Several hundred light poles

On a recent visit to Hartsfield-Jackson International Airport I had occasion to park on the upper level of the South Terminal hourly parking deck. Despite the blazing sun, all of the outdoor parking lights were on (and, I’ll note, they were also on a few days later on another trip). I counted 416 light poles using the aerial photo on Bing Maps, and I am guessing the lamps are 250-watt metal halides (though they could easily be 400 W).

I believe these are 250-watt metal halide lamps

That’s 104 kilowatts of lighting power! If we assume they would stay on all year, and only really need to be on an average of half the time during the year, that’s 8760/2 hours of runtime or 455,520 kilowatt-hours of energy being wasted. For reference, a typical US household uses about 10,000 kWh per year, so this is about 46 homes’ worth of electricity waste.

That probably doesn’t seem like a lot in the grand scheme of operating an entire airport, which must have staggering energy costs, but if the airport pays, say, 6 cents per kWh, this is still about $27,000 per year being used to make the days just a little brighter.