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Midwest Seeing Red Over 'Green' Traffic Lights
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.
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.
Oh, I thought the law was clear - when the signals are obscured or not working, stop at the intersection and then proceed as per a normal crossroads.
Green lights are actually quite blue so that R/G colourblind people don't have problems, this shouldn't be an issue with the LED lights either.
Adding a heating circuit that only operates when cold is still more efficient than the old bulbs - it's only on for a portion of the year, and it's more efficient at turning energy into heat.
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
If they didn't look different, you wouldn't be able to distinguish them.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
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.
someone is just looking for a scapegoat. see a light standard, no signal/flashing YOU STOP
If only there was a slick clear material http://en.wikipedia.org/wiki/Glass we could put over the front of these round tube things depicted that snow wouldn't be able to adhere to
why not include a heating element within the lamp that will only turn on when it's ~35F or below? That way you get the best of both worlds?
why don't they just angle the lenses downwards with less of a hood? problem solved.
Put a small heater in the traffic signal that turns on below 0C (32F). Problem solved.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
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?
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
A lot of traffic lights in Canada are of the LED variety. I've never seen one obstructed by snow.
It seems the obvious solution is to remove the shroud surrounding the LEDs. The LEDs are bright enough and directional enough to not need a shroud, unlike the incandescents.
Remove the shroud, the snow has no place to accumulate and the lights can be seen. Everyone is happy.
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!
Any sufficiently advanced influence is indistinguishable from control.
use a non-stick, non-freezing lens for the lights.
also add an anti-glare coating too so the light covers arent deep enough to catch snow, with a slightly dark color.
note that a good portion of that black light housing has already melted.
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?
You see? You see? Your stupid minds! Stupid! Stupid!
After having lived my first 30 years in Florida and now living in Ohio the past 10 I have a theory about Northern drivers. Besides the equipment issues like LED traffic lights what do cold temperatures affect? Hmmm...
We know that your bladder shrinks. We also know that your blood vessels constrict. That would include blood vessels feeding the brain. And that's why the drivers around here are so damn bad during the Winter. They are inherently stupider! So please fix the issue with LED traffic lights, as any additional handicaps are adding fuel to the fire!
Tell that to the surviving members of Lisa Richter's family.
'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
I saw a TV new report on this issue yesterday and the new design shielding the light had a gap to create a flow to help prevent build-up.
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.
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?'
people shouldn't be trusted with automobiles anyway
The problem isn't the new bulbs themselves. It's because the light fixture is designed with the old bulbs in mind.
They need new fixtures that are made for LED's and account for problems like lack of heat (eg. they could design it so that snow does not collect in front of the lights).
My town mistakenly ordered IED lights. These remove their own snow.
If Slashdot were chemistry it would look like this:Cadaverine
http://www.worldofstock.com/slides/MES2459.jpg ...to make it appear as a circle, exactly?
Unless the driver was saying "you know, I couldn't make out the shape at all.. it just looked like -a- green light, and that was good enough for me", of course.
Amazing, the real world isn't like the lab. And, surprise, all of the theoretical results expected aren't going to be achieved in the real world. This is a great example of theory meeting the real world and should make us pause and reduce our expectations for benefits of going green. Yes, it is a good idea to reduce our energy consumption and carbon footprint. Bu no, we won't get the results in terms of energy savings, reduced emissions and job creation that the ardent proponents are telling us will be achieved and it will take longer than expected. Still worth doing, but don't believe the press releases and promises.
Has anyone studied the impact of so many small sources of heat on the changing climate? Here we have a tiny example, to be sure, but changing the type of lighting in the streetlight has impacted the climate around that light so much that snowfall is now an issue where it was not before. If everyone everywhere stopped using incandescent bulbs and switched to LED's that (for the sake of argument) used exactly the same amount of electricity, what would the impact be on our environment?
In that vein, there are billions of humans on the planet who insist on keeping their immediate climate around 72 degrees throughout every season. Every time their immediate climate touches the global one, a micro-transaction of heat occurs. If this completely stopped, and for the sake of argument humans didn't die because of that, what would the impact of this be on our environment?
Finally, with all those billions of humans themselves being chemical engines which emit heat as a by-product (as evidenced by my cat's behavior this winter), what would be the impact of reducing their body temperatures to, say, 80 degrees?
If all of this doesn't somehow add up, I'd like to know why. I am genuinely curious... And for the sake of discussion, I'd prefer to leave the political BS out of it. I'm genuinely interested in the science behind it.
This is a simple problem that can be solved with a small amount of engineering and a little common sense. Obstructed traffic lights do not cause accidents, poor/unattentive drivers cause accidents. You should always be aware of the surroundings and be ready to react. I always look both ways when crossing a one way street, because it is the reckless driver going the wrong way that causes the problem. Yellow light means prepare to stop (and clear the intersection), not speed up to cross (or enter the intersection).
The US NEEDS to expire driving licenses and require re-testing every 5 or 10 years. Plus there needs to be stricter testing. This will keep unsafe drivers (yeah you grandma) off the road.
