BERKELEY, CA — Scientists at the Ernest Orlando Lawrence Berkeley National Laboratory have developed a safer, more energy-efficient compact fluorescent lamp-based alternative to imported halogen torchieres, which have caused at least 100 fires and 10 deaths in the U.S. according to the Consumer Product Safety Commission. These new "CFL torchiere fixtures" are also much more energy-efficient than halogens, saving consumers about $136 over the lifetime of the lamp.
The CFL torchiere fixtures were developed by researchers in the Lighting Group of Berkeley Lab's Environmental Energy Technologies Division. The work was led by staff scientist Michael Siminovitch.
"These new compact fluorescent lamps are not only safer and brighter than halogen lamps, they also will help us save energy and money," said Secretary of Energy Federico F. Pena. "This new lighting technology, developed by Dr. Siminovitch and his team at DOE's Berkeley Lab will help make our environment safer and cleaner. We are now working with the Environmental Protection Agency to move these new lamps from DOE's lab into America's homes."
Siminovitch and his team have been cooperating with partners in the U.S. lighting industry to bring a prototype design to a manufactured reality within months of conception. A Pennsylvania lighting manufacturer, Emess Inc. of Ellwood City, is already selling torchieres based on this design
"Imported halogen torchieres use tungsten-based halogen sources in the 300-Watt range," says Siminovitch. "The torchieres have caused one of the largest increases in residential lighting energy use in the United States, consuming more energy than compact fluorescent lamps are saving. They also operate at high temperatures, posing a severe fire hazard. Halogen lamps are essentially heat sources that happen to generate light."
A recent high-profile example traced to halogen torchieres is the fire that burned jazz musician Lionel Hampton's New York City apartment .
When Siminovitch's group first saw reports of the fire hazard and high energy use of these lamps more than two years ago, they began doing photometric tests in their lab, measuring the light and heat output of halogen torchieres on the market.
Halogen lamps burn at 1,000 degrees F -- so hot that you can't hold your hands over them--and they heat the ceiling and nearby walls, creating the danger that nearby flammable materials such as drapes will catch fire. Compact fluorescents in the Berkeley Lab design produce a wall temperature of only 100 degrees F, cool enough to touch without burning.
The researchers conducted a battery of tests. Using infrared thermography, they took pictures of the heat output of halogen torchieres. They measured the light output of halogen torchieres and their three-dimensional distribution in space using a device developed at the Lighting Lab called a swing-arm goniophotometer. With standard testing devices, they recorded power, power factor and total harmonic distortion.
"Before discussing this work with manufacturers, we built a number of CFL-based prototypes ourselves," says Lighting Group member Erik Page. The design with the highest light output used two 36-Watt F-type CFLs, but they developed designs using a variety of other CFLs and reflector configurations. (Reflectors are sheets of material, often bowl-shaped, that help diffuse the light from the source.)
Comparing their best design (with the two 36-Watt lamps) to a typical 300-Watt imported halogen torchiere, they found that CFL-based lamp produced 50 percent more light using one-fourth the energy of the halogen torchiere.
In technical terms, the halogen torchiere consumes 300 Watts and produces a luminous flux of 3,000 lumens, for an efficacy of 10 lumens per Watt. The Berkeley Lab CFL alternative used 67 Watts and had a luminous flux of 4200 for an efficacy of 63 lumens per Watt.
According to the Lighting Group's calculations, using a CFL torchiere saves money and energy compared to a halogen torchiere. Over the life of the lamp (assumed to be about 7 years), it will save $136 and use 2,000 kilowatt-hours less electricity, assuming energy costs 8cents per kilowatt-hour. Cost savings are higher where energy is more expensive. Halogen torchieres have a much shorter life, with the lamp usually needing replacement after a year or so.
Siminovitch began discussing the problems posed by halogen torchieres at research conferences, attracting interest among manufacturers in developing better alternatives. "Working with innovative manufacturers accelerates the advance of new lighting technologies into the marketplace," says Siminovitch. "Research is only the first step."
Emess Inc. was one of the first manufacturers to approach Berkeley Lab's Lighting Group about developing a CFL-based torchiere product. Within months, the company developed a production model of a CFL torchiere based on the Lighting Group's research. The Group has also advised other manufacturers, and welcomes additional collaborations with the lighting industry.
Siminovitch, Page, Jeffrey Mitchell and Linsey Marr have presented their research on halogen torchieres and CFL prototypes at the Association of Energy Engineers Meeting Denver (April 1997), and are also scheduled to make presentations at the upcoming Illuminating Engineering Society Conference in Seattle and the Right Light Meeting in Copenhagen.
Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified research and is managed by the University of California.