It is this kind of truly remarkable invention can (and did) get a student designer like Emily Cummins an invitation to visit with the Queen of England. It looks like an unassuming mixed-material cylinder, but conceals the astonishing ability to transform rays from the sun into vital food-cooling air … a simple but world-changing technology.
Refrigeration is a tough technology to make mobile, let alone solar-powered and suitable for the developed and developing nations of the world alike. A few years, now, since its creation, and already this little fridge has changed the lives of thousands of rural Africans who have heretofore relied on less convenient, cheap and healthy methods for keeping edible commodities fresh and safe.
Better than the best cold basement, this device is capable of keeping milk and meat cool for days in most climates – not quite as long in serious desert conditions. Not yet, anyway. A new model is already in the works to carry both food and medical supplies). This is not an entirely new concept – locals have been doing this in various countries for ages, but in low-tech, less-efficient and less-effective ways.
The outer shell of the device can be made with whatever materials may be handy (including wood or plastic), while the inner drum is crafted from metal. Soaking the layer between both cylinders with water (dirty works just as well as clean, since the inner unit is sealed) begins and evaporative cooling process that keeps the contents cold as long as it remains wet. Beyond making for a neat piece of camping gear, it can help preserve food for people in places without electricity all over the globe.