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Technology

NYC's 250,000 Street Lights To Be Replaced With LEDs By 2017 372

An anonymous reader writes "New York City Mayor Michael Bloomberg announced that the city's 250,000 street light fixtures, which currently use incandescent bulbs, will be replaced with LEDs by 2017. It's part of a plan to reduce the city government's emissions by 30%. The LEDs have a lifespan of 20 years, more than three times that of the current incandescent bulbs, and Bloomberg says it will save $6 million in energy and $8 million in maintenance every year. It will be the largest LED retrofit in the country. 'The first of three phases to replace the standard "cobra-head" high-pressure sodium street lights, which will upgrade 80,000 at a time across the five boroughs, is expected to be completed in December 2015 with the final phase expected to be completed by 2017. Following the replacement of roadway lighting, decorative fixtures in the city's business and commercial districts will be addressed.'"
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NYC's 250,000 Street Lights To Be Replaced With LEDs By 2017

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  • I wonder how many smaller cities have already done this?

    • by Animats ( 122034 )

      I wonder how many smaller cities have already done this?

      Redwood City, CA, near where I am, is doing it. It's striking, because Redwood City standardized on yellow sodium lamps some time in the 1930s. You know you're in Redwood City when the street lights turn yellow. The new daylight LEDs are a big improvement.

      If your community is doing this, push for solar power on some of the lights. Not necessarily all of them, but at least at street corners. That way, no matter what disaster happens, some lights will stay on.

      • I admire your "plan ahead" approach, but in 2 small cities I've seen where they had some that were solar powered, they ALL were damaged by the accompanying natural disasters so they really didn't help even when disaster strikes. :(

        They are just too fragile to hope to survive things like hurricanes, tornadoes, really bad thunderstorms, and earthquakes.

    • Stick with sodium (Score:5, Insightful)

      by mdsolar ( 1045926 ) on Friday October 25, 2013 @12:18PM (#45236775) Homepage Journal
      Near observatories to cut down on light pollution. LEDs are too broadband.
      • by fuzzyfuzzyfungus ( 1223518 ) on Friday October 25, 2013 @12:39PM (#45237119) Journal

        Near observatories to cut down on light pollution. LEDs are too broadband.

        On the plus side, if somebody is thinking about installing LEDs, that is (sometimes) a sign that light fixtures that have been, well, fixtures, for decades, sometimes quite a few of them, are getting their first re-evaluation in quite some time.

        It only helps if somebody pushes at the correct time; but if the fixtures are being reevaluated in anything resembling a serious way, that's your best chance to get action on things like fixtures that point upward, ill-designed fixtures that don't target their output very well, and all the various other dubious lighting decisions that help add up to light pollution.

        It's unlikely to be perfect; but LEDs (being costly; but easy to aim fairly tightly, as well as very good at doing accent work (say, lighting a set of stairs with small lamps set just above the steps, rather than one big bulb-on-a-stick pointed in the direction of the stairs and cranked to 11), do encourage more efficient targeting in a way that big, cheap, one-size-fits-all bulbs don't.

        • Yes, directing light to where it is needed is important as well.
        • It only helps if somebody pushes at the correct time; but if the fixtures are being reevaluated in anything resembling a serious way, that's your best chance to get action on things like fixtures that point upward, ill-designed fixtures that don't target their output very well, and all the various other dubious lighting decisions that help add up to light pollution.

          Unfortunately, the major impact around me is that our streets are now incredibly bright at night...they used the extra efficiency to make eve

      • From the few astronomers I've talked to, streetlamp design affects light pollution as much or more than what kind of bulb it's using. Many streetlamps, especially older ones, shine in every direction including up. Lights with a hood to reflect all of the light towards the ground are better for both energy consumption and light pollution.

      • Not a lot of astronomy going on in NYC.
        • Even small cities can affect light pollution from dozens of miles outside of the city. I grew up about 20 miles from a city of 60,000 and it gave off enough light pollution to effectively blot out much of the southern sky near the horizon. I imagine NYC's light pollution reaches much further.

    • Monterey, CA did it a little while back. One nice side effect I've noticed is less light pollution compared to the presidio which didn't change their lights. No idea about the cost savings though.
    • by fuzzyfuzzyfungus ( 1223518 ) on Friday October 25, 2013 @12:31PM (#45236979) Journal

      I wonder how many smaller cities have already done this?

      I think that it's not uncommon (though traffic signals usually go first, since LEDs have been cheap and good at red, green, and amber for longer than they've been either cheap or good for white, and bulbs-behind-filters have always had even more miserable efficiency than bulbs in general).

      LEDs are still pretty expensive, and white ones (because they are usually blue ones pumping a phosphor layer) are still less efficient than one might like; but one big advantage is lifespan.

