Airport parking lots would normally operate 24/7 and once darkness falls, lights will be a need. Other than safety, proper lighting would help incoming passengers find their vehicles easily but the thing here is the factor of energy consumption that these lamps would consume.

Thanks to Sepco, the Kona Airport in Hawaii is about to enjoy some savings as far as energy consumption from lighting up their parking lot is concerned. About 32 solar-powered streetlights have been installed, using cutoff optics and low sodium fixtures.

The lamps have been sized to run from dusk to dawn, and can power through five days of inclement weather and up to 150 mph winds. The system provides security for travelers returning on late flights, while minimizing the artificial lighting effects on local wildlife, such as sea turtles and birds.

source http://keetsa.com/blog/science-and-technology/solar-power/hawaii-airport-turns-to-solar-powered-parking-lot-lights/