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Parking deck before LED lighting was installed - images courtesy WRAL

Parking deck after LED lights were installed
Raleigh looks to LEDs to cut its power bill and provide brighter lighting

In an effort to cut costs and become more environmentally friendly, the city of Raleigh, NC is looking to LED lighting. The city started a pilot LED lighting program last year in a downtown parking deck. As a result, a 40% reduction in power has been recorded as well as substantial increases in light output, according to Progress Energy.

WRAL, the first HDTV station in the U.S., reports that Raleigh now wants to expand from simply providing LED lighting on a single floor of a parking deck to lighting the entire city with LEDs. The program will eventually expand to use LEDs for street lights, architectural/accent lighting and pedestrian walkways.

LEDs will be provided by Cree, Inc., an RTP-based lighting company. Cree specializes in LED lighting/backlighting used in digital camera flashes, automotive dashboards, traffic signals, street lamps and various other applications.

The upfront costs for providing LED lighting throughout the entire city will be markedly higher than traditional lighting. However, Mayor Charles Meeker notes that the costs could be quickly recovered due to the power savings afforded by LED technology. Meeker says that Raleigh could save roughly $80,000 USD a year in utility bills just by switching its parking decks from traditional lighting to LED lighting. Meeker also believes that significant reductions can be made in the $4 million USD that the city spends to power street lights each year.

"We are thinking by our role of testing these products, implementing those products and then publicizing the successful tests, we can help not just our community, but communities throughout the country to a better job with energy conservation," said Meeker.

"The use of LED lighting will assist in addressing our nation's energy challenges and helping Raleigh and other cities develop energy-efficient infrastructure in the future," said Greg Merritt, a spokesman for Cree.

LEDs are quickly finding a home in a number of varying arenas. Companies like Asus, Fujitsu and Sony have introduced notebooks which use LED backlighting for brighter, sharper screens and reduced power draw. Also, car manufacturers like Toyota and Volkswagen are using LEDs for headlights in their high-end automobiles.



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LED's
By digital batman on 2/14/2007 12:33:48 PM , Rating: 3
I work for the company mentioned in the article (Cree) and one of the biggest hurdles we are experiencing with the adoption of LEDs as standard lights is the cost. Fortunately, LEDs last SO much longer than incandescents or flourescents (I think LEDs are on the measure of 60,000 hours) that the replacement timeframe will allow us to have much cheaper alternatives down the road. As with any technology, the initial cost to early adopters is high but the benefit of longevity ends up outweighing the initial install costs. And the previously stated "costs like 45 cents" is accurate. For the same light as an incandescent, the cost savings is amazing. Plus when one LED goes out on a fixture, all the other ones are still on.




RE: LED's
By fic2 on 2/14/2007 12:46:45 PM , Rating: 2
Could you tell us what the initial cost for one of these garage lights is? I live in a loft building and we are about to replace all of our garage lighting and I would like to have our HOA look at LED. I have already convinced them to go the LED replacement route for the exit signs. Our ROI on that is something like 12 months.


RE: LED's
By digital batman on 2/14/2007 4:09:08 PM , Rating: 2
I don't work in the packaging aspect of the business. I maintain the machines that make them...so I have no idea what a fixture would cost....


RE: LED's
By digital batman on 2/14/2007 5:00:53 PM , Rating: 2
And Cree makes the LEDs, someone else makes the fixtures and basically uses our "parts".


RE: LED's
By patentman on 2/15/2007 6:47:20 PM , Rating: 2
Just an idea of cost. I've seen LED bulbs ranging from $30-$80 a pop, but these are for home use.

http://www.thinkgeek.com/clearance/7aa8/


RE: LED's
By hubajube on 2/28/2007 1:55:30 PM , Rating: 2
I would like to replace the bulbs in my ceiling fans with LED's. Does anyone know where I can get those kinds of bulbs?


RE: LED's
By masher2 (blog) on 2/14/2007 2:12:07 PM , Rating: 3
> "the previously stated "costs like 45 cents" is accurate..."

All the figures I've seen on LED lighting indicate the efficiency is on par with that of fluorescent, and much worse than sodium lamps. A typical fluorescent bulb runs 60-100 lumens/watt, whereas sodium lamps can be double that.

White LEDs available today top out at only ~75 luments/watt (though some lab prototypes are considerably above that. So I'm guessing the 'cost savings' here are due primarily to reduced bulb costs more than any electricity savings.


RE: LED's
By Cogman on 2/14/2007 3:23:55 PM , Rating: 2
A few things about LEDs make them much more promising then Fluorescent bulbs. As I recall, they have a theoretical maximum efficiency of %100. Now that just blows anything that a Fluorescent bulb can do (They are like %30 or so, and incandescent is like %10, if I remember correctly). They also cause less eyes strain then a fluorescent bulb will. I hate to be in a room with fluorescent lighting for too long.

