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New York City Street Lights To Go LED 303

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."
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New York City Street Lights To Go LED

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  • flicker crashes (Score:5, Interesting)

    by goombah99 ( 560566 ) on Saturday December 20, 2008 @12:20AM (#26181331)

    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.

    • Re:flicker crashes (Score:5, Interesting)

      by digitalunity ( 19107 ) <digitalunity AT yahoo DOT com> on Saturday December 20, 2008 @12:30AM (#26181401) Homepage

      Assuming the line voltage is run through a full wave bridge rectifier, there would be a 120 Hz flicker, imperceptible to most people. Toss a large capacitor across that DC output and you've got dramatically less ripple.

      Your directionality comment is apropos. 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.

      • Re:flicker crashes (Score:4, Insightful)

        by goombah99 ( 560566 ) on Saturday December 20, 2008 @12:34AM (#26181435)

        Assuming the line voltage is run through a full wave bridge rectifier, there would be a 120 Hz flicker, imperceptible to most people. Toss a large capacitor across that DC output and you've got dramatically less ripple.

        true but then you also have 100 times the surge current when you turn them on, or a slow turn on.

        What you say is of course obvious to any EE, and yet i've never actually seen a single 120v LED lamp made that way. One wonders why.

        • Re:flicker crashes (Score:4, Insightful)

          by digitalunity ( 19107 ) <digitalunity AT yahoo DOT com> on Saturday December 20, 2008 @01:20AM (#26181697) Homepage

          These aren't headlights, they're street lamps. Do you really care if it takes them 3 minutes to warm up?

          And even assuming they have ballasts featuring accelerated warm-up, the starting current will still be as much as double the normal operating current requirements. Really though, the starting current is negligible in the grand scheme of efficiency comparisons.

          I'm not an expert on line voltage LED units designed to replace incandescents, but I would imagine including a bridge rectifier and capacitor would increase the cost and pose significant design constraints due to the components size.

        • Re: (Score:3, Interesting)

          by Gordonjcp ( 186804 )

          What you say is of course obvious to any EE, and yet i've never actually seen a single 120v LED lamp made that way. One wonders why.

          I actually have a broken LED GU10 lamp on my bench at the moment. Inside is a small bridge rectifier, a smoothing capacitor and a tiny chopper PSU. The LED string is run at around 50D. The bridge rectifier and capacitor provide around 340V (240V mains) with about 10% ripple, but the chopper compensates for this and provides a 60kHz pulse-width modulated supply which is then

      • I personally get nauseous from any perceivable flicker and am very sensitive too it. I only last about 5 minutes in regular florescent lighting.

        I know that I am ultra sensitive but there are many people with various degrees of sensitivity to such flicker.

        I also dislike pure white light. It is uncomfortable to look at anything in pure white light.

        LED is a great technology but despirately needs to develop natural light replacements and/or incandescent replacements. A couple million years of evolution has t

    • Re:flicker crashes (Score:5, Informative)

      by amRadioHed ( 463061 ) on Saturday December 20, 2008 @12:37AM (#26181449)

      There are plenty of LED traffic lights around me and I've never noticed any flicker. I imagine it isn't a problem.

      • Re: (Score:2, Insightful)

        by RSCruiser ( 968696 )

        I don't notice any flicker as well. I have noticed that some lights have blocks of LEDs failing rather quickly after installation though. Entire sections of turn arrows and squares in circular lights that have gone out look rather weird. It may be a brand/manufacturer issue though since I see this in the larger metro area but not in the suburb where I live even though the suburb has had them longer.

        Makes you wonder if they'll have the same issues with chunks failing in these lights.

      • Re:flicker crashes (Score:4, Informative)

        by a1englishman ( 209505 ) on Saturday December 20, 2008 @02:43AM (#26182087) Journal

        The biggest problem with LED traffic lights is that the greens are REALLY bright. You'll be shocked, especially at night how bright the damned things are. In SoCal, we have LED traffic lights everywhere.

