Remote refrigeration technology saving milk supplies in rural India



Lack of refrigeration in rural India is leading to $10 billion USD worth of fresh produce going to waste every year, including vast quantities of milk, which is a staple of the Indian diet. Lack of a reliable electricity supply is one of the biggest challenges, but an innovative thermal battery, developed by Promethean Power with the help of National Instruments, is now being deployed across India that could eliminate much of this waste and improve the livelihoods of millions of rural dairy farmers.

Promethean Power was able to create a Rapid Milk Chiller (RMC) using a combination of software and reconfigurable hardware from National Instruments, the global provider of measurement and control tools that accelerate innovation among engineers and scientists. National Instruments supported the project through its Planet NI program, which seeks to empower engineers in emerging countries to achieve sustainable prosperity by providing increased access to NI technology.

“If you peel away the layers and look at the underlying cause of that you will find that it is the unreliable electricity in the villages and rural areas where the fresh produce is grown,” Sorin Grama, president of Promethean Power explains. “They are lucky to get 10 hours of electricity a day; 400 million Indians are without access to reliable power.”

Milk management
India is the largest producer and consumer of milk in the world; 102 million gallons of milk are produced annually by rural farmers in India. It is hugely important to the Indian diet and culture. "The milk spoils within five hours if you do nothing with it,” Grama says. “This was the grand challenge that was presented to us by one of our customers in India seven years ago and so we decided to dedicate some of our time working on this.”

Milk comes from millions of individual farmers who have one or two cows and produce five to 10 litres of milk each day. They take that milk to a village collection centre where milk from about 30-50 farmers is accumulated. From there, it will quickly get transported to a chilling centre twice a day, because milking is carried out morning and evening.

“Twice a day armies of trucks will go out, pick up the milk and rush it to a chilling centre,” Grama says. “The problem is that there is a lot of spoilage. India is a hot country and a lot of that milk will spoil along the way. Also the cost of twice-a-day transportation is very high; a lot of diesel is used to get the milk from the villages to the chilling centres.”

An additional problem is that there is not enough supply to meet the demand. The five hour window to chill the milk means that you can’t get milk from too far away. If you can chill the milk right in the village where the farmers are producing it you solve everything in one go. With the unreliable electricity, the only solution was to install a diesel generator, which doubles the capital cost and triples the operating cost, not to mention the noise and pollution.

Power storage is key
“Our task was to find a better solution and after many trials and iterations we have found a better way to approach it,” Grama adds. “The way we have done this is to produce a thermal battery; this is not an electrical battery, it stores energy in the form of thermal energy. Basically we make ice.

“When you make ice you store energy; when you melt the ice you release energy. Along with that we developed a way to rapidly chill the milk and store it, so we developed an entire solution for the dairy industry, something that they could plug in and go. It uses the five or six hours of electricity that they do get in the villages to charge the battery and when the power goes out it just keeps functioning.”

The Rapid Milk Chiller, which is capable of chilling up to 500 litres per collection, gives farmers the ability to chill and store milk even when grid power is out. The milk can be cooled to 4°C in a matter of seconds, arresting bacteria growth and improving milk quality.

At the heart of this innovation are National Instruments products. “We use an NI Single-Board RIO that orchestrates the whole thing,” Grama says. “It monitors all the key temperatures, it controls the system, and it keeps data logging the system which is highly important for food safety validation. We also developed a system to remotely monitor and control the chillers using simple text messaging protocol.”

Aiding development
Rahman Jamal, Technical and Marketing Director of National Instruments, explains: “We are committed to providing scientists and engineers with intuitive tools that enable them to change the world and develop new solutions to the challenges we face in numerous areas, from industry and manufacturing to energy and health. As someone involved in a great deal of humanitarian work, I find it very encouraging to see technology like this being created, which will undoubtedly change lives.”

According to Grama this is the type of project that engineers dream of. “We can eliminate the use of diesel generators in those communities and the social impact is great,” he says. “The farmers get more money for their milk, it creates jobs in villages and ultimately creates a better product for the Indian consumers.”

With the potential to install as many as 1,000 milk chillers in the next five years, each new RMC system has the potential to impact more than 30 farming families thereby having a direct impact on approximately 30,000 dairy farmers and one million milk drinkers in India.

Planet NI Program