A large clay kiln that looks like the traditional Indian tandoor oven that’s been used in Indian cooking for 5,000 years is providing a simple, practical and sustainable way to let Punjabi farmers get rid of the stubble in their fields without polluting the air. At the same time, it provides biochar which helps them fertilize their fields naturally.

Every year, 27 million tonnes of corn and rice stubble are burned, releasing over 160 million tonnes of greenhouse gases. Much of the field burning is done by small and marginal farmers, who are under pressure to fit as many crop cycles as possible into a year. It’s how the farmers have done it for years, and they didn’t know any other way.

Until the Leo Burnett agency, which has worked with PepsiCo for a year, found a solution that cut pollution while recognizing the pressures on the 27,000 farmers who are part of PepsiCo India’s network of suppliers to multi-crop.