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United States Businesses The Almighty Buck The Courts Technology

Detroit's LED Streetlights Are Going Dark After a Few Years (detroitnews.com) 271

Detroit's Public Lighting Authority has filed a federal lawsuit Monday against the manufacturer of nearly a third of the city's 65,000 streetlights, after it found that upward of 20,000 LED lights are "prematurely dimming and burning out" and putting the city's revitalization progress "in jeopardy." The city estimates a fix would cost millions. Detroit News reports: The issue was discovered last fall during routine surveys of the lighting system, and it's tied to defective units that were either "charred, burned, or cracked," according to a February letter from the lighting authority's law firm. The California-based manufacturer (Leotek Electronics USA) acknowledged in a December letter to the lighting authority that it had experienced "a higher number of reports of failures" in models dimming city streets, primarily in west side neighborhoods and a number of Detroit's major thoroughfares.

In the Dec. 17 letter, Leotek administrator Hy Nguyen said the company had determined "the problem is excessive heat that can burn the lens directly above the LED." "We apologize for the problem you have experienced and will work with you to correct the problems," Nguyen wrote. But in recent weeks, Leotek officials have gone silent, according to the lighting authority. A representative for Leotek did not respond Monday to requests for comment. The lighting project has been held up by Mayor Mike Duggan and others as an early success in the city's effort to restore basic services. Before the three-year, $185 million overhaul, about 40% of Detroit's 88,000 streetlights didn't work. The LED lights provided by Leotek were anticipated to last for at least a decade.

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Detroit's LED Streetlights Are Going Dark After a Few Years

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  • Quality (Score:5, Interesting)

    by markdavis ( 642305 ) on Tuesday May 07, 2019 @08:45PM (#58554980)

    And this has been an issue. Interestingly, my very first LED bulb, a positively ancient Phillips, has been working fine for so many years, I forgot how old it is (10 years, I think?). And the ones I bought a few years after- dimmable tracklight floods- still running strong. But the ones I bought last 5 years, of various brands, for a quarter of the price- half of them are dead or dying.

    It is Deja-Vu. Went through that with the CFL's too- the early ones lasted for a decade or more, the later ones died quickly, no matter the brand.

    So do keep this in mind when computing just how much "savings" you will get. I am still a HUGE LED fan, but it is hard to be optimistic when it seems impossible to find consistent quality ones anymore.... it is an annoying gamble.

    • Out of five original Cree lights I've bought, the glue holding on the glass globe has failed on three of them. The cheapest, crappiest color-changing lamps I've bought all still work.

    • I take a relative view of these bulbs. It says it lasts 15 years on the package. Even if it only lasts 1/3 of that, I'm still getting a bulb that lasts longer and is cheaper to run than an incandescent.

      • by caseih ( 160668 )

        Will it last for 5 years though? I have my doubts. I've experienced a pretty high failure rate with my LED bulbs in the last couple of years. It's quite discouraging. The most common failure mode for my bulbs is they start blinking off, and eventually fail completely. When I take them apart, I often find burn marks on the board beneath the LED units. Most likely from the heat from the driver circuitry underneath. In many cases the individual LEDs still work, but the rectifier is burned out.

        But traditio

      • I just replaced an old incandescent in my house. I didn't even know it was there. It's in the fixture above the staiway, so it's on often enough. Probably been in there since I moved into the house a decade ago. incandescent bulbs seem to last plenty long in my opinion. I don't think I have any more in the house. The LEDs and CFLs never got the life they claimed on the packaging. But they often have sales or government rebates on LED bulbs for $1 a piece, so I just pick up a few extra whenever I see the dea

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      In my experience it's not a quality problem, it's a design problem. They are engineered with zero margin and pushed past the maximum ratings of all components to squeeze every bit of brightness out of the cheapest possible circuitry. I've seen this on many many dead LED light bulbs. It would be a simple matter of decreasing the current by 10 or 15% and the thing would probably last forever. Now, do you think manufacturers want them to last forever? Or would they prefer if they burn out after 1-2 years

      • Same thing happend to my LED backlit TV. The whole picture when completely dark although you could see the image if you shine a flashlight on it. Did some searching online to see how to fix the problem, and it seems to come up quite often. Ordered a whole set of LED strips (correct ones for the TV, not generic LED strips) from China for $50 and managed to fix my TV. Plus I have extra parts for when the next one dies. Apparrently it's a well known issue with certain TVs. they drive up the brighness to make

    • by jimbo ( 1370 )

      Well yes, choose wisely. I bought some Xpeoo LEDs that failed within a year. Replaced with Philips that have lasted for three years so far and still going.

    • My data point: When I bought my house, I bought 48 Cree bulbs (60W incandescent replacements) on closeout at Home Depot (about $1.97 each if I recall, marked down from $7/ea). Installed 40 of them. 4 of them failed within a few weeks. I returned those for a refund (HD didn't have stock to exchange them since they were closeout specials). I replaced the failed ones with new ones out of the 8 remaining. They have all been working without problems for 4 years now. The last 4 are still in a box in my close
    • by Kokuyo ( 549451 )

      I've had problems with all cheap and medium priced LEDs.