        • Re:flicker crashes (Score:4, Interesting)

          by gfilion ( 80497 ) on Saturday December 20, 2008 @09:07AM (#26183265) Homepage

          In SoCal, we have LED traffic lights everywhere.

          In Québec we have them pretty much everywhere too. Sometimes when the snow is just the right consistency and falls in the right direction, it sticks to the traffic lights lenses, obscuring them. In the past, the heat generated by the incandescent bulbs would melt the snow, but the new LED lights don't produce enough heat. A city worker has to remove the snow with a kind of small broom attached to a long pole.

          Two steps forward, one step back...

        • Re: (Score:3, Informative)

          by Tycho ( 11893 )

          Older LED traffic signal conversions probably replaced the old incandescent bulbs and color filters with LED panels made of LEDs using the appropriate color. They also in some cases may have used separate AC to DC converters located either in the control box for the traffic signal which would have been on the ground near the signal. Potentially this also meant rewiring all of the lights on each pole and replacing more equipment when required. On the other hand, an AC-DC converter could have been in each

      • No flicker here either (in London). The oddest thing about the change as far as I was concerned was the instant on/off of the lights. You don't really think about how long it takes for incandescents to fade, however when I first saw an LED traffic light something struck me as wrong and it took me a while to work out what.

        • Mod me down - I'm an idiot. I am talking about traffic lights, you're all talking about streetlights.

        • No flicker here either (in London).

          Nor here in Glasgow. What I have noticed - particularly on the amber traffic lights, because of the flashing amber phase - is that when they go off they blink out, then come back on and fade out from full brightness. I don't know why they do that - a bug in the firmware?

          I've noticed that the LED tail lights fitted to all the buses now come in two types, that either go on and off instantly or on newer vehicles, they have a slight fade when they go off. Again, a Small M

    • Instead of what sounds like raw-rectified power, they should have some intelligent (and too fast to see) flicker. Since LEDs could easily handled modulated power to send a data stream of something...

      hmmm... car tail lights could too, but what to say?

    • LEDs for this sort of light would be surface-mount - it makes automated assembly possible. And thus they would not generally have the hemispherical plastic dome you're used to from the leaded components. They'd probably just have a transparent coating that would not bend the light much.
    • Re:flicker crashes (Score:5, Informative)

      by Low Ranked Craig ( 1327799 ) on Saturday December 20, 2008 @01:55AM (#26181897)

      Well, they have been testing these lights in my home town of Scottsdale, and they have three different types installed along one stretch of road way. They are super bright, and there is no flicker whatsoever.

      The fact that they are directional is an advantage in this case since they are meant to throw light in a cone shape. The ones I've seen have no secondary lens. If there is any covering at all it is completely transparent glass.

      Personally I like them because the light is white, not the orange of sodium vapor. Reminds me of when I was a kid before the move from mercury vapor to sodium vapor...

      • 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.

        • Re: (Score:3, Informative)

          by Alex Belits ( 437 ) *

          LEDs only produce light in narrow bands of spectrum, so even if those bands are far apart, so the light looks white, the reflection from various materials may look nothing like the color seen under wide-spectrum source such as sun, incandescent or mercury vapor light.

          • Re: (Score:3, Informative)

            by imsabbel ( 611519 )

            Mercury vapour is MUCH worse than led in terms of "spiky spectrum". They nearly have no continuum at all. LEDs do.

          • Re: (Score:3, Informative)

            by Whillowhim ( 1408725 )
            Incorrect when talking about LEDs. "White" LEDs are covered with a phosphor that takes a blue LED's light and shifts it down. The output from the phosphor is broad spectrum, even if the original LED was a narrow band blue. Thus, these LEDs are a good wide spectrum light, instead of an approximation made from mixing red, green and blue LEDs. Of course, the problem you described can exist, but is commonly seen only with fluorescent bulbs.
  • by pwizard2 ( 920421 ) on Saturday December 20, 2008 @12:23AM (#26181345)
    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.
    • Re: (Score:2, Informative)

      by Anonymous Coward

      It's being worked on. Basically the issue holding them back is cost/brightness. Given the inevitable lowering of costs of all things technological and the toxicity of CF-bulbs I think it's just a matter of a few years before LEDs take on the consumer lightbulb market in a big way.

