Re: GE Developing Incandescent Light Bulb That Matches CFL's Efficiency
2xTrinity said:
Also, though I seem to be in the minority on this one, I actually prefer higher color temperature lights, and light that is already somewhat diffused, so I doubt incan will ever compete with high-end T8 linear fluorescent fixtures.
Same here-most of the house uses full-spectrum 5000K T8 tubes. I like the color temperature and diffused lighting. I wouldn't say we're in the minority. Rather, it's just that a lot of the population just hasn't used decent high-color temperature lighting. They base their choice of incandescent on the drawbacks of old-school crappy cool-white halophosphor tubes. Also, it takes time for a person to get used to more natural lighting since it makes things look different than they do under incandescent although more similar to how they look under daylight.
Some other thoughts on this:
1) GE is using CFL efficiency as a benchmark but assuming they ever get to 60 lm/W (and that's a big if) by then power LEDs will probably be at least double that, possible even 150 lm/W. Indeed, LEDs will likely make the CFLs these new bulbs seek to compete with obsolete within a few years.
2) Incandescent lighting only remains viable at this point due to the disadvantages of CFLs such as inability to be easily dimmed, poor cold weather performance, shorter life caused by frequent starts, and not coming to full brightness instantly. LEDs suffer none of these shortcomings. Cost is the only thing preventing wide LED adoption in home lighting, and that will come down geometrically as LED production ramps up.
3) LEDs will be able to eventually mimic broadband sources. Indeed, the Cree WH bins come pretty close to sunlight right now except for a slight deficiency in the green region and one in the deep red. I have little doubt LEDs in a few years can imitate sunlight or a broadband source of any other color temperature nearly perfectly, and with much greater efficiency. In short, the niche need for incandescents for those who can't tolerate sources with spectral gaps will easily be filled with LED.
4) GE claims to eventually be able to boost incandescent efficiency but mentions nothing about improving the abysmal 750 hour life to something like the 100,000 hours or more possible with LED. Short life is really the nail in the coffin for incandescent more than inefficiency. Remember that light bulbs have a certain energy cost to make and distribute. Frequent replacement requirements further skew the future towards the LED.
My opinion is that GE sees a huge market in short-lived incandescents about to vanish with the coming of more or less permanent LED lighting and wants to try its best to preserve it. In the end I feel this effort is too little, too late. If they were able to develop a filament material capable of running at 6500K (about the most efficient temperature for an incandescent emitter) combined with IR and UV reflective coating they might have had a shot at breaking 100 lm/W. Perhaps the new filament material could have had super long life, even at 6500K. However, 30 lm/W doesn't cut it. Short lifetime doesn't cut it either. I'm so used to my linear tubes needing replacement perhaps at most twice a decade even when frequently on that I can't fathom how the general public can deal with typical incandescent bulb life requiring replacement every few months. This is especially annoying in outdoor fixtures. It's annoying enough having to replace the CFL on the side light every 12 to 18 months. With incandescents it would be more like every 7 or 8 weeks. And I've burned myself so many times replacing dead bulbs that I never want another light source which gets super hot.
