LED Stoplights Failing in Winter

LED Lights Don’t Melt Snow on Traffic Lights, Hiding Signals From Drivers

By ELISABETH LEAMY and VANESSA WEBER

Jan. 8, 2010

A huge swath of the country is getting snow and it’s raised an unusual and potentially dangerous problem for motorists.

Click picture to see report

Communities across the country are converting to LED traffic lights, but these lights don’t emit heat, so snow doesn’t melt like it would with a regular incandescent bulb. In some cases, Drivers then can’t see the signals.

During a snow storm last year, Lisa Richter of Oswego, Ill., had a green light and was turning left. But police say a driver in the oncoming lane blew through his red light and plowed into her, killing her instantly.

This wasn’t a regular accident. Police said this traffic light, blocked by snow, contributed to the crash. The light was an LED signal, which doesn’t emit heat, so snow doesn’t melt like it would with a regular incandescent bulb.

Cities and states across the country that have converted to LEDs report an energy cost savings of up to 80 to 90 percent.

In Green Bay, Wisc., where all traffic lights are now LEDs, December’s incredible snowfall caused many to be packed with flakes.

After their intense storm last month, some drivers in Madison, Wisc., noticed their neighborhood LED signals were hiding.

“I know that the stoplights are there, but if I didn’t, it would have been very easy to fly right through them,” one driver said. “And especially with the off ramp right on the interstate, it could be a very dangerous situation.”

The state of Wisconsin switched to LEDs in 2002 to achieve the massive energy cost savings. Maintenance costs are also much lower because LEDs last a long time. Incandescent bulbs usually have to be replaced every 2 years.

“With LEDs, we have some of our heads that were installed in 2002 still operational today,” said Wisconsin state traffic signal systems engineer Joanna Bush.

Another advantage of LEDs: Bush said the old incandescent bulbs could pose safety problems of their own.

“When they fail, they go dark, like a light bulb at your house. There’s no warning and it’s dark. With the LEDs, it’s a string or two that starts to go out and the driving public might not even notice a change in the LEDs and we can get our crews out to change it.”

ht JRHolm
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Son of a Pig and a Monkey

Yes, but you’ll need crews to go out and scrape ice of the lights, creating some of Obama’s new green jobs.

Tom

For what it’s worth, the push to LED traffic lights appears to be motivated largely by significant savings in electricity and maintenance costs, rather than by green pipe dreams. For once these are the unintended consequences of government doing something smart, than of government doing something stupid.

P Gosselin

“Not a problem in warm states, but a problem where it snows.”
Great! It’s only safe to install them in Hawaii!

P Gosselin

And Puerto Rico!

starzmom

Why is this a surprise? People who have used LED lights have known this for years. The traffic engineers in cities using them in traffic signals should also have known, and been doing something about it. A small heating element in the light fixture, perhaps? Sounds like a lot of lawsuits waiting to happen to me!

Mark

The easy fix is to not have the shield that collects the snow, especially since LED’s shine brighter and don’t need to have the light directed.
The more expensive fix would be to convert alot of those intersections to roundabouts. By doing so, it makes people more aware of the traffic that is moving around it. I saw an interesting story on one of the cable news stations about a month ago. Some town in Norway took down all of it’s traffic lights and replaced it with roundabouts and has improved traffic flow almost 80% and has cut down on traffic accidents.

Steve in SC

Media gets it wrong again!
LEDs do emit heat, just not a whole lot.
They are more efficient and thus produce the same light with less wattage dissipated in heat. They are substantially more visible in situations where glare is a problem. Which poison do you want?

