If you're planning a new building or renovation project in the United States in next few years, there's a good chance your building will have plenty of automated lighting features.
Lighting controls such as occupancy sensors, automated stairwell and exterior lighting, parking garage lighting and automated daylight controls are a big part of more stringent building energy codes set to be put in place by many states this October. For most commercial buildings, lighting amounts to one-third of the electricity used.
In October 2011, the U.S. Department of Energy required that states update their building energy codes to meet or exceed ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers) 90.1-2010 codes, which amp up lighting controls over the previous 2007 version. States have a deadline of Oct. 18, 2013 to certify that they have updated the provisions of their commercial building codes regarding energy efficiency.
Similar codes such as 2012 IECC (International Energy Conservation Code) and California's Title 24 2008 Part 6 are considered as stringent as ASHRAE 90.1-2010.
ASHRAE and IECC codes can be very similar. "A lot of provisions in the ASHRAE codes are proposed and incorporated into IECC and can be considered parallel documents that borrow from each other," says David Karmol, vice president for Government Relations for the International Code Council (ICC) that develops the IECC and International Building Codes adopted by many states.
"Buildings that are constructed today by the latest energy codes are about 30 percent more efficient than the average new home or building and add only 1 percent to 2 percent in construction costs," says Eric Lind, vice president of Specification Solutions at
The ASHRAE 90.1-2010 codes contain a lot more lighting control requirements that were not in the 2007 version, including:
- Occupancy sensors with manual-on or auto-on to not more than 50 percent in most spaces.
- Automatic daylight control.
- Light reduction control (bi-level lighting or dimming).
- Stairwell lighting control.
- Functional testing of controls.
The Big Deal in Occupancy Sensing
Under the newer ASHRAE code, the biggest change in lighting control for buildings is far more occupancy sensing. "The addition of occupancy sensor requirements in a number of specific applications is expected to result in significant energy savings," says Doug Hall, senior product manager for control company AMX. "This is a big deal, as it adds occupancy sensor requirements for many specific applications."
Nearly every space in a building will require occupancy sensors, such as conference/meeting rooms, training, classrooms and lecture halls, employee lunch and break rooms, storage and supply rooms between 50 and 1,000 square feet, rooms used for document copying and printing, office spaces up to 250 square feet, restrooms, and dressing and locker rooms.
Many of these "occ" sensors, though, will not be allowed under the codes to turn the lights automatically on, unless it's to only 50 percent. Full auto-on will be allowed in public corridors and stairwells, restrooms, primary building entrance areas and lobbies and areas where manual-on operation may endanger safety or security. This will make many of the sensing devices more "vacancy" sensors than occupancy sensors.
The reason for manual-on? Better energy savings, says Eric Richman, senior research engineer, Energy Systems Analysis at Pacific Northwest National Laboratory and chairman of the ASHRAE/IESNA (Illuminating Engineering Society of North America) 90.1 Lighting Subcommittee. For example, an occupancy sensor could unnecessarily turn on a light in a room that's already illuminated with ambient light, or if someone just peeks his head into a space.
Other Lighting Control Upgrades
In addition, under the ASHRAE 90.1-2010 code all controlled lighting will need at least one control step between 30 percent and 70 percent of full lighting power, in addition to all-off.
Other areas where we'll see more lighting control are stairwells, exteriors, parking garages and daylight controls.
Lighting in enclosed stairwells will require devices to automatically reduce lighting power by at least 50 percent within 30 minutes of vacancy.
Permanently installed outdoor lighting must be controlled by a daylight sensor or astronomical time switch that automatically turns off the lighting during daylight hours. Daylight controls will be required in projects larger than 50,000 sq. ft. And in parking garages lighting must be reduced by at least 30 percent when no activity is detected for 30 minutes.
There are some differences between the ASHRAE 90.1-2010 and IECC 2012 codes. According to Pacific Northwest National Laboratory's Richman, the IECC code does not have as many specific locations where occupancy sensors are required, only requires manual or automatic daylighting control instead of fully automatic, and does not have the detailed exterior lighting and parking garage lighting requirements.
Another difference is in stairwell lighting. "This requirement is not in IECC 2012 or Title 24 2008," says Lutron's Lind. However, the next version of Title 24 (2013 version, effective Jan. 1, 2014) will have the same stairwell requirement."
So what will save the most energy in a building? That depends on the building, its size and its architecture, but occupancy sensors clearly will become ubiquitous. "Occupancy sensors are usually the easiest to install and provide the most cost effectiveness, making them likely to be the most popular choice," says Wayne Stoppelmoor, Schneider Electric's industry standards manager for Energy Efficiency.
"The continued use of occupancy, daylight harvesting and schedule-based control, along with energy-efficient lighting, will have the biggest impact on a building's energy efficiency," says Heath Martin, Product Manager of Schneider Electric's LifeSpace Business.
Buildings will also become much richer in their lighting controls, adds Mike Malone, vice president of Sales at Crestron. "A challenge in code requirements are how to meet them and not break the bank. We need to come up with things that are little more imaginative and creative, like wireless sensors and controls."
When Will We See It?
Most states are still in process of updating their energy codes to be as stringent as ASHRAE 90.1-2010. No states to date have specifically adopted the 90.1-2010 standard. Right now, only Illinois, Maryland and Washington (with state amendments) have adopted the 2012 IECC, and ICC's Karmol says about five or six more states are in the process of adopting it. (And California has the comparable Title 24.)
On the other hand, proposals in several states would delay the adoption cycle to six years, says Lutron's Lind.
Some states may adopt codes statewide and some with limitations and some by local jurisdictions. Some states may not even to adopt the codes, as the DOE requirement for new building energy codes is subject to a patchwork of state and local jurisdictions. "Part of the problem with energy codes is that they deal with real estate, and all regulation of real estate is at the local and state level," Karmol says. "Building codes are traditionally a state and local initiative and authority."
All this is further complicated by a requirement under the American Recovery and Reinvestment Act (ARRA) of 2009 that states receiving funding under the economic stimulus program adopt building codes that meet 2009 IECC standards and achieve 90 percent compliance by 2017.
And yes, enforcement remains an issue. Lind says that some state utility programs and groups such as the U.S DOE-funded Building Codes Assistance Project (BCAP) run compliance assistance programs to help states increase their compliance rates. The DOE also provides technical assistance in updating and enforcing building energy codes though its Building Energy Codes Program.
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