    • by goombah99 ( 560566 ) on Saturday December 20, 2008 @12:28AM (#26181387)

      uh... because they do and you can buy them [].

      • Re: (Score:3, Interesting)

        by Anonymous Coward

        That's not what he means. The replacement 120v led lamps are a collection of a bunch of little white led's. Why can't they make a single led the size of a lightbulb instead of 100 small led's.

        Is it possible to make a single, huge led?

    • Re: (Score:3, Informative)

      The white LEDS are doped to generate three distinct colors of light (R,G,B) whose combination yield a very cold blueshifted white light (>6500 K). If one seeks to use these for video, better check to see if the camera works well with such light.

      • by dgatwood ( 11270 ) on Saturday December 20, 2008 @01:06AM (#26181609) Homepage Journal

        Yeah. I've noticed that. What I don't get is why they choose to set the color temperature that way. Red LEDs are extremely cheap compared with producing light at the other end of the spectrum. Why in the world would they balance them towards the blue (expensive) end of the spectrum when that is both more expensive and visually unpleasant? About the only thing I can imagine about the current LED designs is that they were designed to be used in combination with standard incandescent bulbs. If you blend the two, you should get a fairly nice looking light spectrum, albeit probably a bit heavy in the yellows....

        I'd buy LED lights instantly if they actually used three emitters. Unfortunately, most don't. They use two---one yellow, one blue. Because the yellow LED has a relatively narrow light spectrum compared with an incandescent, you end up with basically no light output down near the bottom of the visual spectrum. The result is light that is downright unpleasant to deal with in every way. The bluish light makes it hard to see color accurately, makes colors not reproduce well in photography or video, and really isn't good for you mood-wise. Basically, the current crop of LED lights have all the problems of CFLs except the mercury (well, and the LEDs should last a lot longer, I believe).

        The question, then, becomes this: "When are we going to see properly designed white LED bulbs?"

        On the other hand, while they suck for homes, the existing LED lights are perfect for street lights. First, there was one experiment [] that suggests that suicides and crime may decrease when street lights are replaced with bluish lighting. Second, the color temperature of blue LEDs are virtually indistinguishable from the mercury vapor lights (~6000K) that are already used in a lot of places.

        • Re: (Score:3, Informative)

          by Bo'Bob'O ( 95398 )

          The company I work for has actually done a good amount of research on the technologies available for high efficiency lighting right now and they do indeed make warmer white LEDs. They look pretty nice and have an adequate CRI, however, their efficacy is poor enough compared to the cool white LEDs that they are in fact only about as efficient as compact florescent.

          I think it has to do with the fact that the visible light generating part of white (and blue) LEDs are phosphors pumped by what is actually a ultr

          • Re: (Score:3, Insightful)

            by dgatwood ( 11270 )

            Could be, but an LED that uses phosphors eliminates any interest in my book because it means the color spectrum is a spiky mess.... :-) Either way, though, I'd gladly accept much less efficiency to get better light quality. I hate CFLs (even the so-called daylight CFLs) so much that I'm planning to start stockpiling incandescent bulbs soon in preparation for the U.S. ban on them. That cold, lifeless lighting just really bugs me.

            • Could be, but an LED that uses phosphors eliminates any interest in my book because it means the color spectrum is a spiky mess.... :-)

              That is the way all white LEDs work.
              If you want something else, you will need an RGB array of leds - those exist too, but they cost more to manufacture and can't always be used to substitute for incandescent since some applications require a single point source.

              • by dgatwood ( 11270 )

                You can always put a more than one LED emitter in a single epoxy package. Tricolor LEDs are a red and green emitter inside a single clear shell. Those are at least as close to a point source as you'll ever get with a glowing filament....

            • by eggnoglatte ( 1047660 ) on Saturday December 20, 2008 @06:36AM (#26182787)

              First, the GP is right: most high power white LEDs are actually blue or UV LEDs with a yellow phosphor in the plastic packaging.