BTB. No, not "Business To Business" (although in a sense it is that), I'm referring to Biting The Brown. Tossing Salad. Going down on the brown. Mouth-To-Ass. Read the wikipedia page on rimjobs. Not the article, the discussion. A handful of editors have decided that there's no such thing as "biting the brown" and delete any reference to it. Sorry jimbo, I'm not giving you jack shit while shit like that is going on.
Well imports some lemurs to cuddle up next to each stoplight to keep them warm. In addition, they will get rid of the Australian cockroaches that were introduced to help with the stray breadcrumbs in the parks...
Then this would confuse people, because, you know, they're so used to the round traffic light design.
One of the smarter things in Quebec province is that many of their traffic lights use shape as well as color to distinguish between the three states. One is square (red), one round (yellow), and one triangular (green). While differing shapes increase discrimination only slightly over the differing colors, it is an increase in suitability for purpose. Also, since each light fits into the same "bounding box", this means that in area of the light, red > yellow > green, which is also a small bias on the side of safety, making red slightly more visible in adverse conditions.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
I'm from Wisconsin and we got about a foot of snow twice and I did some driving. You can still see the signal lights just fine. Snow is made out of ice which makes it translucent and the colors come through perfectly. It sounds like, as usual, people are driving with their heads up their asses in the snow and making up some BS excuse about why they went straight through a red light. Don't believe a word of this.
Google's Super Secret Search Algorithm: SELECT @search_results FROM internet WHERE @search_results = 'good'
Just put in a heater the runs at the appropriates times.
However when a traffic light is obscured, it is the drivers responsibility to proceed with caution.
The Kruger Dunning explains most post on
__R__
LY NY
LG NG
That's a common traffic light configuration for a left-hand turn light in addition to a normal light. (L / N stand for left / normal).
__R__
NY RY
NG RG
That's a common traffic light configuration for a right-hand turn light in addition to a normal light. (N / R stand for normal / right).
If they were obscured in a diffuse manner, perhaps you can see the issue that arises for somebody unfamiliar with the intersection.
SIG: HUP
install a low power heating element over the lights to warm them up in the winter. you still save power because you don't need them in the summer.
They're using their grammar skills there.
Um ... if the old lights were hot enough to melt snow and stay visible in a blizzard REVERT TO THE OLD TECHNOLOGY! Clearly the wasted heat wasn't exactly wasted if it served a useful purpose. Why waste all this money coming up with these crazy schemes for getting snow off an LED when a regular old hot incandescent has the functionality you need BUILT IN?
Energy savings apparently wasn't the only factor that should have been evaluated when deciding to change lights.
damaged by dogma
Other than that I would say when you are unsure about the light YOU treat it as a 4 way stop and do not assume the other drivers are any good. Worst case is blast those bad drivers with the Flame thrower equipped truck!
We've never been able to rely on incandescent heating to clear the lights. The fixtures are designed not to accumulate snow and when they do get obscured, the rules are clear: stop and proceed with caution.
Its not rocket science.
Make the green light (which is supposed to be on the bottom) an incandescent light. Make the yellow and red LED. The heat generated from the one light will keep it from attracting ice. If it's obscured, people can't tell what it's doing, and it becomes an automatic stop/hazard situation.
Also uses 1/3 the power of an all-incandescent solution.
Help! I'm a slashdot refugee.
How about encasing the lights in a large Plexiglas oval bulb. The snow should just mostly fall off and as long as the housing unit of the light is black, the heat created by radiation should assist melting any snow on the top of the Plexiglas bulb. Now, I'm sure there would be issues with this as well, but it could be a possible solution.
There are no loopholes. It's either legal or it's not.
This is an easy easy easy fix. replace a percentage of the leds with IR leds to generate some heat
Not green bashing, as it is devolving into? It sounds like the old design had some largely unrealized benefits. This doesn't mean that LED street lights are universally crap, or that 'green' thinking cities are dumb. It is about a feature of the old design that was unrealized. Changing a design frequently means you find features you didn't realize you had in the old design. Those features weren't looked for by the cities, now they need them. I'm not sure whose fault this is. Although if the manufacturer realized it ahead of time, they would probably develop a snow proof/melting version and charge a bit more for them, and advertise the heck out of them to the appropriate audience.
It does however bring up a new 'feature' in traffic lights that I've been noticing. They seem to be pushing limited angle of view models onto the streets around here (N. TX). A reasonable idea if implemented well, but many are set up such that you cannot see the color of the light until you are precisely at the limit line, meaning you need to make the decision to turn or not blind, or come to a complete stop on green. Really annoying. Also, I've noticed some of the new models have the opposite problem, too reflective, such that when the sun is setting, there is a red light that is brighter when not lit, than the adjacent green when lit. It has the result of the driver seeing both red AND green lights at the same intersection.
Basically, these things end up being more than glorified light bulbs, their design turns out to be a little harder than the arm chair engineers might have expected.
Of course the frequency of seeing LED lights with a portion of the LEDs out, after less than a year in service, suggests that there are also some quality issues out there to work out still.
-sk
Here in Canada we get a fair amount of snow, from time to time, and we do have those LED street lights in quite a few places. Yet, in 8 years of driving, I have _never_ seen this snow covering problem. Either I've just been really lucky, or there must be a difference in design?