      A replacement lightbulb doesn't cost much; but sending out guys in bucket trucks to deal with dead ones adds up.

  • Costs (Score:4, Insightful)

    by sfm ( 195458 ) on Friday October 25, 2013 @12:05PM (#45236581)

    Yes, there is a savings, but how much is it going to cost NY taxpayers up front ?
    Would a better strategy be to replace the sodium lights with LED style lights, as they wear out?

    • They're doing that *too* of course, since while they're rolling them out, they'll still need to replace broken ones in parts of town that they're not in.

      ...but the question is simply a matter of if it's more efficient to replace an existing, working, lightbulb with an LED.

      I know it was for me, but my replacement costs were low. [I didn't have to pay the laborer...]

    • by drnb ( 2434720 ) on Friday October 25, 2013 @12:13PM (#45236693)

      Yes, there is a savings, but how much is it going to cost NY taxpayers up front ? Would a better strategy be to replace the sodium lights with LED style lights, as they wear out?

      Yes, there is a savings, but how much is it going to cost NY taxpayers up front ?

      It looks like a 4 year program and the incandescents last about 7 years. So many of those bulbs will be due for replacement anyway.

      • by djlemma ( 1053860 ) on Friday October 25, 2013 @01:15PM (#45237733)
        They are replacing High Pressure Sodium lamps, which are not incandescent. The funny thing is, by the standard measure of efficiency used in the industry, the new street lamps probably will be LESS efficient than the old ones. HPS lamps can get above 100 lumens per watt pretty easily, and low pressure sodiums can even get up to 200 lumens per watt. They've been able to get efficiency like that in labs for LED's, but for production fixtures it's not very common.

        Of course, LED's often win out in real-world comparisons, because all the lumens are more efficiently directed where they need to go. Still, to get that much brightness, it's going to cost quite a lot of money.
    • Re:Costs (Score:5, Informative)

      by Anonymous Coward on Friday October 25, 2013 @12:20PM (#45236795)

      Nope, its actually cheaper to replace them in large blocks than to replace them one at a time. Old tech told me once that when they maintained the long tubes at the factory high up. Once a few went it was only a matter of about a year or two before the rest of the them did and it was more disruptive, time consuming, and costly to replace them one at a time than to do it all at once. So, I've followed this process for most of my larger lighting projects. If you are going to replace one brake light replace them all. If you are going to replace one headlight replace them both.

      Also, the nice thing about LED lighting is that the way it fails is it just doesn't produce as much light as it once did. So in 20 years if they want to put off the costs for another couple of years, it's entirely possible to do so.

    • Cities can and do borrow to pay for long term investments. If NYC issues bonds, then this is the sort of thing they support. The taxpayers see saving all along the way. If the bond rate is below inflation, they see even more.
  • 20 year lifespan (Score:4, Informative)

    by Bayoudegradeable ( 1003768 ) on Friday October 25, 2013 @12:12PM (#45236679)
    Let me first say that I live in New Orleans, so go ahead make all your inept government remarks now. That said, we did begin making changes in our traffic signals to LED lights and the big claim of "20 year lifespan" was made. Less than 5 years later I see many of the LED bulbs (really, clusters of bulbs, like a Lite Brite set) are now replaced with the traditional traffic signal bulbs. Not only did the LEDs not last very long, they aren't being replaced with LEDs but with the old style bulbs. Hope NYC gets LEDs from a better vendor than we did.
    • Because traffic lights go on and off and on and off all day long. They're a terrible idea for LED because the ballasts wear out doing that. The actual LED built into the thing is still perfectly OK actually. Your local government (and many others) have been scammed by clueless but well meaning greenies on the city council over the traffic light LED thing. Streetlights that come on and stay on all night long are a much better use.

      • by Kardos ( 1348077 )

        If that's true, then it's a terrible design. Only one of the lights is on at a time, right? So the ballast can run continuously, switching between red/green/yellow as appropriate.

      • Re:20 year lifespan (Score:4, Informative)

        by mspohr ( 589790 ) on Friday October 25, 2013 @12:50PM (#45237293)

        There is no ballast in an LED light.
        Fluorescent and sodium vapor lights have ballasts, not LEDs.
        All of the traffic lights in my area were switched to LEDs many years ago. I have never seen a single light that wasn't working properly.

      • Re:20 year lifespan (Score:5, Informative)

        by necro81 ( 917438 ) on Friday October 25, 2013 @12:51PM (#45237309) Journal

        Because traffic lights go on and off and on and off all day long. They're a terrible idea for LED because the ballasts wear out doing that

        LED lighting systems don't have ballasts. True, LEDs require power conditioning (for these applications, it's some sort of switched mode AC/DC converter with constant current output), but those kinds of circuits are highly efficient and robust. LEDs experience essentially zero degradation from being turned on and off repeatedly. All those blinky lights on the front panels of computers, all the flashing indicators on routers and switches, those are all LEDs.