Fred2

Dunno, how biug a problem is this really? I mean how much snow do you have to pack a LED light before you can’t see it at all, and then how many drivers really won’t stop and look around at a defective light?
As to the heating thing, it would have to be pretty smart with some secondary sensor, otherwise you are throwing away the energy savings.
I’d be worried that all that : heating element + snow pack sensor + whatever would be deeply unreliable in actual service conditions. After all lights are defintely onthe severe duty service list: water, sun, heat, cold, wind, vibration, general pollution…

Well, personally I prefer them! They’re more reliable than conventional bulbs, give a more crisp light, and use a lot less battery. It’s not too difficult to think that you need to clear snow off them before you drive off, and periodically (if you then drive through a snowstorm). I’ve seen idiots (Gores to you US) all this week in the UK who can’t clear snow off their windscreen (windshield to you US), off the bonnet (hood to you US), or off the roof (roof to you US). They are then shocked when a lump of it falls off as they’re driving along. They ought to use their loaf (head to you US).

P Gosselin

starzmom
If this was known and is known, and cities install them anyway, then they are liable for any death, injury or property damage that results. Companies could never get away with this.
If governments are allowed to, then it is yet another sign af out-of-control government power.

P Gosselin

For Americans, a roundabout is a so-called traffic circle.

Philip T. Downman

What should this illustrate? The danger of saving energy by switching to LED instead of incandescent light? How about all other traffic signs that snow over?
It doesn’t have with climate to do at all. It’s typical of the fear for all that’s not as it used to be. Father never used an LED.

LED lights are superior. We notice them going out more now because of two things:
a) failing LEDs is a rare event and,
b) a lot of LED stoplights were installed at the same time in the early oughties, when the technology first came out, and are starting to hit an uptick in failures as they near end of life, esp in harsh environmental conditions.
It is truly worth it to use LED lighting, it reduces power consumption by 90% over incandescent, and given the percent of our national electric supply that is consumed by lighting, converting all of our lights to LEDs would mean a rather large conservation.
According to this:
http://www.cee1.org/eval/db_pdf_es/275es.pdf
22% of US electric consumption is in lighting. Converting to LED lighting nationwide for everything would therefore reduce consumption overall by 20%. Given electric production is some 70%+ based on carbon emitting fuels, a reduction in emissions by 17% would put us below our 1990 emission levels for a good few years without a significant economic burden (in fact, LED’s have a ROI of under two years, so the economic benefits are actually positive).

TerryS

The solution seems simple to me. Have a small heater in the traffic light that is controlled by the temperature. Below zero and it switches on, above and it switches off. The electricity saved over using halogen bulbs (which is what I think traffic lights use) will still be substantial.

Nigel S

This doesn’t sound like a real problem, if there is no light showing then slow down. There would have to be a lot of snow before you could not see that there were lights at the junction.

Didn’t the US pass a law prohibiting the sale of incandescent lights by 2010? So maybe the local governments changed them to comply with Federal regulations…

Gail Combs

Time for the engineering types to come up with a new design for traffic lights. I am sure there are a variety of designs that could fix this problem from a sensor that switches on a heating element to an angled lens with a silicone slick coating that snow will not stick to.

photon without a Higgs

starzmom (06:26:37) :
The traffic engineers in cities using them in traffic signals should also have known, and been doing something about it.
____________________________________________________________________
In principle I agree.
But, it’s not so easy to go against the flow. Especially when the flow is supposedly saving the world.
There’s a whole lot of things going on that someone somewhere along the line should known better and said something. Some probably are saying something. But their objection alone isn’t enough to stop ‘going green’.
Going green is pretty much everywhere you look. I saw a FedEx commercial where they said they didn’t have wood tables because the went green. I saw metal in the new table legs…..(scratches head)….. I can’t see how metal is ‘green’-er than wood—but that’s another topic.
All the record cold and snow though is slowly but surely changing the momentum AGW and ‘going green’ has. But I think even if the world goes in to a modern day little ice age there will still be a small percentage of people talking about global warming and ‘going green’ to save the earth.
So, don’t be too hard on city engineers. They might be good folk.

