So a few years ago, when I was starting out on my PDE career, my granny sent me an article about a girl my age who had designed a sustainable refrigerator for the developing world. I remember being impressed with the design, then feeling slightly dispirited when comparing my achievements to hers, before I stuffed it away into a box of miscellaneous items. But I did keep it. And now it seems that concept is rather fitting with my design and technology assignment. Thanks granny!
Emily Cummins’ cylindrical fridge is powered by the sun, but not in the way you might think. There are no photovoltaic cells, just two metallic cylinders, one inside the other, encasing tightly packed material, soaked in dirty water. The sun heats the wet material, and water evaporates off, removing heat from the inner chamber. Meat and milk can be kept cool (6°C) for days, and re-soaking with water gives the product an infinite lifetime. This method was actually learnt from the locals, although they had been using pots that were much less efficient and hygienic.
A few years on, and the product is being used by thousands in rural African communities, who can now keep their food fresh and safe. Emily has sold the design plans for the fridge, meaning as many people as possible can experience the benefits. People can build their own using any kind of solid material for the outer cylinder (e.g. barrels, pipe) and a local material (e.g. sand or wool), as long as they can source a watertight metallic cylinder such as a pot or pan.
This concept goes to show what we can learn from communities who exist without the need for technology. They may not have the design skills or materials to construct the most efficient product, but they can invent methods using nature as their technology. If we can help to build upon their quality of life, while learning from them about nature’s abilities, it is surely a win-win situation.