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Power Transportation

Midwest Seeing Red Over 'Green' Traffic Lights 839

theodp writes "Many municipalities have switched to LED traffic signals because they burn brighter, last longer and use 90% less energy than incandescent bulbs. But they also emit less heat, meaning they sometimes have trouble melting snow, causing problems across the Midwest. In Wisconsin, snow blanketed LED traffic lights in some towns, leading to crashes at intersections where drivers weren't sure whether to stop or go. The unintended consequences of the green technology were also identified as a 'contributing factor' in the death of an Illinois woman hit by a driver who blamed the snow-covered energy-efficient signal for giving the appearance of a normal green light instead of a left-turn signal. 'We can remove the snow with heat, but the cost of doing that in terms of energy use has not brought any enthusiasm from cities and states that buy these signals,' said the CEO of an LED traffic-signal manufacturer. 'They'd like to be able to take away this issue, but they don't want to spend the money and lose the savings.' In the meantime, some towns are addressing sporadic problems by dispatching crews to remove snow or ice from signals using poles, brooms, and heating devices." We were discussing these recently at the office — several folks in the building are red/green color blind and different street lights are differently distinguishable.
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Midwest Seeing Red Over 'Green' Traffic Lights

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  • by Anonymous Coward on Wednesday December 30, 2009 @09:58AM (#30593428)

    Oh that's right... we do! If you get to an intersection and the light isn't working or isn't visible, you treat it like a four-way stop.

    • by nschubach ( 922175 ) on Wednesday December 30, 2009 @10:03AM (#30593528) Journal

      I thought of this, but in the snow cover situation, only one side thinks it's a four way stop. You'd have to have a "snow sensor" and shut down all 4 sides of the light for that to work.

      • by i.r.id10t ( 595143 ) on Wednesday December 30, 2009 @10:23AM (#30593856)

        Or have a snow-sensor and kick on a small heating device...

        Sure, you are using more N-R-G by creating the heat to do it with so the technology is less green, but even this southern non-snow savvy guy realizes that using *some* N-R-G during a few months of the year to de-ice/melt/whatever is better than creating waste heat with inefficient lighting 24/7/365

        Besides, what is the "green" cost of a car accident where oil, gas, battery acid, etc. may be spilled, as well as emergency vehicles cranking up and running to the scene, etc?

        • Re: (Score:3, Insightful)

          Heck, even a manually switched heat function would be sufficient. A cop or city employee could turn it on whenever the light seems like it's blocked.

        • by RobertM1968 ( 951074 ) on Wednesday December 30, 2009 @11:08AM (#30594684) Homepage Journal

          Or have a snow-sensor and kick on a small heating device...

          Sure, you are using more N-R-G by creating the heat to do it with so the technology is less green, but even this southern non-snow savvy guy realizes that using *some* N-R-G during a few months of the year to de-ice/melt/whatever is better than creating waste heat with inefficient lighting 24/7/365

          Besides, what is the "green" cost of a car accident where oil, gas, battery acid, etc. may be spilled, as well as emergency vehicles cranking up and running to the scene, etc?

          That's the best suggestion. And it's trivial, extremely cheap technology. Outdoor surveillance cameras have used it for years - some even with dehumidifier devices as well.

          And the beauty is, even when the heater is on, it will still use less energy than the incandescent light, since it only needs to heat the lenses to a certain level over freezing temperature. So, I'd expect, even with the heaters on, there should be a decent savings in electric costs.

    • by Carewolf ( 581105 ) on Wednesday December 30, 2009 @10:04AM (#30593546) Homepage

      What do you do if only part of the lights were covered, especially if the parts covered are extensions such as no left-turn? I know it is much to ask, but as minimum, maybe you should Read The Fucking Summary.