photon without a Higgs

Record cold and snow in the past two days, Thursday and Friday, in the US. Florida is getting it the worst. But Watts Up With that red dot in Florida??
http://mapcenter.hamweather.com/records/2day/us.html?c=maxtemp,mintemp,lowmax,highmin,snow

wws

anything but new roundabouts! They used to be very popular in the 20’s and 30’s; just about every Texas town had one at the main intersection. They have just about all been eliminated now, thank merciful heaven! (I still know of a couple on the outskirts of Waco and Ft. Worth) They have always been deathtraps, I think when the Dallas roundabout was finally demolished a few years ago the death toll over it’s existence stood at about 300 or so. Sure there are yield signs and speed limit signs – I’ve been on them, still everyone enters at 70mph and just hopes a spot opens up when they get there.
In horse and buggy days, they were great -but today, they’re just a nonstop demolition derby.

photon without a Higgs

In the past 2 days alone in the US 277 cold records and 417 snowfall records.
Many roads from San Antonio to across the deep south have ice. Atlanta is especially icy.
In Florida they say they’ve had ice and frost like this before but never for this many days in a row. The farmers are going to be hurt financially by it.

DirkH

How about increasing the CO2 content of the atmosphere until all snow melts? Oh wait…

All they need to do is put a sensor which detects when temps drop below 32 and activate a resistive non-light emitting heat source. Problem solved.

Mike Monce

I generally like the LED traffic lights. However, in my area I have noted a failure phenonmenon: The greens seem to have a large number of failed, or failing individual LED’s. The reds and yellows seem to be holding up much better. I haven’t taken a statistical sample, but maybe I will in the next few weeks. I deal with atomic and molecular physics rather than solid state, but I would guess that the dopant for the greens may change the substrate such that temperature extremes are not tolerated well. Could also be the stress of constant on/off cyles.

Robert Kral

In the Christmas Eve snowstorm we had in North Texas, it didn’t take long for the LED lights to develop visibility problems. The snow and sleet were blowing sideways in strong winds. If you were driving on unfamiliar roads, as we were, the “hidden” traffic lights were a problem because visibility was poor anyway. Not a reason to give up on LEDs, but there will ultimately need to be another techno-fix to address this particular issue.

Craig Moore

What this portends is Hell freezing over when the real thing is replaced with LED imitations. Not many watts down with that.

Mike from Canmore

How much of a problem is this? I don’t know, let’s ask Lisa Richter. . . Sorry can’t. Assuming the person who hit her was sober and acting responsibly, s/he more than likely isn’t enjoying life right now.
Great that they save 80% of energy. I’d be curious what that converts to in absolute dollars. Then ask the question, how much of the cost drivers are due to politically motivated green regulations which in turn drive up the cost of electricity.
Before one thinks this is not a big problem, imagine if it occurred to a member of your family or close friend.

Gail Combs

photon without a Higgs (07:20:55) :
Record cold and snow in the past two days, Thursday and Friday, in the US. Florida is getting it the worst. But Watts Up With that red dot in Florida??
http://mapcenter.hamweather.com/records/2day/us.html?c=maxtemp,mintemp,lowmax,highmin,snow
86F when the surrounding area is 20F??? The temperature there is bouncing all over the place look at the record for the last week. http://www.wunderground.com/history/airport/KMAI/2010/1/8/WeeklyHistory.html
Is there anyone in that area that can confirm these wild swings in temp?

Alan Haile
Mike Ramsey

Entrepreneurs take note. A new product that all the northen states will have to buy. Traffic light heaters!
And the control mechanism to turn them on and off from a central control center.
Ahh, I see the cash rolling in….
Mike Ramsey

DocBrown

The school zones in our town have been fitted with flashing lights that operate during times when students arrive and leave school. Whe the lights are flashing, the speed limit is reduced in the the school safety zone.
The problem is that these lights and their controls are freestanding solar powered units.
For most of the last week, the solar panels have been covered in snow and the lights have not worked. This at a time when visibility is poor and braking conditions treacherous.
Student safety, or solar? Pick one.
[Actually there is no epidemic of students mowed down by cars, either before the lights were installed, or now. These devices are merely revenue generating devices that allow traffic cops to double the fines on inattentive motorists during their operation. But that’s a different rant.]