      I've also had issues with the very pricey Osram brand.

      Philips are holding up so far.

      What I noticed is it's not the LEDs that die. The current batch that is dying is of the corn cob variety and the flicker on and off but always all of them and often to full brightness. I believe very much that this is badly handled planned obsolescence and the eletronics are just crap. I bet if I opened one and provided a good power source they'd light up like a sunrise

    • by havana9 ( 101033 )
      I have some old style ballast fluorescent light and while they have they problems, they flicker and buzz, is the tube that fails and start to flash when turned and then the after some time the arc fails to start. Newer electronic fixture from a reputable source are working better the tube doesn't fail in a flashing fashion but instead get dimmer and dimmer. I have some cheap fixtures bought as store brand and internally containing some no-name circuit. I have all of them failed before the tube, stopping s
    • by AmiMoJo ( 196126 )

      The EU is looking at improving standards for testing LED bulbs to try to come up with better MTBF numbers, and to track dimming. The obvious thing to do is use the lowest MTBF of all the components, but that usually ignores the operating conditions, primarily heat. Or more specifically heat cycling.

      10 years at 85C is likely to be optimistic for a bulb that goes through one or more heating and cooling cycles per day.

  • No Shit (Score:5, Interesting)

    by Anonymous Coward on Tuesday May 07, 2019 @08:57PM (#58555038)

    Anyone with basic electronics experience could have told you this would have been the result of moving to LED street lighting. Lets put a light source that requires a sophisticated LED driver with electrolytic caps into an enclosure that sits in the sun for 10-12 hours of the day and probably bakes at well over 120F for a part of that day.

    LED lighting was the dumbest move in street lighting. It is not a significant electrical savings over the use of HPS. HPS bulbs last well over half a decade with the simple magnetic ballasts in them lasting the life of the fixture (decades). The environmental issues of the small amount of mercury in the bulbs was insignificant. Since it is power companies or city workers that maintain these lights it is easy to collect the bulbs for proper processing or recycling.

    I already see the same problem described in this article with LED street lighting that has been deployed in my area as well. Sure the LEDs if driven properly have a lifetime significantly longer than HPS, but the driver circuits do not. Add on top all these things are made for the cheapest cost in China and you have street lights that fail 2-3 years into their life.

    • "baking' in 120 F container doesn't seem like much, especially when the light shouldn't be running in those circumstances, except in some sort of standyby/photocell mode waiting for night to fall. Automotive OEMs test for over 170 F degree external surface temps due to hot area/dessert sun loading, and internal temps can run higher. led interior lighting, tail lights and other lighting still survive the expected 10+ year life cycle. Even if the enclosure bakes at 150 F on a hot day in Detroit, the lighti

  • Long live HPS... or better still LPS...

    I hate LED street lights or at least the blinding lowest bidder shit they are putting up around here.

  • Lumen per watt (Score:2, Informative)

    by e3m4n ( 947977 )

    High Pressure Sodium and Metal Halide HID lighting still has higher lumen per watt than LED. Ask any indoor pot farmer. LED requires less heat removal but then again they are more heat sensitive even though they give off less heat. HPS and MH are much hotter to the touch, but despite that they _still_ produce more lumen per watt.

    HPS 1000w bulb gives off 150,000 lumen 150 lumen/watt
    MH 1000w bulb gives off 100,000 lumen 100 lumen/watt
    LED 30-90 lumen/watt

    I have seen some LED claiming better efficiencies but w

    • Even so, LED streetlamps can get very HOT! Not as hot as the equivalent incandescent, but these aren't like your home bulbs and instead they're meant to be very bright and light up the street below them. We have some of these streetlights in our lab and I can see how they might lose reliability if the manufacturer doesn't manage the heat problem well.

    • High Pressure Sodium and Metal Halide HID lighting still has higher lumen per watt than LED. Ask any indoor pot farmer. LED requires less heat removal

      You realize those two statements are contradictory? If a bulb has higher lumen per watt, that means a smaller percentage of the wattage becomes waste heat. Meaning it runs cooler for a given amount of light.

      • by e3m4n ( 947977 )

        That would be the theory. However this is been observed and measured by many many people. I have seen how much heat a 1000 W grow light puts out. It’s damn hot. The fixtures are enclosed with 6in duct outlets on either side to push the air out of the grow room. Even the hood is very warm to the touch. That sort of ventilation is not needed with LED. Yet the math doesnt lie. Lm/w the HPS outperforms. Perhaps LED suffer some other form of inefficiency not manifested as heat whereas HPS is a purely r

        • by jabuzz ( 182671 )

          All waste must become heat, otherwise it's not wasted. This is thermodynamics 101. What you are claiming is that some of the most fundamental laws of physics are wrong. I suggest you write a paper because if you are correct (which you are not) then there is a Nobel prize in it.

