Lighting Upgrades Aren't a Flip of the Switch
By Lindsay Audin February 2007 - Lighting
The promises of energy savings and better lighting are strong motivators for facility executives to undertake an upgrade. Too often, though, inattention at various stages of the upgrade process keeps benefits from being realized.
Consider one job where a contractor simply replaced lamps and ballasts without verifying if existing lighting levels were appropriate. Because the existing fixtures had previously been delamped by 50 percent, a dismally lit facility remained uncorrected, greatly disappointing occupants who had been complaining about it for years. In another case, a contractor’s bid was based on a quick examination of the space that missed many locked rooms and assumed some three-lamp fixtures used four lamps. Final costs were higher — and wattage savings lower — than projected, resulting in a much longer payback.
Those two upgrade horror stories show how important it is to pay attention to the details of the upgrade process. At the front end of the process, a contractor’s audit method — including forms and procedures — should be examined during bid review. It is not uncommon to require, for example, that one of each fixture type be opened and photographed as part of a bid submission, and that foot-candle levels (with lights on and off) be taken in all rooms. Alternately, an independent lighting audit may be performed and used as a basis to judge the veracity of contractor claims. It should include interviews and surveys of occupants to adjust lighting levels to better match the tasks taking place. Major savings are often lost simply by replicating existing levels (e.g., excessively high levels where computer monitors proliferate, or in corridors).
Paying attention to the end of the upgrade process can help to verify savings. One reason facility executives are dissatisfied with lighting upgrades is that they don’t see savings in their bills. Before starting the job, understand how savings will be measured and verified. Can lighting feeders or circuits be separately metered with a data logger, for example, to verify wattage before and after an upgrade?
Upgrades often fall short when it comes to incandescent, task, decorative, historical, or custom-designed fixtures and lighting in locked rooms. Too often, they’re simply dropped from the job, leaving many watts unsaved.
The audit should list any locked rooms that could not be accessed. Plan ahead to have all rooms available for both the audit and the upgrade, and build in a second “sweep” near the end of the job to ensure attention to any rooms unavailable on the first try. Pursuing such details may increase total wattage savings by 5 to 10 percent, depending on building age and design.
While it may not be cost effective to replace non-fluorescent fixtures, many types of compact fluorescent lamps (CFL) are now available, including some that fit the mini-candelabra bases in chandeliers, closely mimicking the shape of decorative incandescents. As long as all are changed at the same time in a room, differences from old lamps should not create a distraction. Along with 50 to 70 percent wattage reductions, relamping labor is greatly reduced because CFLs generally last 5 to 10 times longer than incandescents.
Reasonably priced CFL task lights are also available. Audits should include task lights, preferably with a photo of each generic type to simplify replacement. Now that CFL electronic ballasts are smaller, many historical and custom-designed incandescent fixtures are also easy to upgrade, especially where found in large quantity.
Know the New Rules
Don’t expect contractors to know or follow all regulations. It’s unlikely that a building inspector will be checking a lighting upgrade, so some rules may not be followed. Careful specification and bid review prevent problems.
For example, the Americans with Disabilities Act (ADA) calls for wall-mounted fixtures below 6 feet above the floor to protrude no more than 4 inches from the wall. Upgrading an existing fixture that violates that regulation may require altering or replacing to meet the ADA requirement.
Consider emergency lighting as well. Post-9/11, some building codes now require greater levels of emergency lighting coverage. When renovating a fixture with a built-in backup battery, for example, it must be able to operate with new lamps and ballasts.
Facility executives should also be aware of changing federal and state energy codes that may limit wattage, require additional switching or controls, or otherwise affect an upgrade.
Scrutinize Savings Claims
New technologies and research findings offer the potential for greater savings, but it pays to have them reviewed by a qualified lighting consultant before building them into a design.
Some lighting researchers believe that using higher Kelvin temperature lamps (e.g., 5,000 degrees Kelvin) sharpens visibility sufficiently to allow measured foot-candle levels to be reduced by more than 10 percent. Before accepting such claims, set up demo rooms and have occupants verify acceptability of light levels and color.
Some proposals try to factor in higher productivity due to improved occupant control of light level or distribution. However, the fact that occupants like an option does not necessarily mean they will work harder or better.
Daylighting or dimming savings may be highly dependent on existing window treatments, occupant behavior, space layout and building exposure. Don’t accept claims without a demonstration and robust documentation, preferably including a computer simulation reviewed by an independent consultant.
Savings claims for lighting controls need to be checked by a consultant knowledgeable about the local utility tariff or power contract in deregulated areas. Time-of-use or flat pricing, for example, may significantly affect the value of saved kilowatt-hours depending on when they occurred.
Low-wattage fluorescent or other specialized lamps should be checked to ensure they will work properly at all typical room temperatures and with the ballasts that will be firing them.
Higher efficiency lighting means less fixture heat and reduced air conditioning loads, but interactions with HVAC systems can be tricky. It’s safer to be skeptical of such claims and consider any HVAC savings as a bonus. An electrically heated building, for example, may see little or no winter savings when its heating system must use more electricity to make up for reduced heat output of efficient lighting.
