Is Induction lamp based streetlighting in UK/Europe/USA/World still being sold?

[ocset]

...or is Induction lamp based streetlighting really taking a back seat now?

[coppercone2]

you mean microwave sulfur lamps?

[ocset]

thanks, but its electrodeless lamps...like flu's but electrodeless...excitation is from external produced magnetic  field at high frequency

[SeanB]

I would guess that LED is going to be used in favour, because of the long lifetime of properly designed units, and the ability to tailor the light output more easily, plus of course the mush lower cost for the same lifetime, and the better efficiency as well. The smaller size as well will help as well for the light and optics.

[bodger]

They're still being sold, however I haven't seen many installations in the UK. Councils here are switching to LED and installing 'smart' central management systems, so they can turn the lights out after midnight to save energy/money.

[Kjelt]

I never saw them used for streetlighting due to the high price.
Like the QL system it was sold for 24/7 billboard lighting like fastfood restaurants and other not easy accesible locations so you want to replace it as little as possible.
The lamp lasts "forever" the ballast was designed for 100000 hours, quite an expensive and exotic application.

Nowadays led would still have only 1/4 of the lifetime and has lumen deprecation so I guess for these exotic applications they are still being sold.

[Ampera]

They're still being sold, however I haven't seen many installations in the UK. Councils here are switching to LED and installing 'smart' central management systems, so they can turn the lights out after midnight to save energy/money.

I still don't get that. If I am outside at 3 in the morning, I damn well want the place to be lit up. Isn't the entire point of urban street lighting to make it harder for criminals to nick someone's stuff in the dark?

The US still clings strongly to our sodium lamps, and I do quite like them from an aesthetic view, but I don't mind the LED takeover. I would prefer it to remain largely on busy streets and highways for light pollution reasons, and to keep sodium lamps in the same old suburbs that I love them in, but LEDs take less power for the effective light they produce, and that's something that's hard to ignore.

[Kjelt]

I would prefer it to remain largely on busy streets and highways for light pollution reasons, and to keep sodium lamps in the same old suburbs that I love them in, but LEDs take less power for the effective light they produce, and that's something that's hard to ignore.

Actually the sodium and hid lamps have a big plus to led and that is that they have long burners which makes it easy with a reflector to produce very nice even lit large area streetlighting.
Compared to leds that need lenses to produce the same, the efficiency is not that much different with sodium winning to white leds due to the humans eye is more perceptive to yellowish light. Sodium can have upto 200Lm/W.
But leds get better and better someday soon probably winning.

[james_s]

That's not really true, streetlighting is something I'm quite knowledgeable about, having had some direct involvement and a couple friends of mine have spent years working in the industry.

The large size of the low pressure sodium arc tube actually makes optical control very challenging. High pressure sodium is quite a bit better in that regard as it is a single slender arc tube rather than the very large U-bend tube. Metal halide is somewhat better, particularly the ceramic type which have very compact arc tubes. An ideal lamp would be a point source of infinitely small diameter, allowing precise optical control by careful design of the reflector and refractor. With a point source you can put all the light exactly where you want it and nowhere else.

Induction lamps are still sold, but mostly only for replacement lamps in existing installations. Technologically induction fluorescent is a dead end, the big name brands have all dumped it years ago as the efficiency is nothing spectacular and the very large surface area makes optical control the worst of all the lamp types I've mentioned.

LED is unequivocally the future of lighting. I think it was at least 3 years ago my friends went to a lighting industry trade show and commented that it was as if nothing else existed. In previous years there was a mix of HID, induction and conventional compact fluorescent sources, this time *everything* being shown was LED. Some types of discharge lamps are already being phased out and the rest will eventually follow. HPS (SON) and metal halide will likely be around for a while for replacement lamps in existing installations but expect consolidation down to just a few low end manufactures.

[Kjelt]

That's not really true, streetlighting is something I'm quite knowledgeable about, having had some direct involvement and a couple friends of mine have spent years working in the industry.
The large size of the low pressure sodium arc tube actually makes optical control very challenging. High pressure sodium is quite a bit better in that regard as it is a single slender arc tube rather than the very large U-bend tube. Metal halide is somewhat better, particularly the ceramic type which have very compact arc tubes. An ideal lamp would be a point source of infinitely small diameter, allowing precise optical control by careful design of the reflector and refractor. With a point source you can put all the light exactly where you want it and nowhere else.

My comment was on high pressure sodium only, never worked myself with low pressure, way before my time .
Their burner resembles the HID burners and comes closer to a point light source than 100's of individual leds you see now. The optics have shifted from reflectors to lenses. I am not an optics specialist, did talk to a lot of them and they said six years ago that this was the main challenge for them for led streetlighting to get a nice even assymmetrical pattern with lenses instead of the reflector they had perfected many years ago.