    • The law is far too lax when it comes to issuing driver's licenses. I'll never forget years ago, when I went to take the written test I nervously asked the examiner "how many questions am I allowed to miss?". The answer was 12 ! That's 12 out of 78. No wonder people get confused as soon as the expected routine changes in even the smallest way.
      • Re: (Score:3, Interesting)

        by Microsift ( 223381 )

        I agree, I haven't taken a written driving test in over 15 years. When I did take the test, one of the questions was (paraphrasing) "How often do you have to get your license replaced." What a ridiculous question (give me my license and I'll read the answer off of the front). I wonder what real question got crowded out by this irrelevant question (If it's not obvious, I missed the question).

      • Re: (Score:3, Interesting)

        by TheCarp ( 96830 )

        I half agree.

        I think I favor less enforcement, and less laws overall. Most of the driving rules, in terms of real safety, are overly cautious
        "Best Practice" guidelines at best. Speed limits are just ridiculous, in general. People are going to drive the speed they feel safe, regardless of what the stupid sign says. That speed is usually 10-15 MPH higher than the sign. Yearly safety inspections? I can see emissions checks every few years, or a safety check after 5 or so. However, regular safety inspection rea

        • Re: (Score:3, Insightful)

          by Qzukk ( 229616 )

          Most of the driving rules, in terms of real safety, are overly cautious. "Best Practice" guidelines at best

          The driving rules are designed to protect drivers who obey the rules from other drivers who are obeying the rules, thus we're commanded on what side of the road to drive on, who goes first at a stop sign, what lanes you're allowed to turn from, when we're allowed to pass slow drivers, and so on.

          The problem is that nothing but attentiveness and reaction time will protect people from drivers who are not

          • Re: (Score:3, Insightful)

            by TheCarp ( 96830 )

            Up to a point sure. However, you don't have to obey all of the rules 100%, or even CLOSE to it, to drive safely with other drivers who are obeying the rules, or attentitively breaking them like you are (which is what the vast majority of drivers do, NOBODY obeys ALL of the rules 100%)

            I don't think we need more rules, most of them could be relaxed, and relaxed a lot. The only evidence that I need is that, as I said, the majority of drivers relax the rules and drive as such already. I do not believe that it m

            • by Anonymous Coward on Wednesday December 30, 2009 @02:02PM (#30597776)

              I don't think we need more rules, most of them could be relaxed, and relaxed a lot. The only evidence that I need is that, as I said, the majority of drivers relax the rules and drive as such already. I do not believe that it makes sense to set the bar for proper driving above what the average person is actually going to do on the road.

              ~40K dead Americans per year say you are wrong.

              The real problem is NOT the people breaking the rules on purpose. They generally are paying attention, know the rules, and are ready to make adjustments. The problem is the people who either don't know the rules in the first place, or aren't paying attention. There is a HUGE difference between rolling through a stop sign at an empty intersection with unobstructed visibility, and rolling through without even looking because you were playing with your radio.

              After 20 years of studying drivers and how accidents happen, I can tell you that you are wrong about them paying attention.
              90+% of drivers are operating on autopilot. They are not paying attention and are just letting the autopilot handle everything. This is one reason that they take driving for granted and feel just fine texting or talking on a cell phone while running other drivers off the road. Most crashes happen when 2 inattentive drivers hit each other. If you have an inattentive drive and someone who is actually driving the driver avoids the person who is oblivious to the situation.

              Who cares if I only bring my car down to second gear at stop signs? I am ready to stop. If there's another car who has right of way, I stop. If there's no other cars, I am slow enough to stop if I need to because someone else is blowing through, so no safety hazard is caused. If i have enough visibility to roll through at the speed that I am rolling through, and the situation isn't a dangerous one, then... how exactly does the rule make sense?

              I care and so does anyone who avoids you hitting them because your "only dropping to 2nd gear for stop lights" becomes part of your autopilot and often you may not actually notice another car has already stopped at the intersection and is now proceeding to use their right of way when you blow the red/stop sign.
              I have seen drivers (I hate to use this term for commuters who have somehow ended up behind the wheel and have no interest in teh art of driving) use this same argument and then drive and fail to notice other cars at intersections as they blow lights/signs. They still say that everything was clear and that there was no other traffic due to autopilot.

