# How many lumens is a street lamp?



## StainlessSteel

How many lumens does your "standard", low pressure sodium street lamp produce?

I have been looking everywhere, but i cant find it.

I KNOW is has to be a HUGE amount, because GE makes a high pressure sodium lamp, for homes, which, at 400 watts, will put out 51,000 lumens.

thanks.

SS


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## BatteryCharger

I would say that they use something very close to a 400 watt HPS. If not that, it's 1000 watts, but I doubt it...


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## Lynx_Arc

From what I have read low pressure sodium puts out approx 180 lumens/watt so a 100 watt bulb would be 1800 lumens, a 400 watt bulb would be around 72,000 lumens using that figure.


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## enLIGHTenment

Most street lights in North America use 250-400 Watt high pressure sodium lamps which produce up to 140 lm/w.


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## MaxaBaker

I have a street light assembly and it's only 150 watts. It's made by GE. I'll take pictures of it when I get home.


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## Zelandeth

35W standard SOX streetlamp. 4800lm (at 100 hours).
250W SON: 26'000lm. 

Those figures should be pretty close provided memory serves correctly. Afraid I don't have data to hand on 55W SOX though.


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## BB

Here is a good general industrial supplies web site: www.grainger.com -- I like it because it has 3,800 pages of everthing from motors to lights to pumps to HVAC stuff. And they list manufacturer's names and list prices (nice to have an idea of what something costs).

If you go to their Grainger's PDF Catalog link and type page number "651" you can see some information on GE low pressure Sodium and Mercury Vapor Lamps.

-Bill


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## MaxaBaker

Here the pics.....









The broken sodium vapor bulb....


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## cobb

WOW, interesting subject. Ive wondered that too as well as traffic lights. I know I have seen a range of traffic lights. White or bluish ones, then the orange like ones. The orange ones always seem brighter, but not sure if its the color or higher wattage bulb. In the shop where I use to work they used white ones over head. 

I have seen those type of fixtures in lowes as well as bulbs, but never looked to see the wattage or any other specs on them. If i remember correctly I think they are more efficient than anything else except led. 

BTW, I was on an led site a few months ago and came across some led lamps to replace the light in a street light. It was over 100 leds in a fixture.


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## LITEmania

for the street lamp of pedestrians, this is enough..


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## yuandrew

Hey, I used to be a streetlight nut myself and here's some info I remember when streetlights.net was in operation.

Well, to tell the wattage of a streetlight and the type of bulb it uses-look on the bottom of the fixture. Normally, you should find a colored lable with a number on it. Multiply that number by 10 and get the color of the lable

Blue-Mercury Vapor (bluish white)
Red- Metal Halide (bright white)
Yellow- High Pressure Sodium Vapor (Yellow-orange)

In my case, the streetlight in front of my house has a yellow lable and a 10 on it so it makes it a 100 watt High pressure sodium.

Note; Streetlights with wattages over 1000 watts will probably have X-1 on the lable instead of 100

MaxaBaker, that bulb is intresting; why does it have 2 arc tubes instead of one? Is one of them a backup?


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## BB

If you look at the Grainger's link above and type in page "649" for High Pressure Sodium Lights... This seems to be a standby tube for extra life:

Entry:
LU150/55/SBY/XL Clear, Standby, Extrailfe, Dual Arc Tube
Average rated hours: 40,000
Lumens Initial: 16,000
Lumens Mean: 14,000
Color Temp: 2,000
CRI: 22
Price (qty 1): $142.70 each

It appears that a single tube version is rated somewhere between 24,000+ to 30,000 hours and is somewhere around $22 to $36 each.

-Bill


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## NewBie

See page 12 LU150

Also see: GE LU150/55/SBY/XL


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## Zelandeth

Yep. the second tube's there for two reasons. Firstly to effecitvely double the lifetime of the lamp, secondly to give the lamp a hot restrike capability.

Never proved to be particularly popular though due to high production costs and the fact that the second arc tube gets in the way, tending to make a mess of optical control - the fact that the tubes have to be positioned off-centre in the outer tube adds to this problem.

A quick trip to Lamptech Link shows that Osram tried out a similar design using a low pressure sodium lamp as far back as 1958. Slightly different idea though in that this was designed to be dimmable, and the two tubes are wired independently of each other rather than being wired in parallel as in the SON lamp shown above. Link


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## degarb

I was hoping to find an 1850's thread, to ask them how many lumens their gas street lights were. But settled upon this 2005 thread.

My curiosity was raised while watching an old movie called "Gaslight". At first, my thinking was that life was dim back then, until I remembered how bright my camping lantern can become. (Apparently, the invention of the gas mantle tripled the lumens, by the 1890s.) Possibly, the electric bulb was a step backwards for brightness and control. Taking over via safety, reliability, ease of use, soot, and cost arguments.

By the way, 2005 people, eventually, there will be LED street lighting, in the next decade. But, bet ya'll already guessed that one.

Now, if someone from 2005 answers me, I just may have to upgrade my cpf account to a paid account.


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## Keitho

Ha! I had a good time, going from a post about the merits of 2018's expected lights over 40,000 lumens to this one.