The tradeshows I recognize. I was in Frankfurt light and building three times and the first time around 2006 I believe it was only conventional lighting, four years latere there were a few LED proposals for street lighting that did not have very good performance.
Green leds were even used and proposed back then yuk.
Again four years later it was a different story and almost only LED proposals, indeed LED took over fast, faster than anticipated by some.

The downside of LED is that any small company can build a led lighting source so you see tons of small companies wanting to pick a part of the pie, with low prices and crap performance/quality.

[Cyberdragon]

[Gyro]

...
Green leds were even used and proposed back then yuk.
...

Green leds would match the eye's peak spectral sensitivity, so would probably achieve high efficiency, but I agree  - Yuk!

I quite like the colour of high pressure Sodium. Low pressure Sodium however, brings back unpleasant childhood memories of lying in the back of a Morris Minor, watching their yellow glow go past while being horribly travel sick! 

[bodger]

I still don't get that. If I am outside at 3 in the morning, I damn well want the place to be lit up. Isn't the entire point of urban street lighting to make it harder for criminals to nick someone's stuff in the dark?

The US still clings strongly to our sodium lamps, and I do quite like them from an aesthetic view, but I don't mind the LED takeover. I would prefer it to remain largely on busy streets and highways for light pollution reasons, and to keep sodium lamps in the same old suburbs that I love them in, but LEDs take less power for the effective light they produce, and that's something that's hard to ignore.

Switching LEDs off after midnight has been limited to mainly rural areas. Turning the street lights off saw a reduction in criminal activity, I presume it makes it harder for the opportunist thief as they'd have a harder time finding whatever it is they want to steal. 

Sodium lamps are certainly more pleasant to the eye, but LEDs are a bit of a no brainer when it comes to energy costs (150W vs 600W+ adds up for thousands of lamps) another positive is they tend to throw light downwards so there is a reduction in light pollution (at least that is how the council advertised the upgrade to LED). You will need thick curtains however if you have a bedroom window near a lamppost. We had LEDs installed 4/5 years ago, wasn't a fan of the bright white light at first, but used to it now.

[tom66]

They're still being sold, however I haven't seen many installations in the UK. Councils here are switching to LED and installing 'smart' central management systems, so they can turn the lights out after midnight to save energy/money.

I still don't get that. If I am outside at 3 in the morning, I damn well want the place to be lit up. Isn't the entire point of urban street lighting to make it harder for criminals to nick someone's stuff in the dark?

Primary reason is pedestrian safety, not theft prevention.    So it's not that useful at midnight when there are very few pedestrians about.

Thieves will steal things lit or not.

[james_s]

I hate the yucky pinkish orange of HPS, it makes all the plants look dead and sprays a lot of glare everywhere but doesn't seem to do a very good job of lighting stuff up. LPS is even worse color but at least it looks kind of cool, it has always been extremely rare in these parts, for some reason it never caught on in the US. The one big advantage in addition to the very high efficiency is that the monochromatic light is easily filtered out for viewing the sky through telescopes and such.

My favorite has always been the old mercury vapor lighting, especially clear lamps that produce that nice soft bluish light almost like moonlight. Grass and foliage absolutely glows under it and everything looks vibrant. It was villainized for the low efficiency and "mercury" in the name despite the fact that MH and HPS lamps also contain mercury, and the efficiency is still higher than the first couple generations of LED streetlights. In most cases around here, the old mercury lights were replaced with HPS of the same wattage, resulting in zero energy savings, only excess light that was not needed. 

[NiHaoMike]

If the main disadvantage of sodium lamps is that they put out pretty much only yellow light, what about supplement them with blue LEDs? How would the overall efficiency compare to the conventional approach of using phosphors to turn some of the blue light into yellow light?

[Kjelt]

Yes great idea, core temperature of the sodium lamps is 800^oC, temperature inside the IP67 fixtures (outdoor lighting remember) can easily go up over 150^oC, LEDs love those, oh wait.....

[CJay]

Dunno, does it flicker though?

[james_s]

There's really no advantage, HPS lamps were high efficiency in their day, but they were not even close to LPS, at least on paper. CMH is very close to HPS efficiency and the modern generation of LEDs has surpassed it.

There's a website that I really like, http://lamptech.co.uk/
It is an amazingly comprehensive collection of electric lamp technology over the years.

[PhilipPeake]

Somewhat off the direct topic, but maybe of general interest.

