A change that took place quietly -- LED traffic signals

[eppur_se_muova]

Why are they replacing all of the traffic lights in my town?

The new traffic lights you are seeing are made out of arrays of light emitting diodes (LEDs). These are tiny, purely electronic lights that are extremely energy efficient and have a very long life. Each LED is about the size of a pencil eraser, so hundreds of them are used together in an array. The LEDs are replacing the old-style incandescent halogen bulbs rated at between 50 and 150 watts. Most cities in the United States are in the process of replacing their incandescent traffic lights with LED units because of three big advantages:

LEDs are brighter. The LED arrays fill the entire "hole" and have equal brightness across the entire surface, making them brighter overall.

LED bulbs last for years, while halogen bulbs last for months. Replacing bulbs costs money for the trucks and people who do the work, and it also ties up traffic. Increasing the replacement interval can save a city big dollars.

LED bulbs save a lot of energy.

The energy savings of LED lights can be huge. Assume that a traffic light uses 100-watt bulbs today. The light is on 24 hours a day, so it uses 2.4 kilowatt-hours per day. If you assume power costs 8 cents per kilowatt-hour, it means that one traffic signal costs about 20 cents a day to operate, or about $73 per year. There are perhaps eight signals per intersection, so that's almost $600 per year in power per intersection. A big city has thousands of intersections, so it can cost millions of dollars just to power all the traffic lights. LED bulbs might consume 15 or 20 watts instead of 100, so the power consumption drops by a factor of five or six. A city can easily save a million dollars a year by replacing all of the bulbs with LED units. These low-energy bulbs also open the possibility of using solar panels instead of running an electrical line, which saves money in remote areas.
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more: http://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/question178.htm





Solar Modules Used For Traffic Lighting

The company manufactures and supplies excellent range of traffic lighting solar modules. These solar LED lights are widely used on roads to prevent the possibilities of accidents. Our solar powered traffic lights are perfect for road safety and traffic control applications, which also helps in reducing electricity bill. There is no trenching, wiring or electrical work required in these traffic lights. We supply all types of solar products for road light, traffic signal light and road ground light.

Solar powered traffic lights can also be used in temporary settings, where a traffic signal is only needed for a set period of time. These temporary solar traffic signals can be supported on a post, trailer mounted, secured momentarily and placed quickly at traffic intersections.

Solar traffic lights are fitted with the latest technology in electronics. These are based on photovoltaic or PV for short. A solar panel located on the top of the pole converts sunlight into electrical power. A solar charger regulates the voltage coming out of the solar panel. The regulated power obtained is used to charge a battery. Lighting is produced by arrays of extra bright LEDs (Light Emitting Diodes) that are much brighter than bulbs. LEDs last for years and are very energy efficient. LEDs are small, but they can produce a significant amount of light. If solar lighting is progressing very fast, it is mainly due to LED technology.

On simple and stand-alone traffic lights a timer controls the lighting sequence at fixed intervals. Radar sensors can also activate them. Sets of traffic lights are usually radio linked together, insuring wire-less communication between the lights. A master traffic light connected to a computerized controller/sequencer synchronizes and controls the slave unit
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more: http://microsunsolar.tradeget.com/F17525/solar_modules_used_for_traffic_lighting.html



ON EDIT: Posted after I saw an LED turn lane sign the other day. Bright as neon -- you couldn't miss it. It would be a huge improvement even if it didn't save energy or last longer!

[ixion]

1. I've been switching over to LED

very happy with the performance. Decent light, and they last for years.

[HowHasItComeToThis]

7. PROGRESS HAPPENS

[BrklynLiberal]

2. I read an article a while back about how many millions of dollars NYC was saving by

switching to the LED traffic lights.
I have seen the solar panels of many street lights...and along the highways for emergency phones.

This is good news...

Now, if I could only gt some solar panels for my house..

[donco6]

3. We switched all of our buses years ago. n/t

[kestrel91316]

4. I LOVE our new LED traffic signals in Los Angeles. Especially the pedestrian

signals, which have added a countdown-to-red function.

[Nederland]

5. A beautiful example

...of what happens when you can make something cheaper than existing technology. You don't need big plans or complicated legislation to promote the transition--it just happens all by itself.

Cost is the key. Make a competitively priced car that is cheaper to run than a gasoline car, and people will abandon their fossil fuel time bombs in droves.

[VWolf]

6. What I'd like to know is

how long they need to operate before they cover the costs of switching over. I know they cost more to manufacture than incandescents.

