May 29, 2009, 9:35 am
Can Incandescent Bulbs Compete on Efficiency?
By Leora Broydo Vestel
Researchers are attempting to create incandescent bulbs that will meet
looming efficiency requirements. The race to find more efficient
lighting technologies appears to have an unlikely dark horse: the
incandescent light bulb.
While traditional incandescents will soon be phased out in the United
States and abroad, researchers are plugging away to create more
efficient versions that comply with looming new standards while also
providing an alternative for consumers who find compact fluorescents
Scientists at the University of Rochester gave Green Inc. an advanced
peek at their newly-developed method for nearly doubling the
efficiency of an incandescent by blackening the tungsten filament with
a short pulse laser. The results of their work will be published in an
upcoming issue of the journal Physical Review Letters.
According to the Chunlei Guo, an associate professor of optics at the
university, the laser process creates a unique array of tiny
structures on the surface of the filament, making it more effective at
radiating light. Regular incandescent bulbs convert only about 10
percent of the energy used into light, while the rest is emitted as
With the same electric power input, the lamp is about twice as
bright, said Mr. Guo. And though the technology is still in the early
stages of development, Mr. Guo believes it would not be difficult for
bulb companies to add a tungsten blackening step to the manufacturing
process. The implementation should be fairly straightforward, he
Meanwhile, researchers at Deposition Sciences in Santa Rosa, Calif.,
have found a way to increase the efficacy of an incandescent to nearly
40 lumens a watt by using reflective coatings that allow waste heat to
be converted to visible light. The light output of traditional
incandescents, depending on the wattage, is between about 10 and 20
lumens a watt.
If you can get up to the levels were talking about, it really
changes the game, said Norm Boling, vice president of research and
development for the company. It means you can have the attributes of
an incandescent and still have the efficiency. You can have your cake
and eat it too.
Lighting companies are already using earlier versions of Deposition
Sciences coatings to manufacture more efficient incandescents, like
Philips Lightings Halogena line, which promises to be up to 38
percent more efficient, with light outputs of up to 23 lumens a watt
and 3,000-hour lifespans.
In Europe, Philips recently introduced the EcoClassic range of
incandescents, which are touted as 50 percent more efficient than
Industry experts believe the price of advanced incandescents
Philips A-shaped Halogenas are about $ apiece at Amazon.com and Home
Depot are expected to come down as more consumers are forced to seek
out bulbs that meet new efficiency standards.
Utilities and government agencies are also considering offering
financial incentives to make them more affordable.
If they save energy and are cost effective, well bundle them into an
incentive program, said Gregg Ander, the chief architect for the
utility Southern California Edison. (California will begin phasing out
inefficient incandescents starting in 2011 one year ahead of the
rest of the nation.)
For all of this, light-emitting diode (LED) and compact-fluorescent
products already on the market have stated efficiency ratings of 40 to
more than 100 lumens per watt, making it difficult to predict how long
incandescents will stay in the game.
Chris Calwell, a senior research fellow with Ecos Consulting, believes
combining various research efforts like those occurring at the
University of Rochester and Deposition Sciences may be the key to
the incandescents staying power.
Based on the pace of the science weve seen thus far, I think we will
be surprised at how good the next generations of incandescents will
be, Mr. Calwell said.
Michael Siminovitch, the director of the California Lighting
Technology Center, described super-efficient incandescents as the
holy grail of lighting research right now.
The stuff is happening, and will happen, Mr. Siminovitch said.
Were all going to be doing it because people hate fluorescents so
The federal Energy Star program does not certify advanced
incandescents. But that may change if the technology catches up to
C.F.L.s, which are purported to use 75 percent less energy than
incandescents and last seven to 10 times as long.
Alex Baker, the lighting program manager for Energy Star, told Green
Inc. that if the performance of a halogen or other advanced
incandescent source rivaled that of currently qualified C.F.L.s, the
program might consider certifying them.
STOP posting other peoples' work / blogs with no comment of your own you lazy
There ARE new incandescent technolgies in the pipeline based on low voltage (
efficient because for complicated reasons they can run hotter ) halogen capsules
integral power supply to run them from the mains in the base, a bit like a CFL
but with a
normal 'hue' to the light instead of what many still find an unpleasant CFL hue
only emits certain wavelengths. On the wavelengths bit, same problem with white
that often look very blue.
due to the hugely increased level of spam please make the obvious adjustment to