I grew up in the UK, and back then, (dodging dinosaurs), street lighting was controlled by electro-mechanical time switched. A small synchronous motor drove gearing turning the switch once per 24 hours. settings on the clock face would flip a microswitch on/off at the set times.

The timers for street lights had one extra feature, more gearing for a cam that turned once per year. This cam advanced/retarded the set times to follow daylight at (about) 52 degrees latitude. So long as someone went around and adjusted them after any power outage (rare in those days) they worked fine. Turning on the lights at dusk, and off at daybreak.

Lights were kept on in urban areas mostly because of vehicle lighting laws. If you parked your car on the street, after lighting up time you had to have parking lights on it - basically a red light on the road side/rear and white at the front. People did get tickets for not lighting up their cars. People also had lots of flat batteries on their cars, especially in the winter.

If it was parked on a street with lighting, the requirement didn't apply (well, it did early on, but common sense got the law changed).
Cars parked overnight on the road were much more likely in urban areas.

As someone else mentioned above, lighting generally doesn't reduce crime. Pretty much the reverse. Someone skulking around in the dark with a flashlight is much more obvious that a dimly lit figure lit by street lights.

[CJay]

Somewhat off the direct topic, but maybe of general interest.

I grew up in the UK, and back then, (dodging dinosaurs), street lighting was controlled by electro-mechanical time switched. A small synchronous motor drove gearing turning the switch once per 24 hours. settings on the clock face would flip a microswitch on/off at the set times.

The timers for street lights had one extra feature, more gearing for a cam that turned once per year. This cam advanced/retarded the set times to follow daylight at (about) 52 degrees latitude. So long as someone went around and adjusted them after any power outage (rare in those days) they worked fine. Turning on the lights at dusk, and off at daybreak.

Ah the venerable Venner, I begged a few of those from the guys who refitted the lights in my street with photoelectric cells, the Venner switches were an absolute work of mechanical art and must have been in use for decades

[PhilipPeake]

Somewhat off the direct topic, but maybe of general interest.

I grew up in the UK, and back then, (dodging dinosaurs), street lighting was controlled by electro-mechanical time switched. A small synchronous motor drove gearing turning the switch once per 24 hours. settings on the clock face would flip a microswitch on/off at the set times.

The timers for street lights had one extra feature, more gearing for a cam that turned once per year. This cam advanced/retarded the set times to follow daylight at (about) 52 degrees latitude. So long as someone went around and adjusted them after any power outage (rare in those days) they worked fine. Turning on the lights at dusk, and off at daybreak.

Ah the venerable Venner, I begged a few of those from the guys who refitted the lights in my street with photoelectric cells, the Venner switches were an absolute work of mechanical art and must have been in use for decades

Yes, I think that was the make. I had one, just could never think of a good use for it :-)
But you are right, mechanical works of art.

[Kleinstein]

The blueish light from LEDs and mercury lamps also have 2 extra disadvantages:
1) They distract insects quite a lot - a lot more insects are attracted to the blue light than the yellow HPS.
2) In foggy conditions blue light is scattered more than yellow and can cause poor visibility with too much stray light and dark spots further away from the lamps.

In Germany the yellow light from sodium lamps is also used to mark special points like intersections.

Because of better efficiency LED light will likely take over in many cases.  Reducing the light intensity in less critical times is another nice option.

[james_s]

The control of streetlighting is actually an interesting topic. Now almost everything uses individual photocells on each luminaire to control it. Some installations have a cabinet with a single control for a whole section of lights, this is common along highways and some arterials. Early streetlights were manually controlled by a person who would turn them on each night and off in the morning. Timers have been used but have never been common in North America as far as I know. From the early 1920s up into the 1960s many systems were installed using HV 6.6A series loops which used an electromechanical constant current regulator to power a loop with anywhere from a handful up to hundreds of lights all wired in series. These used special incandescent lamps at first, but later HID, mostly with special ballasts that really are just current transformers for each lamp. One of the big advantages of these series systems is that a large number of lamps could easily be controlled from one location, whether that be a manual switch or an expensive vacuum tube photocell.

As of about 5 years ago Los Angeles still had around 40,000 series streetlights, a lot of them HID but still thousands of incandescent post-top "acorn" lights and some teardrop and gumball types on poles or spanwires. Several other large cities across the US still have large numbers of series lights too, mostly HID. A few years ago the last company making the series incandescent lamps decided to phase them out, one of the products I can lay claim to developing is a transformer used to retrofit mains voltage lights to these old series loops. For a long time I was not aware of any series streetlighting anywhere else in the world however we did discover similar systems being used in Italy. Airport runway lighting is also almost exclusively 6.6A series, I suspect it will remain in that application for a long time.

