Technology leads the way in developing more sustainable lighting sources that can produce more lumens, or total light emitted, using smaller sources and reducing the amount of material required to construct lamps. Lighting controls allow designs to increase energy efficiency through the use of sensors that can detect when the space requires light and when there is sufficient illumination through daylight.
Also, world governments are doing their part to ensure a reduction in hazardous waste at the end of lighting fixture lamp life.
Smart Business spoke with Bryan Burkhart, principal lighting designer at Alfa Tech, about sustainable lighting and how it can impact your business.
What are some of the latest developments in lighting?
Technological advances now allow daylight to penetrate far into a building’s interior, both across the space and through ceilings and floors to provide natural lighting to additional levels. Solar tracking systems on rooftops follow the sun throughout the day, which maximizes the sunlight used within a building. Solar concentrators also can boost the natural sunlight levels to generate more available light for the system.
State-of-the-art films that coat the delivery systems channel the light, reduce heat emission and lower the HVAC costs within a building. During overcast days or evening hours, supplemental lighting systems using efficient lighting sources can be activated.
In linear fluorescent lights, reduced mercury T5 lamps come standard with tri-phosphor coatings and produce better color rending qualities, a smaller diameter cross-section and a standard lamp life of 36,000 hours. Reduced mercury T8 lamps have an option for the tri-phosphor coating and a slightly larger cross-section, but offer extended lamp life with 36,000-, 40,000- and 46,000-hour options, which illustrates how far fluorescent lamp life has been extended.
Pulse start metal halide lamps offer a whiter light source than traditional metal halide lamps and a higher color rendering index. They provide up to 15 times the lamp life of incandescent systems and last up to seven times longer than parabolic aluminized reflector and reflector systems. Certain lamping options can provide up to a 50 percent increase in lamp life over traditional metal halide or a total of 30,000 hours when they run for 120 hour periods with a one hour break between cycles. Lighting levels can be reduced when spaces are unoccupied or sufficient daylight is present with skylights. Metal halide fixtures with dual capacitors offer the ability to switch 50 percent of the lights off without extinguishing the lamp entirely.
Light Emitting Diode (LED) sources have the ability for full-color rendering with Red Green Blue lamps. The average lamp life for LED sources is 50,000 hours. The very compact diodes can be dimmed and offer smaller lighting fixtures.
LED technology is evolving rapidly, and light output is continuously pushing more lumens per watts out of smaller packages. Flat panels are one of the most sustainable designs because virtually all of the surface area on one side of the panel emits light. The fixtures are incredibly thin and use only a minimal amount of material to support the panels.
What are some examples of sustainable designs using lighting control systems?
Traditional motion sensors help reduce energy use by turning lights off when no one is around. Daylight harvesting also can control lighting through dedicated sensors that dim lights down when sufficient daylight is present. Sensor control groups of lighting fixtures, defined as zones, turn lights on or off based on motion detected or dim based on daylight sensed. One drawback is all the lights will remain on if a sensor detects the presence of one individual. Additionally, the daylight sensor typically operates separately from the motion sensor so lights could remain on, albeit at a reduced level, even if the space is unoccupied.
New occupancy sensor designs allow the integration of daylight, motion and temperature into a single sensor. The sensor is mounted adjacent to each lighting fixture and provides daylight and motion sensing control. Each fixture looks for daylight or movement in the immediate vicinity. If no movement is detected or sufficient daylight is present, the fixture turns off or dims down. There is also the added benefit of the temperature sensor that can allow variable air volume units to shut off air conditioning or heating when no individuals are present, which maximizes energy conservation.
When a lighting fixture uses a dimmer it can be controlled from 100 percent output down to zero. The importance of dimmable ballasts or LED drivers is that their high and low levels can be ‘tuned.’ In most lighting applications, fixtures can be dimmed to 75 percent of their maximum light output before most people in the space notice. Even when the dimmer is turned on 100 percent it only uses 75 percent of the energy. Some dimming systems require that they never be turned off so that a master controller can override the local dimmer. In these cases, the low end of the dimmer can be set so the light appears to be off, but there is still enough current passing through to allow the master controller to take over when required.
How is hazardous waste from new lighting technology being controlled by governments?
The Restriction of Hazardous Substances (RoHS) directive restricts the use of six hazardous materials on the European Union market for any electrical or electronic equipment that includes lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyl and polybrominated biphenyl ether flame retardants. The intent is to reduce certain hazardous substances from manufactured products. Many U.S. manufacturers are voluntarily making their products RoHS compliant.
The Toxicity Characteristic Leaching Procedure is an EPA standard that determines whether waste is hazardous or nonhazardous. Lamps manufactured to meet this test use 80 percent less mercury than traditional fluorescent lamp designs.
Bryan Burkhart is the principal lighting designer at Alfa Tech. Reach him at (408) 487-1317 or firstname.lastname@example.org.
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