              The advantage of your post is that it clarifies what the person who got killed did wrong. They went through an intersection while assuming other traffic would behave in a given way without even observing the traffic to see if this was likely. I really don't care if you have a green if it looks like an SUV coming up to a red and who will T bone you, is not slowing, don't just say "I have the right of way!" and head to your death. You will be in the right and just as dead as if you were not in the right.

              If people cared about highway deaths we'd see a few things.
              1. The news would report how many people died in the roads of their state the previous day and across the US.
              2. Laws would begin to target bad drivers and not boogiemen like speeders and drunk drivers.

              #2 sounds unbelievable so I should explain. When you are just as impaired using a cell phone as you are at the legal BAC level for DWI and only one of these has heavy legal ramifications... yeah, a boogieman has been created. Also if you research the criteria for a drunk driving crash you may be amazed at how a crash with no alcohol can still be classed as a drunk driving crash.
              The police say that speed is the #1 cause of crashes. This is wrong. putting things where they do not belong is the #1 cause. If we wanted to reduce raod deaths the police would crack down on people rolling reds and stop signs, people commuting in the wrong lane, improper signal use, and other things which indicate bad drivers. Get the inattentive dummies off the road and watch the death rate plummet.

    • by Hognoxious ( 631665 ) on Wednesday December 30, 2009 @10:11AM (#30593644) Homepage Journal

      If you get to an intersection and the light isn't working or isn't visible, you treat it like a four-way stop.

      He did - he went straight through just like anyone driving a Dodge RAM does.

    • The problem is, this doesn't just cover the light,it apparently also can make a signal appear to be something it is not.

      This is a severe problem. If they were simply obscured, you are right, fairly easy to deal with. But if they appear to not be obscured, but the snow causes misinterpretation as apparently has happened, bad things will happen that are not the fault of the drivers, but the idiots who installed these systems without the manufacturers option for a heating element.

    • One of my many angers when it comes to others and their lack of knowledge about traffic laws is this.

      Luckily, where I live now they seem to understand the four-way stop law. However, in Indianapolis if a traffic light goes out everyone seems to think that the "larger road" has the right of way. Try to follow the law and you get flipped off almost instantly.

      One of the most basic emergency rules and no one there can seem to remember it.

    • by guruevi ( 827432 )

      I really hate the 4-way stop in the USA. In Europe there is no such thing as a 4-way stop, you have 2 stop signs in one direction and 2 yield signs in the other direction.

      If 4 cars (or 2 or 3 for that matter) come to the intersection at the same time, who goes first? Unless you have a very precise clock you can't really figure out who goes first. The rules get really complicated at that point, you have to give priority to the right (2 cars), you have to give priority to the direction with the most cars (3 c

    • by Cerebus ( 10185 )

      ...and the light on top (vertical hang) or to the left (horizontal hang) is *red*. That's actually law too, IIRC.

  • by alen ( 225700 ) on Wednesday December 30, 2009 @10:00AM (#30593466)

    idiot driver should be prosecuted since everyone knows the third light from the top is regular green and not a turn signal. i've seen intersections with broken lights before and people are very careful when they go and make sure the other guy is going to yield.

    some people are always in a constant state of hurry and can't seem to wait a few seconds

    • Re: (Score:2, Insightful)

      by CrazyDuke ( 529195 )

      It's not always that they are in a hurry. It's often just a plain old sense of entitlement.

      • It's not always that they are in a hurry. It's often just a plain old sense of entitlement.

        It's not always that they are in a hurry. It's often just a plain old sense of selfish, anti-social arrogance.

    • Umm... you must have some screwed-up traffic lights where you are, relative to around here. The turn signals replace the third light in my area, not supplement.
    • Re: (Score:3, Interesting)

      by SeaFox ( 739806 )

      idiot driver should be prosecuted since everyone knows the third light from the top is regular green and not a turn signal.