        You are probably thinking of fluorescent lamps (tubes and CFLs), for which frequent on/off cycling is indeed a good way to make them die soon. No one makes fluorescent traffic lights precisely for this reason.

      • I think you've got this backwards.

        Incandescent bulbs don't thrive in constant-switching environments because there's an inrush of current when the filament is cold. That's why most incandescent bulb failures happen right when you turn the light on. It's less of a problem if you run the bulb below its design voltage, but that drastically reduces efficiency.

        LEDs have no corresponding issue. If you're very stupid about the way you build your power supply, that might fail (or even take out the LED), but I don't

    • Re: (Score:3, Interesting)

      by Megane ( 129182 )

      The problem with LEDs in traffic lights, in my experience just driving around, is that the main problem is the light module itself somehow fails such that some of the LEDs can't get electricity. This results in part of the LEDs not lighting. New Orleans is right on the ocean, so the salt water in the air is more likely to cause corrosion problems. The equivalent would be blaming incandescent lights because the bases of the lamps fell apart after wind shook the signals around too much.

      And then there is the

    • I recall a suburb of Los Angeles that installed some LEDs in traffic signals in the late 1980s. The was a visibility problem based on angle. At one light, maybe more but I only witnessed this once, when within about 10 feet of the limit line you could not see which light was illuminated. So the first car stopped at the light could not tell when it turned green.
    • by Bratch ( 664572 )
      Traffic signals are a different application. A few yeard ago I heard of a city somewhere up north that replaced all their incandescent traffic signals with LEDs. When winter came, the new signals, using 90% less power, didn't emit enough heat to melt the snow that accumulated in the signal housing. The snow can build up enough to completely block the light, resulting in confusion and accidents all over the city. They had to either go back to incandescents, install a heater element, or modify the housing
    • by ebno-10db ( 1459097 ) on Friday October 25, 2013 @12:38PM (#45237097)

      Nobody said they worked underwater.

    • Yeah, exactly. Someone somewhere has won a huge contract based on probably unverifiable claims of LED lifespans.

    • This is precisely correct. LEDs, when properly designed and manufactured, have lifespans that are just phenomenal. I have all LEDs in my house. The ones that I bought that were high grade CREE LEDs I expect to have the rest of my life. Zero failures after 5 years of use so far.

      On the other hand, some of the cheaper ones I've bought have often not lasted 2 years. I tried some cheaper ones just to see how well the worked. They often didn't even produce the amount of light they were claiming.

      In conclusio

  • Does it take to change a light bulb?
  • One of the side benefits of traditional bulbs is that the heat generated helps keep them clear of snow and ice. I don't think LED's generate enough. Anyone know how they are handling that?

    • by necro81 ( 917438 )
      How often does the underside of a street lamp - ya know, the part that the light comes out from - get covered with snow?
  • Like 'dim' streetlights in Winter because they have frozen over, and (for cities that don't think of these things ahead of time) failure to install seasonally enabled heating units into the enclosure. All in all the human-time and effort of manufacturing and deploying these new solutions, along with the added heater circuit to make them useable, will really eat into that eco-energy difference equation.

    Lots of eco initiatives these days come down to someone smiling and pointing to a little device that saves

  • Sodium light is a kind of light that the eye is very responsive to, and it is perfect for illuminating roads and freeways: any one of you that has done some nocturnal driving will agree that the difference between driving with your vehicle's headlights only on an otherwise pitch black road, with driving under sodium lights is huge.

    Other technologies that produce bright light (Xenon, Halogen, all those 'energy saving' graded ones etc) are IMO are to bright to be of such use. Notice this: they are very bright

  • by An dochasac ( 591582 ) on Friday October 25, 2013 @01:21PM (#45237823)

    Incandescent? Are we stuck in a time warp? What city has had the money to waste on incandescent streetlights since the 1960s? LEDs are less efficient than the orange sodium streetlights but probably more efficient than the more common high pressure sodium. They have some key advantages. The first is that they can be physically much smaller than high voltage discharge lights which means it takes smaller optics to throw the light where you need it. But where light trespass remains, LEDs present an interesting option. I how many of us end up having to put ugly black-out shades in front of bedroom windows to keep unwanted streetlight glare from keeping us awake? What if an LCD shutter were synchronized to close exactly when street light LEDs were on and open when they're off. Suddenly you see the natural night sky from your bedroom window, are awakened by natural morning sunlight.

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