Our traffic lights all have round pieces of metal over the top of each light (like the brim of a baseball cap). I always assumed these were there to prevent the sun from glaring off the light and making them impossible to see... but maybe it is in fact to keep the snow off?
I also always assumed these little 'hats' were universal across North America. Do they have these in the Midwest?
-hps
This is just highlighting a design flaw in the lights that incandescent lights had been masking. The obvious solution is to redesign the traffic signals so they don't accumulate snow. If you look at them now, they're buckets.
We have LED lights all over the place. Keep in mind this is the fucking ice and snow kingdom now... Sometimes stop signs get completely covered in white gunk.
So in a land of ice and snow that covers everything in white shit from hell, we had to come up with a genius little device.
Wait for it...
Wait for it...
You're gonna love this one: A fucking roof.
No I'm serious, our lights have a little tin projection. Like a cylinder cut diagonally so that drivers can see the light and bird shit (or snow) can't hit it.
Need a picture? http://en.wikipedia.org/wiki/File:Modern_British_LED_Traffic_Light.jpg
Yep it's British and probably has a hidden CCTV camera in each hood but same idea.
We even have electric heaters in/on our oil pans to pre-warm engine oil. Nifty eh?
http://www.engadget.com/2009/12/17/led-traffic-lights-dont-melt-snow-do-cause-accidents/
-_-
Cameras have had the same problems years ago and there are plenty of solutions on the market. Someone just need to do some research, I guess... Just my 2 cents...
I'm a "do something about GW now" skeptic, but even I can see that the LED lights are better. Way less energy usage, and the colors are much, much more distinct due to being nearly monochrome.
It seems that lights in the mid-west however were not properly designed. You can't just take a stack of LEDs, stick them on a PCB with a current-limiting resistor and call it done. Especially if you're going to be charging real money for the lamp. You have to consider the requirements of the application you're installing them in.
IOW, if it gets cold and there is snow, then you wind a wire through the PCB to use for active heating when it gets cold. A robust, but somewhat wasteful mechanism would be to use a temperature controller to maintain a degree or two above freezing: snow and icing would be prevented, increasing the longevity of the light, at a cost of some wasted volt-amps during the winter months. More savings could be realized by adding a "snow expected" flag to whatever control system runs the lights. And cop time could be saved if it could be set remotely.
This is a design problem, not a "green tech" problem. Unless you accept the premise that all "green" tech must be the most naïve implementation available.
Can you be Even More Awesome?!
Signs will get obscured in snowstorms, whether it's a traffic light, speed limit, left lane must turn left, etc. Part of being a licensed driver is being able to understand and implement the rules of right of way to avoid problems when the usual control systems aren't available (okay - and also when they are). Tighten up US driver's licensing like Europe's, and I doubt these problems would be as severe.
It may well be that in some circumstances LED bulbs are not suitable, or need to be augmented by heating elements, but if they are more reliable at other times they may be safer overall.
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...
While I can't say that this is a solved problem, it does appear to be a common one, particularly where it's cold / snowy. I'm betting not too many people from Arizona are in on a solution.
This person has prototyped a solution for LED vehicle lights as well as traffic lights (makes sense as they suffer from the same problem) - heated traffic light lens
Some problems are hard to anticipate when implementing a new solution - this wasn't one of them. If you live in a snowy climate and want your traffic lights to work even during snow, you MUST take precautions.
It doesn't sound like a terribly difficult problem either. You could use heating, some kind of automatic wiper, spraying with ethylene glycol, or just wiping them off manually every now and then.
It seems to me that building in some sort of new heating device to melt the snow is *drastically* overthinking the problem. Why not just put some sort of cap/window over the light so the snow can't settle INSIDE on the ledge part?
or a not-visible light is a 4-way stop.
where drivers weren't sure whether to stop or go
Only a complete idiot would simply drive through an intersection with an impaired signal without stopping and checking for traffic. The US needs higher standards for awarding Driver's Licenses
I still cannot find the droids I am looking for...
How many people get red light ticks from this?
Even if you act like it's a 4 way stop you can get hit with a $100+ ticket.
You don't have to put on the LED light
So, why does snow accumulate on the lights in the first place? Because there are nooks and crannies where it can land. Eliminate those, you get rid of a lot of the problem. Next, snow and ice accumulate because the water is just above freezing, and the traffic light is below freezing. It hits, freezes, and sticks. Reengining the shape of the light won't fix that, but common sense of the part of drivers will. If approaching a traffic light and it's indication isn't clear, treat it as a stop sign.
But no, too many drivers would rather cripple or kill others because they are in a hurry...
Necessity is the plea for every infringement of human freedom. It is the argument of tyrants; it is the creed of slaves.
Really? this was all over the news a month ago. I hate seeing old news in my feeds, and 90% of it comes from Slashdot.
What happen? you used to be cool.
Yes, it's true: if a traffic signal is obscured by snow, treat it like an all-way stop. I live in Florida, so all we have are blacked-out traffic signals during power failures.
