It’s Night: Why’s It So Light?

I woke up in a Tampa hotel room this morning at 3:30 with another of my migraines. It turns out that the cold tap in the bathroom was running about 95 °F, so it was anything but conducive to taking my meds (and was probably leaching lead to boot). This necessitated getting dressed and going down 22 floors to the front desk where at 4 a.m. I was able to get a couple bottles of chilled water. On my way down I was assaulted by bright lights — something neither my sleep addled brain nor the migraine appreciated.

PRETTY BUT WASTEFUL Lights from my hotel room window at 4:15 a.m. J. Raloff
LIGHT ASSAULT Does a hotel hallway at 4 a.m. really need to be this well lit? Cutting illumination by a third to half would still keep navigation safe. J. Raloff

As I was waiting for the meds to kick in, it also got me thinking: Why does the hotel — or the city at large — need to waste so much electricity providing amazingly bright illumination in the middle of the night?

For instance, the light creeping in the window from outside suggested it’s at least dawn; in fact, it’s still anything but outside.

I’m sure all sorts of people would argue that keeping gazillions of lights on fosters safety. But I’d argue that restaurants that won’t open for another 5 hours don’t need to have their balconies and patios lit up. The planters on a bridge to Harbour Island (just below my window) are all brightly lit (which can’t be ideal for the shrubs inside that would like a bit of sleep too).

I’m not suggesting all of the lights need be extinguished. But how about cutting them back by a third? It’s an idea I encountered last week on a trip to visit family in Chicago. As an energy-thrift measure in my aunt and uncle’s apartment building, hallway illumination after 9 p.m. diminishes by about half. The building managers accomplish it my turning off every other light.

Hotels and other places could take a lesson from this. Put those noon-day-bright hall lights on a rheostat at night, or just turn a few lights off, if only between 2 and 6 a.m. Think of it as the nighttime counterpart to daylight savings time: Here it’s nighttime savings time. And it would deliver the added advantage of less light pollution.

Carried out city-wide in towns across America, think how much energy we’d save.

Janet Raloff is the Editor, Digital of Science News Explores, a daily online magazine for middle school students. She started at Science News in 1977 as the environment and policy writer, specializing in toxicology. To her never-ending surprise, her daughter became a toxicologist.