The Lighting Group, a part of Berkeley Lab's Environmental Energy Technologies Division, is led by scientist Michael Siminovitch, who cooperated with partners in the U.S. lighting industry to bring a prototype design to a manufactured reality within months of conception. 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," Siminovitch says. "The torchieres have caused one of the largest increases in residential lighting energy use in the U.S. They are consuming more energy than compact fluorescent lamps (CFLs) 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 1,000F - 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 100F, 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 also measured the halogen torchieres' light output and three-dimensional distribution in space, using a device developed at the Lighting Lab called a swing-arm goniophotometer. Finally, with standard testing devices they recorded the 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 the group 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 two 36-Watt lamps) to a typical 300-Watt imported halogen torchiere, they found that the CFL lamp produced 50 percent more light and used one-fourth the energy of the halogen torchiere.

According to the Lighting Group's calculations, using a CFL instead of a halogen torchiere will save $136 and use 2,000 kilowatt-hours less electricity over the 7 year life of the lamp, assuming energy costs of 8 per kilowatt-hour. (Halogen torchieres also have a much shorter life than CFLs, usually needing replacement after a year or so.)

This June at Stanford University, Siminovitch and Emess Lighting worked with University authorities to stage a lamp swap on campus. Students turned in their old, hazardous halogen lamps and in exchange received the commercial version of the new CFL torchiere. Secretary of Energy Federico F. Peña applauded the Berkeley Lab for helping to provide students with a safer, more energy-efficient alternative to halogen torchiere's, adding, "I assure you that President Clinton, now a Stanford dad, thanks you as well."

"These new compact fluorescent lamps are not only safer and brighter than halogen lamps, they also will help us save energy and money," said Peña. "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, Page, Jeffrey Mitchell and Linsey Marr have presented their research on halogen torchieres and CFL prototypes at the Association of Energy Engineers Meeting this year. The Lighting Group also welcomes additional collaborations with the lighting industry.

For more information contact Bruce Davies at Berkeley Lab's Technology Transfer Department (510) 486-6461.