Delamping is another effective method to consider during an upgrade process in existing facilities. It consists of removing unnecessary lamps or fixtures in areas with greater-than-needed illumination
"It's a classic strategy to decrease energy consumption and still retain proper light levels," Casanova explains. "The increased efficiency and light output in some fluorescent lamps helps make this an extremely cost-effective strategy, as you often can take advantage of the existing system, assuming the optics allow for it."
"Moving to a lower wattage is a great idea when the light levels are higher than needed and the ballast accommodates multiple wattages such as what is found in many linear and compact fluorescent technologies," says Smith of Eaton's Cooper Lighting business.
Although removing lamps from existing fixtures can be a good solution when light levels are higher than needed, facility managers should be aware this does not always assure the lighting distribution is maintained, says Smith.
What's more, he says, removing lamps means that parabolic luminaires will normally have cells that are no longer illuminated. The result could be that another lamp will not operate, depending on the way the ballast is wired. So, before delamping, the ballast wiring needs to be examined, Smith says.
"If the ballast is wired in series, it is a must that you should remove all the lamps for that ballast." If not, lamps sharing the same ballast may flicker or produce less light and the life span of those lamps may be shortened. Those cautions usually don't apply to parallel-wired ballasts. "Generally, if the ballast is in parallel, lamps can be removed without removing all the lamps," says Smith.
Before deciding on a delamping strategy, it's always a good idea to explore options with lighting experts.
"The facility manager should perform a lighting assessment to determine which approach is best for the application — reducing the wattage or reducing the number of luminaires," says Teresa Bair, marketing director, luminaires for EYE Lighting International.
NEMA has published a new edition of its popular Lighting Upgrade Checklist for building owners and operators. The handy guide will help lay persons ask the right questions while working with lighting professionals on both new and renovation projects. The 4-page brochure covers Commercial, Institutional and Industrial space, with guidance on lamps, ballast, controls, and luminaires. The Checklist is organized by type of space; offices, hallways, restrooms, manufacturing, warehouse, outdoors, and many others, with specific advice on the latest lighting equipment. Visit www.nemasavesenergy.org and request bulletin number: NEMA.EA.2013.CHKL.V4
The Illuminating Engineering Society (IES) provides recommended light levels for applications that are intended to provide adequate lighting for the tasks at hand in a handbook that can be purchased online in PDF format by non-members for $250 at www.ies.org/handbook/pdf.
Lighting upgrade recommendations can be found at the General Services Administration website under the facilities standards link at www.gsa.gov/portal/content/101308. "While the free data may not reflect the most up-to-date or complete recommendations that factor in age, the nature of the task, etc., they still can offer useful basic guidelines," says Scott Roos, vice president of product design at Juno Lighting Group.
Getting Started On Upgrades To Older Lighting Systems
Fluorescents, Metal Halides, LEDs Are Among Choices To Replace Incandescents
Delamping Has to be Properly Planned to Avoid Problems, Save Energy
Installing Basic Lighting Controls Can Provide Energy Savings