Another bonus to the bulbs is that they don't just burn out (again, I may be wrong here) but instead they gradually decay. That is much better for the consumer (I may be mixing them up with OLEDS).

Anyways, just thought those points should be mentioned.


RE: LED's
By masher2 (blog) on 2/14/2007 3:35:55 PM , Rating: 2
> "A few things about LEDs make them much more promising then Fluorescent bulbs..."

Long-term promise, sure. I certainly agree. I'm simply pointing out that current LED lighting solutions are not more energy-efficiency than a good fluorescent, and much less efficient than the sodium lights most municipalities use for street lighting.

> "They also cause less eyes strain then a fluorescent bulb will..."

There are flickerless fluorescent bulbs, though as they're more expensive, they're not as widely used.

> "Another bonus to the bulbs is that they don't just burn out..."

They can do so, though this is much rarer than for other lighting solutions.


RE: LED's
By digital batman on 2/14/2007 4:14:14 PM , Rating: 2
And as I hinted at before, when an LED in an LED fixture dies (tens years from now), the fixture still works (albeit with one less light). When a flourescent fixture (or halogen or sodium for that matter) dies, the fixture no longer produces any light.


RE: LED's
By masher2 (blog) on 2/14/2007 4:19:21 PM , Rating: 2
Actually, most commercial fluorescent fixtures contain multiple bulbs, so when a single bulb dies, the fixture still produces light.

No one is arguing the greater longevity of led lighting, nor its future promise. However, the current level of technology has indeed been somewhat overstated.


RE: LED's
By ZmaxDP on 2/14/2007 4:18:13 PM , Rating: 3
Just to contradict some things said here. I worked in an architectural materials library and lab for three years(up until about 6 months ago when I got a "real" job.) One of our focuses was architectural lighting technologies. For starters, the LED lamps we had in our lab were about 10 times more efficient than the CFL lamps we had, and those are about 10 times more efficient than the common incandescent lamps. We had almost every conceivable lamp hooked up to individual watt meters and monitored them over the course of a year. These were all "current" technology. So trust me, LEDs are more efficient currently. I don't know where you got your figures from, but someone was fudging the numbers somehow I think.

Also, there is no such thing as a "flickerless" flourescent bulb. There are "flickerless" flourescent fixtures. What makes a flourescent (or any gas reaction bulb - like sodium lighting) flicker is the frequency of the electrical current running through the gas. Old flourescent fixtures had ballasts that changed the frequency to something noticeable, hence the "flickering." It's basically like taking an old CRT monitor and changing it's frequency to 50 Hertz. You'll see it. Old flourescents hit 60 Hertz I believe, but that's going off memory and I'm not vouching for accuracy on that one. Modern flourescents are usually double or triple that figure so that we can't "perceive" the flickering, though it is still occurring. (Just FYI). You can put a fancy new flourescent bulb in an old fixture and it will flicker like it's 1969. Put an old bulb in a new fixture and you'll see no evil - though it will still be there.

Some of the eye strain from flourescents is also in the color of the light (vs. daylight, etc...). The other is from the flicker. If your bulbs don't flicker, then it's color that's the problem. LED's aren't perfect, but color wise they're much closer to sunlight than older flourescent bulbs. (You can also buy "natural" flourescents now that have a film to convert the natural output of flourescent to something nicer - basically a photography filter around the tube.) I would mention that there are two kinds of LED bulbs on the market. There are "monochromatic" bulbs which use white LED's the generate white light (which lack much of the spectrum) and there are tri-color LED's which replicate sunlight much better (even than incandescent bulbs) These are less efficient than the monochromatic ones, but not much. They are also more expensive though, and since both increase, that might be an issue.

Still, if you can afford the initial investment, they will save you money two ways. They are more efficient than any other light source we currently have (even sodium lights - we had one of those plugged in to, and yes we adjusted the figures for light output. We measured lumens at three distances and used this distribution to do performance/watt on each lamp. I only wish we'd checked output more often as I can't say much on how output degraded over time. We didn't own the light meters, only borrowed them a few times over the year.

Hope I cleared a few things up. If you've got conflicting figures that you've measured, or a report somewhere, I'd love to see them because I want to know how they got their results. I at least know how I got mine.

Adios!


RE: LED's
By masher2 (blog) on 2/14/2007 4:33:28 PM , Rating: 4
> "I'd love to see them because I want to know how they got their results. I at least know how I got mine..."

My figures come straight from Cree's website, the provider of these fixtures. They quote a 78 lumen output from a 500mA led, driven @ 3.5V. The math on that works out to 44 lumens/watt, or less than half what you get from the best fluorescent bulbs. I've seen research papers on LEDs that can do 150 lumens/watt...but those are not commercially available. And even those are less efficient than sodium lighting.

> " We had almost every conceivable lamp hooked up to individual watt meters..."

Ah, but to measure luminous efficacy, you need both a wattmeter and a specially-calibrated lightmeter. Did you have both?

