NJ GREEN BUILDING MANUAL
NEW COMMERCIAL UPDATED 9-MAY -11
Sensor Controls
What are Sensor Controls?
Sensor controls include occupancy or motion devices that
turn lights and other equipment on or off in response to
the presence (or absence) of people in a defined space.
Some sensors also control lighting based on the amount
of daylight available in their coverage area. Most sensors
are designed to function independently or with other
sensors for large areas. 1
Figure 1 – Occupancy sensor
(Source: Lighting Controls Association)
Occupancy sensors (including passive infrared,
ultrasonic, and dual technology sensors) serve three basic functions: 2
o To turn on lights automatically when a room becomes occupied
o To keep the lights on while the space is occupied
o To turn the lights off after a preset time when the space has been vacated
Buildings in the United States consume 39% of the country’s energy and 68% of its electricity on
an annual basis. In addition, buildings release 38% of the carbon dioxide (the primary
greenhouse gas associated with climate change), 49% of the sulfur dioxide, and 25% of the
nitrogen oxides found in the air. 3 Sensor controls as part of a holistic approach can help optimize
a building's efficiency and reduce its energy consumption.
How to Incorporate Sensor Controls
There are several common types of lighting sensor controls: 4
1
Whole Building Design Guide, the National Institute of Building Sciences. "Occupancy Sensors."
http://www.wbdg.org/ccb/GREEN/REPORTS/cgrsens.pdf (accessed August 10, 2010).
2
Whole Building Design Guide, the National Institute of Building Sciences." David Nelson, “Electric Lighting
Controls." http://www.wbdg.org/resources/electriclighting.php (accessed August 10, 2010).
3
Whole Building Design guide, the National Institute of Building Sciences. "Optimize Energy Use."
http://www.wbdg.org/design/minimize_consumption.php (accessed August 10, 2010).
4
US DOE. Energy Efficiency & Renewable Energy.
http://www.energysavers.gov/your_home/lighting_daylighting/index.cfm/mytopic=12180 (accessed May 6, 2011).
NJ GREEN BUILDING MANUAL
NEW COMMERCIAL UPDATED 9-MAY -11
o Occupancy sensors work best in indoor environments. Infrared sensors control
lighting by detecting changes in room temperature resulting from body temperature.
They are best applied in smaller spaces since range is limited to about 15 feet.
Ultrasonic sensors detect motion with high-frequency sound. They turn on when they
detect changes in movement, and shut off after a period of inactivity. Dualtechnology sensors combine both methods and are most effective, but are more
expensive. 5 Warehouse aisles are a
typical application for occupancy
sensors because they are often
unoccupied. When used with highintensity discharge (HID) lights,
however, the system is often
modified to turn down lighting
rather than turn off lighting
because of the delay in the lamp’s
full output. 6
o Automatic daylight dimming
Figure 2 - Various types of occupancy sensors and
sensors can be used specifically to
photosensors (Source: Whole Building Design Guide, the
control illumination levels in a
National Institute of Building Sciences - NIBS. David
Nelson, “Electric Lighting Controls.”)
building. The sensor measures the
amount of light in a given space and adjusts the dimming ballast to reach the desired
level of light. Both incandescent and fluorescent lamps have dimming capabilities
when fitted with proper fixtures.
o Motion sensors are activated by motion and are useful for outdoor security lighting.
Incandescent bulbs are turned on and off after a few minutes of no detected
movement. High-intensity discharge (HID) or low-pressure sodium security lights
controlled can take a long time to produce light and therefore do not operate
effectively with motion sensors.
o Photosensors also operate with outdoor lights by switching them off during daylight.
o Lighting timer controls require adjustments for changes in seasons and indoor
activities.
There are also sensors that control lights at fixed points during the day through time scheduling.
Time scheduling can, for example, be set to have lights turned on manually in the morning and
5
Flex Your Power – Residential Product Guides.
http://www.fypower.org/res/tools/products_results.html?id=100200 (accessed May 6, 2011).
6
Focus on Energy - Occupancy Sensors Save Energy & Money by Controlling Your Light. Fact Sheet.
http://www.focusonenergy.com/files/document_management_system/business_programs/occupancysensor_factshee
t.pdf (accessed May 6, 2011).
NJ GREEN BUILDING MANUAL
NEW COMMERCIAL UPDATED 9-MAY -11
turned off in intervals during the night. These sensors can run by a regular clock or by computer
controls, but occupants can still override these controls with a simple wall switch. 7
The placement of sensor controls is critical to optimize their efficiency. The sensor controls must
not detect movement outside their designed coverage area or they will not be effective.
Conversely, they must also extend far enough into all areas of the space to detect motion and
avoid disruptive shut-off. If used properly, these lighting controls can achieve significant energy
savings.
