Street light dimming options

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mgookin said:
How do they define "adaptive lighting"?
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If I recall from my Energy class in November. Adaptive lighting or "adaptive compensation" is basically using the fact that the human Eye adapts to the night time light levels. Through the use of lighting controls and step dimming to achieve lower light levels that the human eye will adjust to. Reducing light to areas that are unoccupied or after normal hours of operation. Safety security areas such as ATM's and such are exempted. Basically a Buzzword that mandates less wattage being used.

Anyone more fluent in this area correct me.
 
mgookin said:
Besoeker:

The GM of outdoor controls from one of the big 3 lighting companies came to visit our factory and said there are cities in Europe where there is a dedicated grid for outdoor lighting, and they will switch an entire city on just 2 photocontrols. Do you know what cities he might have been talking about?
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I 'm sorry, I don't.
But then Europe isn't a single homogeneous entity.
Excluding small dependencies, there are over four dozen different countries and forty some of those have populations of over a million.
Total population is over 700 million, about twice that of the USA.
 
Besoeker said:
I 'm sorry, I don't.
But then Europe isn't a single homogeneous entity.
Excluding small dependencies, there are over four dozen different countries and forty some of those have populations of over a million.
Total population is over 700 million, about twice that of the USA.
Click to expand...

We tend to forget that little fact on this side of the pond. Per Wiki, I note that in terms of area Europe and the US are almost the same size, 3.9 million square miles vs 3.7 million square miles, so Europe is about twice as densely populated as the US.
 
Sierrasparky said:
If I recall from my Energy class in November. Adaptive lighting or "adaptive compensation" is basically using the fact that the human Eye adapts to the night time light levels. Through the use of lighting controls and step dimming to achieve lower light levels that the human eye will adjust to. Reducing light to areas that are unoccupied or after normal hours of operation. Safety security areas such as ATM's and such are exempted. Basically a Buzzword that mandates less wattage being used.

Anyone more fluent in this area correct me.
Click to expand...

Interesting.

When a light is on at night, generally you can see between yourself and the light, but you can not see past the light. The problem is more significant with a brighter light relative to the ambient light level of the surrounding area. Golddigger made mention of an example of this when he spoke of the ability to view space from an observatory being impacted by area lighting in the area nearby an observatory. We have the same problem at the observatory on our campus.

Lighting is in one sense relative. During a new moon with an overcast sky in the middle of the night, a light has very high contrast to the surrounding area. Turn that same light on during the daytime (or leave it on) and look right into it and often you can't even tell that it's on at high noon.

And most cameras have auto light levels. Take a picture or video of daybreak and it very well may appear to be a much higher ambient light level than what really exists at the time. DOT cameras and other security/ webcams will show you the same thing.

Our data collection proves that even with the most obstructed atmosphere due to storm clouds at sunrise or sunset that those clouds can never obstruct the light level to or below the prescriptive minimum light levels in ANSI C136.10. The perception is that "the sky is black" but that's a relative thing because the ambient light level is indeed decreasing rapidly as it should as the sun goes over the horizon during a storm.

In India a few years back they attempted to dim lights by the lunar calendar. It's my understanding that it failed because they could not predict the weather. There's understandably a real big difference between the light level reaching Earth from the Sun relative to the light bounced off the moon.
 
Besoeker said:
I 'm sorry, I don't.
But then Europe isn't a single homogeneous entity.
Excluding small dependencies, there are over four dozen different countries and forty some of those have populations of over a million.
Total population is over 700 million, about twice that of the USA.
Click to expand...

Any idea how many outdoor lights you have in Europe?

There's a 2010 University of Pittsburgh Streetlight Study which says there are (were) 131,000,000 street lights and outdoor area lights in the USA. Of course more are added every day.

Links:

http://webcache.googleusercontent.c...comparison-common-a+&cd=1&hl=en&ct=clnk&gl=us

http://www.pitt.edu/news2010/Streetlight-Chart.pdf

Also http://www.pitt.edu/news2010/Streetlight_Report.pdf
 
mgookin said:
Any idea how many outdoor lights you have in Europe?
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I don't and I expect it would have to be looked on a nation by nation basic.
The UK ONS (Office for National Statistics) suggests that there are about 5.6 million street lights in the UK.

A slight, perhaps an interesting and relevant, aside.....
A while back I was on a late flight from Edinburgh to London, about 400 miles, and I had a window seat. At no point on that flight were we out of visual contact of lighting on the ground.
 
mgookin said:
Interesting.

When a light is on at night, generally you can see between yourself and the light, but you can not see past the light. The problem is more significant with a brighter light relative to the ambient light level of the surrounding area. Golddigger made mention of an example of this when he spoke of the ability to view space from an observatory being impacted by area lighting in the area nearby an observatory. We have the same problem at the observatory on our campus.

Lighting is in one sense relative. During a new moon with an overcast sky in the middle of the night, a light has very high contrast to the surrounding area. Turn that same light on during the daytime (or leave it on) and look right into it and often you can't even tell that it's on at high noon.

And most cameras have auto light levels. Take a picture or video of daybreak and it very well may appear to be a much higher ambient light level than what really exists at the time. DOT cameras and other security/ webcams will show you the same thing.