> "there is no such thing as a "flickerless" flourescent bulb. There are "flickerless" flourescent fixtures."

True, but the end result is the same. And, since more and more fluorescent bulbs incorporate the ballast and fixture with the bulb, the distinction here is rather sterile.

> "LED's aren't perfect, but color wise they're much closer to sunlight than older flourescent bulbs..."

Untrue. Fluorescent bulbs are sold in a wide range of color temperatures. Furthermore (as I've already explained in another post) common white LEDs don't actually have a color spectrum at all...they produce two (for the cheapest variety) monochromatic light sources, which the eye perceives as white, even though the reality is quite different.


RE: LED's
By digital batman on 2/14/2007 4:54:33 PM , Rating: 2
And drawing from information on Cree's site, there are several "powers" of lighting. For instance, there is a company LED Lighting Fixtures here in RTP that is producing a fixture using our LEDs that produces 650 lumens with a 10-12 watt input. I am not being confrontational here, but is there another similar output from a different type of fixture (asking because I don't know)? And for the most part in all of our posts so far, we have been comparing one light for one light. The number of LEDs that would be used in the place of a similar commercial application of flourescents or sodium lights would produce a much larger total light using less power and occupying the same amount of space. I wish everyone could come to Cree and browse the demo room. You would be impressed with the amount of light LEDs in the same space as a 4' flourescent put out.


RE: LED's
By masher2 (blog) on 2/14/2007 5:24:30 PM , Rating: 2
> "For instance, there is a company LED Lighting Fixtures...using our LEDs that produces 650 lumens with a 10-12 watt input..."

Which works out to ~60 lumens/watt. Again, below that of fluorescent, and far below sodium lighting.

> "I wish everyone could come to Cree and browse the demo room. You would be impressed ..."

Figures don't lie. LED lighting certainly is more compact and long-lasting than other approaches. But its not the most energy-efficient choice...not yet, at least.


RE: LED's
By lemonadesoda on 2/14/2007 8:42:18 PM , Rating: 2
A designed-for-purpose fluorescent lighting circuit would have a voltage frequency doubler at the SOURCE... ie. no need for expensive converters in EACH light fitting. Just a regular wired fitting, now receiving 100hz or 120hz (depending on country). That reduces flicker considerably.

This is becoming more and more common in libraries where most of the lighting is fluorescent. When I was in college I couldnt work in the library... I have eyes very sensitive to flicker. (A quite common problem)


RE: LED's
By FredEx on 2/15/2007 12:52:31 AM , Rating: 2
I've recently read where the measuring of lumens output when it comes to LEDs can be extremely misleading. The reason is that lumens measurements are made at several points around a bulb and averaged and an LEDs most powerful output is out forward at a somewhat narrow angle. That is why an LED fixture may have the outer LEDs angled outward to spread the light or they use some sort of diffuser to spread the light. Take any other lighting source mentioned and measure its output at only one point, similar to the point of an LEDs maximum brightness, and you will get a measurement far less than the LED source.



RE: LED's
By mindless1 on 2/14/2007 3:40:46 PM , Rating: 2
You don't remember correctly, LEDs actually being used are less efficient than fluorescents actually being used. If we want to talk theory, in theory if we go without lights for long enough our eyes will become accustomed to the dark via evolution. Let's ignore theory and focus on what's available to use now, or even more specifically, what's not just available but at reasonable price-points, there are really expensive LED lights and then there are obscenely expensive LED lights.


RE: LED's
By masher2 (blog) on 2/14/2007 3:58:52 PM , Rating: 3
> "You don't remember correctly, LEDs actually being used are less efficient than fluorescents actually being used."

Actually, my first statement was quite correct. First of all, I said "on par"-- not "equivalent". Point of fact, LED lighting is more efficient than some fluorescent tubes. Both types of lighting have a wide range of efficiency values...the best fluorescents beats LEDs, but the worst one are well below the best LEDs.



RE: LED's
By ZmaxDP on 2/14/2007 4:25:16 PM , Rating: 2
Just to clarify further - we selected lamps that had the best efficiency ratings in their class. - As they were listed. We did not test these initial values indipendently. So, we may not actually have had the most efficient lamps on the market for each sector. We just think we did.

Also, we then used our measured lighting values (not the listed values) to determine actual efficiency for each bulb. As another poster states, some lights are more directional (and therefore "efficient") than others. Our tests were based on directional output, and so it could be true than flourescents compare more favorably in situations where directional output is not important, indirect lighting for instance. We didn't test this scenario, so I won't make any claims on it.

Oh, and these tests were done starting about a year ago (maybe 14 months), so "theoretically" the technology for LED lamps should have improved..


RE: LED's
By masher2 (blog) on 2/15/2007 8:20:18 AM , Rating: 2
I'd be curious to see your published reports then, as your results differ from every other research institute in the world. LEDs certainly beat incandescents in luminous efficacy...but then, what doesn't? They still come in behind fluorescent and far behind sodium lighting.