          • by e3m4n ( 947977 )

            That is completely untrue. That is only true in purely resistive loads. Thats the point of a power factor. In thermodynamics heat is typically not considered ‘waste’. Its considered usable energy. Do you know what the term Latent Heat of Vaporization is? There is no measurable difference in temperature for water at 100C and pure steam. The energy required to go from liquid to gas cannot be measured with a thermometer. This is partly why nucleic boiling has better heat transfer properties than p

    • by Kokuyo ( 549451 )

      I find the LED streetlights in switzerland provide better contrast while not creating too much "glare". It looks much softer in a way. I very much appreciate that aspect.

  • by dohzer ( 867770 )

    Did they remember to use the dimmable bulbs if the circuit has a dimmer switch installed?

  • Observation (Score:5, Informative)

    by ElizabethGreene ( 1185405 ) on Tuesday May 07, 2019 @10:43PM (#58555342)

    There is a subtle "feature" in how most LED bulbs are designed. A single LED has a fantastic mean time between failure (MTBF). In LED lightbulbs the COB chips have large numbers of these LEDs wired in series That means that a single failure takes out the entire unit. The MTBF of a bulb is dramatically lower than the MTBF you'd expect from a single LED.

    Combine this with race-to-the-bottom cost management on power supplies and thermal management and you get bulbs that are surprisingly short lived.

    I still buy them though. I prefer blue light to yellow, and I despise the slow start of CFLs.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      In street lamp luminaires LEDs are usually wired in parallel.

      What a lot of papers like Gauging the Lifetime of an LED [digitallumens.si] would have you believe is that LEDs typically have much greater Lumen Maintenance Standard lifetimes than incandescent globes of 36-60,000 hours (where the LED degrades to 50% of its rated brightness), and that MTBFs can be ignored because they're much greater than that. What they fail to disclose is that these figures are arrived at for single 5W LEDs on high quality boards and heat sinks.

  • In Ontario and much of of the North East we use street lighting at night, when almost all our electrical generation is from hydro, nuclear and wind. We don't have the brightest voters in this city. There's a reason we complain about American pollution and climate change denial while per capita we are significantly worse, the reason is poor critical thinking skills.
    • It's not poor critical thinking skills. It is the same problem as it has always been. Tribalism. Every issue gets boiled down into Group A vs Group B and the moment you espouse a view that is contrary to one group you get labeled into the other group so if you do not pick a side and believe in it like a religion you get screwed.

      Yes, there are dissenters on all the sides, but that is the reason for the group... to keep them covered by the rest of the sheep that would only attack them if they get too noisy

    • Are you advocating that the street lights only be turned on during the day ?
  • by FeelGood314 ( 2516288 ) on Tuesday May 07, 2019 @11:03PM (#58555402)
    They under bid, sold a crappy product and didn't have the margins to cover the cost of all the recalls. The labour costs for the replacements will exceed the cost of the bulbs by over 50%. Leotek has no possible way of upholding their warranty.

    This sucks for everyone. The people of Detroit but also any small company that is trying to win a large contract with a government agency. I've worked at many small companies that had amazing products. We would win all the initial pilot programs, spend a fortune on support for the pilots but at the end of the day no state or city government is going to buy 100 million dollars from a small company that has less than 2 million in assets. Our big multinational competitors could actually make a product that in one case would catch fire in peoples homes and we would still lose the bids.
    • by AmiMoJo ( 196126 )

      They should have required Leotek to get insurance. The insurance company would want to see the bulbs properly tested and realistic lifespans given. And if it still went bad they would be paying out now.

  • Seems that Detroit's contracts department is incompetent. They shouldn't have to pay a dime to replace faulty equipment.
    • I think the problem is more that honoring the warranty will bankrupt the supplier, so the company is stalling while selling the office furniture and updating their LinkedIn profiles.
  • They agreed to replace the defective lighting in Berkeley Back in February, but they seemed to have clammed up on Detroit. I think they sense they are in deep doo-doo. Perhaps they are skimping on material or manufacturing QA to milk these contracts for what they are worth. Replacing the defective fixtures will cost the company tens, if not hundreds of thousands of dollars.

    https://www.dailycal.org/2019/... [dailycal.org]

  • Are the LED street lamps the ones that have a failure mode whereby they flash intensely brightly every few seconds ? There was one in Denver that I drove by often that did that and it was extremely distracting / hard on the eyes.
  • Whenever I cross the pretty much brand new (2011) bridge across Lake Champlain from Crown Point, NY to Chimney Point, VT, sections of it's LED lighting are out of service. Not a big deal. Cars have headlights, and foot traffic at night in the middle of nowhere with subfreezing temperatures much of the year is, as you might imagine, minimal.

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