Santosh Ostwal saw a problem and spent half a lifetime trying to fix it until he finally found the solution in an unlikely place — his cell phone. According to an article in The Economist , as a boy, Ostwal would watch his grandfather walk miles a day, back and forth, to turn on and off the irrigation systems for his crops. The walks were dangerous. Alone at night, farmers faced muggings, wild animals and snakes in what Ostwal saw as an unnecessary journey.

Ostwal knew that life could be easier for Indian farmers and began devising a way to set the water pumps on a timer. In an interview with The Economist , he explains the need that he saw.

There are 3.1 million official connections of water pump sets in Maharashtra alone. The all-India figure is more than 1 billion. While farmers didn’t mind too much with the drill of walking up to the farm to switch on their motor pump sets and then head back home, I found that there was a strong resistance to walk back all the way to the farm to switch off their pump sets. A lot of water and electricity would be wasted.

The road to success was long and difficult. It began with a cheap alarm clock to trigger the system, which, according to The Economist, provided half an answer. It was possible to use the alarm clock to start the water pumps, but it couldn’t then be used to turn them off. While it certainly decreased the amount of walking, it did nothing to improve the water waste or soil erosion damaging crop outputs.

His next solution was to tap into existing radio frequencies using a remote control. This proved to be immensely expensive and difficult to get clearances to work on. Finally, after investing so much money that Ostwal, his wife, and two children were forced out of their apartment, he realized that he could instead tap into the wireless phone network. Within 15 minutes, Ostwal got the result for which he had been searching for nearly two decades.

The cell phone solution, which he has dubbed Nano Ganesh, provides the perfect answer. It uses already existing, cheap technology to start and stop the water flow from anywhere, sparing the farmers their long, dangerous walks. It also prevents soil erosion from excessive watering, which increases crop output for the more than 10,000 farmers across India. In fact, the technology has proven so useful that it is now being used in Egypt and Australia. And it's such a simple fix that it could continue to spread and ease the lives of farmers around the world.

For a full podcast interview with Santosh Ostwal, click here.