RE: LED's
By jnypts on 2/15/2007 4:03:07 AM , Rating: 2
Hmmm, I don't quite see how evolution would take care of that one. To evolve better eyesight you would have to be a more desirable mate if you could see better in the dark, or your children were more likely to survive long enough to reproduce themselves. And it seems to me that you are far more likely to be bypassed by potential mates for sitting in the dark trying to evolve than to turn on the light.


RE: LED's
By digital batman on 2/14/2007 4:41:12 PM , Rating: 3
That is OLEDs. When a normal LED dies....it dies..


RE: LED's
By digital batman on 2/14/2007 4:12:35 PM , Rating: 2
One problem with specs is that lumens is very subjective. LEDs, being a very directional light, with a lumen rating of 75/W would pretty much be in the 70-75 lumens/watt usable range. A flourescent, since its light is radial, is measured at 70 lumens/W (no idea if that is an accurate number or not, just for sake of argument), means that actual "usable light" might be more on the order of 30-40 lumens/W. A lot of the light coming from a flourescent is lost as it heads towards the fixture and to the sides.


RE: LED's
By masher2 (blog) on 2/14/2007 4:37:41 PM , Rating: 2
> "A lot of the light coming from a flourescent is lost as it heads towards the fixture and to the sides..."

Very little, if the fixture has a decent quality reflector. The albedo on silverized metal can easily be 97% or higher.


RE: LED's
By digital batman on 2/14/2007 4:47:10 PM , Rating: 2
I was more referring to the fact that LEDs are pretty much producing light directly in front of them WITHOUT any reflection or loss of light laterally. Flourescents, even with good reflectors are still sending light that is part of their total energy to the sides and back, resulting in a loss of heat and energy that is not reflected, affecting their perceived light.


RE: LED's
By saratoga on 2/14/2007 5:03:29 PM , Rating: 2
quote:
Very little, if the fixture has a decent quality reflector. The albedo on silverized metal can easily be 97% or higher.


97% is probably measured at a 90 degree angle. For non-normal reflection, the coefficient is generally much less for common materials, perhaps by a factor of two or more. Since we're talking a radially symmetric source, you'd need to use an average reflectivity, not a peak, in which case absorption may be significant at best and crippling at worst.


RE: LED's
By masher2 (blog) on 2/14/2007 5:33:09 PM , Rating: 2
> "97% is probably measured at a 90 degree angle...Since we're talking a radially symmetric source...."

A parabolic or even a half-circle reflector around a radially symmetric point source has near a normal (90 degree) reflective angle at all points. Reflectors designed for research applications can hit 99.95% efficiency. I don't know figures for commercial fixtures, but its certainly not going to be more than a few percent loss, nowhere near enough to make up a large difference in luminous efficacy.



RE: LED's
By chaos386 on 2/15/2007 5:48:32 AM , Rating: 2
Lumens are measured as light output per steradian, so if the fluorescent light has the same lumen rating as an LED it will actually be outputting more total light, not less.


vs. CFL
By ninjit on 2/14/2007 12:34:47 PM , Rating: 2
How do LEDs compare to CFL bulbs?
Initial cost and efficiency-wise?

One of the main problems that slowed the adoption of CFLs was that the light they produced wasn't very "warm" compared to regular incandescent bulbs - ok for offices and such but a bit bleh for a home - thats largely been solved now with the availability of CFLs with more pleasant spectrums.

Seems to me LED lighting would suffer from the same problem - it's incredibly white.




RE: vs. CFL
By thebrown13 on 2/14/07, Rating: 0
RE: vs. CFL
By Scorpion on 2/14/2007 1:01:56 PM , Rating: 2
You mean how to compensate for your aquired comfort with incandescent lighting? Sure, it's a bit different at first, because the light is "whiter". LEDs also don't give out that lite flourescing effect that flourescent bulbs do, however, which is very uncomfortable over long periods. Research can and has been done to determine which light spectrum provides the most "natural" comfort to our eyes, and can be adopted into future LEDs. This is another advantage of LEDs, the fact that they can produce clean visible spectrum without the disadvantage of introducing the effects of other non-visible spectral components.


RE: vs. CFL
By rockyct on 2/14/2007 1:13:03 PM , Rating: 2
They are starting to mass produce "soft white" LEDs.


RE: vs. CFL
By masher2 (blog) on 2/14/2007 2:04:37 PM , Rating: 2
> "You mean how to compensate for your aquired comfort with incandescent lighting? Sure, it's a bit different at first..."

Its not a matter of "acquired comfort". The color spectrum of white LEDs is substantially different than that of an incandescent bulb. The latter is more closely matched to that of the sun...the lighting source for which billions of years of evolution has prepared us.

Certainly, LEDs can be developed with a wider, more natural spectrum. In fact, they already exist. However, they're substantiall ymore expensive than the standard blue+phosphor approach used by current white LEDs.