      Are LED fixtures made to follow these same rules? On an LED light, the same light can easily be used to display both by simply not turning on all the LEDs.

    • Re: (Score:3, Informative)

      by Brett Buck ( 811747 )

      idiot driver should be prosecuted since everyone knows the third light from the top is regular green and not a turn signal.

            Bullshit! I would wager at least 25% of the LED lights I have seen have the third light as a combined left turn or straight green. LEDs permit that easily - just turn on the elements for the left turn, then all of them, when it goes from "left" to "green".

             

  • Good Advice (Score:5, Insightful)

    by Frigga's Ring ( 1044024 ) on Wednesday December 30, 2009 @10:00AM (#30593470)

    In Wisconsin, snow blanketed LED traffic lights in some towns, leading to crashes at intersections where drivers weren't sure whether to stop or go

    If you're not sure to stop or go, the answer is "stop". I can understand if it's dark and you don't see the traffic lights because they're covered with snow, but if the lights at the intersection aren't working, that doesn't mean the light is green. It means stop and go when it's safe to.

  • duh (Score:2, Insightful)

    by Anonymous Coward

    why don't they just angle the lenses downwards with less of a hood? problem solved.

    • Re:duh (Score:4, Insightful)

      by Abstrackt ( 609015 ) on Wednesday December 30, 2009 @10:56AM (#30594492)

      why don't they just angle the lenses downwards with less of a hood? problem solved.

      I'm going out on a limb here, but you probably don't live somewhere that gets a lot of snow. Don't get me wrong, I think your idea would work in a lot of scenarios but not all of them. Where I live, we get the odd blizzard that puts a thick layer of ice and snow on everything. The wind pushes sticky snow at seemingly impossible angles preventing you from making out any lights or signs.

  • Simple (Score:2, Interesting)

    by Thelasko ( 1196535 )
    Put a small heater in the traffic signal that turns on below 0C (32F). Problem solved.
    • Re:Simple (Score:4, Informative)

      by qoncept ( 599709 ) on Wednesday December 30, 2009 @10:07AM (#30593596) Homepage
      Genius. I would say RTFA, but you all you really need to do is read the summary.
    • Put a small heater in the traffic signal that turns on below 0C (32F).

      Or better yet, wire the heater to one of these [amazon.com] and have someone drive around and turn them on when it snows.

      Either way, if the municipalities don't solve the problem, they will get sued. How much does that cost?

    • Sure, problem solved, but the summary points out why that's not happening:

      We can remove the snow with heat, but the cost of doing that in terms of energy use has not brought any enthusiasm from cities and states that buy these signals,' said the CEO of an LED traffic-signal manufacturer.

      • Re: (Score:3, Insightful)

        by zippthorne ( 748122 )

        So, against a whole year of savings, they can't accept five or six days of artificial heating? It has to be all or nothing?

        What are the addresses of these math deficient city managers, so that local engineers can visit them and slap them in the face with an intro thermodynamics book.

    • Of course, they could always put a sloping cover above the signs so it doesn't get, well, covered in snow.

  • New design needed? (Score:4, Insightful)

    by nschubach ( 922175 ) on Wednesday December 30, 2009 @10:02AM (#30593512) Journal

    Maybe the lights need to take on a new form? What kind of problems would arise from coating each LED's sides with black paint (to replicate the duty of the indirect sun shades) and spacing the LEDs out so snow can pass through them? Or possibly shaping the LED or a cover as a cone shape so that it's harder to cover with snow?

    • Then this would confuse people, because, you know, they're so used to the round traffic light design.
      • if you look at a cone straight on, it's still a circle. There are also several square LED traffic lights that's I've seen around.

  • Propaganda? (Score:5, Interesting)

    by CrazyDuke ( 529195 ) on Wednesday December 30, 2009 @10:10AM (#30593626)

    I read this and I almost immediately thought "propaganda." Why? A appeal to fear based on a insignificant and easily fixable event, then attempting to tie the fear to larger political concepts. Fear change! Fear green! Equals death! Keep same! Same is warm! Same is reliable! Same is safe! You don't have to think about same!

