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New York City Street Lights To Go LED
eldavojohn writes "Wired has a short piece on NYC's new street light project. I don't think we need to belabor the many benefits that LEDs hold over traditional light bulbs, but the finishing touches are being addressed, and they will hopefully be put into place sometime next year. This design won a competition back in 2004, and OVI has been whittling down the prototypes. At $1.175 million, this sounds like a pretty cheap deal considering the DOE forked over $21 million to 13 R&D projects along the same lines."
The thing that is awful about led lamps is that most of them are run straight off the AC voltage and have massive 100% brightness flickers. If you are moving it's like a strobe. You don't see it in car lights since they are run off DC. but most, perhaps not all, AC socket lamps I've seen have really bad flicker.
I also how they have secondary lenses since LED's can be very directional the way they are typically resin cast.
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EMP generators, anyone? How about Mooninite patterns?
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This is something I've been wondering about for awhile. LEDs (especially the white ones) are really bright for being so small, and they don't have that yellow tint that incandescent bulbs do. Compact florescent bulbs are nice, but they aren't perfect for every situation. I'm not an expert on the subject, but I've always wondered why they don't make giant LEDs that can replace ordinary light bulbs. It seems like 220 AC would be more than enough to power them.
"It is a denial of justice not to stretch out a helping hand to the fallen; that is the common right of humanity."
there is no way they can change all the lights for one million.
many NewYorkers does it take now to change a light bulb?
"New York City Street Lights To Go LED on Friday December 19, @11:15PM"
Well, that's pretty quick work.
Dammit Man, you gave away the plan!
It's not to cause crashes, just to make drivers swerve so that they can be pulled over and ticketed or searched for that 0.00001 microgram of coke on every dollar bill in circulation.
No swerve, no probable cause. Means the ter'ists can just run rampant and kill us all. /sarcasm
Aren't LEDs less efficient for white light, compared to current streetlights with HPS? Wikipedia says 150 lumens/watt for HPS and only 10-90 for white LEDs.
http://en.wikipedia.org/wiki/Luminous_efficacy
Are there any major observatories near NYC? (hmm large mountains close to NYC?)
Are these new lights narrow or wide spectrum?
See: http://en.wikipedia.org/wiki/Light_pollution
Because of prior experience in LED street light projects, they would be a natural.
Blue Light hazard? No wonder my eyes hurt after shopping at K-Mart.
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The lighting product manufacturers quote efficiency in lumens-per-watt(lpw). What they don't shove in your face in marketing is that the devil is in the details.
CFLs, LEDs, incandescents, HPS and metal halides all have drastically different spectrum outputs. Incandescents have a very broad spectrum but their lpw is astonishingly low.
CFLs have as much as 80 lpw, whereas MH and LEDs are currently at about 100 and HPS can be even higher(around 140 lpw initial, which declines over time). LEDs have the potential to be higher than HPS but across the lifetime of the HPS bulb the LED may end up with a higher average lpw and definitely much longer service life.
There are CFL's with a broader spectrum but they're less efficient. While not completely monochromatic, there is a big spectrum spike in reds and yellows for HPS bulbs. Most people find this light to be soothing. Metal halides have a broader spectrum than HPS but are less efficient than even fluorescents. There are new white LEDs in research that produce as much as 145 lpw, but these are not commercially produced yet. Philips produces a 115 lpw white LED which is available in large quantities. You're right about the blue light hazard though - phosphor based white LEDs have a large spike around 465nm.
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You can't legislate goodness. Let each to his own destiny, by will of his freely made choices.
$1.175 million sounds way too low to me. That probably wouldn't cover the light poles, LEDs, or installation, let alone replacing all the thousands of existing light poles.
Here in Portland, OR, we have already started to use LED street lights. And now that we're in a snow storm, these lights aren't working. LEDs don't produce heat (that's why they're efficient). By not producing heat, they don't melt the snow away from them. So all the LED streetlights in Portland are covered in snow and cannot be seen.
The old lights produce enough heat to melt all the snow. Snow in Portland is rare, so it's not that big of a deal. In NY, it's quite the opposite.
I did a "thorough skimming" of every link, and I see no mention of light pollution or dark sky lighting?