P Gosselin

“if there is no light showing then slow down. ”
At night they could be a little hard to see.
If you#re new in the area, then you might not see it well either.
Heck, people sometimes don’t even see red lights.
I think it’s all abunch of silly actionsm. “Hey look at us! We’re being green!”
Actually Jeff Id has a good solution…hurry up and patent it!

schnoerkelman

If there have been a large number of LED signal lamps installed since (say) 2000 and this is the first time that there has been a (reported) fatality I think the risk is acceptable. Perhaps the problem doesn’t occur often because the engineers actually did think about this? Would that really surprise anyone? I hope not.

Ken S

Maybe if they install a heating element inside with the LED light the problem would be solved. The heating element could also be so designed to give off light. Just thought of something brilliant, why not do away with the LED light if you replace it with a heater element that gives off enough light to be used as a signal light bulb,,, Dah!
Better yet, take all the signal lights down, remove all the signs and let stupidy sort it all out! There is a town somewhere in Europe that did just that, can’t remember where but the result was that the traffic flowed better and there were less accidents. The people in that town adjusted just fine, bet us americans would never have that ability.

femidav

Stop lights doesn’t produce enough anyway. So it’s just BS

JB Williamson

Mark (06:31:00) said :
“The more expensive fix would be to convert a lot of those intersections to roundabouts. By doing so, it makes people more aware of the traffic that is moving around it. I saw an interesting story on one of the cable news stations about a month ago. Some town in Norway took down all of it’s traffic lights and replaced it with roundabouts and has improved traffic flow almost 80% and has cut down on traffic accidents.”
In the UK we are doing our best to screw up traffic flows by putting traffic lights on all our roundabouts. The inevitable result of which is that some drivers just ignore them.

neumann103

My 3 year old just pointed an LED flashlight up to my eye. It does emit heat.
A few years back I put LED bulbs in the potlights in my home. It was too early. As a previous poster indicated, the current failing LEDs are likely early generation units. Newer ones are cheaper, last longer, have many more colour temperature options.
They just have to redesign the housing of the lights to prevent snow accumulation

Dan Evans

You have to consider the benefits as well as the disadvantages of a thing. In terms of human life, add up the lives saved by LEDs that replaced incandescent red lights that might have burned out and caused a fatal wreck.

Steve in SC

The solution is simple. Take a look at the rear window of most any modern automobile. What do you see? Little horizontal lines that comprise the defogger/defroster circuit. Temperature sensors that would turn them on would burn a lot of useless electricity. What is needed is a snow/ice sensor.
How about turning them on system wide when snow and ice are experienced. They don’t need defogging at 0 deg F and no snow/ice.

@ wws (07:26:23) :
How is it possible that roundabouts are deathtraps, in my own hometown (wich is in the Netherlands) we had a 4 lane road wich was reduced to a 2 lane and the intersections where replaced by roundabouts. It would not work, traffic would come to a standstill everybody cried.
Traffic is pretty much as usual, the volume even increased but what was far more spectaculair is the fact that the number of accidents with serious injuries and death on this road was reduced to almost nothing.
Sometimes you have to do the opposite to make traffic more safe and people should pay attention to their surroundings instead of racing blindly around hoping that the other driver is paying attention. If traffic lights do not work than common sense should.

Pamela Gray

Not a wild swing. The beginning of the week saw rising temps (IE a return to mild winter weather for Florida) from the 40’s to the 80’s, followed by a severe cold weather event.
Interesting how warm takes a bit to build up but cold drops in like a cannon ball.

starzmom

photon–
I am not being hard on engineers on purpose–I am one, I am married to one, and my brother, son and father in law are engineers also. But its their job to look at all the consequences and angles of the actions they take (or recommend–the engineers probably didn’t make the decisions) and lay them out. And if they didn’t know that snow would build up in the lights, that is a problem. On the other hand, maybe it was the city financial guy who nixed a heater or other fix for the problem. Either way–lawsuit.

