MIT Material Can Keep Perishable Goods Cool Without Requiring Power
MIT researchers have developed a new material inspired by camel fur made from two layers that can keep perishable goods cool without needing any power. The two-layer passive cooling system is made of hydrogel and aerogel. Researchers say that it can be used to keep foods or pharmaceutical cool for days without needing electricity.The material can be seen in the photo above, its top layer is aerogel, and the bottom layer is a hydrogel. Material is inspired by camel fur, which helps keep the animals cool and helps them to conserve water in the scorching desert environment. It seems counterintuitive that a thick coat of fur would help camels to stay cool, but tests have shown that a shaved camel loses 50 percent more moisture than an unshaved one under ideal conditions.
The bottom layer of MIT's material is a substitute for sweat glands made of hydrogel. This gelatin-like substance is mostly water contained in a sponge-like matrix that allows the water to evaporate easily. The upper aerogel layer plays the part of the fur, keeping out external heat while allowing the vapor to pass through. Hydrogels have been used for cooling applications in the past. Field tests have found that MIT's material can provide cooling of more than seven degrees Celsius for five times longer than hydrogel alone despite being less than half an inch thick.
That means the material can work for more than eight days compared to only two days for other materials. Researchers believe the system can be used for food packaging to help preserve freshness and expand distribution options for perishable crops. The cooling device could also help keep vaccines safe as they're delivered to remote locations. Existing systems for cooling perishable crops and vaccines require refrigerated trucks or storage facilities with cooling systems.
Temperature spikes between the refrigerated systems help to increase spoilage. The raw materials used to make the cooling device are inexpensive. The primary material, aerogel,l is made of silica, basically beach sand. The only downside is processing equipment to make aerogel is large and expensive, but companies are working on large-scale processing to make the material.