Example
Supermarket Chain uses Occupancy Sensors to Reduce Energy Use
Lighting conversion in the main New England warehouse distribution center in Demoula's
Market Basket supermarket chain includes occupancy sensors in aisles to reduce energy use by
two-thirds.
http://www.energystar.gov/index.cfm?c=business.EPA_BUM_CH6_Lighting
Benefits
According to the Federal Energy Management Program (FEMP), a large office space can achieve
up to 10% energy savings just by installing timers. If timers are used alongside dimming
controls, then electricity savings can reach up to 50%. In spaces where lights are left on often
when the area is unoccupied, occupancy sensors can be utilized to save up to 50% on lighting
costs. Even in smaller office spaces occupancy sensors can produce 30% savings or 10% in
larger office areas. 8
7
US DOE. "Lighting Control Types." https://www.eecbg.energy.gov/femp/procurement/eep_light_controls.html
(accessed August 10, 2010).
8
Flex Your Power - California Energy Efficiency and Conservation. "Controls and Sensors."
http://www.fypower.org/com/tools/products_results.html?id=100119 (accessed August 10, 2010).
NJ GREEN BUILDING MANUAL
NEW COMMERCIAL UPDATED 9-MAY -11
The following table from the U.S. Department of Energy illustrates potential savings that can be
achieved through implementing sensor controls: 9
Performance
Annual Energy
Usea
Annual Energy
Cost
Annual Energy
Cost Savings
Base
Case
5700
kWh
$340
—
Operating Cost Comparison
Open Office Area, 1000 sq. ft.
Time
Occupancy
Daylighting
Scheduling
Sensors
5100 kWh
5000 kWh
4200 kWh
Time Scheduling
+ Daylighting
3700 kWh
$305
$300
$250
$220
$35
$40
$90
$120
a
Average daily "on" hours for wall switch is 9.1. Average daily-occupied hours for the office is 6.8.
Table 1 – Operating Cost Comparison - Lighting
(Source: https://www.eecbg.energy.gov/femp/procurement/eep_light_controls.html)
Costs
The cost per unit for an occupancy sensors ranges from $17 to $240 depending on the type
purchased. Daylight dimming controls require dimmable ballasts in the lighting system which
costs about $35 per unit compared to an electronic ballast which costs about $25.10 Installation
and maintenance costs also need to be taken into account.
There are often incentives for incorporating sensor controls. For example, the New Jersey Office
of Clean Energy offers the following price incentives for various sensor controls:
9
US DOE. Federal Energy Management Program – Technologes.
http://www1.eere.energy.gov/femp/technologies/m/eep_light_controls.html#time (accessed May 6, 2011).
10
Washington State University Cooperative Extension. Daylighting Dimming Controls.
https://pubs.wsu.edu/itemdetail.aspx?productid=15182&seriescode=&categoryid=204&keyword
(accessed August 10, 2010).
NJ GREEN BUILDING MANUAL
NEW COMMERCIAL UPDATED 9-MAY -11
Lighting Control Prescriptive Incentive
Non High Bay Applications Only (bottom of fixture < 14 feet from the floor)
Control Device Type
OSW - Occupancy Sensor Wall Mounted
(Existing facilities only)
OSR - Occupancy Sensor Remote Mounted
(Existing facilities only)
DLD - Fluorescent Daylight Dimming
OHLF - Occupancy Controlled High-Low
with Step Ballast
Incentive per Unit
$20 per control
$35 per ballast
$25 per fixture controlled $50 per fixture
controlled in office applications only
$25 per fixture controlled
High Bay Applications Only (bottom of fixture greater than 14 feet from the floor)
OSRH - Occupancy Sensor Remote
Mounted
OHLH - Occupancy Controlled High-Low
with Step Ballast
DDH - Daylight Dimming
$35 per control
$75 per fixture controlled
$75 per fixture controlled
Table 2 - Lighting Control Incentives
(Source: http://www.njcleanenergy.com/misc/commercial-industrial/lighting-control)
These incentives are subject to change. For current information about NJ’s Clean Energy
Program, see: http://www.njcleanenergy.com/misc/commercial-industrial/lighting-control.
Resources
ENERGY STAR - Lighting
http://www.energystar.gov/index.cfm?c=business.EPA_BUM_CH6_Lighting#S_6_7
Lighting Strategies
http://cbpd.arc.cmu.edu/ebids/pages/group.aspx?group=3
Whole Building Design Guide - Selecting Appropriate Lighting Controls
http://www.wbdg.org/resources/electriclighting.php (refer to the table in section B)
NJ’s Clean Energy Program
http://www.njcleanenergy.com/misc/commercial-industrial/lighting-control
Lighting Controls Association
http://lightingcontrolsassociation.org/