WTF?!?! Somebody please tell me I missed it.
Operator, give me the number for 911!
it to you pal?
(Posting this because you missed out on the subject/comment flow...)
I feel fantastic, and I'm still alive.
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I have two dongs.
The Department of Transport in South Australia begun a migration to LED powered traffic lights and you should see some of the graphs they've got. MASSIVE reduction in power use.
Your sig's link appears to be broken.
They're not proper street lights if they don't.
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Perhaps this is OT, but I honestly don't know. One thing in my area that is driving me literally ape shit is the new installation of what I assume are energy efficient stop lights (LED?). What kills me is that they are barely visible unless you are looking dead on from the right angle. It reminds me of old passive matrix LCDs. They are simply maddening and they are popping up all over the Minneapolis/St. Paul area. I don't understand what the benefit to lights that no one can see are. They seem quite dangerous. In fact even when looking head on at them they are quite dim, and often hard to make out from a distance. If anybody can tell me what the hell they are and why they are around I would be really stoked.
Im from a city in Canada and we had to replace a bunch of LED lights cause they didn't create enough heat to melt the little bit of snow that blows into them.
We just had a snow storm in Portland Oregon and there was a problem with the LED traffic lights not melting the snow, so people couldn't see the lights.
Personally I'd miss sodium vapor street lights if LED replacements became fashionable. Perhaps it is a romantic notion, but it seems to be that one of the reasons sodium lamps have become so popular is that the orange light they emit is reminiscent of fire, and in colder northern climates their warm glow is comforting to people at some deep instinctual level.
"I bless every day that I continue to live, for every day is pure profit."
We've had LED signals here in Osaka for 5+ years how and they work very well. Here are some links (in Japanese) with photos showing what they look like:
Red Light, Green Arrow
Pedestrian Crossing
Green, Amber, Red (the amber is actually brighter than it seems in this photo)
I haven't experienced any problems with them and I drive daily here. There is no noticeable flicker and they are a lot brighter than the traditional signals they replaced.
Some people are like slinkies--basically useless but they bring a smile to your face when pushed down the stairs.
I just hope that they invest in better LED technology and higher quality control standards than when NYC rolled out the LED based crosswalk signs for pedestrians, the ones with the orange hand and white walking figure.
Throughout the city you can see quite a few of these signs failing in sometimes very spectacular fashion, such as displaying both the hand and the walker at the same time blinking or solid. Other times multiple LEDs have become non-functional and the patterns have changed to comical designs with various fingers missing from the stop hand or body parts missing from the walking figure. I've seen tons of these broken signs but still I'm missing that elusive middle-finger gesture.
One thing that the city did very well is the progressive upgrade of the intersection lights (red, yellow, green) to LEDs. The started off with changing out only the green lights and after the change you noticed right away the super bright new green light at the intersection. At certain times of the evening the new green LEDs are so bright that is almost hurts to look at them directly, but I don't know if this is a physical thing with the human eve being more sensitive to green or with power fluctuations at that time of the day.
After the green light change they changed out the red lights and lastly they did the yellow lights. Since the changes I've seen a number of intersection lights be burnt out or non-functional and I have called them into the new consolidated city wide services line at phone number 311 and the city came and replaced them in a day or two. The failure rate for the intersection lights is a lot lower than for the crosswalk signs, and that's a great thing since the city has many more crazy dangerous drivers than insane pedestrians as it is.
Let's hope the use high quality LEDs and electronics in these new street lights.
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all you need is a crayon.
...if every home in the US replaced their five most-used bulbs with CFL's, the energy and greenhouse gas savings would equal taking 8-million cars off the road. The numbers from replacing every street light in a city of 9m people could be just overwhelming. So let's do it nationwide. Now!
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1.175 million dollars to figure out how to make street lamps work with LEDs? Maybe if I had the same government connections I could get a nice cushion too... If the DOE R&D is anything like the rest of the American Government, it's spent on vapor, and probably unaccounted for just like the rest of the spent tax-payers money spent on things that don't exist.
Well on the positive side, atleast LEDs exist... I think...
LED traffic lights are popping up here in the UK, too. I have to agree they do not always make a good substitute for the old incandescent bulbs.