              As for phosphors yielding a spiky mess for a spectrum: how exactly do you imagine the spectrum of an RGB LED looks? The individual primaries in such combinations are VERY narrow band, so rather than a continuous spectrum you get three distinct peaks. Phosphors are actually smoother by comparison.

        • there was one experiment [] that suggests that suicides and crime may decrease when street lights are replaced with bluish lighting.

          What's the theory behind that?
        • Re: (Score:3, Interesting)

          White LED phosphors are blue-heavy with a yellow peak.
          People build them that way because they're cheap.
          Now that everyone's getting pissed because they look cheap, any LED module designer worth twenty cents is designing systems that have roughly 3 white to 2 red LED's to bring the spectrum down.
          However, every lighting designer I've talked to, when we suggest making multiple color LED fixtures, especially ones with adjustable color spectra, say "the customers *say* they want that but they won't pay for it."

    • by dlenmn ( 145080 ) on Saturday December 20, 2008 @12:43AM (#26181481)

      LED light bulbs do exist (they're a bunch of small LEDs, not one jumbo one -- I don't know if that's feasible).

      I think you hit on the problem in your post though, power. 220V (or 120V) AC certainly has enough watts, but it's not in a usable form for LEDs. They require direct current (DC) at a much lower voltage. So you need some power conversion electronics to make them work. Then, to make them work efficiently, you need more electronics to regulate the current through them. For a standard electronics project, you just use a resistor, but then you're wasting power (to the tune of P=R*I^2). Off the shelf components that regulate the power more efficiently exist, but it adds expense.

      Fluorescent lights need some electronics to work too, but I don't think they're as complicated (and are thus, cheaper). Cost is a big factor here, because old incandescent light bulbs don't cost much to purchase.

      • Re: (Score:2, Informative)

        The type of power supply used in LED lighting is called a 'buck/boost' converter. It is a switching supply that merely PWM's the filtered line voltage down at high frequency (40~60KHz) to the operating voltage and current of the load The difference between this and a standard switching supply is that no isolated secondary circuit is required and thus the only 'large' components are the rectified line voltage filter caps, load filter caps, choke and heatsink mounted FETs or IGBT's. This also neatly eliminate

  • How (Score:5, Funny)

    by no-body ( 127863 ) on Saturday December 20, 2008 @12:34AM (#26181433)
    many NewYorkers does it take now to change a light bulb?
  • by pentalive ( 449155 ) on Saturday December 20, 2008 @12:49AM (#26181517) Journal

    Are there any major observatories near NYC? (hmm large mountains close to NYC?)

    Are these new lights narrow or wide spectrum?

    See: []


    • Re: (Score:3, Interesting)

      by hardburn ( 141468 )

      NYC is a lost cause as far as astronomy is concerned, but I have hope that smaller cities and towns will see this and adopt it. LEDs are inheirently directional, whereas most fixtures tend to waste a lot of their light going out and up. So LEDs should be a win for astronomy.

      • Re: (Score:3, Interesting)

        by adamjaskie ( 310474 )
        LPS/SOX is better, really; the spectrum of LEDs is pretty intrusive to observations. LPS/SOX is also more efficient IIRC, but the bulbs don't last anywhere near as long.
    • by Animats ( 122034 )

      No, there are no major visual observatories near NYC. The nearest serious research telescopes are near Ithaca. Some closer schools have observatories, but they're training or hobby facilities.

  • by Anonymous Coward on Saturday December 20, 2008 @01:17AM (#26181683)

    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.

    • So you put a small motor in the lamp head that vibrates the snow off, similar to how a cellphone vibrates. You still make out like a bandit on energy savings.

      • Which would do exactly nothing to get the encrusted snow and ice to go away. You have to either heat them or use those tiny windshield wipers on the headlamps that some expensive cars have.
    • by Jah-Wren Ryel ( 80510 ) on Saturday December 20, 2008 @03:33AM (#26182287)

      So all the LED streetlights in Portland are covered in snow and cannot be seen.