There were a few other interesting control schemes, one was a cascading system of contactors where a central switch would turn on one group of lights, which would also turn on a contactor at the end of that line which would turn on another group of lights fed from another source and so on. Like the series systems it was a method of controlling lights spread over a long distance while avoiding the voltage drop issues you would have if you tried to run mains voltage to lights along a 20 mile stretch of road all fed from one source.

[Kjelt]

Many cities are going to smart city streetlighting where the "controllers" can remotely control the lights with schedules but also turn entire cityblocks on in case of an emergency. The lamps can be remotely controlled and signal themselves when something is out of order eg a light is not performing to specifications or other problems. Annual energycosts can be monitored in case of running over budget low cost schedules or lighting patterns can be selected, eg one of two lights on etc. Etc.
Endless possibilities.

https://www.currentbyge.com/ideas/intelligent-cities
http://www.lighting.philips.com/main/systems/lighting-systems/citytouch

[PointyOintment]

Sodium lamps are certainly more pleasant to the eye, but LEDs are a bit of a no brainer when it comes to energy costs (150W vs 600W+ adds up for thousands of lamps) another positive is they tend to throw light downwards so there is a reduction in light pollution (at least that is how the council advertised the upgrade to LED). You will need thick curtains however if you have a bedroom window near a lamppost. We had LEDs installed 4/5 years ago, wasn't a fan of the bright white light at first, but used to it now.

I had the opposite experience. My street used to have LPS and was upgraded to LED about a year and a half ago. The lamp that's visible from my bedroom is about one lot along and on the other side of the street. Also, the top of my bedroom window is at nearly the same elevation as the lamp head, due to the house being higher than the street.

The old lamp, with its hemispherical diffuser, used to shine in my bedroom window quite brightly at night, casting a bright projection of the window on the wall, which would then by scattering illuminate the whole room dimly. When I was a little kid, my parents had to install a blackout blind so I could sleep. (When we renovated, it was replaced by a fancy wooden top-down/bottom-up blind, which doesn't block as much light, but I'm no longer as sensitive to light when sleeping.)

The new LED lamp emits much less light sideways, and while you can still see a projection on the wall, it's very dim and it doesn't perceptibly illuminate the room. When it was installed, I was surprised to be in pretty much total darkness the first time I turned off the room lighting at night with the blind open—the old LPS lamp gave enough light to see my way around the room by!

Somewhat off the direct topic, but maybe of general interest.

I grew up in the UK, and back then, (dodging dinosaurs), street lighting was controlled by electro-mechanical time switched. A small synchronous motor drove gearing turning the switch once per 24 hours. settings on the clock face would flip a microswitch on/off at the set times.

The timers for street lights had one extra feature, more gearing for a cam that turned once per year. This cam advanced/retarded the set times to follow daylight at (about) 52 degrees latitude. So long as someone went around and adjusted them after any power outage (rare in those days) they worked fine. Turning on the lights at dusk, and off at daybreak.

Ah the venerable Venner, I begged a few of those from the guys who refitted the lights in my street with photoelectric cells, the Venner switches were an absolute work of mechanical art and must have been in use for decades

Yes, I think that was the make. I had one, just could never think of a good use for it :-)
But you are right, mechanical works of art.

Big Clive did a video on a Sangamo brand streetlamp timer, for anybody who wants to see what one of those timers looks like inside:

[Cyberdragon]

Many cities are going to smart city streetlighting where the "controllers" can remotely control the lights with schedules but also turn entire cityblocks on in case of an emergency. The lamps can be remotely controlled and signal themselves when something is out of order eg a light is not performing to specifications or other problems. Annual energycosts can be monitored in case of running over budget low cost schedules or lighting patterns can be selected, eg one of two lights on etc. Etc.
Endless possibilities.

https://www.currentbyge.com/ideas/intelligent-cities
http://www.lighting.philips.com/main/systems/lighting-systems/citytouch

Pfft, "smart". As predicated by that word being totally opposite...hack fodder! The only reason it's not widespread is because these controllers are somewhat rare and people are far more interested in the traffic signals than the road illumination.

How do series string lights avoid going out like old fairy lights?

[Kjelt]

Pfft, "smart". As predicated by that word being totally opposite...hack fodder! The only reason it's not widespread is because these controllers are somewhat rare and people are far more interested in the traffic signals than the road illumination.

Don;t understand what this has to do with the subject. Ofcourse as with any internet connected facility it is a potential target for hackers.
The "smart" part is that in case of an emergency for instance or a criminal at large entire city blocks can be put to full illumination as a simple example.
Or to save energy put at dimming levels in case there is little trafic for instance on christmass nights or other occasions people stay at home.

