# GE Developing Incandescent Light Bulb That Matches CFL’s Efficiency



## PhotonBoy (Feb 25, 2007)

http://www.environmentalleader.com/2007/02/24/ge-developing-incandescent-light-bulb-that-matches-cfls-efficiency/

"...GE says that advancements to the light bulb invented by GE’s founder Thomas Edison could potentially elevate the energy efficiency of this 125-year-old technology to levels comparable to compact fluorescent lamps...."

_If it can be done, these would be better than CFLs due to the lack of mercury neurotoxins._


----------



## IMSabbel (Feb 25, 2007)

PhotonBoy said:


> http://www.environmentalleader.com/2007/02/24/ge-developing-incandescent-light-bulb-that-matches-cfls-efficiency/
> 
> "...GE says that advancements to the light bulb invented by GE’s founder Thomas Edison could potentially elevate the energy efficiency of this 125-year-old technology to levels comparable to compact fluorescent lamps...."
> 
> _If it can be done, these would be better than CFLs due to the lack of mercury neurotoxins._



Marketing bullshit. 
And totally void of any kind of information about the process (which has to be a hybrid approach, or even the 30 lm/W they promise (which is only half of good CPF) wouldnt be sustainable.))


----------



## InfidelCastro (Feb 25, 2007)

This is good news. I do not like the lighting of compact fluorescent spiral lamps.


----------



## brickbat (Feb 25, 2007)

More info (and opinions) here:

http://groups.google.com/group/sci....30769/3d5196c942cf1675?hl=en#3d5196c942cf1675


----------



## PhotonBoy (Feb 25, 2007)

Brickbat, thanks for the link; I'll read it in depth late tonight.


----------



## 2xTrinity (Feb 25, 2007)

I have often pondered that it would be possible to boost the efficiency of household incandescent bulbs to at least the efficiency of automobile headlight bulbs by doing the following:

1) Use halogen cycle
2) Use a transformer to convert 120V AC to a more optimal voltage -- high voltage lights need to have higher resistance than lower voltage lamps of the same power consumption, which puts tougher restrictions on filament geometry (they either need to be longer and thinner) that tend to reduce efficiency. 12V halogen lights are often double the efficiency of 120V incan of the same wattage. 
3) Use infrared reflective coating to reflect some of the IR back to the filament surface.

Even then though, while I think they may be be able to achieve 30-35 lumens per watt, I doubt they'll be able to top 60 lumens per watt like typical compact fluorescent. Of course, for applications like dimming circuits and lights on motion sensors that get cycled often, they will be a huge improvement as those are areas where CFL doesn't really work.

I got the sense from the article that the product they are coming out with immediately IS gonig to be around 30 lm/W, which probably means it's basically the same as what I described (low voltage halogen with integral power supply) and they expect to top 60 lumens per watt sometime in the future. By then though, there may already be much more robust fluorescents, HIDs, or even some LED lamps to compete with.

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.


----------



## jtr1962 (Feb 25, 2007)

*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.


----------



## idleprocess (Feb 25, 2007)

jtr1962 said:


> 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.


That's what I'm thinking. The incandescent light bulb industry is built on short lifespans and frequent replacement. I think this marketing fluff might succeed since the average person seems averse to spending anything more than the minimum on lighting (CFLs cost a good bit more than incans, making them a tougher sale).

As for their efficiency claims, I have my doubts. You can only make a filament so hot before it melts. I don't think that photon extraction can be improved much without somehow compromising the filament. An internal power supply won't help the cost or efficiency.


----------



## 2xTrinity (Feb 25, 2007)

idleprocess said:


> As for their efficiency claims, I have my doubts. You can only make a filament so hot before it melts. I don't think that photon extraction can be improved much without somehow compromising the filament. An internal power supply won't help the cost or efficiency.


I'm fairly sure that the reason why 12V halogens are more efficient than 120V halogens when comparing bulbs of the same wattage and lifespan is that they are higher current/lower resistance, meaning they can design shorter, thicker, somewhat more durable filaments in a smaller envelope. Of course, going to the expense of an integrated power supply just to get all that, IMO, you won't really be able to compete with CFL for initial price anymore, which is already very low (around $2-3 typically)



> 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.


Agreed, the WH Cree LEDs are the nicest LEDs I've ever seen. The only problem I see with LEDs is that they won't hold be viable as a direct retrofit in many applications, as they are sensitive to heat buildup -- that's the same reason why CFL replacements for recessed can lights take a long time to warm up, they have to design the phosphors etc. run at a much higher temperature. Dedicated fixtures would really be much better.

However, I agree that LEDs will be extremely attractive as they can do things like combine multiple emitters to generate variable color temperatures with dimming -- I know one of the things that bothers a lot of people about the dimmable CFLs is that it looks unnatural for the color temperature to actually remain the same or even go up as the lamp is dimmed, whereas an incandescent decreases in color temperature as it is dimmed. LEDs also have a huge advantage of becoming MORE efficient when dimmed, whereas incandescent bulbs dimmed to 20% brightness that so many people like to run are something like 3 lumens per watt. Next generation LEDs might be able to run at 200 lumens per watt instead at extremely dim levels like that. 

The other area that I woudl love to see is some sort of LED track lighting system with modular optics with different beam angles that you swap in and snap directly to the emitters. LEDs really open the doors for a whole lot of interesting new lighting techniqus that don't really work with either incan or fluorescent.


----------