RE: vs. CFL
By darknodin on 2/14/2007 2:58:12 PM , Rating: 2
actually, incandescent is quite a bit yellower than the sun (i think its the temperature difference). i noticed this when installed LEDs in the sunlight. they actually looked like sunlight reflections. I think they are still a bit bluer though


RE: vs. CFL
By masher2 (blog) on 2/14/2007 3:11:13 PM , Rating: 3
> "actually, incandescent is quite a bit yellower than the sun... "

They have a cooler spectrum than sunlight, yes. However, its not "quite a bit" so, not when compared to lighting solutions like fluorescent and LEDs. The largest problem with current white LEDs, though, is the narrowness of the spectrum. The most common ones don't really have a "spectrum" per se...they're just two monochromatic sources (a blue LED coupled with a yellow phosphor). The light they emit has the appearance of white to our eyes, but its a far cry from the real thing.

There are some prototype LEDs using quantum dots have a much wider (and warmer) spectrum, but they're not commercially available yet.



RE: vs. CFL
By Oregonian2 on 2/14/2007 3:35:10 PM , Rating: 2
I agree with everything you say!

For those who think incandescents aren't a LOT yellower than LEDs or sunlight, any photographer (of the film variety that doesn't do digital auto-balancing of color spectrum) will tell you that it is. Use daylight film (that doesn't "lie" as such) and normal house incandescents show to be VERY yellow.

It doesn't LOOK as yellow as they are because one's brain does something similar to that which digital cameras do. One's brain will "adapt" partially to the change of light spectrum and make colors look more natural. If one has a incandescently lit room with a window that tightly seals light and have the window open during a sunny day (so that the window light dominates) and then quickly close the window, one will see (for a short while) how tremendously yellow the incandescents are (and how one's brain adapts).

Alternatively look at the dark blue filter one uses to adapt daylight film for tungsten (incandecent) use. Film doesn't have the brain or software to auto-adapt the light source and tells it like it is (at least well enough for something this gross).

So the difference between LEDs and Sunlight is relatively small. That said, "Sunlight" has a VERY wide range of color temperatures from sunrise to sunset (on clear days). Obviously can be very orange at the end-points and is VERY VERY blue at mid-day (way over 10K degrees color temp). Probably depends where one lives as well and the season. :-)




RE: vs. CFL
By saratoga on 2/14/2007 4:50:13 PM , Rating: 2
I have to agree. Anyone who has done photography without color correction on the camera or film would not claim incandescent is anything like sun light. Its not even close. Without exposure compensation, sun light tends to look very good while incandescent is almost unusable.

While the sun maybe yellow-biased approaching the Earth, the atmosphere preferentially scatters blue and lower wavelength light down to the surface which helps compensate for the coloring.


RE: vs. CFL
By masher2 (blog) on 2/14/2007 5:40:36 PM , Rating: 3
No one is claiming incandescent matches the solar spectrum. However, the fact remains its a far closer match than is the psuedowhite produced by a single-phosphor white LED.


RE: vs. CFL
By Oregonian2 on 2/15/2007 7:52:12 PM , Rating: 2
Nope, that was my point. Incandescents are yellow as heck while while LEDs that I've seen look pretty good, rendering things I see lit by them having good color. At least one white-LED light I have that I've looked at during the day (windows open) still looked "white", while an incandescent under the same conditions look yellow as heck.

So perhaps it depends upon what you mean by a match and how well that measurement method matches up with the usage that the comparison is being made for. Not being continuous tone blackbody radiation may not matter.

Incandecents aren't even "psuedo-white", they're "really yellow".



RE: vs. CFL
By bfonnes on 2/15/2007 8:46:32 PM , Rating: 2
Has anyone read Carl Sagan? He says the sun is actually closer to pink than yellow at least from the true perspective of space. It only "appears" to us to be yellow.


RE: vs. CFL
By Oregonian2 on 2/16/2007 1:04:37 PM , Rating: 3
To tell the truth, I don't know why it's thought to be yellow (other than it being drawn that way in cartoons and story books seen when I was a kid). Although I don't look at it directly (I can still see) at mid-day it's more blue. Looks only yellow-ish at sunrise/sunset for reasons we already know. Most of the day it's not yellow.

P.S. - But then, I'm "trained" that dogs say 'woof'. Heard a LOT of dogs, not one has said "woof" as of yet. I'm not so confident in the accuracy of my childhood training. :-)


it's about time
By estaffer on 2/14/2007 12:35:44 PM , Rating: 2
LEDs have been around for some time and if the benefit is really that good, why not switch?

it's all about efficiency these days.




RE: it's about time
By fic2 on 2/14/2007 12:49:44 PM , Rating: 2
Usually it is the upfront cost. Plus I don't think that white LEDs were produced until about 5 years or so ago. Also, the lumens for white LEDs are still being ramped up. Denver has changed all it's red/green lights to LED. They are brighter, use less energy and last for something like 10 years.


