Hartsfield-Jackson Atlanta International Airport received the rebate from Georgia Power for upgrades to its runway lighting system.
The airport upgraded thousands of its taxiway fixtures to energy-efficient LEDs throughout its north and south airfields in 2014.
"We're committed to collaborating with our customers to meet their energy needs, improve their efficiency and help them save on their overall energy costs," said Michele Wagner, energy efficiency director for Georgia Power.
"We congratulate Hartsfield-Jackson, and the City of Atlanta, for a continued focus on sustainability and dedication to energy efficiency."
The new LEDs have a longer lifespan than the previous lamps, up to 200,000 hours, and significantly reduce energy requirements.
Areas where LEDs were installed on the runway include runway edge lights, runway centerline lights, runway guard lights, taxiway guard lights and taxiway centreline lighting.
"At the world's busiest and most efficient airport, we work tirelessly to be one of the most sustainable airports in the world," says Miguel Southwell, aviation general manager, Hartsfield-Jackson Atlanta International Airport.
"We are grateful for our partnership with Georgia Power on our airfield LED lighting project and look forward to working together on future energy efficiency initiatives."
Georgia Power estimates that Hartsfield-Jackson may be able to save more than 2,000,000 kilowatt-hours (kWh) annually through the improvements.
The airport is continuing efforts to replace all runway and taxiway lighting with energy efficient LEDs with 6,000 additional fixtures to be retrofitted in 2015.
It has completed more than $6 billion worth of capital improvements, including a new, energy-efficient rental car center, a gold LEED-certified international terminal and aesthetic and functional upgrades to its concourses, people movers and parking services.