Every year in India, millions of gallons of milk gathered by rural  farmers from their small herds spoils on their way to market.
Recently, the co-founder of a U.S. start-up  company that is trying to solve this supply chain problem was named one of  seven ‘invention ambassadors’ in a new program that highlights the value of  technology-driven solutions to global problems. When Sorin Grama graduated with  a master’s degree in engineering and management from the Massachusetts  Institute of Technology in 2007 and started Promethean Power Systems with  entrepreneur Sam White, their goal was to sell solar power concentrators to  generate electricity in clinics and schools in villages without a dependable  source of electricity. But the villages could not find a use for the expensive  technology, so Grama and White turned their attention to the country’s dairy  industry, which is dominated by farmers with a few cows and who depend on  rickshaws, bikes or their own feet to transport the warm milk on the first leg  of its long journey from farm to local village collection centre to the dairy  plant. “Milk really is like liquid cash to them, because milk is something you  harvest and sell daily,” says Grama, an electrical engineer who invented a  refrigeration system to help these villagers keep their milk fresh longer. On July 1, the Lemelson Foundation announced that Grama and  six other inventor-entrepreneurs had been named invention ambassadors. The  event marks the start of a 3-year effort to engage inventors with the public  through talks with everyone from high school students to policymakers. Grama’s  invention is called the rapid milk chiller, a dome-shaped machine that couples  to a thermal energy battery to cool milk from 35°C to 4°C. The rapid milk  chiller cools the milk by means of heat exchange with cold fluid inside the  dome. When electrical power is not available, the rapid milk chiller can cool  up to 500 litres of milk using only the thermal energy stored in the battery.  Dairy plants install the chiller-battery pairs in village collection centres.  Now, villagers can keep their milk fresh for up to 2 days. Dairy trucks do not  have to make daily rounds and no longer have to transport milk from a village  collection centre to a separate chilling centre. The dairy plants can also  extend their reach to more isolated villages with rapid milk chillers.  Promethean Power has sold 60 chiller-battery pairs to dairy processing  facilities in the last 3 years. The company plans to produce more  chillerbattery pairs as demand rises. Grama and White hope to apply their  technology to cool vegetables and other perishable food items.
  (Source: http://news.sciencemag.org/people-events/2014/07)