy as it sounds.

Many desert residents don thick coats for the same reason – to minimize moisture loss while allowing sweat to evaporate and create a cooling effect. Tests reveal that shaved camels lose 50% more water than those with their natural coat.

MIT's innovative system employs a two-layer material to replicate this cooling effect. The bottom layer comprises a hydrogel acting like sweat glands. Hydrogel, a water-based gel, features a spongy matrix structure facilitating easy water evaporation.

This layer is then covered with aerogel, functioning like fur, blocking external heat while allowing vapour passage. Despite being less than half an inch thick, this double-layered material can achieve over 7 degrees Celsius of cooling – more than the hydrogel alone and lasting five times as long.

The applications of this system are promising. It can be used in food packaging, providing farmers with more options for selling perishable crops.

It could also safely transport medicines like vaccines over long distances. Unlike traditional refrigeration methods, this passive system relies solely on heat, reducing temperature fluctuations and preventing rapid spoilage.

Researchers suggest this packaging could offer long-lasting protection for perishable items from farms or factories through the supply chain to consumers' homes. This is a notable improvement over current systems relying on refrigerated transport, where temperature spikes can occur during loading and unloading.

The raw materials used in this two-layer system are relatively inexpensive. Aerogel, derived from silica found in beach sand, is abundant and cheap.

However, scaling up the system requires further research due to the large and expensive processing equipment. Nonetheless, some start-up companies are already exploring using this material for insulated windows.

The underlying principle of water evaporation has been used for centuries to create cooling effects.

However, incorporating an insulating layer inspired by camels into artificial cooling systems is a novel approach.

For specific applications like food packaging, transparency of hydrogel and aerogel materials is crucial. However, opaque insulation can be employed for uses such as pharmaceuticals or space cooling.

Hydrogel materials, composed of 97% water, undergo evaporation. In an experiment, a 5 mm layer of hydrogel covered with 5 mm of aerogel took 200 hours to evaporate, compared to 40 hours with hydrogel alone wholly.

Although the two-layer material had a slightly lower cooling capacity, it offered a longer-lasting effect. Once the water evaporates, the material can be recycled by refilling it.

This material has significant potential in developing countries with limited electricity supply, offering an electricity-independent solution for preserving perishable items throughout storage and distribution.