      Since LEDs are more efficient (more lumens per watt) the colder their tmperature, you can at least take comfort in the fact those snow-encrusted street-lamps are very efficiently lighting up the inside of the snow.

    • Off-topic, but I used to do the 401 Montreal-Toronto 6-hour trip in winter fairly often. There were a few very scary times where headlights only reflected the snow back, so people turned on the 4 way flashers to get at least a periodic glimpse of where they were going.

      That was back when I was young and "invincible", it scares me today to think I did that with my then wife in the car (much of the trips were basically controlled sliding requiring great reflexes).

      The truckers on that route were heroes, slo
    • [The new LED lights don't melt the snow.] 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.

      Simple: install heaters whose wattage is the difference between the old and new lights.

    • Oh, I'm pretty sure they'll build some tiny heaters into it as well to melt the snow. Due to a mechanical glitch, you won't be able to turn them off in Summer, but hey, that way nobody needs to remember to turn them on again when the snow comes!

      We gotta save money. No matter the cost.

    • by hab136 ( 30884 )

      So all the LED streetlights in Portland are covered in snow and cannot be seen.

      How does snow get on to the bottom of the street lamp? What exactly *are* you guys smoking out there?

    • Re: (Score:3, Insightful)

      by An dochasac ( 591582 )
      This is really interesting. Until I saw this I couldn't figure out the unintended downside.
      • LEDs are efficient (if NYC can be retrofitted for less than $2million, there are literally billions to be saved in energy across the country.)
      • They can be switched on and off instantly (unlike sodium or mercury vapor lights) with little reduction in life (unlike incandescents) which should allow interesting usages. Why light an empty parking lot or path until motion detectors detect someone there?
      • Because of the
  • 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.
  • Sodium Vapor vs LED (Score:3, Interesting)

    by lobiusmoop ( 305328 ) on Saturday December 20, 2008 @02:21AM (#26182015) Homepage

    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.

    • LEDs aren't inherently blue light. Using proper LEDs or a proper mix of them, it shouldn't be that much of a task to duplicate that colour.

  • by B4RSK ( 626870 ) on Saturday December 20, 2008 @02:32AM (#26182051)

    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.

    • by Mashiki ( 184564 )

      We use LED signals here in Canada(and I'm sure in places in the US) in various places. My hometown uses them and I've seen them in Toronto as well. The problem doesn't come from the signals, the problem comes from large strings of lights down the road giving back a long range flicker as you drive by. While I can't say this will be an issue for a lot of people I'm sure there's a small minority that may have an adverse reaction to them.

      That being said, it may very well be less of a reaction to the current

  • 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?
  • by Jackie_Chan_Fan ( 730745 ) on Saturday December 20, 2008 @04:00AM (#26182379)

    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.

    • The idea itself isn't that bad, considering LEDs need a lot less energy (thus money) to operate. It depends on how it's going to be implemented. If they let city workers pile up overtime to swap ALL the lights at once, it's pretty idiotic.

      Phasing them out as they burn out anyway and have to be replaced, though, is a good idea.

      • Re: (Score:3, Insightful)

        by hab136 ( 30884 )

        Phasing them out as they burn out anyway and have to be replaced, though, is a good idea.

        Is it?

        Cost of running existing bulbs for the next 5 years: $10 million
        Cost of replacing with LEDs: $2 million
        Cost of running LEDs for the next 5 years: $2 million

        Numbers are pulled out of thin air, but I wanted to illustrate a point - it sometimes pays to replace something that is working.

        Presumably whomever is in charge of the replacement has done this math, and found it comes out ahead to go ahead and switch before

  • by serviscope_minor ( 664417 ) on Saturday December 20, 2008 @04:44AM (#26182517) Journal

    "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.

  • The problem with LEDs at the moment is that they give off an incredibly harsh, piercing light. Not sure if they're using phosphor coating or 3-colour LEDs to achieve the white light but the slightly blueish white they produce is pretty hard on the eyes.

    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 i

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