Usually with LED traffic lights unless you're looking at them dead-on they don't shine very bright, and when you get in the line of sight of some they're almost blindingly bright even from a long distance away, day or night.
Didn't anyone actually do any real world tests of these things, or at least get some opinions of regular drivers? Unbelievable!
To do something right, you often have to roll up your sleeves and get busy.
Here's a link to a story regarding the Crosswalk Sign replacements in NYC to the new LED signs. Includes pictures.
Social Design Notes - Crosswalk Usability - 2004-04-08
This is just great. In NYC right now, they're cutting the city budget, implementing a whole slew of new taxes (taxing Itunes store purchases?), cutting subway service (while hiking the rates)... and what are they spending the money on? That's right, replacing street lights with LED bulbs. Aren't there a little more important things to worry about/spend money on right now?
I'm not one of those wacky conservative nuts but here in NY, we're about to be forced to pay all new kinds of taxes on various things such as Non Diet, Soft Drinks.
I'm all for the LED's if they're better in the long run and cheaper than maintaining the current lights but is it necessary right now?
Our politics are all screwed up here in NY. Its the blind leading the blind... literally.
Monochromatic lighting is somewhat dangerous since details don't stand out as well. A full spectrum light would be much better. However, prior to LEDs, there wasn't a good choice since you need a light that is efficient, long lasting, and durable. So LEDs not only are nice, but it really is much safer. The larger spectrum yields better detail and thus drivers able to better react to their environment.
Then it is psychosomatic, not real. Cars are DC systems, not AC. It would be rather stupid to go through the trouble to take that DC and convert it in to AC just for the tail lights.
This doesn't surprise me, as I've found a number of the "I can see flicker," people have it mostly in their head. A former coworker had a wife like that. I've no doubt she was more sensitive than the average person, but most of her problems were in her head. She complained she couldn't stay in our office long because of the flicker of the lights... Except I checked, our overheads were powered by electronic ballasts that operated in the 30kHz range. So she wasn't seeing flicker, she was seeing florescents and assuming they were flickering.
At any rate automobiles are DC powered. Check one with a multimetre if you don't believe me. Thus they are not going to be pulsing their lights.
You're not buying the right kind of LED traffic lights. I remember a couple "too bright head on, can't tell off from on from an angle" lights, but nowadays they're all really nice.
"We don't need to belabour the advantages of LEDs over traditional lightbulbs"?
Actually, we do, since we've had lightbulbs other than incandecent for over a decade, and incandecents are never used to light streets. LEDs manage about 100 lumens per watt, similar to high pressure sodium lamps. The old orange low-pressure sodium lamps are still king of the hill at 200 lumens per watt.
So what were those advantages again? Compared to high-pressure sodium lsmps, they're the same efficiency and lifetime, but a lot more expensive. The only advantage to low pressure lamps is colour, but they loose a factor of 2 on efficiency.
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Oh boy, do I agree. Ever since they replaced the traffic lights with LEDs at Dupont Circle in Washington, DC, drivers can see the state of the light (red, green) only at the very last second, creating a major hazard for both other drivers and pedestrians. Honestly, didn't anyone do field tests before installing these?
I am all for energy-saving technology, but a traffic circle is not the best place to install it.
Another problem is how well they handle fog and rain. Current streetlamps are chosen because the wavelengths they produce penetrate fog very well. If you've a light that doesn't penetrate fog, just gets reflected, it's a complete utter nightmare as you're illuminating the fog and making it even harder to see.
[...] Instead, they keep selling us a tiny wire the size of a pubic hair [...]
Please adopt the metric system. PLEASE!!!
...of why I'm glad I got out of Electrical/Computer Engineering.
You need to look at the LED taillights on a Cadillac in moving traffic. In the dim mode used for tail/marker lights (not the full brightness mode used when the driver presses on the brake pedal), the taillights are being dimmed by PWM with no filtering. The flicker is extremely annoying and gives a strobe-like appearance where your eyes see multiple images of the lights in moving traffic.
Why Cadillac chose to dim their LED taillights this way is beyond explanation. It makes the cars look cheap, but it can't be a cost saving, because you can dim an LED array with a simple resistor and eliminate the PWM circuit altogether. LED taillights for heavy trucks use a diode and a resistor for the lower light output level and they look great.
