Occupancy Sensors For Today’s Offices
Being Green and Saving energy is a big topic for companies. Not only because it saves companies money but also because it’s the right thing to do. And let’s face it, it’s great PR for them – consumers like to know that the companies they buy from, care about the environment.
Hands down the best way to save energy is to not use any at all – call it light abstinence.
And one of the things that can really help is occupancy sensors. They’ve been around for some time, but newer versions have taken the technology one step further, to create a more user friendly product.
Occupancy sensors work the same as a normal wall switch. Except in their case, they can detect when nothing is moving in the room. At that point, they shut off power to the lights.
There are some minor drawbacks.
One of the most annoying things that can happen is when we’re in a bathroom that has an occupancy sensor in it, and the dumb thing shuts off after a few minutes of inactivity, while we’re still there, behind a door. Hello! I’m right here!
Well no more going potty in the dark. (My wife claims I’ve been doing this since we got married.)
New sensors incorporate sound sensitive technolgy that reacts not only to the infared heat of a body when it walks into the room, but also to a person in a bathroom stall yelling, “HEY!! Who shut off the lights?!”
One thing to consider – and this relates to a previous post – when installing occupancy sensors in bathrooms that have fluorescent Lights, make sure you set the sensor to turn off on the longest time available on the unit. When the lights turn off and on a lot, the life of the lamp is greatly reduced AND people get stuck in stalls without lighting – kind of a double whammy.
Jack Huff, along with his son Brian and wife Sue, owns and manages Adventure Lighting in Des Moines, Iowa. For more information, go to www.adventurelighting.com
Excellent article and I definitely agree that setting an occupancy sensor to its longest delay time is ideal for avoiding nuisance offs. Unfortunately, most of the occupancy sensors that utilize microphonics as a technology, do so as a secondary method after passive infrared. Therefore the passive infrared will trigger the occupancy sensor on and then both technologies will hold the sensor on, but if the lights go off, the microphonic technology (“HEY! Who shut off the lights?”) will only turn the lights on within a specific “grace” period. For restroom applications with obstructions, ultrasonic technology on its own or with passive infrared, in my humble opinion is a preferred method.
I will say the occupancy sensor is a very stupid design for me. The reason why I make this conclusion is because:
1. The motion detector need to be on 24hrs a day so it did CONSUMES energy.
2. During the day time, we don’t need the light on but the sensor turn it on for you.
Maybe I am that kind of person who always remember to turn off the light when I left the room while Americans are not. But the government should not impose all the resident to install this in their bathroom. It is extra waste for certain person like me. Every month I need to pay more on my bill.
Thanks for your comments–
I will say that the occupancy sensor, on the whole, is using VERY little energy while it’s “off”, and if everyone turned the lights off every time they walked out of a room then we wouldn’t have this problem. I try to every time, you do every time, and that’s great. On a sidenote, you are able to manually turn them off and they don’t kick on when you walk into the room.
We always say that the point of the occ sensor isn’t to save a few minutes of energy when someone steps out of a room. It’s for the situations where the lights are left on over a weekend or a holiday. Saving the energy over one weekend would equate to the offline energy use of the product in it’s lifetime. Occ sensors aren’t the answer for every application, but in many situations they make sense.
It is a fact that ultrasound is a very poor and expensive technology that does not work in bathrooms with stalls. The sensitivity level of the ultrasound does not pick up movement and return to the sensor. The lights turn off. Tried and tested over and over again and it does not work. Saying it works, does not make it so. The “microphonic” technology easily picks up sound of movement by the sensor due to the hard surface acoustics, and has proven over and over again to NOT leave a person in the dark. Additionally, Ultrasound technology is so poor, many bathroom lights will false trip over and over again causing the lamps to burn out pre-maturely, but still it does not “see movement” in a stall. Ultra-sound also increases the cycles of lamps in classrooms and open office spaces and wastes energy. The sole purpose of occupancy sensors are to reduce energy and increase lamp life. Ultrasound has proven over and over again to increase lamp cycles and have minimal effect on energy savings. Energy audits of ultrasound installations at schools and office buildings have been documented over and over again. Additionally, ultra-sound affects the hearing impaired. WHO, World Health Organization study shows proof.