More than 1,000 flights depart out of Cochin International Airport each week. The travel hub is the seventh busiest airport in India, handling more than 10 million passengers every year. Located in the southwestern coastal state of Kerala, it hosts 27 airlines and some three dozen shops and restaurants — and the whole thing runs on solar energy.

Cochin International became the world’s first solar-powered airport in 2015, when it transformed a patch of land previously reserved for cargo handling into a 12-megawatt solar plant. This new energy source provides all the power the airport needs, and even generates surplus for the state grid,