Evaporative cooling, a low-tech refrigeration technique, can help keep food fresher for longer, using just water and the sun, and Evaptainers is bringing it back.
Here in most of the developed world, refrigeration isn't a big deal. We have huge electric refrigerators in our homes, and when we head out off the grid, we can easily stop and pick up bags of cheap ice to keep our food cool. Heck, we can even buy a cooler with a built-in blender and waterproof Bluetooth speaker and its own battery bank.
But in many parts of the world, keeping fresh produce and other foods cool is a major challenge, and not just for individual homes, but for the farmers and growers who bring those foods to market. It's not enough to have a refrigerator, because in many cases, the electricity to operate one is both expensive and unreliable due to the state of the local utility grids.
However, there's a time-tested method of refrigeration that doesn't require any electricity or other fuel inputs, called evaporative cooling, which we've covered from time to time here on TreeHugger. These pot-in-pot, or zeer pot, coolers can keep food cool in arid regions (they're most effective in conditions of low relative humidity), but for the most part, they're not made to be portable, so they aren't very useful in keeping food cool during transport from the farm to the market. Unless, of course, the evaporative cooler uses lightweight materials and modern insulation, as the Evaptainers product does, which is why this low-tech solution could have a very big positive effect in the developing world.
Quang Truong, a grad student at MIT and Tufts Fletcher School, was tasked with a class assignment to develop something that could change the lives of a billion people, and after studying about the problem of lack of refrigeration in developing countries, focused on the old-school technology of evaporative cooling. He and Evaptainers co-founder Spencer Taylor have taken on an ambitious mission, which is "To provide affordable refrigeration solutions to address the unique needs and challenges of transporting produce in developing markets." And considering that about 45 percent of produce grown in Africa is spoiled before it reaches the consumer, overcoming the challenge of mobile refrigeration for these small farmers might mean a world of difference for both grower and eater alike.
Evaptainers is applying improved design, modern production methods, and state-of-the-art materials to classic evaporative cooling techniques, and has developed what is said to be "a lightweight, efficient cooling system that can be used in a wide variety of applications." The company currently has some of its prototypes being field-tested in Morocco, and after the end of those trials (summer of 2015), will be looking to commercialize the products for mass production.
The current Evaptainers design can hold about 60 liters of produce, and keep it cool for 12 hours with just 6 liters of water, according to an article in CNN Money. The models are expected to cost somewhere in the range of $10 to $20 each, and are not only simple to operate (and don't have any moving parts to break) but are also said to be tough enough to fall off the back of a moped and still function. By using Evaptainers to store and transport food, farmers could boost their income by about 25%, and the devices could pay for themselves in just a few short months.