Our data collection proves that even with the most obstructed atmosphere due to storm clouds at sunrise or sunset that those clouds can never obstruct the light level to or below the prescriptive minimum light levels in ANSI C136.10. The perception is that "the sky is black" but that's a relative thing because the ambient light level is indeed decreasing rapidly as it should as the sun goes over the horizon during a storm.

In India a few years back they attempted to dim lights by the lunar calendar. It's my understanding that it failed because they could not predict the weather. There's understandably a real big difference between the light level reaching Earth from the Sun relative to the light bounced off the moon.
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In the very near future we will be seeing parking lot lights with motion sensors and bi levels, highway offramps that are dimmed untill a vehicle is sensed. Outside public areas darkened whith the absence of people. I think that public safety mat get compromised.
 
Sierrasparky said:
In the very near future we will be seeing parking lot lights with motion sensors and bi levels, highway offramps that are dimmed untill a vehicle is sensed. Outside public areas darkened whith the absence of people. I think that public safety mat get compromised.
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It also is probably going to be fine when it works, but how much of it will default to no light at all if something malfunctions??
 
Sierrasparky said:
In the very near future we will be seeing parking lot lights with motion sensors and bi levels, highway offramps that are dimmed untill a vehicle is sensed. Outside public areas darkened whith the absence of people. I think that public safety mat get compromised.
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I'm not very familiar with the trends in parking/highway fixtures, but my impression is that a great many, if not most, are high pressure lamps and not very compatible with this sort of scheme.
 
gadfly56 said:
I'm not very familiar with the trends in parking/highway fixtures, but my impression is that a great many, if not most, are high pressure lamps and not very compatible with this sort of scheme.
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This sort of programmable light output is usually done as part of a conversion to LEDs, and requires a dimmable lamp/fixture.

Tapatalk!
 
GoldDigger said:
This sort of programmable light output is usually done as part of a conversion to LEDs, and requires a dimmable lamp/fixture.

Tapatalk!
Click to expand...

If I were a municipal official, I'd be waiting a few years to see what the real world life for the LED's is. For instance, there are a number of traffic lights along my route of travel that have been converted to LED's a few years ago. Diode failure is spreading like cancer through the arrays. Some of them are about 40% dead. Don't know what the conversion costs were, so I don't know if it was still a net savings, but I wouldn't be happy about it. They were touting something like at least a 10-year life.
 
gadfly56 said:
If I were a municipal official, I'd be waiting a few years to see what the real world life for the LED's is. For instance, there are a number of traffic lights along my route of travel that have been converted to LED's a few years ago. Diode failure is spreading like cancer through the arrays. Some of them are about 40% dead. Don't know what the conversion costs were, so I don't know if it was still a net savings, but I wouldn't be happy about it. They were touting something like at least a 10-year life.
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Something I have been afraid of. At least there is a consortium that is attempting to standardize the LED modules so that replacement is not just like a bulb or ballast.


FYI there are dimmable MH and induction lamps
 
gadfly56 said:
If I were a municipal official, I'd be waiting a few years to see what the real world life for the LED's is. For instance, there are a number of traffic lights along my route of travel that have been converted to LED's a few years ago. Diode failure is spreading like cancer through the arrays. Some of them are about 40% dead. Don't know what the conversion costs were, so I don't know if it was still a net savings, but I wouldn't be happy about it. They were touting something like at least a 10-year life.
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Interesting. How do you know it's diode failure? Are only some of the LEDs in the luminaire dark? In theory, the LEDs do have a tremendous lifetime. But heat is the enemy of electronics and semiconductors, and temperature cycling is the enemy of connection reliability, like solder joints. When commercial residential CFL or LED bulbs fail, it's most often the power supply electronics that fails, not the fluorescent tube or LED itself.
 
Back to the future -- centrally controlled street lighting

Back to the future -- centrally controlled street lighting

It used to be that street lights were connected in series and fed, in loops, by one or more constant current transformers. If you wanted to turn them off at midnight, it was easy, just a few HV switches.

I've been of the opinion, for years, that all advertizing signs at the companies locations should be turned off when the business are closed. Why would I care where a business was if it's closed?
 
LEDfoot said:
Interesting. How do you know it's diode failure? Are only some of the LEDs in the luminaire dark? In theory, the LEDs do have a tremendous lifetime. But heat is the enemy of electronics and semiconductors, and temperature cycling is the enemy of connection reliability, like solder joints. When commercial residential CFL or LED bulbs fail, it's most often the power supply electronics that fails, not the fluorescent tube or LED itself.
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I used "diode failure" to mean "Look, there's a dark spot in the traffic light!" I'm sure there are any number of failure paths. It's typically a contiguous field of dark "pixels", not a radom scattering of freckles.
 
If it is a contiguous field, either it is a series string of diodes to get the voltage up and one or more have failed open or some part of the driver electronics has failed. Since there is no provision for individual control as there would be for a sign, that area of failure is ruled out.
 
fmtjfw said:
I've been of the opinion, for years, that all advertizing signs at the companies locations should be turned off when the business are closed. Why would I care where a business was if it's closed?
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As GD mentions look at the advertising point of view. I don't like to see TV commercials, or printed ads, or listen to radio ads, or have pop up or embedded ads on my computer screen either - but the whole idea is just to have people hear or see your name if you are the advertiser. When thousands or millions hear or see the name, you are likely to get some intended results just because something caught their attention and they maybe remembered your name instead of a competitor.
 
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