RE: it's about time
By boffo on 2/14/2007 1:17:02 PM , Rating: 2
And the upfront cost can be the real killer, especially with commercial real estate like downtown high rises. The reason the owners of such buildings -- where the electrical bills are so massive -- are unlikely to switch soon is the same reason why they are reluctant to retrofit the buildings with any other simple but efficient technology: Those who own the building and would front the capital costs are not the ones paying the electrical bills, and the ones paying the electrical bills (the tenants) would be sinking costs into real improvements which would then be owned by someone else. Except when the owner and the tenant are the same, or they have structured a lease to give each an incentive, anything with a high cost upfront is highly unlikely to catch on in commercial real estate no matter how attractive in the long run. Catch-22. Given how much energy is consumed by that sector, this is no small problem.


RE: it's about time
By rockyct on 2/14/2007 1:19:11 PM , Rating: 2
Almost all of the traffic lights in San Diego were replaced with LEDs around 2001-2003, yellow included. However, I have seen some traffic lights where sections of LEDs were out. It didn't seem like the bulbs burnt out, but rather something else failed. Perhaps corrosion on the LED leads? It seems like the fixture fails before the LEDs burn out, but that should improve with time.


RE: it's about time
By mindless1 on 2/14/2007 3:35:40 PM , Rating: 2
How can it "not seem" like the bulbs burnt out?

That's actually fairly common, when they're in series and driven too hard in a poor enclosure so they overheat. Those selling LED lighting are quick to point out best case specs, but sometimes not even all the specs are possible simultaneously. It can easily require more power than claimed for same usable light level, and light level only spec'd for initial "new" LEDs, not the degraded level from running them harder to attain a given light level.

I'm not against LED lighting at all, but it is a less efficient light than many fluorescents so in climate controlled areas the real argument isn't just how it compares to legacy lighting but whether it is really the best type for the proposed goal. In an outdoor parking area it might be ideal, if the lights are properly made. I Mean both types being compared, the picture posted here is deceiving as there shouldn't be a difference in amount of light, unless there were simply fewer or purposefully-lower rated non-LED fixtures.


RE: it's about time
By masher2 (blog) on 2/14/2007 3:40:31 PM , Rating: 2
> "How can it "not seem" like the bulbs burnt out?"

Probably because he noticed sections failing in patterns, as opposed to random bulbs failing.

> "the picture posted here is deceiving as there shouldn't be a difference in amount of light..."

Agreed...that photo is obviously a bit of marketing sleight-of-hand.


RE: it's about time
By digital batman on 2/14/2007 5:00:06 PM , Rating: 2
No, the picture shows what I was talking about as far as directional light...LEDs produce light and fire all of it down the barrel. Flourescents and sodium lights radiate, wasting some light i.e. some of the light being captured photographically is being lost as it is heading away from the camera which is not happening with the LED fixtures.


RE: it's about time
By digital batman on 2/14/2007 5:02:35 PM , Rating: 3
And quite possibly the fact that after the LED upgrade, there are quite a few more actual fixtures. :)


RE: it's about time
By rockyct on 2/14/2007 8:25:40 PM , Rating: 2
It was not a bulb here and a bulb there. It would be a clump of maybe 10 bulbs, then a smaller clump of 8, or even a large clump of a quarter of the entire lamp. The size of the clump of dead bulbs is not consistent or in an apparent pattern.

My point is that the quality of the entire fixture right now determines the life of LED fixtures. LED Christmas lights have a large problem with corrosion on the LED leads, especially with sets where the bulbs are not sealed. The actual LED bulbs can last 10 years, but other variables right now are limiting their life.


When..
By Tsuwamono on 2/14/2007 11:46:49 AM , Rating: 2
I used to work at a department store in highschool and i remember the only thing in the whole store that i found difficulty selling was LED christmas lights and the halogen bulbs.

However most people are cheap so i usually told them that with your regular Christmas lights your spending about 31$ a month to have 600 of them and most people have over 1000. However with the LED 600 lights can be lit for 45 cents... now thats a god damn good deal.

Anyone know the savings on a halogen bulb?




RE: When..
By glenn8 on 2/14/2007 11:53:39 AM , Rating: 3
"However with the LED 600 lights can be lit for 45 cents... "

45 cents/month? That is a damned good deal. Maybe I should convert my entire house to run on LEDs :)


RE: When..
By Hyperlite on 2/14/2007 11:54:56 AM , Rating: 2
ha yeah this is one bandwagon i have no inhibitions about jumping on. =D


RE: When..
By walk2k on 2/14/2007 1:36:49 PM , Rating: 2
They are more expensive but you'll get back 10 times what you pay up-front in energy cost savings. Plus you are doing your part to reduce climate change...