How long ago was 2005? Here is a top technology news story from that year:

Rupert Murdoch’s News Corp bought myspace.com, a social networking site that allows people to connect to friends, friends of friends, and so on. Though only about two years old, myspace.com has more than 40 million members, who use the site to blog, post descriptions of themselves, and upload music, pictures, and video.


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## broadgage

Here in the UK, most street lights were high pressure sodium until recently. Popular wattages were 70 watts, 100 watts, 150 watts and 250 watts.
Metal halide lamps are used when colour rendering is of more importance.
Incandescent lamps were used up to about 1975 but are virtually unknown now.

Series street lighting was never much used in the UK, more of a USA idea. Arc lamps were used in series, often 8 or 9 or 10 arcs in series on DC mains of 400 volts, 440 volts or 480 volts. Arc lamps "went out with the war" as did most DC supplies though a few survived for longer.


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## degarb

broadgage said:


> Here in the UK, most street lights were high pressure sodium until recently. Popular wattages were 70 watts, 100 watts, 150 watts and 250 watts.
> Metal halide lamps are used when colour rendering is of more importance.
> Incandescent lamps were used up to about 1975 but are virtually unknown now.
> 
> Series street lighting was never much used in the UK, more of a USA idea. Arc lamps were used in series, often 8 or 9 or 10 arcs in series on DC mains of 400 volts, 440 volts or 480 volts. Arc lamps "went out with the war" as did most DC supplies though a few survived for longer.



Interesting. Arc lighting slipped my mind, as the 19th and early 20th century competitor to gas lighting.

My 100 year old Grandfather died in 2002, and the topic of gas lighting never came up--since, I arrogantly assumed it had to be inferior to electric lighting in every way. However, we at least know that it was superior enough to the hurricane lantern, enough, to boost literacy and factory production to around the clock. Made night theatre more practical. I guess, city streets more night friendly.

Only with 8x18650 and a seriously efficient multi die or some diffuse led configuration, could I imagine leds could keep up with a gas camping light. My current guess as to how bright the old gas lighting was is between 300 and 900 lumens (more or less) depending on the cost of gas, supply pressure of the gas company. And, date-pre or post mantle. 

The UK does not have rows of street lights? Around here, one must go to the countryside to escape the street light. Townships, like mine, lack them in the neighborhoods.
I dare not mention the non lighting applications future light poles-since I do believe it won't be good for economic or political democracy. All the ways streetlights can aid in cornering the people and an creating elite class, is a book unto itself. Too obvious are the plethora of possibilities, to bother to mention. With every good new technology application comes 4 negatives, I am now realizing. Not until naivete dies out, are new technologies safe. The problem is that naivete is reborn with each new generation, that it can never die out.


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## broadgage

A single incandescent gas mantle gives a broadly similar output to that of a 60 watt incandescent bulb.
Small or unimportant streets were lit by street lights with a single mantle. Most gas street lights contained multiple mantles. Some are still in use.

All urban areas in the UK have street lighting, but not all rural areas. Most rural places have electricity available, but may not have street lighting.


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## ssanasisredna

Define "Street Lamp". Depending on whether it is a residential street lights, a collector road, a major arterial or highway, not to mention pole height, spacing, etc. they are all different lumen levels.

Probably the most common is around 5000 lumens (at least in LED) used in residential areas. Collectors would be 7500-15000 depending on lanes, spacing, etc. arterials 15,000 - 25,000+, highways/highmast for highways 25,000 - 100,000.

HPS bulbs "can" have high lumens/watt, but their output decays quickly and the optical efficiency is poor because the source is so large and hard to focus.


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## Adam_Clap

depends on the type, but generally between 13000-17000


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## mattheww50

Lynx_Arc said:


> From what I have read low pressure sodium puts out approx 180 lumens/watt so a 100 watt bulb would be 1800 lumens, a 400 watt bulb would be around 72,000 lumens using that figure.



There are very few Low Pressure Sodium Lamps in use in the USA as street lamps. There are some Low Pressure Sodium lamps that exceed 200 lumens per watt. The Color rendition is so limited that it makes them generally unsuitable for street light. Most street lights are in fact High Pressure Sodium, which while not as efficient, the color rendition, as bad as it is with HPS is still light years better than Low Pressure Sodium


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## seniorcare

degarb said:


> I was hoping to find an 1850's thread, to ask them how many lumens their gas street lights were. But settled upon this 2005 thread.
> 
> My curiosity was raised while watching an old movie called "Gaslight". At first, my thinking was that life was dim back then, until I remembered how bright my camping lantern can become. (Apparently, the invention of the gas mantle tripled the lumens, by the 1890s.) Possibly, the electric bulb was a step backwards for brightness and control. Taking over via safety, reliability, ease of use, soot, and cost arguments.
> 
> By the way, 2005 people, eventually, there will be LED street lighting, in the next decade. But, bet ya'll already guessed that one.
> 
> Now, if someone from 2005 answers me, I just may have to upgrade my cpf account to a paid account.



I'm already seeing some of my streetlights being switched over to LED now. The government is trying to save money too.


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