Unless controlled by a building management system, it is likely that some lights stay on longer than others, while some are off more than realized. In a few cases, contractors have claimed an upgrade will save more electricity than was actually used by existing lighting. Require that the lighting audit use occupancy loggers to verify operating hours and times in typical or large spaces, and have a copy of the logger’s software printout appended to the audit.
Make Sure the Left Hand…
Problems can arise when facility executives fail to examine interactions among technologies, either proposed or existing. Setting up demonstration rooms and living with a prototype of the planned installation for at least several weeks may reveal surprises.
For example, one facility executive was disappointed when his new system — complete with motion sensors controlling T5HO-lamped fixtures — provided dim lighting whenever the sensors turned them on. The facility executive was unaware of the time delay as T5 lamps warm up to full output. Each time the sensor shut them off, they cooled down, forcing that warm up cycle to restart when someone entered the space, making it appear dim for several minutes.
Some models of electronic ballasts interact with existing clock-setting and book-detection systems, such as those used in schools and libraries. In one building, clocks could not be remotely reset, and book-detection systems stopped operating. A few demonstration rooms would have revealed the problems before the mistake was replicated throughout the building.
Occupancy sensors may also affect the life of some types of CFLs — especially older preheat types still using magnetic ballasts. A five-minute vacancy cycle could cut lamp life by two-thirds, while a 20-minute cycle may minimize the problem.
Verify that new or existing ballasts can accept low-wattage lamps without compromising ballast life or light output, especially in spaces having night setback heating controls.
Facility executives should also pay attention to occupant perceptions. Occupants become accustomed to how they think a space should look, even if that means overlighting or underlighting. The day after a lighting upgrade, the space and its occupants may look quite different.
Demonstration rooms smooth this process. The stage may also be well set by circulating a memo asking employees to wait a week or two before filing complaints or requests for changes. That gives eyes time to adjust to the new look.
In some cases, existing lighting problems, such as glare, may be corrected at no additional cost merely by specifying a different lens or diffuser. As part of the lighting audit, office managers and supervisors should be asked to describe existing lighting problems, and be told this is the time to get them fixed, not after the lighting has been changed.
During the installation phase, a process should be developed to quickly address occupant complaints. Try to pre-empt some of them by posting, several days prior to contractor entry, notices in spaces as to when and how long lighting work will take place.
To cover all bases, ask department administrators or office managers to sign off or provide written comments on an upgrade after it is completed. Doing so reduces post-installation complaints that could result in costly callbacks.
While most lighting contractors can be trusted to do the right thing, it pays to spot check their work. Before verifying illumination levels, however, allow lamps to burn for at least two weeks, or about 100 hours of run time. Output of some lamps may take that long to stabilize.
Where new controls have been installed, be sure that contractors train building staff on how to use them, and provide several copies of manuals for future reference.
Don’t Be Dazzled by Doodads
Some contractors try to include in their proposals high-end equipment that increases their profit margin. Control such behavior by limiting bids to preferred minimum scope, with other options provided as add-alternates showing their incremental cost and projected savings.
When it comes to dimming ballasts, a clear understanding of costs and benefits is essential. Many do not realize that dimming ballasts pull more power when they are not dimmed, potentially canceling some of the savings during dimming. Maintenance may also be an issue. When several dimming ballasts in a package distribution center failed, exact replacements were not available, necessitating use of full output ballasts. Areas illuminated by the dimming ballasts then looked too dark to employees, and complaints caused the dimming controls to be bypassed. In the end, more power was used than if standard ballasts had been installed.
The same outcome may occur if many different or specialized (e.g., high or low power) ballasts or lamps are used in a facility. If inventory and records for all types are not well maintained, it is likely over time that standard lamps and ballasts will replace them, creating bright or dark spots and occupant complaints.
Where new controls have been installed, be sure that contractors have trained building staff in their use, and provided several copies of manuals for future reference.
No lamp or ballast lasts forever, and a few may become defective within a few weeks of installation. To be ready, include a 5 percent maintenance inventory as part of the job, with all materials delivered before final payment is made.
With regard to screw-in CFLs, avoid reversion to incandescents by replacing incandescent sockets with permanent CFL sockets and ballasts where feasible. Eliminate stocks of incandescent replacements, and keep a good stock of CFLs so burnouts are quickly and appropriately replaced.
Doing those things means working with the purchasing department to update their specifications. The purchasing staff may not understand the differences between two similar-sounding but different lamps. It may be necessary to sit down with the purchasing people, show them the differences between lamps and explain why the lamp called for is the one they have to buy — even if they have a supplier offering a “deal” on an older but unacceptable lamp.
Documentation of an upgrade may offer an excellent maintenance resource, providing lamp and ballast quantity and type by room number. At many facilities, time responding to a burnout is wasted because a technician has to be dispatched to see what types of lamps and ballasts are involved, instead of simply consulting the upgrade document listing that information. By specifying that document to be delivered as an Excel file, repairs, group relampings and future changes may be easily input, greatly reducing the cost of future audits.
Energy Savings Is Not the Only Goal
Upgrading a facility’s lighting may offer a lot more than merely cutting wattage. Consider these issues before calling a contractor:
— Lindsay Audin
Lindsay Audin is president of EnergyWiz, an energy consulting firm based in Croton, N.Y. He is a contributing editor for Building Operating Management.