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LED Bulbs Save Substantial Energy

nytimes.com

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Re: LED Bulbs Save Substantial Energy

#31

Post by eru »

ardit33 wrote: post #22
mieses wrote: post #16

Incandescents approximate sunlight better than LED's and most other light sources. http://exploration.vanderbilt.edu/images/news/article_main/q... The health implications should be studied. Subjectively, incandescents are more pleasant than fluorescents and LED's. Our brains might be telling us something.

I agree. For soft lights/ambient lights used with a dimmer, there is nothing yet to substitute the old incandescent. I did some shopping last night, and for my ambient light I decided to go with an incandescent. The extra energy cost is well worth it to me. Sorry environment.

Just be sure to get the right color `temperature' for your energy saving lights. 5000K looks nicer and warmer than the `hotter' 8000K stuff, that you normally get.

Re: LED Bulbs Save Substantial Energy

#32

Post by eru »

Devilboy wrote: post #29
dfox wrote: post #25

Earlier quoted context omitted.

RGB LEDs tend to have very unnatural spectrum with three narrow spikes, while normal white leds (blue led + some phosphor) has very wide spectrum (albeit different from incadescents, but probably better than common fluorescent lights). Other problem that I see with most RGB LED designs is that different colors are emitted from different spots, which tends to give unnatural shadows. Three years ago I built LED lamp ou…

Really what you need to do is match the wavelenghts that our rods and cones in our eyes are most sensitive to. That should be the optimal solution in terms of energy usage.

Perhaps. But it might not be pleasant to the eye.

Re: LED Bulbs Save Substantial Energy

#33

Post by brc »

pmjordan wrote: post #3

Now they just need to come down in price and get the spectrum right. While the fluorescent lights are already competitively priced, LED ones are still rather pricey, at about €15-20. The spectrum emitted by the pseudo-white LEDs is also unpleasant (primarily yellow + blue), the RGB ones need to become cheap enough. RGB lamps could also have some interesting extra features, like adjusting hue based on time of day, whi…

V Australia (a new Australia-USA airline) planes have this feature. The lighting inside the plane varies depending on the time of 'day' they want you to think it is. They often ask to have the window shades closed to enhance the effect. The colours aren't completely natural - they range from a deep blue (daylight) to an orange (sunset/sunrise) to a purple-blue (nightime). It's all done gradually and very subtle.

Subjectively it helped me to adjust to the different timezone during the flight, but it might have just been the 'hey, neato' factor as well.

Re: LED Bulbs Save Substantial Energy

#34

Post by lowkey »

mieses wrote: post #16

Incandescents approximate sunlight better than LED's and most other light sources. http://exploration.vanderbilt.edu/images/news/article_main/q... The health implications should be studied. Subjectively, incandescents are more pleasant than fluorescents and LED's. Our brains might be telling us something.

Funny, I am a co-founder of a HW startup working in the LED space. One of our core patents is based on the concept of 'Polychromatic LED Light.' Our low-cost high-efficiency intelligent LED controls are designed to reproduce the full natural spectrum of lighting - more like natural sunlight than ever before possible.

Incandescents do generate high quality light but they too fall short at reproducing natural sunlight. Unfortunately because Incandescents were dominant for so long the industry has established a color rendering index (CRI) based on a black-body radiator which considers incandescent to be perfect even though it actually falls far short.

Fluorescents and Compact fluorescents produce horrible light as a result of the phosphor coating used to create white light. LEDs can be much better, though admittedly not all are.

All in all LED lighting is the future for a whole host of reasons. I can't wait to replace fluorescents and CFL which, as a result of their mercury content, are one of the most environmentally toxic 'green technologies' ever developed.

Just my, clearly biased, $0.02 :)

Re: LED Bulbs Save Substantial Energy

#35

Post by brc »

I recently fitted all new lighting in my home. I looked at LED lighting, but the salesman was quite honest with me and said that at this point, unless you double the amount of fittings, you're going to be dissapointed. It's not so much the light output but rather the angle of the light - you end up with little star trek beams all over the place.

I bought some CFL spotlights and fitted them into the bathrooms, but I don't like the light quality - it reminds me of an airline toilet. I fitted plain 'ol inefficient halogens to the kitchen, and it's by far the most pleasant lighting in the house. CFL replacements went into all the other fittings.

I haven't noticed any difference in my power bills at all. I suspect that might be to do with the 13 kw air conditioner, pool pump, at least 6 computers running, plasma tv, tivo, exhaust and ventilation fans and exterior lighting. Interior lighting is such a small part of the total energy use in a lot of modern houses.