The effect is more noticeable when you're traveling at a different speed than the Cadillac, or if you move your head side to side while looking at the taillights. It's really obvious and undeniable.
Putting moderation advice in your
[...] Instead, they keep selling us a tiny wire the size of a pubic hair [...]
Please adopt the metric system. PLEASE!!!
Pray tell, can you enlighten us to what the metric equivalent of a pubic hair is?
5.3 centicurlies?
Putting moderation advice in your
Here is a couple of points on LEDs.
1. The light is polarised, this has shown to be an advantage in that polarised light penetrates fog and mist more. It may make it easier to filter out for reducing light pollution?
2. The LED light wavelengths are narrow. This makes shadows sharper and the details in a rough surface look more intense. They also have a much narrower angle of view than other light sources.
3. White LEDs are not really producing true white. It's much more blue. Its a human eye reaction to the type of light.
I tried replacing my household CF bulbs with daylight bulbs and boy did the rest of the street notice my house! At night I could see the more natural white light windows of my house for a long way away. They really stand out.
The detail of surfaces looks much more intense and real. The dirt and unevenness of paint stood out more.
Of course this could have been a physiological POV due to the newness of the scene.
Wife said I had to change them back to normal CF lights!
No doubt this same effect will be felt by the public but will fade as more streets get converted. But expect public resistance. People will not like walking down alternatively coloured lit streets.
I imagine if a street had LED white light then the councils could be asked to clean up the street more! People will certainly notice their state.
One street in Edinburgh uses daylight coloured (~8,000K) lamps at night and it really looks and feels like you're under a shaded tent during the day even though it's 2am! A little surreal when you come out of a Pub I can tell you! :-)
LEDs street lighting will take some getting used to by the public.
I suspect it will reduce criminal activity, at least initially.
Stuart http://stuarthalliday.com/
How much enery and contamination is needed to manufacture and recycle LED lights, versus the same costs for traditional sodium lamps? In terms of contamination, I believe the whole lifecycle should be considered, not just energy consumption while operating.
Claiming you can hear a sound a few kHz above the 'average' human range is one thing, as is claiming to be able to see a 70 or 85 hz flicker. But when you start claiming that you can hear the tectonic plates shifting, or see the flicker from a 1.5 kHz strobe light, it's beyond 'everybody is different' into 'I'm a comic-book superhero' land.
Have you been touched by his noodly appendage?
In fact that is exactly how they are designed. But they still are off about 20% of the time during the cross-over
Some drink at the fountain of knowledge. Others just gargle.
Over the course of two to three years, this will actually save money. Just like the replacement of traffic signals with LEDs, it's going to cost less to go to a new system than to keep using the old.
Have you been touched by his noodly appendage?
I cross the (UK) West Coast Main Line every day, by way of a foot crossing. There's no lighting there at all, except for the little red and green stop/go lights of the crossing itself.
At night, I have to shield my eyes from the green light so that I can actually see the gate to open it. Once on the crossing, you can see the green lighting up the bushes on the other side, and you see the opposite gate black against that green. That's the only way (other than knowing that you've got to walk at 90 degrees to the railway) that you can find your way over.
There aren't many better cures for constipation than being half-way across, the sirens starting, and the lights going red - especially as it goes almost completely dark when the green lights go out. Now you're on a railway, with a Pendolino coming at you at 125mph, and you can't see the gate to get out, let alone see the hinge so you know which side of it to push. Even after two years of using this crossing, that momentary panic can make me forget which way the gate works - I've even been known to pull it rather than push it.
Network Rail think this is OK. (I've complained like hell and they've done nothing.) If it were me, I'd have luminous "Exit" signs on the back of the gates.
But yes - green LEDs are way brighter than red ones.
Call your local authorities and ask them how much installing a simple on/off streetlight would cost per year, say, like if your local street corner needed one.
You will be shocked, figuratively. Probably good for the environment, but the cost of the lights, including the electricity, pales in comparison.
Hopefully they'll be white or near white LED lights since I cannot stand that ugly orange cast of the HPS lights.