But there's a danger:
Fast north winds mean the southbound signals are covered with snow, but the other directions' signals are visible.
You're driving south, your signal is covered with snow, and you are unaware that you have a red light. You come to a complete stop, treat it like an all-way stop, and keep going through the intersection. The cross street has a green light, and it's crash time.
This is also possible if the right lights burn out in the wrong combination. LED traffic signals are more reliable in this matter, so there's a safety improvement right there.
As for snow and ice melting, I assume that outfitting LED signals with heating devices thermostatically set to 36F is a LOT cheaper than switching back to incandescant beacuse of this "advantage". Even if you live in the coldest climate, you're still better off with fluorescent lighting at home, since incandescent lights are wasteful lights AND wasteful heat sources.
"...leading to crashes at intersections where drivers weren't sure whether to stop or go"
Quote this article to Intelligent Design freaks as proof that evolution is alive and well!!
=D
So, if you lose energy efficiency by adding heating coils, the "brighter (safer)" and "longer lasting" don't give enough reason to buy?
this is a design problem not a green problem. Simply retrofitting LEDs into old designs was a mistake. LEDs don't have the same reflective properties as regular lights and dont need the covers that create most of the problem here. As said before in northern climates we should add a low power heating element, make the whole design smoother to reduce build up ( that would also reduce motion and strain induced by wind ), make them black (also increases contrast) and chemically coating them to prevent build up.
Note - power usage is not really an issue here. LED lights are not being installed for energy savings. Sure that comes with the package but the real savings is replacement cost. While a LED bulb may cost just as much as the 6 regular bulbs it will replace in its life, that is five fewer times you'll spend hundreds of dollars sending a crew and a lift truck out to replace the bulbs.
weather 1 side of a light or the entire thing is not working correctly you stop. in case of a total faller you treat it as a 4 way. most drivers are very careful around a failed single. in case of one not working on 1 side you treat it as a flashing red single witch means stop until its safe to go. and if you report it they will send a traffic officer out to control traffic
As I'm not one to bitch and offer no solution, here's one... suppose we start by placing conical lenses over these things. Snow may cover the top, but I doubt it would cover bottom and sides.
On the other hand, perhaps it is time to ditch the RED/YELLOW/GREEN system altogether, and come up with something more effective. So many drivers are talking/texting on cellphones while they're driving now, (even in many places where it is illegal to do so,) maybe the system should simply detect from the signals from the phones what their numbers are, and send them a message.
"... yeah, I'll come to Cindy's birthday pa... wait, I've got a message coming in... OH SHIT OH SHIT OH SHIT - A RED LIGHT!"
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
Terje
PS. Here's a link to the least useful program I have even written, pi-search, which can locate digit strings anywhere within the first 1e9 digits of pi:
http://tmsw.no/pi-search/
"almost all programming can be viewed as an exercise in caching"
BadSummary(TM) The dead woman clearly couldn't contest the accident. The clarity in writing these days is deplorable.
Think about it. Attaching a sort of overhead fixture to the lights or even wrapping the lights together in a rectangular box with the side displaying the light left open to shield them from the troublesome snow...
Surely I'm not the only person who thought of something like that...
I know the cost factor is an issue, but which costs more: paying a bunch of drivers who are suing you because of the safety hazard or spending a little bit extra, which obviously adds up, on protecting the lights to allow drivers to be safer? Not a difficult question in my opinion, and it should still be cheaper than going back to the old lights that didn't have the problem and costed a lot.
the snow piled up on the lower edge of the sun shield should reflect back way more of the LED light so they just need to add a simple circuit( micro ) to use a few of the existing LEDs as sensors and if snow is sensed, temporarily enable either a heating element/resistor or figure out some way to add a little more heat to the current operation.
this only uses extra power when needed but it does require a new design. IMO the companies who sell these LED lights as a full kit should pay for this since it is a design flaw because it does not replace the existing/old lights features.
LoB
"Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
...which calls for a technological solution.
Looking at the light in the article, changing the shape of the hood or similar passive solutions probably won't work; the vertical metal sign is snow-covered despite no snow-trapping surfaces. So it's going to need to be an active solution. Heat and vibration are two choices. Vibration might work, but vibration + electronics is often a bad idea; you might vibrate your LEDs loose as well as the snow. Plus a heater is likely going to be more reliable. So the next idea is how to turn it on. Manual solutions are possible but an automatic one is desirable. Easy enough not to turn it on when the lens is above 32F, but you also want it off when the lens is unobscured but cold.
Seems to me one way to do this is to measure the reflected light. Include two photosensors. Both should be on the inside of the lens but shielded from the LCDs themselves. One should have a filter which blocks light except in the LCDs color. The filtered sensor measures reflected light. If the lens is obscured by snow, the filtered sensor signal should be high in absolute terms and similar to the unfiltered sensor signal. If the lens is clear of snow, the filtered sensor signal should be much lower than the unfiltered sensor signal during the day, and low in absolute terms at night.
ANy engineer planning for outdoor products in the midwest that didn't consider weather extremes needs a kick in the junk.
