A new cart prototype has been designed by Irish company Trane Technologies, for street vendors. It uses passive cooling technology and aims at lessening food wastage.
The Cooling Cart, is part of their social innovation program ‘Operation Possible’. It is a collaboration between the company and students of Cambridge Institute of Technology.
Wilson Lawrence, vice president and general manager at Trane Technologies, explains about the need for such a cart, “Most food loss happens in developing countries. In India, street vendors are the last stop on the supply chain. Almost 30% of fruits, vegetables and greens are getting wasted, due to harsh weather conditions.” The cart solves this problem by placing a canopy over the items displayed.
This canopy has a thin film over it, which will reflect sun rays. This in turn can reduce the temperature of the vegetables by about 6 to 8 degrees Celsius. “This heat reduction is significant because it is done without using any energy. The reduced temperature will help the food to last longer,” says Lawrence.
Another design aspect that helps in temperature reduction — the tilt given to the canopy. “This was added because the sun keeps moving throughout the day. We came up with an optimum angle of incidence,” he adds.
The angle of incidence impacts how much sunlight gets in through a material.
Also, most vendors take left over vegetables to their homes and tie the carts outside.
“With this design, the canopy can move down and acts as a container for the remaining items,” he adds.
Focus areas
Making the cart affordable and lightweight is the team’s top priority. Since this is their first prototype, design changes can occur. “There is a huge lever that is turned to move the canopy up or down. The entire mechanical system behind it is expensive and also cumbersome, as it takes time to move,” says Lawrence.
The team had to let go of some technologically-advanced ideas due to affordability. “In a siphon, to move the water from an upper level to a lower one, one adds a tube, which leads to the water flowing by itself. It doesn’t need any energy. We wanted to use this idea, where a canopy would be on the top, fruits and vegetables at the bottom, and a fluid in the middle would capture solar energy in the morning and use it at night to cool the items below. These ideas can’t be used because they are not affordable,” he adds.
The team also didn’t want to add more weight to the cart as that would make the whole cart difficult to push, “especially in India where there are changing terrains.”
The cart was designed by a team of 15 people, from India, China, Vietnam, Belgium and the USA. The designing process started in early 2021.
Cost factor
When looking at renewable resources, the most abundantly available one is solar energy, points out Lawrence. “We could have placed solar cells on the top but it would have increased the weight of the cart, and would also make maintenance difficult. Compared to such maintenance costs, this prototype will be affordable and efficient,” he explains.