Gail Combs

Philip T. Downman (06:53:55) :
What should this illustrate? The danger of saving energy by switching to LED instead of incandescent light? How about all other traffic signs that snow over?
It doesn’t have with climate to do at all. It’s typical of the fear for all that’s not as it used to be. Father never used an LED.
Reply
What does this illustrate? Sloppy engineering.
If the current media crisis was “Oh my there is a coming Ice Age”, someone might have considered the icing up problem of these new lights and produced a decent, VALIDATED engineering design. Instead we have lights that will fail in snowstorms and bankrupt local governments who are not about to spend money to replace the new lights they just installed a few years ago.
The cost? People injured and dead. That is not ““typical of the fear for all that’s not as it used to be. Father never used an LED.” That is concern for our fellow humans. Something the left/progressives/marxists or whatever politician is speaking is always proclaiming, but the reality of what they implement as law always seems to be far different.

Crashex

It is always interesting to see how people blame the light instead of the driver. The lawyers have us well conditioned. “It was a foreseeable defect! It’s the company’s fault! Please send money.”
Every driver should understand the traffic rule when approaching a non-working traffic signal. It’s the same whether its incandescent or LED. If you cannot see the signal light, STOP. Look for other traffic. Proceed with caution when it is clear to do so. [Everbody else is likely stopping too, so simply take turns].
Further, even if you have a green light (and can see it) you MUST check for approaching traffic an assure a clear distance BEFORE starting your left turn. The description in the article isn’t clear as to whether the vehicle going through the intersection was in an oncoming lane or the cross street.
News commentary and shows like 60 Minutes are usually presented from the perspective of the plaintiff’s lawyer.

snopercod

Re: Failing LEDs
Let’s not ass-ume that the LEDs themselves are failing. Thanks to RoHS, it could be the lead-less solder connections.

David Becker

The newly designed roundabouts are not at all the same as the old familiar traffic circles. The design is very different and a lot of the problems that used to exist with the older traffic circles have been removed. We have a couple of roundabouts here in Rochester (MI) and they are highly successful, even though there is a bit of a learning curve.

Steve Allen

Come on folks. I am ALL for being skeptical when it comes to “man-made-global-warming”, but if LED lamp installation makes economic sense, then by all means do it! I believe its a fairly straight forward economic calculation that includes well documented (averaged) costs such as; replacement frequency, lamp cost, estimated watt-hour consumption, as well as estimated electricity costs (historic). Example: my calculations for purchase of LED Christmas lights DID NOT make economic sense, in short, in my location, the cost-of-purchase + the cost-to-operate per LED lamp was significantly higher for a 5 year period than the same costs on low wattage conventional lamp. I calculated it was cheaper to buy the conventional $0.03/lamp strands, and throw them away in 5 years. I’m betting by then, LED’s will be super cheap and/or electricity will be super expensive.
Even when done well, implementation of new technology most certainly solves some problems, and typically presents some new ones. I thought the fix proposed on ABC news of transparent bubble-like shields seemed logical and probably fairly cheap.

Al Gore's Holy Hologram

Pray we do have some global warming. If cooling continues we’ll use more energy and have less energy security.

Henry chance

On new years day my daughter said “we are not there yet”
I asked her how advanced we are with LED’s. She is an architectural engineer and is over 1 billion dollars of construction in the design phases.
LED requires new lighting fistures and products. Just changing bulbs without re engineering is not working well.

Philip T. Downman

LED is the future. There is already technology for increasing brightnes and improving colour. http://www.obducat.com/Default.aspx?ID=87. Gas lights would perhaps melt ice better than incandescent bulbs?
Peasant conservatism has to be overcome.
Until something even better emerges.
Bad technology and sloppy engineering should be replaced by better technology, not with retreating