Same with all "green tech," with a direct comparison: CFL bulbs. "Yay! It's green cuz it uses less energy and can last longer!" But it takes more energy to manufacture the bulbs than a normal bulb consumes in it's lifetime, not even to mention they put out crap almost blue-only light that gives people headaches AND polute the earth with mercury (unlike regular bulbs)!
(Sarcasm)Great Idea!(/Sarcasm)
This kinda stuff has politics written all over it. Just to relate my comparison in case you somehow ignore it: The traffic lights gained the political figures favor for saving money, but they didn't care about the fact it might cause deaths. Likewise, CFL saves money, but they didn't care about the fact it might cause mercury pollution or decrease actual visibility.
I'm not saying "green tech" is bad in general, just that it is almost completely a politcal movement now and being handled accordingly.
"Just because he can't see the light doesn't mean he can drive through the intersection without due caution," Richter said.
That.
... that the main savings involved in replacing incandescent signals with LEDs isn't the energy - it's the expense of having to pay someone to replace those bulbs when they burn out, over and over again. LED bulbs last practically forever. The cost savings in bulb replacement has been a bigger factor than energy savings in driving the move to LED bulbs in signals. I'm pretty sure you could add a tiny heater to the signal enclosure and not make much of a change in the expense of operating the thing, anyway.
How about a hydrophobic coating on the lenses, or... put the stoplights inside the cars. A system would have to be come-up-with for signalling the cars in a fool-proof (or at least fool-resistant) fashion, letting a car in any given lane know when it is approaching a red-light, and indicating this to the driver. Not sure how that would work, but it allows some interesting possibilities, like telling a car the light is red based on the car's speed and position, (knowing the car can't make it in time), reducing collisions at intersections. The same tech could be put in busses and trucks to let them know when a train is approaching. Wouldn't have to be expensive either.
The real money savings comes from the fact that you don't have to replace LED bulbs anywhere near as often as incandescents... and you'd still be saving that money, even if you installed a tiny, cheap heater in each fixture.
More brain power than the average driver has to figure out that if you can't see the signal, perhaps you should fucking slow down or stop before proceeding. Oh wait, never mind, these must be the same people who claim they have no problem paying attention to driving while talking on their cell phones.
O (red)
O (yellow)
. (green)
You mean like UK traffic lights? These do sometimes get covered a little by snow but rarely get completely covered over despite the snow being very wet and sticky. Of course the other helpful thing is that the temperatures rarely stay below zero for too long so any snow covering will last a day at the most. However, even up in the north where the snow sometimes comes in almost horizontally I've never seen a covered light, even with the new LED ones.
Let's mount some laser guns in the car, and use the windshield mist control to fire up a beam that melts the ice.
Burn FAT not OIL
Just do what normal traffic lights do to keep birds out, cut out the bottom part. No more snow, and it will cost less to make. ...or am I totally off here?
Red-green colorblindness should not affect the ability of a person to correctly observe a traffic light. The placement of the three lights is standardized as to position as well as color. Why was it mentioned in this context?
"I believe in Karma. That means I can do bad things to people all day long and I assume they deserve it." : Dogbert
Have the light lean forward when a good bit of the time they are strung from wires above.
There is an easy solution to that - don't hang your lights from wires way above the road so that the driver in the front car has to lean forward over the dash board to see the damn things. One of my pet peeves about driving the US is how awkward it is to see the lights at some junctions because they are so high. Indeed the first time I drove at night I almost ran several red lights simply because my eyes were on the road and the lights were suspended well about it and not where I was looking. While I was there for several years and got more adapted to it but they are still harder to spot than lights on poles at the side of the road.
Why not make these purple or blue. Maybe make them blink in the direction they point.Any of these would tell the driver what was up.
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?
Some reason why cold climates where this is a problem can't switch back? All these other solutions burn more energy and produce more pollution than sticking a regular bulb back in the stoplights, and voila, problem solved.
Um, you can't look for evidence of Taco being retarded here. Rather, in this instance, he's more clever than you. He's made a pun on "green" meaning energy efficient as opposed to literal color. The inefficient lights had a side effect of melting snow/frost build-up. That side effect was not considered when they were replaced with efficient ones. Thus the reason we grown-ups are here talking about it instead of, at least in your case, contemplating gay oral sex.
I was working with a company doing LED replacements for traffic signals at least five years ago, and people knew about the problem back then. And folks were going through all the gyrations mentioned here, and then some.
Rule #1: Mother Nature always wins.
Apparently those lights are not designed to work in the area they are used.
Change them to lights that are designed to work in your environment.
Well, besides, you're not going to even lose that much energy efficiency with the heating coils - you only turn those on when it's cold out. So that's half the year right there where they won't be on.
ok -- so this technology has failed.
since the savings is from the energy use of the bulb, one solution would be to have LED and incandescent bulbs together, and switch when necessary.
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In fact, we have had them for several years. I know that they have them in Norway as well. In my experience they never get fully snow covered, because they are protected by protruding tubes. Sometimes half-tubes if you need visibility from underneath. See, for example (maybe not the best angle): http://sv.wikipedia.org/wiki/Fil:Led_traffic_lights.jpg
A light bulb that will not only produce light, but also give off heat and melt the snow as it attempts to accumulate. Oh wait...