  • by Junior J. Junior III ( 192702 ) on Wednesday December 30, 2009 @10:12AM (#30593652) Homepage

    Red/Green colorblindness is nothing new; that's why the lights are standardized to have green at the bottom and red at the top. If you can't distinguish red from green, you can at least distinguish top from bottom. Why is that not a perfectly acceptable solution?

  • They say the problem is easily remedied by maintenance crews using brooms and occurs so infrequently -- once or twice a winter -- that it does not outweigh the benefits of energy efficiency.

    Tell that to the surviving members of Lisa Richter's family.

  • Hmm... (Score:4, Interesting)

    by neowolf ( 173735 ) on Wednesday December 30, 2009 @10:15AM (#30593704)
    I wonder if there is some other design factor that is causing this problem, beyond just the LED lights not putting out as much heat as incandescent ones. I live in Colorado and most of the traffic lights here (Denver area) now use LEDs. I don't believe I have ever encountered one that was clogged with snow or ice. Not to say it doesn't happen, but I wonder if the traffic lights here are simply designed differently (better covers/shielding, spacing, ?).

    It seems like a simple solution would be a small heater incorporated into the LED lamp assembly that only turns on below a certain temperature. Better yet- perhaps a sensor could be used to detect if the lamp was covered, perhaps by reflectivity. This would probably still use a lot less electricity over the course of a year.
    • Re:Hmm... (Score:5, Informative)

      by CoreDump ( 1715 ) on Wednesday December 30, 2009 @10:25AM (#30593908) Homepage Journal

      The ones you see around Denver *are* designed differently.

      The shield around the lights is open on the top, so that it funnels wind downwards and blows the snow off of the light. The ones in Illinois are not. The Colorado shields cost ~$30.

      This isn't a case of LEDs being bad. Nor is it "greens run amuck". It's idiots run amuck.

      The driver of the truck should be prosecuted. In every light cluster with turn arrows, the turn arrows are on the bottom. They are NOT the solid green. And being from Illinois, in Driver's Ed we were all taught that Green does not mean 'Go'. It means *proceed when the intersection is clear*. So, failure on several points by the driver of the truck.

      Illinois needs to install the same snow shields that Colorado and other states have successfully done with their LED light installations.

      We'd probably have them already, except we spent all our DOT money on 'Rod R. Blagojevich - Governor' signs.

  • by bigtrike ( 904535 ) on Wednesday December 30, 2009 @10:15AM (#30593708)

    Why would the heaters have to use much energy? It sounds like they're not needed very often. You could automatically trigger them via external light/temperature sensors with some minimal processing or modify the red light camera software to trigger them. The only real downside is massively increasing the complexity of what is currently a very simple device.

    A simpler answer might be to train people that they actually need to slow down if a traffic signal is not fully visible.

  • ...and not because they are green. Having to heat them to melt the snow will mean less savings, which may well mean they switch them back to incandescents. Not exactly rocket science. Ironic, but mostly simple economics.

  • We were discussing these recently at the office — several folks in the building are red/green color blind and different street lights are differently distinguishable.

    I had trouble parsing that sentence. Is the statement that the colorblind can tell the difference between LED's and bulbs? Because the non-colorblind can also.

    Is the statement that the colorblind can tell the difference between the red and green lights? Because that's why they have a standard. The red one is always in one of two places. The green one is always opposite that one. Really, if they changed the lights to a pure white, they would still work for the non-colorblind.

    So yeah, 'say what?'

  • by paiute ( 550198 ) on Wednesday December 30, 2009 @10:20AM (#30593812)

    My town mistakenly ordered IED lights. These remove their own snow.

    • Re: (Score:3, Funny)

      by Kozz ( 7764 )

      "We used to dream of having IED lights!"

      My town ordered IUD lights, and I can tell you there was much argument about their installation.

