March 2005

Lightening The Load

The rising efficiency of new lighting sources make for an attractive alternative to traditional options.

By Brian Kraemer

Facility managers are faced with innumerable choices when it comes to lighting a facility. The scope of lighting technologies and options is too varied to comprehend within the confines of many facility managers' schedules. Therefore, other considerations can help narrow the field a facility manager has to consider before making lighting decisions.

With the cost of energy trending upward, efficiency should play a key role in the decision making process. Advances in daylighting and peripheral technologies make for an attractive alternative to conventional lighting and the associated costs. Another option is to change lamps entirely. Light emitting diodes (LEDs) and solid state lighting continue to take steps in the process of becoming a feasible lighting option for facility managers. By adopting lighting solutions like daylighting and LEDs, facility managers are in a better position to achieve energy savings and contribute to operational efficiencies.

Why Daylighting

Daylighting is the process where natural sunlight is incorporated into the office environment. Higher amounts of daylight bring certain specific advantages to a building, according to Jonathan Baty, vice president of technology and vice president and CTO of Redlands, CA-based Energy Controls and Concepts and Enerpath Inc. By cutting back the amount of energy, facility managers can significantly lower the cost of operating and maintaining a building.

With a good daylighting system, facility managers can turn off or dim the majority of the lights in a building during the day, which will help to lower the total energy cost. "Assume that the lighting system consumes 100 kilowatts of energy an hour," says Baty. "If you incorporate daylighting into the office environment, you can shed that energy demand. We call those 'negawatt' hours. Instead of having to generate 100 kilowatts of energy, a daylighting system will save the cost of those 100 kilowatts."

How To Harvest Light

"One of the most attractive benefits of daylighting is the low cost of harvesting it," says Baty. On a bright day, the sun provides more natural light than an artificial system in any office building. But in order for these advantages to be realized, the light has to be harvested properly.

According to Baty, there is more to this process than just installing windows and skylights. Without the right controls and surrounding technology, the daylight is combined with the office light and everything becomes a wash. "Once you have penetration in a building, the light still has to be put to use."

"If the daylight comes in and a facility manager is still running the electric lighting at 100%, the space becomes overlit and sometimes becomes overheated as well," says Baty. The trick to energy savings lies in finding the right equipment to complement the bulk of the system.

"Electronic ballasts are becoming the standard for commercial construction, because they tune the light to whatever level is needed," Baty continues. By using electronic ballasts, facility managers can rely on sunlight and dim the amount of light that lamps put out during the day.

Instead of running lights at 80% of their capacity when the sun is most prominent, electronic ballasts can automatically tune the lights to 50%. This results in higher efficiency which, in turn, lowers energy costs. Then as the sun begins to set, the ballasts will raise the light throughout the facility accordingly.

Now, instead of demanding 100 kilowatts an hour all day, facilities can load shed by demanding 80 kilowatts of energy for the majority of the day and increasing the demand as the sunlight lessens.

Added Benefits Despite Limitations

There are, however, limitations to daylighting systems. The most prominent is the difficulty in retrofitting buildings to include daylighting.

"Sure it could be done," says Baty. "But it would be extremely difficult." Adding daylighting to an existing structure is not like changing the locks on a door. The entire roof of a building would have to be reengineered to accommodate the light. In many cases that's not feasible, because the cost is too high or a building simply cannot be outfitted properly, which is why daylighting is an ideal fit for new construction. A facility manager with an eye on energy efficiency should consider daylighting as part of the original plan.

A good daylighting system impacts the overall efficiency of a building by having an effect on more than just the cost of running overhead lights. While energy efficiency is the one desired goal of daylighting, the advantages don't end with the monthly bill. "Sure, there are a lot of verifiable hardline savings in terms of energy," says Baty. "But there are also softline savings: the human benefits."

One softline benefit daylighting can lead to is a reduction in absenteeism. "Basically, people will want to go to work when they work in a comfortable environment," says Baty. Daylighting makes the environment more comfortable to work in and adds to the efficiency of the workplace by encouraging employees to come to the office on a daily basis.

Little White Lights

Since the invention of the light bulb, there has been little change to the design. Incandescent and fluorescent bulbs continue to be manufactured cheaply and as a result, they still control the majority of the lighting market. In recent years, there has been a growing movement toward LEDs with the goal of replacing fluorescent and incandescent lighting. But cost issues and questions about the technology have limited their introduction into the market.

However, LEDs have found use in non-traditional installations because of their robust nature. "LED technology is new enough that it generally isn't cost competitive except in some niche applications," says Grant Harlow, director of strategy and business development for the Vancouver, BC-based TIR Systems Ltd. The flexibility with which LEDs can be installed makes them an attractive option in many difficult to maintain applications.

In order for any lamp to be widely accepted in the marketplace, it has to create bright white light. "White light is light that you can see with-light for doing tasks," says Harlow.

Only recently has technology enabled LEDs to create white light using one of two processes. "The chemistry for creating red, green, and blue LEDs is fairly well known. Recently, a way has been found to combine those colors to produce a white LED. The other option is to use a blue LED coated with a phosphor that glows white," explains Harlow.

Now that LEDs can be manufactured to create white light, the technology is taking off. "They're getting brighter and more efficient very quickly," Harlow says. "In some cases, they are making breakthrough steps."

However, facility managers are not lining up to retrofit their buildings with LEDs just yet. This is because the initial cost of installing a solid state LED lighting system can cause an unaware facility manager an inordinate degree of sticker shock.

However, Harlow continues to be optimistic. "Right now we're looking at targeted applications-boardrooms, atriums, and places where incandescents have been installed."

But breakthroughs in the technology continue. Meanwhile, the energy efficiency of LEDs makes them an attractive replacement for fluorescent bulbs in the future.

Saving Billions

One reason solid state lighting is a particularly efficient source is because of its lumen to watt ratio. "It's the lighting equivalent of miles to the gallon," explains Harlow. LEDs put out a high number of lumens while using a low number of watts. This means facility managers have to buy less energy to light their buildings, which equates to energy savings. "The driving force behind solid state lighting and LEDs is the energy savings," says Harlow.

"The potential energy savings could reach $100 billion a year," Harlow adds. But the technology is not yet ready to replace fluorescent lighting. "It's like having an efficient engine and square tires," continues Harlow. "You need to look at how the light is being generated. In order to make it cost effective, there is still a lot of technology that needs to be developed."

Those in the LED market remain optimistic that new construction will begin to take advantage of the efficiency that it offers. "As the technology gets better-and it will-it will make sense economically to outfit new buildings with solid state lighting and eventually retrofit old ones," Harlow explains. "The energy saving opportunities that will be available are too seductive to pass up."

A facility manager can cut back on energy costs in numerous ways. If the building isn't ready to take the risk and adopt LEDs, the sun still serves as an old standby.

And when the sun is properly harvested and surrounded by energy efficient technology being used the right way, costs can be lowered without sacrificing comfort or productivity. These technologies provide facility managers with more options when considering new construction or a retrofit. If the building is willing to take the initial risk, the energy savings could be tremendous.

Information for this article was compiled from interviews with Baty and Harlow.

Has the lighting in your building affected productivity? E-mail your questions or comments to bkraemer@groupc.com.