A while ago I replaced the halogen torch lamp in my living room - it used 150 watts on "low" (and 300 on high, but I never used that). I replaced it with a 3-way compact-flr. that uses **9 watts** on low! Now, the lamp was $15 (cheap but not bad, wood and glass, not plastic..) and the bulb was $10! (a "30-70-100" 3-way bulb, not cheap heh). But the regular 60-100w bulbs are much cheaper, you can get a 2-pack for $8-9. Plus, the power co. here recently had a promotion, they subsidised the blubs and sold them in 4-packs,"100w" bulbs, for $5. So $1.25 each, can't beat that.


RE: When..
By Samus on 2/14/2007 12:56:15 PM , Rating: 2
halogen isn't more efficient than incandecent, its just brighter and very natural. It can be dangerously hot. In Chicago, they've made halogen lights illegal in restaurants and bars for use outdoor (patio, streetfront eating, etc) because awnings were catching on fire.

led's dont emit much light though. xmas lights are a very practical application for them, because light isn't really needed, just a little.


RE: When..
By MrTeal on 2/14/2007 2:27:44 PM , Rating: 3
Regular lights won't cost $31 a month, unless you're painting 100W and stringing them from the trees.

Regular minibulbs are about 0.5W. 600 of them would use 0.3kW, if you ran them 24 hours a day at $0.10/kWhr, that's only $22. Who runs their lights 24 hours a day?

LED lights need about 1/10th the power of regular minilights, so they'd only cost $2.20 to run all day every day for a month.


thats really great
By senbassador on 2/14/2007 1:26:52 PM , Rating: 1
Thats really great, BUT, isn't a large proportion of our household energy usage goes into airconditioning? Like around 50% (I don't know the exact figure).

Unless you can somehow have airconditioners using LCD technology, you will only cut light usage. And then what about all our non-household use, such as farming? Then again LCD's also reduce heat production which would cut our airconditioning costs somewhat as well.

I am not knocking LCDs btw and I think they're great, just that they will only save a small proportion of our total energy.




RE: thats really great
By ahodge on 2/14/2007 1:49:28 PM , Rating: 2
Umm, LEDs?


RE: thats really great
By senbassador on 2/14/2007 6:17:33 PM , Rating: 2
yes, I meant LEDs. My bad.


RE: thats really great
By fic2 on 2/14/2007 5:13:02 PM , Rating: 2
There are more efficient A/C units out there. My brother lives in San Antonio and when they were remodeling their house the got a SEER 18 A/C unit. From what I understand this is 80% more efficient than a SEER 10. (I think SEER 12 is the lowest sold in the U.S.) Anyway, they bit the upfront cost of it and he said that everyone told them how stupid they were for paying so much more for a SEER 18. During the summer he said that their electric bill was never over $100 while their neighbors were paying over $300. At that rate it want take long to make it up.


RE: thats really great
By senbassador on 2/14/2007 6:21:01 PM , Rating: 2
hym, that sounds pretty cool. I would imagine everything eventually gets more energy efficient over time as the technology improves.


RE: thats really great
By masher2 (blog) on 2/15/2007 8:27:24 AM , Rating: 2
> "During the summer he said that their electric bill was never over $100 while their neighbors were paying over $300"

Then either his house is smaller or he didn't keep it as cool. Assume a $320 bill and 75% of your power usage from air conditioning. Then an 18 SEER unit will save you $106 over a SEER 10, cutting your bill to $204.

I'm a big fan of efficient heat pumps...I have SEER 16 units (the most efficient which could be bought when I built my home). But lets not overstate the benefits.


also
By Hyperlite on 2/14/2007 11:52:50 AM , Rating: 2
there is also the removal of cost of bulb replacement, both in labor and material. it won't go away, but it will be greatly diminished.




RE: also
By ajfink on 2/14/2007 12:09:49 PM , Rating: 4
Yeah, but even the cost of replacement and labor will initially be caught up. LEDs last for a very long time, too. Also, you can't put a price on bragging rights and a good conscience about environmental friendliness, :)


Reducing Energy Consumption
By KingstonU on 2/14/2007 3:42:32 PM , Rating: 2
One of the global problems is that our energy consumption levels are unsustainable, but this a step in the right direction as we increase efficiency. I was simply delighted to hear about the encouragement to use newer, more efficient technology in a city wide scale like this.

I was shocked to hear that people can preffer that dull, unatural
yellow haze from regular light bulbs to the cleaner, brighter white light from CFLs and LEDs. As for higher up front costs, if people could be less short-sighted they'd see how much cheaper these newer technologies are in the long run among a long list of other benefits.




RE: Reducing Energy Consumption
By masher2 (blog) on 2/14/2007 4:01:48 PM , Rating: 2
> "One of the global problems is that our energy consumption levels are unsustainable..."

I disagree. In fact, in a couple centuries, global energy consumption will be 10-100 times higher than it is today...and yet our food, water, and air will be cleaner and healthier than ever.


RE: Reducing Energy Consumption
By smitty3268 on 2/14/2007 7:49:36 PM , Rating: 2
You hope... We're certainly going to run out of oil at some point, but hopefully by then we'll have something to replace it. Fusion? Solar? Geothermal?