  • by The Rizz ( 1319 ) on Wednesday December 30, 2009 @10:49AM (#30594336)

    I live in North Dakota, we've had these LED traffic lights for years, and I cannot remember the last time I saw one totally snowed up. The shields that curve over the top of the traffic lights here do an adequate job of keeping the snow from coating the signals - including during the 3-day blizzard we had last week (I had to drive in it each of those 3 days, so trust me - they worked).

    If they're not working in other states, than either their storms are somehow worse than ND's, or they've cheaped out on the snow shields that go over the top of the lights. I know which one I'd put my money on...

    • Here in Oslo (Norway) we've had these LED lights for several years, and the snow shields have never (afaik) had any problems keeping the lights visible, even during our regular snow storms.

      Here's a detail from a photo of a local junction which I took for my wife. She is responsible for making public transport in the region as efficient as possible, which includes giving priority to buses and trams in all intersections:

      http://tmsw.no/trafikklys.jpg [tmsw.no]

      Terje

      PS. Here's a link to the least useful program I have eve

  • by nsayer ( 86181 ) <{moc.ufk} {ta} {reyasn}> on Wednesday December 30, 2009 @12:18PM (#30596086) Homepage

    Come on, a thermister set for 32 degrees F and a 5 watt resistor would probably do the trick. How much could that really cost extra?

  • by laughing_badger ( 628416 ) on Wednesday December 30, 2009 @01:15PM (#30597062) Homepage
    This is an opportunity, not a problem. Pack the lights with a nice long half-life radioisotope that we want to dispose of and let them melt their own snow. That way we still get all of the green benefits of LED over incandescent.
  • by Caduceus1 ( 178942 ) on Wednesday December 30, 2009 @02:10PM (#30597910) Homepage

    Let's ignore the positional arguments for now - yes, everyone SHOULD know that the light on top is the red one, etc. But it is obviously not the case. Some people are just not that smart.

    I have always understood that the lenses which used to give lights their color, in the green case, was not really a pure green but had a tint of blue. This allowed those with green colorblindness to still distinguish the light from the others. However, it is VERY noticeable that the green LED lights are NOT the same color as the old lenses, but appear to be more of a true green. Is there a reason why they weren't made the same blue/green? Or did someone just forget?

    It may be possible, if they can't produce a blended LED, to simply include some blue LEDs in the matrix as well, which should to most of us produce a blended color.

    I have seen some red LED lights include a white flashing ring or center dot - this really brings attention to the light. Totally non-standard that I have seen though.

    With the LED matrix lights, it is now quite simple to create shaped lights. A distinctive square or rectangular (would likely require redesigned light fixtures) design on the stop light would make it more distinguishable.

    I remember the horizontal fixtures in Quebec - but I remember that the stop lights appeared on BOTH ends of the fixture - that is there were TWO lights on the outside when STOP.

    What needs to happen now is standards for future replacements and new installations so that they can be ready in the future.

  • Uuum, WTF? (Score:3, Insightful)

    by Hurricane78 ( 562437 ) <deleted&slashdot,org> on Wednesday December 30, 2009 @03:34PM (#30599138)

    Isn’t that why the simple and effective solution called a “roof” was invented for?

    Just put a box around it, with a flat, transparent, 45 downwards facing surface in front of the light. There you go. Problem solved.
    You can even coat it with a water-repelling substance, to prevent fogging.
    Gravity will do the rest.

    Oh wait... they don’t believe in gravity, in the midwest, right? ^^

  • gas (Score:3, Funny)

    by pbjones ( 315127 ) * on Wednesday December 30, 2009 @03:49PM (#30599330)

    all of our lights should be gas powered with mechanical shutters to change which lamp is visible. And we could have a small booth with each intersection that housed a person to operate the signals, giving them employment and shelter in winter. As for the LED lights, a bit of research would have helped, it's not as if the entire world suddenly woke up to find LEDs instead of incandescent globe, offs!

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