NEW DELHI — Chilling milk more efficiently is not what most people think of when considering how best to improve global development. However, that is exactly what Sorin Grama set out to accomplish in his efforts to bring technological solutions to India.
According to Grama, “India is the largest producer and consumer of milk in the world”, meaning that milk is hugely important to India’s economy. In order for milk to remain unspoiled, it must avoid excess heat for long periods of time. However, the inconsistent electrical supply in some areas of India means that refrigeration can be unreliable, leading to spoiled milk and lost income.
Typically, a diesel generator is used as a backup power source to account for the unreliability of the electric supply. However, the high cost of diesel fuel means that diesel generators are quite expensive.
Through his company Promethean Power Systems, Grama was able to develop a thermal battery that can replace diesel generators as a more cost-effective backup power source. The thermal battery charges itself from the main power source, requiring only about five hours of energy within a 24-hour period. If the main power goes out, the thermal battery can take over and continue to provide power for refrigeration systems.
With the thermal battery technology, Promethean Power Systems has developed both a Conventional Milk Chiller (CMC) and a Rapid Milk Chiller (RMC). The CMC is able to chill up to 2000 liters of milk per day as a backup power system. The RMC only chills 1000 liters of milk per day, but it can instantly lower milk temperature from 35 degrees Celcius to 4. The rapid cooling is important for inhibiting bacterial growth.
So far, Grama’s company has sold about 300 million milk chillers in India. These milk chillers are literally saving millions of gallons of milk. Not only does this development provide an economic benefit for those in the milk industry, but people are also avoiding exposure to and consumption of spoiled milk, meaning that a health benefit has arisen as well.
The installation of an RMC in the village of Chetawala has resulted in an increase of milk producers from 55 to 75 over the course of 9 months. The village also now collects an average of 700 liters of milk a day, as opposed to 500 before the installation of the RMC.
Thermal battery technology is flexible and versatile, and doesn’t have to be restricted to milk chilling. For example, nearly 40 percent of Indian lettuce goes bad after harvest, according to a case study conducted by Promethean Power Systems. The spoilage results from the same problems plaguing milk collection: unreliable power supply and inefficient diesel generators. The installation of thermal batteries as backup power in cold storage facilities can cut spoilage in half. In just one peak season, the thermal battery-backed cold storage facilities can pay for their own cost with the spoilage they avoid.
The MIT Sloan School of Management has appointed Grama as an entrepreneur in residence to teach a seminar this fall. He is the first resident entrepreneur at the school to exclusively devote attention to the developing world. His work with Promethean Power Systems has already had great success, and his MIT position holds promise in training future entrepreneurs to work on projects of global development.
– Edmond Kim