I'm guessing no more than a year or so. Anyone know?

[ixion]

8. I don't have exact statistics in front of me, however

I have been using LED for a few years now... since 2006. I an LED light in the bathroom that's been running continuously since 2007. It's still chugging along.

Same goes for an LED I have plugged into my server.

I would say: Pay for themselves in a year, start saving money for several years thereafter.

[Mopar151]

9. Very dependent on the labor cost of re-lamping

I'm thinkin' save 1 replacement cycle, you just bought the bulbs - ongoing energy savings is gravy.

[happyslug]

15. The real saving is the cost of REPLACING the light

Getting a person with a truck with a bucket to change the bulb is expensive. If an LED needs replaced just 1/2 the time of an incandescent, it has paid for itself in terms of labor and truck. The Light bulb has always been a minor cost, the main cost is the LABOR to do the change. Thus in my area, when one bulb goes out, whoever does the change, change ALL them just to save the money in changing them one at time when they bulb out.

Please note, I mention just twice the life of an incandescent light, LED last 10 times the life of an incandescent light, but the main savings is first and first most in labor cost in reduction of cost of changing the bulb. The electric savings is minor compared to the labor costs.

[Fumesucker]

10. This is the neatest LED light I've seen.. 500 watts peak power..

http://www.candlepowerforums.com/vb/showthread.php?t=221261





Car halogen headlight on high beam..



500 Watt LED light with same settings on the camera..

[eppur_se_muova]

11. Well, that should blind plenty of drivers in oncoming traffic!

That's the whole point of "high performance" headlights, right?

[Fumesucker]

13. It's actually a handlight..

Funny you should say that though, I was reading on an electric bike forum the other day and a Quebecois was telling how he got pulled over by the popo on his e-bike because they though that he was an airplane approaching with its landing lights on from about two miles away.. :)

He had some new LED lights on his e-bike..

They axed him not to use them on the road any more.

I have a flashing red LED tail light on my bike that's almost painful to look at it's so bright.

[phantom power]

14. Are those the Cree LEDs?

[conscious evolution]

20. I have a friend in a wheelchair

who uses them.
Says it saved him a lot of money in batterys in addition to having better visibilty for approaching cars to be able to see him.
I also know cavers who swear by them.They say their headlamps last for months now instead of hours.

[happyslug]

19. Nite Rider has a 1200 Lumen light

http://www.niterider.com/prod_pro1200.shtml

Please note Watt is a measurement of electrical Power NOT light, Lumens is the Metric measurement of Light (Candlepower is the English Light Measurement).

[HillbillyBob]

12. LEDs are making progress and are getting better

LEDs are making progress and are getting better as research allows and brighter (shop carefully some are shoddy..it is hard to tell which ones) we have been buying ours at Sams Club(member ship is one of the very few benefits partner gets from his job) I saw some at Home Depot in the same wattages as the ones at Sam's, but at a much higher price, but they do look like better quality.

[happyslug]

16. Yes, about 20 years ago the only LED were tail lights on bicycles

Then about 10-15 years ago large trucks and trailers tail-lights started to go LED. Cars and light trucks (including SUVs) started to have them much later (5-10 years ago). About five years ago, bicycle headlights started to go LED. About two years ago the Federal Government finally passed regulations as to headlights on motor vehicle, have NOT seen any LED automotive headlights, but the regulations are in place (The regulations said that if one LED bulb goes bad ALL of the LED lights must go out, the rationale for this is to encourage people to replace LED headlights whenever any one of the LEDs go bad, instead of just keeping the headlight in use for most of the LEDs would still be working).

[joshcryer]

17. Handheld flashlights, especially the charagable variety, have also benefited from LEDs.

I got a $30 Maglight I found on the ground in the snow, it's amazing. I feel bad for the guy who lost it! :)

[Canuckistanian]

18. I once won a prize for suggesting an incadescent to LED light replacement

It saved the company I was working at several hundreds of dollars a year.

What was it? This:




LED Exit signs.

[TreasonousBastard]

21. Before you all jump up and down, we have them here and...

yes they are nice and evenly bright and yes they don't have to be replaced as often as the halogens.

But, the first problem you notice is that they aren't hot, so the snow that blows on them isn't melted off. Not a problem in Miami or LA, but a problem here.

Then, you notice these little holes where individual LEDs burned out. That's when the highway department starts dealing with its budget and deciding how many holes before the light is no longer effective and you have to replace it muuch sooner than you expected.

[trof]

22. Forwarded to our city manager. Thanks.