Opinion:=TMyOpinion.Create(Me);
Errr.. How about an A-frame lid on the light so the snow can just fall off.
:T:R:A:N:S:
Why not just put in Infrared LEDs in the mix as well. That would heat up the light to above 0 C, and alleviate these problems.
Going by your comments in this thread, I have realized that you are not only a rampaging iphone fanboi, you are a complete idiot. (Ah... I love redundancy!)
Give it up, man. You are just talking nonsense now. Our winter is not as good as your refrigerator.
> The Inuits (you know, the guys whom entire daily universe is either Snow or Ice...) have over a hundred words just for snow.
Not really. That's an urban legend.
See
http://www.mendosa.com/snow.html
and
http://en.wikipedia.org/wiki/Eskimo_words_for_snow
Mod down people who tell people how to mod in their sigs
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.
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Setup an A-B type of switch and have the 'Non-Green' lights on A for use in the winter.
Then when winter is over throw the A-B switch to B for 'Green' Lights to use the rest of the year.
You might not save as much money in the winter, but you'd have a mostly maintenance free solution.
The lights get covered with snow because of the cover of the lower bulbs.
In a bad storm, one with a snow fall greater than the thermal capacity of the lights to heat up the bulb shield, snow piles up.
Now that municipalities are using LED lights, the thermal capacity in almost nil.
BUT LEDs are's subject to the omni-directionality of the incandescent bulbs they're replacing so the shields aren't required.
Its a problem of retrofitting without having considered that the replacement LEDs need to be sunk in, covered with a glass plate and come flush with the edge of the old light box.
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The problem is lazy engineers who just changed the bulbs used instead of taking into consideration what that change would do to the total design of the traffic light. A good engineer would understand that without the extra heat produced by the old incandescent bulbs the design of the traffic light would need to be changed to prevent snow buildup.
Perhaps this is just a big conspiracy to help boost PVR sales? :P
"The first time I got drunk, I got married. The second time I bought a chimpanzee, after that I stayed sober" Arian Seid
A probably quick and easy fix, while maintaining a high level of energy efficacy would be to put a small heater attached to a Satellite receiver (IE; Pager) that can receive simple commands such as "HEATER; POWER ON, TIME; 1HR". Give all the receivers in a discrete area (say a county or city) their own ID and let the local Road Commission decide when and how long to turn them on (Yes, I know, some type of authentication system would be needed but thinking basics at the moment). Power might be an issue seeing as how I don't think there is a constant ON circuit to most street lights but you could tie into the positive leads on all three lights and patch in a capacitance circuit to handle the power spikes/drops between light switches. Of course the best case solution would be a light which would realize it was being covered and turn on its own heater for just the length of time needed to clear the blockage, but unless such as system has already been developed and tested it would probably take years to make sure a newly developed system would work in all reasonable conditions. Such as system could also negate the power efficiency gains in added system cost and power usage for the detection circuitry.
They also seem to be built poorly. Many of the ones here in So Cal have individual LEDs out. I'd suggest poor weatherproofing, but we so rarely have any weather.
If the traffic lights are non functional, proceed carefully through any intersections, being alert for traffic and other dangers.
Actually, bulb replacement costs a TON of money - I forget the cost I heard at a city council meeting when discussing the switch but it was more like $900 per light (they'd do all 3 because it was cheaper.) It also involved TWO city workers for some reason to replace it; safety rule I suppose. The whole city did not have enough lights to keep these workers busy just doing that; they still had to hire extra staff (I guessed it was 1 person) and the labor cost spread out over the year for having 1 extra staffer made it come out high for the labor. LED saves money.
If you want, buy bulbs WITH IR heaters in them! it'll take some work to avoid wiring them in... and the bulbs will cost more... the power use is still a problem... but less than running all year around. A cheap chip in each bulb could turn on the heat below freezing; a pulse sent to the bulb could turn it on/off as well; the whole batch could be wired up to a chip or switch on the pole... Longer lasting and cheaper-- use a heating element in the fixture to do all the lights at once (a toaster heating element should be enough.)
How about a special truck? they love buying special trucks... Better yet, have an addon for the plows to blast air at the lights when it drives under them? (not fool proof but it would reduce problems cheaply.)
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Thanks. That was informative. Wish I still had the mod points that I lost.
"No fear. No envy. No meanness." Liam Clancy
Some enterprising company could come out with the dual bulb traffic light, or even just replacement dual bulb modules. Most of the time it runs LED, whenever the weather gets icy snowy inclement it gets a signal from the traffic control overlords and switches to normal hot incandescent. I've seen flashlights like this already, so it can be done.
Isn't this a problem with stop signs? Don't stop signs get covered with snow?
Wow. Nice random bigotry. Maybe when you achieve a mental age greater than 3, you'll understand that broad brush comments are never correct.
Now with individuals you can find firmer ground, such as the fact that you are a useless, ignorant sack of pig shit.
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.
People build traffic lights that are designed to catch snow.
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.
rm
Sci-Fi Storm
You switch to LEDs to save energy, changing back strikes me as failing to address the root cause, temperature.
