Tennessee’s Chattanooga Metropolitan Airport has become the first airport in the United States to run entirely on solar power. The small facility, which operates more than 61,000 flights a year, announced it completed work on a 12-acre, 2.64 megawatt (MW) solar farm that generates enough green electricity to account for the airport’s total energy needs, reported the Chattanooga Times Free Press.

The $10 million project, funded largely by the Federal Aviation Administration, took nine years and three phases to complete. It uses onsite batteries to help power operations at night and is expected to last 30 to 40 years. Built in the southwest corner of the airfield, the array is visible from Chattanooga’s two runways on land unusable for aviation purposes. “It’s good for our environment and our bottom line,” Dan Jacobson, chairman of the Chattanooga Metropolitan Airport Authority, said at a press event on Wednesday. He noted that the solar panels make enough electricity to power 160,000 light bulbs.

Officials from nearly 50 airports around the globe have visited or contacted the Chattanooga airfield in recent years to learn about its solar operations, John Naylor, vice president of planning and development for the airport, told Bloomberg News in December. Several major airports, including San Diego and the UK’s Gatwick, have installed solar panels capable of handling a portion of their power needs. And Atlanta’s Hartsfield-Jackson Airport, the world’s busiest, is looking into constructing renewable energy microgrids to power part of its operations. The global leader in clean energy aviation, however, is Cochin International in Kerala, India, which went 100 percent solar powered in 2015, with a 29.5-MW array.