Why are the lights left on in office buildings all night?

Question

If there is a need for security patrols or janitorial or maintenance work, surely motion sensors could be used to control the needed lighting. This is one area that I have never seen addressed by the "Al Gore" fan club or other global warming advocates.

Answer 1

Maintenance occurs in office buildings during late evening to the early morning hours; this would consist of janitorial tasks. In retail outlets, stocking (and related activities) is the primary activity performed during these hours. Please note that there may be exceptions.

These jobs are primarily performed during these hours (as opposed to when the building/store is open to the public) purposely, to prepare the premises for opening the next business day. For example, it would not be practical to rearrange store shelves or to vacuum hallways at other times.

Another reason I have heard is for airplane safety. With the lights on, pilots can easily see the buildings.

I assume that companies have studied the cost effectivenes of installing motion snesors to reduce lighting and if it were cost-effective, they would do it.

EDIT: I thought the airplane reasoning was pretty wacky, but I've seen it claimed as a reason so I reported it.

Answer 2

I agree with you that it's an issue, one among hundreds that are being addressed, although very slowly. The problem is that most people are not willing to sacrifice the feelings of security that street lights and some office building lights offer. No city manager would be willing to advocate for turning off street lights and expect the public to support it. However, many buildings are adding the motion sensor feature but it is mostly a matter of funding. Since it's not considered vital or imperative, more often than not the offices, college campuses, and businesses shy away from spending money they don't have to spend. Personally, the university that I attend is installing motion sensors in all the buildings, but doing it one building at a time because it is expensive to retrofit hundreds of light switches a building! I'm sure that it cuts down on those energy bills though...

Answer 3

It's being addressed by many people. One example.

http://www.seco.cpa.state.tx.us/re_sustain_news.htm

There are standards for energy efficiency for office buildings that specify motion sensors or other means to avoid this. They also specify daylight sensors to turn off lights when there's enough daylight. And dozens of other things. Many more details about how to do office buildings right here:

http://www.sdge.com/forms/OfficeFactSheet.pdf

But there is considerable inertia in business. "We've always done it this way." And the amount of money saved is small in most companies eyes, especially since it requires capital investment in devices. The standards are implemented better in new buildings than old. New building codes help. But it's very hard to require people to retrofit existing buildings, "grandfathering" old construction is a time honored practice.

Answer 4

to maintain an place of work construction thoroughly in the ineffective of evening could be as stupid as having no lighting fixtures furnishings on in a house. I constantly have a mild on in the residing house and on the porch. The darkness is what thieves love the perfect that way no person sees them stealing. Vandals love the darkness so as that they are able to wreck sources. i do no longer prefer to even think of of what different creepy human beings choose a depressing construction to the mild. there is often somebody someplace cleansing the construction, try cleansing in the ineffective of evening, might desire to the risk-free practices human beings wander the construction in the ineffective of evening? the style you do you be attentive to there is no longer human beings working the evening shift?

Answer 5

Maintenance and security have been given, they are obvious.

The less obvious cause is that in buildings which have encorporated energy efficiency into the design the waste heat from lighting is used to heat the building. In that case the small part of the energy that creates light is being wasted, the majority of the electrical energy used in lighting would be wasted as heat energy; that energy is being used effectively, therefore there is a net benefit energy-wise.

That doesn't hold true in every building, of course, but keep it in mind. When you see the lights on, think of it as a small electric furnace keeping the building above freezing.

Answer 6

WONDERFULL Question!!! :) And You're 100% CORRECT; it IS a total waste of Energy- & it's ABOUT TIME it was ADDRESSED- and that buildings had motion senors installed in them (& NONE of this NONSENSE- that it would be "too expensive" to do...-Seeing as how the Electricity SAVED would MORE than pay for the cost of installing them- in NO time!!!). So KEEP asking this Question- & SPREAD the WORD! You could be Intramental in the "greening of America..."! :)

Answer 7

Nor street lights either, a big waste . You wont see Algore talking about big bussiness. For all his big scare on GW he is pretty mild about actually doing something about it except making a profit, he's in bed with big bussiness.
He aint gonna say much cause his mansion burns at least 12 times the amount of one average household in the same given time period.

Answer 8

They usually keep lights on at night so the janitors can work and to scare of burglars and if its an important place its cuz theres security guards there and they kind of need to see so yea lol i hope it helps!!

Answer 9

i think motion detectors are an excellent idea for all vacant or mostly vacant buildings and parking lots.

ok back to the original question - they are left on for cleaning crews most likely.

Answer 10

When employees come to work in the morning, they're too stupid to find the "on" switch for the lights.