Where I live we have a couple of awkward corners so they mounted mirrors to allow people to see oncoming traffic. As we get snow, those mirrors have a built-in heating element that only switches on when it's cold - precisely the right idea.
If I recall correctly, there's also a self-regulating tape which is used to be embedded with water pipes to prevent them from freezing, so it's not like there aren't any solutions.
Just going back to wasting energy ALL THE TIME is mad IMHO.
Insert
"1) Being 'stupid' is subjective." Unfortunately, your point fails because being incapable of correctly navigating an intersection makes you stupid by any standard even the most subjective. "3) Labeling this behavior as 'stupid' implies both an acceptance of the inability to change it AND an implicit protection from the consequences of their behaviors" No, it doesn't. These are assumptions you're making based on your OWN biases, and they have nothing to do with op said. How did this garbage get modded to +5?
How about by weight? If the signal housing weighs more than it should activate the heater.
Why would energy use for melting the snow be an issue? The heating element doesn't need to be on all the time. It could be activated by a photocell (obviously there would have to be some sort of provision for night time in that), or remotely by radio control, or periodically when the temperature drops below freezing, or only during certain months. Over the life of the light (the thing wouldn't even come on at all 2/3 of the year in most places), the energy cost should be negligible. Incorporating it into the design of future lights might cost what...10, 20 bucks? That barely eats into the savings of going with LEDs at all.
And put back the old ones. If the lights aren't 100% reliable, then what is the point? Save energy? I can put in a stop sign that won't use any energy if that's the first priority. But if I want a signaling system to be more (traffic) efficient, they better work and work safely. Otherwise it's a stupid idea. Put the old ones back I say. They did their job.
It's actually scientists that have hundreds of words for snow.
Having lived in a place where the average snowfall was 280 inches, I suspect that like the rest of us, by about late February, they have only one phrase for snow, and it's not nice.
If the LEDs work just fine without causing trouble in Norway and Sweden they should do well enough in the midwest. It's not the LED's fault some idiot government body fucked up their implementation.
If it matters, I live in Illinois and am familiar with these lights. It bothers me how this is another instance of everyone beating the "newer is better!" drum, where dumb decisions then get made.
Why would you change a traffic light system that is time-tested, and has worked well for decades? It's almost comical how they thought that "the new system would save energy and money!" For starters, Illinois is in debt, and struggling to balance their annual budget without rasing taxes (which the governor thinks will have to happen anyway); but, they gave out $10,000,000 to rip down working traffic lights to put these up. Fantastic. Why not tear up my sidewalk too and put in a sidewalk with a newer concrete formula. Secondly, what do we do with these old, working systems? Landfill? Great; sounds very "green" to me. Even recycling them costs energy/money. Thirdly, when a repair is needed, which do you think is cheaper, some on/off electronics/relays or PWM LED drivers? (Just a thought, when you see flashing reds after a storm, it often means a power surge has taken out the controller system.) And which is cheaper, a new light bulb, or an entire LED array where one LED has failed? Fourthly, if you RTFA, a city of 30,000 ends up saving $50 a month in electricity. $50?! That's not worth lifting a pen to sign a work order! How much is that city going to save (again RTFA) when they dispatch the workers (24/7 no less) to occasionally knock the snow off the lights? So, once or twice a year and all of those savings are blown! Putting heaters on them makes the system more failure prone, more complicated to deal with, and will cost the same money as just a bulb!!
And if you need a "fifthly", I've seen no less than two of these lights in different cities flickering in sub-zero weather. The LEDs (or their supporting electronics) couldn't hold up to the cold.
I say leave the simple and old alone... Make your "improvements" elsewhere in the world.
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? ^^
Any sufficiently advanced intelligence is indistinguishable from stupidity.
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!
There was an unknown error in the submission.
(1) A story like this is a good candidate for the understatement of the millennium, given how many billions of lives the new environmentalist religion can destroy as it clips the wings of the human civilization and leads to a totalitarian dystopia from which humanity may never recover, but it's nice to see more little stories like this making it past the censors. Is the bubble finally bursting? Will people finally start crunching the numbers objectively and realize that the sky is not falling, and that the politically-motivated cure is tremendously worse than the alleged disease? If so, then the Powers That Be may need a new "enabling event", a crisis to justify maintaining and expanding government power over mankind...
(2) We wouldn't even need traffic lights in a government-free society, because of all the innovations that private ownership of transportation infrastructure would bring. Even before traffic lights were popularized in the beginning of the 20th century there were experiments with peer-to-peer signaling systems ("I yield to you", "please yield to me", etc) by the same people who invented turn signals. Just imagine what modern high-speed wireless communications could do - the cars could literally drive themselves! But in absence of the government-enforced energy famine and trillion-dollar wars for slightly cheaper oil, we'd probably all be flying (yes, flying) around at 400MPH in post-atomic-powered RV's by now!
If the LED's can handle additional current, what about a dimmer switch? If they can crank it up so it temporarily uses as many Watts as a normal bulb, it should generate the same amount of heat. Even if they can't get the power that high, higher brightness levels may be enough to be visible through the snow.