I agree air/water will probably end up getting better. No 1st world country would put up with some of the current conditions in poor countries caused by mining, etc. So as the rest of the world get richer pollution should decline.


Has anyone tried these LED lightbulbs?
By follick on 2/14/2007 3:34:03 PM , Rating: 2
Has anyone tried the LED lights from here:
http://www.dvnation.com/led-solid-state-lighting.h...

I was thinking about switching but the Lumen levels seem low.




By fic2 on 2/14/2007 5:29:51 PM , Rating: 2
What a joke of a comparison on their website. They have an energy comparison of replacing one 60W incandescent with a 2W LED. They don't mention anything about the lumen output of either. 60W I lumens is ~700 lumens, 2W LED is 31. So you would need at least 22 of the 2W LEDs to provide lumen equivalent. 22 2W LEDs at $35/each not to mention the type of fixture you would need....


LED's rock
By otispunkmeyer on 2/15/2007 3:55:31 AM , Rating: 2
i replaced all my tail and brake lights with LED ones...they are awesome, next i will be replacing all my cars indicators with LED ones too... just need to get the right resistance packs so that they actually work and blink at the correct speeds.

(Uk... orange indicators front and back)

i love how they are brighter than the normal 5/21w bulbs and come on and off instantly, and they are a great help in foggy conditions, the higher intensity can be seen much more clearly and from further away.

LED will eventually take over the HID xenon bulbs too




RE: LED's rock
By otispunkmeyer on 2/15/2007 4:35:36 AM , Rating: 2
i should mention that a 5/21watt twin filament bulb used in my car for tail/stop lights can be had for cheap around a couple of quid.

the two replacement LED bulbs i bought, that have about 20 odd individual automotive grade RED LED's on them each cost me £24 and they were one of the cheaper sets. so yeah the bastards aint cheap.

on the plus side, ill never have to worry about having a light out.


Brilliant
By Nik00117 on 2/14/2007 1:17:00 PM , Rating: 3
1. It costs less to light
2. The light is better
3. The light lasts longer

If I build a house i'll put LED lighting al throughout it.

I got a PC that is about 12 years old, the HDD light on it is still good. never had a normal light bulb even with light use last for 12 years.




nice
By Hyperlite on 2/14/2007 11:45:48 AM , Rating: 2
i am definitely beginning to <3 Raleigh. cool stuff.




Where is that deck?
By JTMoney1014 on 2/14/2007 12:08:47 PM , Rating: 2
Which deck is that? I wouldn't mind seeing it in person to see the difference.




Nice
By Scorpion on 2/14/2007 12:54:32 PM , Rating: 2
Wow, I'm shocked to see some politician taking the initiative on EFFICIENCY. Sure, there's a cost associated with changing anything, but it's more than recouped in the long run. LED's aren't succeptable(sp?) to just "going out". There is no filament, no fragile glass housing, and the manufacturing cost keeps decreasing. Not to mention the power efficiency itself.

I welcome Raleigh to the 21st Century. :)




good/bad
By walk2k on 2/14/2007 1:19:18 PM , Rating: 2
LEDs are good at projected light, like a traffic light/sign or tail/turn light on your car. They aren't very good at broadly illuminating an area or a room. I believe law will require US automakers to use all-LED lights on all new model cars some time in the near future. Not only do they use less energy, but they last virtually forever. I can't tell you how many BRAND NEW cars I see on the road with a tail-light out. I'm talking Lexus, Mercedes, BMW... Using LEDs will virtually eliminate this safety hazard.




Follow-up
By digital batman on 2/14/2007 4:16:37 PM , Rating: 2
And resellers can actually make different temperatures of white (as white LEDs that are strong enough for lighting spaces are sort of a hybrid-using phosphor on the casing to produce different temperatures). Pure white LEDs without additional means don't exist.




I Know LEDs Are More Effiicient
By qdemn7 on 2/14/2007 6:49:16 PM , Rating: 2
I bought a Lightwave 4000 LED flashlight 2 years ago. It's advertised as being able to run continuously for a full 30 days. I’m still on the first set of D batteries. Try that with a conventional flashlight.




Here in Portland too
By tk109 on 2/14/2007 9:08:44 PM , Rating: 2
Here in Portland Oregon they just lit one of the bridges tonight with it's new LED street lights. Instead of just lighting them on Holidays for this one bridge they are leaving them lit all year now. Since they save so much money using LED.





By SunAngel on 2/14/2007 12:55:03 PM , Rating: 1
In other news, case modders invade NC's underground raping and assimilating its residents into its' ideaology. First order of business was to alter the psychology of its new population to fend of the presence of fluorescent lights. Second order of business was to eliminate non-transparent surfaces removing complete visual densities.




"I'm an Internet expert too. It's all right to wire the industrial zone only, but there are many problems if other regions of the North are wired." -- North Korean Supreme Commander Kim Jong-il














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