Why are lights left on in skyscrapers at night?

Question

I heard a rumor that it's so that buildings are more visible to planes, and also to give cities a more attractive skyline at night

Answer 1

Ignorance, mostly. When you don't personally pay the utility bill there is little motivation to care if the light gets left on.

Answer 2

display and security.

Answer 3

Two reasons, one, cleaning crew, two, those nice high-stress, high-powered, high-paying jobs in the financial district, are also long-hour jobs.    I used to work in downtown Boston and I've been in the office well past midnight - you do that for 4-5 years and then try to get a job in the suburbs at a smaller firm or bank that will pay you for the knowledge you gained working that kind of job.

The red lights on top of the buildings, those are for the planes.   Generally speaking the planes don't fly over the skyscrapers.

Answer 4

I believe that it is important to have a certain amount of power drawn off the grid all night so that there are no power surges.

Answer 5

not only for planes but also for security purposes.

Answer 6

There are many reasons and you are right with two of them. For planes, attractive skyline. But also for security purposes.

Answer 7

so planes do not hit them

Answer 8

Security mostly.  Sybil there is no need for power draw at night.  There are much more economical methods of regulating available power than wasting it.