A couple of years ago I was driving in Maine during a snowstorm. The yellow and green light bulbs were clear, but the red ones, apparently LED bulbs (I was told that), were totally covered with windblown snow. A dangerous situation. I was told they don't produce enough heat to melt the snow off them. I suggested little heaters for them. Think about it...
The best LEDs now available for street lighting get only 115 lm/W, while Low Pressure Sodium can get up to 200 lm/W. So this system will use more, not less, energy. The only advantage of LEDs then would be increased lifetime of the bulbs. (Sodium bulbs also probably decrease in efficiency over their lifetime, while LED output remains relatively constant.)
I've abandoned my search for truth; now I'm just looking for some useful delusions.
I always thought that the sodium lights were the best for not creating light pollution which would interfere with space observations, etc.
How do LEDs stack up?
A fool throws a stone into a well and a thousand sages can not remove it.
Here in Tucson we've had (some) LED traffic control lamps for a while, at least a year. I find it terribly hard to believe that we're on the leading edge of this technology. Many of our emergency response code lights are LED, though mostly on newer vehicles (/i.e./, no retrofit code-packages). Again, this can't be new, nor news.
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The City of Raleigh has been partnered with Cree for over a year in rolling out LED lighting for parking structures and streets.
http://www.cree.com/press/press_detail.asp?i=1171295242023
Chip H.
"It's also worth noting that some people don't like the light spectrum output on white LED's. Personally, I prefer the pink tint from high pressure sodium lamps"
We're moving into a global financial credit crisis. Alas I think the aesthetics of which colour street lights we prefer will take second place to which will be cheaper to run in the long term.
Please remove the Shuji Nakamura tags. Nakamura improved reliability of blue GaN lasers and LEDs. He did not even work on red, yellow, green LEDs which do not use GaN.
I don't know of anywhere that uses incandescent bulbs for street lighting anymore. How efficient are LEDs compared to sodium or mercury vapor fluorescents which are currently used?
What about home lighting? Are120v screw in bulbs available for a reasonable price yet? You can buy CFLs in the 800-1000 lumen power for less that $2 apiece...
Unlike older technologies LEDs are very tolerant of power cycling, so how long will be before every street light turns on or off only when it needs to?
...lb
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LPS looks ugly but is sufficient for street lighting, and at 180+ lumens per Watt, LEDs have quite a bit of catching up.
"Politicians and diapers must be changed often, and for the same reason."
CFL and HPS do not have a narrow spectrum; they have a spiky spectrum. White LEDs have a two-humped spectrum. The narrow bands of the individual spikes means it's impossible to filter them effectively to try to match sunlight; you can only do this with the blackbody spectrum of an incandescent light (in the case of the white LED, most of the power is in the blue hump so filtering that would reduce efficiency by a large factor).
"Politicians and diapers must be changed often, and for the same reason."
According to the DOE, LPS caps out at about 150 lpw. This is a hair more efficient than HPS, but at a reduced bulb lifetime and dramatically poorer color rendition.
I would certainly like to see street lamps move from LPS to HPS for longer service life and improved color spectrum.
You can't legislate goodness. Let each to his own destiny, by will of his freely made choices.
Sunlight is between 5500K and 6500K on a regular day even as high as 8000 or 10000K if its cloudy. White LEDs are usually in the 6000K range on color output, so (other than the flicker) I think it would just take a little getting used to and then you wouldn't notice it at all anymore. I think that we are used to the yellow tint of lights just because thats what we have grown up with, but in nature that light exists only at sunrise/sunset and if something is on fire. Just my $.02
There is this new invention called a "diffusor lens". You should try it sometime.
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Considering that LED-based traffic lights have been around for years and don't need to be prototyped, that amount sounds quite expensive.
Your DOE reference is shit, as is clearly demonstrated by a counterexample that took all of five seconds to find: http://www.prolighting.com/sox180.html
30000 / 180 ~= 167
The highest I've seen was 190 a couple of years ago.
Moreover, the lifetime is only 50% higher for HPS.
"Politicians and diapers must be changed often, and for the same reason."
http://dansdata.blogsome.com/2008/12/27/led-street-lighting-not-as-good-as-you-think/ this is greenwash. the numbers dont work. add the cost of upgrading and its just tax payer money funneled to a special interest