Applicable Regulations
None.
Overview of Procedure
Occupancy Sensors:
An occupancy sensor is a device that detects the presence of people in a room and
turns off the lights when the room has been unoccupied for a set period of time. When a
sensor detects someone entering the room, it will turn on the lights.
There are several different types of
sensors; some operate by detecting the heat emitted by a person's body, and some by
sensing movement using ultrasonic Doppler technology. It is possible to adjust the time
delay to the specific needs of the area being surveyed.
Dimming Controls:
If it is not practical to turn off all of the lights in a room, it may be worthwhile to
install lighting systems that have dimming capabilities. These allow the reduction of the
lighting intensity in a room during periods of non-occupancy. In addition, dimming
controls can sometimes be used to adjust lighting in response to changes in the amount of
natural daylight.
Waste
Minimization Procedure
Not applicable.
Known
Limitations
Occupancy Sensors:
Ultrasonic sensors are very prone to false triggering from miscellaneous noise.
Infrared depends on the spread pattern of the emitted signal through the occupancy sensor
lens and can have blind spots. Thermal sensors depend upon a change in temperature when a
person enters the room and may not sense any change if the room is already warm (i.e.,
98.6 degrees F).
Dimming Controls:
Not all lamps work with dimming circuits (i.e., compact fluorescent). To get this
capability, it may be necessary to replace both the lighting fixtures and the lamps.
Safety
& Health Precautions/Personal Protective Equipment
Not applicable.
Benefits
The production of
electricity is the largest single source of air pollution from the burning of fossil
fuels. A power plant used to generate electricity burns oil, coal, or natural gas that
emits gases such as carbon dioxide, sulfur dioxide, and nitrogen oxides. These gases, in
turn, cause acid rain, smog, and global warming. Conserving energy reduces the amount of
fuel that has to be consumed, thereby reducing the amount of pollution generated.
Listed below are a few examples of
sensor applications and the typical amount of energy that can be saved in each:
| Application |
Typical
Energy Savings |
| Offices |
15 to
70% |
| Restrooms |
30 to
75% |
| Corridors |
30 to
60% |
| Classrooms |
20 to
75% |
Disadvantages
None known.
Project
Related Costs
Information not available. |
