By Jillian Ruffino
Published in the April 2008 issue of Today’s Facility Manager
The story of Thomas Edison and his incandescent light bulb is familiar to almost every student of history. But most of them probably don’t know of today’s movement away from Edison’s invention toward more energy efficient lighting technologies. To understand the revolution taking place in the lighting industry, it’s important to look to the past.
Edison’s contribution to facilities is important and ubiquitous; the Edison screw base for a typical light bulb is still in use. But, as Lee Vanatta, president and CEO of PureSpectrum, Inc. of Savannah, GA, explains, “The industry is undergoing a transformation. There are 130 year old patents that dominate a huge proportion of the lighting industry. Now that lighting is coming to the forefront, the industry will need to adapt in a way it has never had to before—with maximum speed.”
Vanatta points out that Edison was testing the incandescent bulb during the American Civil War, and obtained his patents in the latter part of the 19th century. “Would you use any other type of technology that was patented during that time?” asks Vanatta. “Would people use computers that were developed even 30 years ago? How effective would they be at their jobs?”
The End Of An Era
There are two main factors influencing the direction of today’s lighting developments: cost and concerns for the environment. These considerations often go hand in hand, as energy efficient technologies can be more cost-effective in the long-term.
When viewed in terms of the actual energy use of lighting in buildings, it is clear exactly why there is so much activity in this industry’s technological developments. The Energy Information Administration’s 1999 Commercial Building Energy Consumption Survey found that 23% of energy consumption in commercial buildings is dedicated to lighting. Only space heating, at 32%, eclipsed lighting in energy use.
That same study examined energy use by building type. It was found that retail and service facilities consume 20% of all energy followed by office spaces (19%), education facilities (11%), and healthcare (9%). Possible sources in these facilities include incandescent, fluorescent (full size or compact T8s or T5s), metal halide, or light emitting diodes (LEDs).
Of these, Edison’s incandescent bulb is the least efficient; in fact, it may soon become a technology of the past. A new law has been approved by Congress that will set a minimum level of efficiency for all incandescent lighting by 2012.
Denise Fong, IALD, LEED® AP, is a principal at Seattle, WA-based Candela, which specializes in lighting design and consulting. She adds, “Unless manufacturers make the common incandescent more efficient between now and then, it will no longer be manufactured at that point.”
Ceramic metal halide lamps offer some benefits over older styles. They are used for general purpose illumination in high ceiling spaces, wall washing, and retail accent lighting and provide a lower service life when compared with incandescent lights. However, metal halide lamps contain at least some mercury and are not practical for dimming applications. They are also not the best solution for facilities that require frequent switching, since they have a warm up time of five to seven minutes.
Fluorescent lighting has the widest variety of lamps and is thought to provide the best color quality. It is suitable for spaces where diffuse, soft illumination is needed; dimming is a widely available characteristic. Unfortunately, all fluorescent lamps contain mercury.
Kevin Dowling is the vice president of innovation for the solid state lighting group within Philips, headquartered in Somerset, NJ. He says, “Well over 90% of the energy that goes into halogen or fluorescent lighting comes out as heat, so that’s an inefficient way to create light. Fluorescent is, however, the more efficient option of the two.”
Dowling explains that fluorescents provide efficiencies of 50 to 70 lumens per watt (this amount is determined by dividing the amount of light or lumens produced by wattage—the amount of power the light draws). For incandescents, it is between 10 or 15 lumens per watt for large power levels. For fluorescents, it can be anywhere from 50 to 80.
This expert believes there is another lighting technology that could produce more lumens per watt than any technology that came before. This could come in the form of light emitting diodes, or LEDs.
“LEDs are the biggest area of product development and R&D in the lighting industry right now,” says Fong. “They have the potential to be more efficient than any other light source currently available. The technology I’m talking about is not yet available on a broad commercial basis, but it’s getting there.”
For example, as Dowling outlines, LEDs could produce more than 100 lumens per watt some day. He continues: “New LED technologies have been quietly evolving in the background. The industry has now reached a point where LEDs are viable for more commercial applications, and I think we’re on the cusp of shifting toward general illumination applications.”
The history of LEDs follows an interesting trajectory. In the 1970s, nearly 100 years after the invention of the Edison light bulb, the first red LED was created. Various colors followed, including high brightness red, orange, yellow, and green in 1990 and high brightness blue and green in 1995. The use of white LEDs is a fairly recent but important development.
Dowling outlines, “One of the complaints about fluorescents is that people notice the color is either too green or blue. With LEDs, it’s possible to choose the color of a white—either warm or cool.”
LEDs are gaining more attention now for several reasons. Reliability and potential lifetime (up to 50,000 hours) are significant advantages. White light quality and stability are reaching levels found in less efficient light sources.
There are other factors influencing the popularity of LEDs. They are directional, which means they do no waste light (or lumens), and it is possible to create any pattern with them. LEDs offer environmentally sound options, because they do not contain any mercury, lead, or heavy metals.
They also start in nanoseconds. This is true even in extremely cold temperatures. Fong believes this is a major consideration for some users.
“Many people really like that you can flip a switch and the lights turn on; they don’t need to warm up at all. This is what users are accustomed to from incandescents.”
However, the relatively high cost of this technology has been a deterring factor. But, as Dowling explains, “although the initial upfront cost is higher than other light sources, LEDs make sense in terms of total cost of ownership.”
Savings may be seen in the form of maintenance avoidance and energy savings. In the future, improved lumens could also mean lower initial fixture cost along with compliance towards various codes (including Title 24 and the 2012 phase out).
Today, LEDs are used in a variety of environments, including decorative or architectural effects, emergency vehicles, and portable devices. As Fong outlines, they’re being used most broadly in spaces where people are looking for a color changing effect. People are now experimenting more with color in areas where it may not have previously been considered.
In the future, LEDs could be used for task applications, downlights, landscaping, and general commercial effects. LEDs may even make it possible to illuminate spaces in ways that have not been imagined with older technologies.
Dowling predicts: “This will be an opportunity for people to reinvent how lighting is used. For example, users can now make surfaces that are luminous—surfaces that have lights embedded within rather than illuminated from an external source.”
When it is time to make decisions about lighting, facility managers (fms) have a lot to ponder. With all of the talk about energy efficiency, it is easy to get stuck on one consideration without thinking of other factors that should go into purchasing decisions.
“Fms are in a difficult position,” says Vanatta. “They have to make the accounting department happy, so it’s important to pick up on every new energy efficient technology. That’s what affects the bottom line.”
But, as Vanatta continues, fms must also face the people who are working under the lights on a daily basis. They need to be sure a facility’s illumination meets the attributes for a well lit workspace.
“Some manufacturers are coming out with the most energy efficient lighting, but users can’t read by it because the quality is so poor. It’s important to sift through the fine print,” says Vanatta.
Fong agrees: “I think fms need to look at the color quality of the light source, because if that’s not good, it doesn’t really matter how efficient it is or how long it lasts. It needs to provide a good environment.”
Lighting needs to address the specific visual requirements of a space and its occupants, and it must deliver light in a way that works best for the room. The final goal is to do this in a way that is energy and cost efficient.
Current technology developments may help fms achieve success with both goals. Could Edison imagine this evolution of his invention? Probably not!
This article was based on interviews with Dowling, Fong, and Vanatta, as well as from Fong’s presentation, “Energy And Ambience Lighting.”