Re: LED Bulbs Save Substantial Energy

#36

Post by blahedo »

pmjordan wrote: post #3

Now they just need to come down in price and get the spectrum right. While the fluorescent lights are already competitively priced, LED ones are still rather pricey, at about €15-20. The spectrum emitted by the pseudo-white LEDs is also unpleasant (primarily yellow + blue), the RGB ones need to become cheap enough. RGB lamps could also have some interesting extra features, like adjusting hue based on time of day, whi…

They'll probably get there eventually, but considering that CFLs are only just now starting to become legit replacements for some incandescent bulbs---the light quality in a house that went all-CFL during the first big pushes a few years back is appalling---I wouldn't hold my breath.

Re: LED Bulbs Save Substantial Energy

#37

Post by anamax »

Their CFL lifetime numbers don't match my experience. (I typically get longer life from incandescents than CFLs.)

Also, they assume that energy converted to heat is wasted. If you're heating a lit room, that's obviously not true. Yes, many forms of heat are cheaper than resistive, but if you're going to claim to be the last word, you have to account for things like that.

Re: LED Bulbs Save Substantial Energy

#38

Post by jackmoore »

anamax wrote: post #37

Their CFL lifetime numbers don't match my experience. (I typically get longer life from incandescents than CFLs.) Also, they assume that energy converted to heat is wasted. If you're heating a lit room, that's obviously not true. Yes, many forms of heat are cheaper than resistive, but if you're going to claim to be the last word, you have to account for things like that.

Heat generated by a lightbulb is near the ceiling where air is probably not being well circulated. So unless you are installing fans around the base of your bulbs to move the warm air around the room where it would be useful to the inhabitants, it is mostly wasted. This is assuming that the heat is even desirable.

Re: LED Bulbs Save Substantial Energy

#39

Post by stan_rogers »

lowkey wrote: post #34
mieses wrote: post #16

Incandescents approximate sunlight better than LED's and most other light sources. http://exploration.vanderbilt.edu/images/news/article_main/q... The health implications should be studied. Subjectively, incandescents are more pleasant than fluorescents and LED's. Our brains might be telling us something.

Funny, I am a co-founder of a HW startup working in the LED space. One of our core patents is based on the concept of 'Polychromatic LED Light.' Our low-cost high-efficiency intelligent LED controls are designed to reproduce the full natural spectrum of lighting - more like natural sunlight than ever before possible. Incandescents do generate high quality light but they too fall short at reproducing natural sunlight.…

"Fluorescents and Compact fluorescents produce horrible light as a result of the phosphor coating used to create white light." That's a bit of an overgeneralisation -- there's a significant difference between the cheapo tubes and, say, an OTT tube (just one, albeit excellent, example of a full-spectrum fluorescent).

The easiest, cheapest way to get a decent idea of the spectrum is to use a CD or DVD (we've all got at least one coaster at home that used to be a disk). The data side makes a great diffraction spectrometer. A common industrial-grade tube has great gaping holes in the spectrum; an OTT is indistinguishable from indirect skylight (the 6500K "north light" of the studio artist's dream). It's a bit disconcerting at first, probably because we're very much used to incandescent light indoors ("daylight" photographic incandescents might hit 4200K when they're brand new, and they're WAY blue compared to standard bulbs at around 2500-2800K) but it can hardly be described as "horrible".

LEDs aren't quite there yet -- at least none of the ones I've actually seen are. On the other hand, I fondly remember a time when LEDs could not be seen at all outdoors in daylight and drank power at a rate that would have left a plasma TV in an envious rage -- one had to duck into the shade and press eighteen or so buttons simultaneously in order to tell time on a thousand-dollar digital watch. The idea of using an LED (other than a laser) to illuminate anything other than itself was laughable around 1980; the spectrum problem and diffusion are trivial compared to the problems that have already been solved. It won't be long.

Re: LED Bulbs Save Substantial Energy

#40

Post by jerf »

stan_rogers wrote: post #39
lowkey wrote: post #34

Earlier quoted context omitted.

Funny, I am a co-founder of a HW startup working in the LED space. One of our core patents is based on the concept of 'Polychromatic LED Light.' Our low-cost high-efficiency intelligent LED controls are designed to reproduce the full natural spectrum of lighting - more like natural sunlight than ever before possible. Incandescents do generate high quality light but they too fall short at reproducing natural sunlight.…

"Fluorescents and Compact fluorescents produce horrible light as a result of the phosphor coating used to create white light." That's a bit of an overgeneralisation -- there's a significant difference between the cheapo tubes and, say, an OTT tube (just one, albeit excellent, example of a full-spectrum fluorescent). The easiest, cheapest way to get a decent idea of the spectrum is to use a CD or DVD (we've all got at…

Thank you very much for the CD/DVD idea! I see five clear differently-colored copies of my local compact florescent tube in my DVD's rainbow... can you confirm that I am interpreting that correctly as five spikes and virtually nothing in between those spikes?

My local incandescent lights are just a rainbow smear.

Oh, awesome, I can do it to my LCD screen too and clearly see three differently-colored reflections!

...

Forgive my geekout, but that's cool and I've never heard it before.

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