LEDs themselves don't generate much heat, but the power conversion and driving circuitry do. It doesn't seem to me that it would be that difficult to route this heat to a heat sink on or around the LEDs and/or lens.
LEDs do generate a fair amount of heat. In an incandescent globe, a lot of the generated heat comes out through the front glass, melting the snow.
In an LED light cluster, there are heatsinks on the back that bleed off the excess heat. If you open up one of these new-fangled LED traffic lights, I guarantee that there will be a heatsink in there. All they need to do is design them so that the heatsink can, using heat pipes or something like that, channel the heat out the front of the traffic light - maybe have the heatsink attached to the shield above the light that is trapping the snow...
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I live in Kansas City and here the traffic lights have a black cover coming out of it that not just makes it impossible for snow to get to the light, but also creates a shadow to make sure the sun light doesn't make it seem on when it's off.
We have had LED traffic lights in Sweden for over 10 years now.
I have never seen one blocked by snow, and never heard of any cases where there were problems like these.
And we get plenty of snow here.
Sounds like the Americans are just buying crappy lights, or maybe the wrong models.
LED lights have also been replacing incandescent at airports. Unfortunately, these lights do not emit heat energy to be picked up by FLIR cameras that you find on high end business jets.
I live in the area the original article came from. I've owned two Ford Explorers. The first was totaled when a drunk in a Neon ran a stop sign in front of me. I almost missed him. I drove the second one until the engine finally died. I liked how both of them handled in snow better than the car I now drive does. The problem with SUV's (and four-wheel-drive in general) is that many people who own one think they can stop better than a car. They usually learn different by running into someone. And as for the rollover "problem", what do people expect to happen when the left rear blows and they slam on the brakes while sharply turning the steering wheel? (Note -- I had the left rear blow and had no problem controlling the truck. I just didn't react stupidly.)
The reason this was news here (I live in the West Bend area) was because this was the first time the snow stuck really badly to the LED lights! People didn't really have much trouble with it -- most people were being careful enough to not go charging through the intersection right in front of other traffic. Only a few accidents were reportedly caused by the problem and I suspect that it was more of an excuse than a cause in some cases.
How about a short range RF signal indicator? a cheap analog signal at each intersection; standardized. future cars could use this to provide additional information to the driver. downside is the blackbox in new cars would likely record this so you'd be stuck having the speed and the light used against you in court.
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At intersections that are not brightly lit by street lighting, the LED traffic signals are completely blinding to drivers at night. I actually find myself closing my eyes because of the glare so that my eyes won't have to readjust for the pitch black road on the other side of the light.
I guess it won't be a problem if the sucker is covered by snow and ice.
Just another stupid greenie wacko thing to piss us off and get us killed.
Highs in the 20's F in Nashville, Tennessee in a few days (home of Al Gore). Average high temp: 46F
Eat me, you Global Warming morons.
Out of order? Fuck! Even in the future nothing works! - Dark Helmet (Rick Moranis) "Spaceballs"
So maybe Chicago just bought some shitty fixtures and it doesn't have anything to do with what kind of lamp is burning.
And give you an answer.
I've lived in Chicago my whole life. Long before LED traffic lights were around, I saw an intersection with completely obscured traffic lights on one side. They were filled in with snow. IIRC, it wasn't even snowing at the time, but there was a LOT of snow on the ground and the wind was very strong. Visibility was horrible. The blowing snow covered EVERYTHING, including the incandescent traffic lights. Even with the heat generated by the lights, the snow was still able to completely fill in all of the signals. Given that the lights operate on a cycle, I doubt there was enough heat generated at any given light to melt the snow. Even if there were, there was enough new snow blowing in that it didn't make a difference anyway.
I remember this clearly because I've seen it ONE time in my life. With the right conditions, it can and does happen, just not very often.
Incandescent lamps are absolutely NOT guaranteed to prevent this from occurring.
Something else I remember from that day... the conditions were awful enough that I was very very careful when driving. Green light? Wait 5 seconds or so before proceeding if there is ANY chance whatsoever that a crossing vehicle won't be able to stop. The accident described in this article is because someone wasn't paying attention, period. They are just trying to use the stop lights as a scapegoat to avoid responsibility for vehicular manslaughter caused by their carelessness.
Just change the middle, yellow light back to an incandescent bulb. It should generate enough heat to raise temperature of the housing enough to keep snow from sticking in all but the harshest of weather.
The temperature of the housing only needs to be 1 degree above freezing.
BAH! Just put a clear plastic cover on them! No snow gets in - no snow to melt!
Looks like whoever got modpoints doesn't understand how intersections work, either. I'm glad that SOME of the people who replied to me know how to use an intersection unlike omnichad who should lose his license immediately.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Or have a snow-sensor and kick on a small heating device...
Can't you just have the top of the unit overhanging, no ledges for snow to settle on and a smooth outer surface sloping inwards towards the bottom? I think I've seen the general shape somewhere before - http://images.google.com/images?q=old%20fashioned%20street%20lamp
OK, it's not going to be much use in an ice-storm but then you'd need to vastly over-engineer it for that.