Revolutionary Fridge Without Electricity Could Transform Millions of Lives

This lightweight, portable cooler is designed to help preserve food for millions of people who either lack consistent access to electricity or have none at all. The EV-8 by Evaptainers uses evaporative cooling to maintain an interior temperature 27 to 36 degrees Fahrenheit (15 to 20 degrees Celsius) lower than the surrounding environment.

The EV-8 is not just for those without refrigerators in their homes. It can also assist displaced refugees in camps and victims of natural disasters where infrastructure has been devastated.

"Typically, it can double or even triple the shelf life of food," says Quang Truong, who developed the concept and co-founded Boston-based Evaptainers with Spencer Taylor.

In Morocco, where Evaptainers has tested several device prototypes, tomatoes last up to a week, compared to just two or three days without the technology. Onions, typically good for only five days, could last anywhere from 10 days to two weeks. The hot, dry climate of Morocco makes it an ideal testing ground for the device, as it performs best in such conditions.

"Some of the world’s most vulnerable populations live in these environments," says Taylor.

These regions — including India, countries in Africa both north and south of the Congolese jungle belt, the entire continent of Australia, and states in the American Southwest — all have an average relative humidity of less than 65 percent. "The drier the air, the faster the evaporation rate," Taylor explains.

After analyzing the data, Taylor and Truong calculated that their solution could potentially aid 652 million people.

Why It's So Cool

Anyone who has ever emerged from a pool on a hot summer day is familiar with the cooling effects of evaporation. The science behind it is simple: heat excites the molecules in a liquid, causing them to rise as gas. As they leave the liquid, they carry away some of the heat, cooling what remains behind.

Evaporative cooling methods have been in use for thousands of years. Ancient Egyptian frescoes from around 2500 B.C.E. show slaves fanning a stone jar to cool its contents. Leonardo da Vinci and Benjamin Franklin both experimented with similar techniques. However, with the advent of electricity and refrigerators, evaporative cooling seemed to fade into the background.

In the late 1990s, Nigerian inventor Mohammed Bah Abba resurrected the ancient clay pot-in-pot cooling system. Known as the zeer pot, it consists of two clay pots, one smaller than the other. The smaller pot fits inside the larger one, with sand filling the gap. By wetting the sand and placing a damp cloth over the top, evaporation occurs, helping preserve perishables inside for longer periods.

It was a remarkable innovation, but it didn’t see widespread use beyond Nigeria.

"The zeer pots last about one or two years before they either break or the pores become clogged," says Truong.

They're also challenging to mass-produce, Taylor points out, and if the user adds either too much or too little water, the pot becomes inefficient.

However, the fundamental idea was sound, and one day Truong had a breakthrough. While taking an entrepreneurship class at the Massachusetts Institute of Technology, he was tasked with creating a product or service that could change the lives of a billion people.

He reflected on his travels through countries like Vietnam, Haiti, India, and Liberia, where the stench of decaying food was often overwhelming. After researching, he discovered that, according to the Food and Agriculture Organization of the United Nations, around 45 percent of fruits and vegetables in Africa spoil before they even reach the market. Truong realized he could evolve the concept of the zeer pot into something more modern, larger, and lighter.

That was in 2012. After refining several prototypes and winning multiple innovation awards along the way, Truong and Taylor believe they're almost ready to bring the EV-8 to market, with plans to sell it for approximately $30 to $35.

Getting to Know the EV-8

The EV-8 features a sturdy top and bottom with collapsible sides crafted from a lightweight material called PhaseTek, developed by Evaptainers. When collapsed, the rigid top and bottom fit together, making the device compact for easy shipping. To expand it, the user flips up fiberglass stays at each corner. Once expanded, it measures 53 cm (21 inches) long, 41 cm (16 inches) wide, and 28 cm (11 inches) tall, with a capacity of 60 liters (16 gallons). For a clearer picture of its size, you can watch the company's explainer video.

To cool the inside, the user fills a designated opening in the lid with 1 liter (1 quart) of water. The water soaks into the four membrane walls, and throughout the day, it evaporates, cooling the interior. The user only needs to refill the reservoir once per day, offering significant water savings compared to the zeer pot, which requires 1 liter of water every 6 to 8 hours.

In May 2017, the EV-8 won its latest honor, the People's Choice Award at FoodBytes San Francisco. This summer, the company is conducting its final pilot test in Morocco before moving forward with full commercialization of the EV-8.

"Everyone on the team is truly passionate about this project," says Truong. "We all firmly believe in the current version of the EV-8, and we know it will be a game-changer for many people."