How do series string lights avoid going out like old fairy lights? 

What do you mean with strings? They can be individually controlled have their own IP or wireless connection and mains connection.

[Cyberdragon]

You seemed to confuse the bottom with the top. I mean the older style incandescants/discharge.

[dmills]

Series string bulbs are designed so that tension in the filament holds a contact gap open, when the filament snaps, the contact closes shorting out the failed lamp and leaving the series chain functional (The constant current driver just has a lower terminal voltage).

You can see something similar in the old school series Christmas light sets, except they were usually directly across the mains so as more lamps failed the rest of the chain got brighter until the one bulb (usually IIRC with a white cap) that did not have the shorting switch failed and shut the whole thing down.

Regards, Dan.

[PointyOintment]

How do series string lights avoid going out like old fairy lights? 

What do you mean with strings? They can be individually controlled have their own IP or wireless connection and mains connection.

Referring to those described in james_s's post. My understanding (and it's a bit shaky because I'd never heard of them in street lighting before this thread) is that they're not wired directly in series, but instead there's one wire, carrying 6.6 amps, with several current transformers wrapped around it, one for each bulb. When one of the bulbs fails, that current transformer just stops drawing power, and the power supply can reduce its voltage a little bit to maintain the 6.6 A current.

From the early 1920s up into the 1960s many systems were installed using HV 6.6A series loops which used an electromechanical constant current regulator to power a loop with anywhere from a handful up to hundreds of lights all wired in series. These used special incandescent lamps at first, but later HID, mostly with special ballasts that really are just current transformers for each lamp.

I assume "special incandescent lamps" means

Series string bulbs are designed so that tension in the filament holds a contact gap open, when the filament snaps, the contact closes shorting out the failed lamp and leaving the series chain functional (The constant current driver just has a lower terminal voltage).

[bodger]

Pfft, "smart". As predicated by that word being totally opposite...

They're pretty smart the new systems, I was speaking some installers a few years back; They were installing outposts that control the lamps replacing the old light sensor fitted on top of every ballast (I think that's the technical term). Anyway these outpost can individually be programmed, they can report back things like when a lamp is blown, power factor, power usage, brown outs, etc. I think what the council liked is they have power meters in each individual outpost, which means they no longer have to use the energy supplier's reading and pay for power lost in the wire getting to the lamp.

[Cyberdragon]

How do series string lights avoid going out like old fairy lights? 

What do you mean with strings? They can be individually controlled have their own IP or wireless connection and mains connection.

Referring to those described in james_s's post. My understanding (and it's a bit shaky because I'd never heard of them in street lighting before this thread) is that they're not wired directly in series, but instead there's one wire, carrying 6.6 amps, with several current transformers wrapped around it, one for each bulb. When one of the bulbs fails, that current transformer just stops drawing power, and the power supply can reduce its voltage a little bit to maintain the 6.6 A current.

From the early 1920s up into the 1960s many systems were installed using HV 6.6A series loops which used an electromechanical constant current regulator to power a loop with anywhere from a handful up to hundreds of lights all wired in series. These used special incandescent lamps at first, but later HID, mostly with special ballasts that really are just current transformers for each lamp.

I assume "special incandescent lamps" means

Series string bulbs are designed so that tension in the filament holds a contact gap open, when the filament snaps, the contact closes shorting out the failed lamp and leaving the series chain functional (The constant current driver just has a lower terminal voltage).

I assume the contact is on the filament holder somewhere near the bottom? (This is actually from a current store listing )

[Kjelt]

Referring to those described in james_s's post. My understanding (and it's a bit shaky because I'd never heard of them in street lighting before this thread) is that they're not wired directly in series, but instead there's one wire, carrying 6.6 amps, with several current transformers wrapped around it, one for each bulb. When one of the bulbs fails, that current transformer just stops drawing power, and the power supply can reduce its voltage a little bit to maintain the 6.6 A current.

We don't have those in our country but I believe I once saw this in Italy being used.

[PointyOintment]

Referring to those described in james_s's post. My understanding (and it's a bit shaky because I'd never heard of them in street lighting before this thread) is that they're not wired directly in series, but instead there's one wire, carrying 6.6 amps, with several current transformers wrapped around it, one for each bulb. When one of the bulbs fails, that current transformer just stops drawing power, and the power supply can reduce its voltage a little bit to maintain the 6.6 A current.

We don't have those in our country but I believe I once saw this in Italy being used.

That would make sense, given that

For a long time I was not aware of any series streetlighting anywhere else in the world however we did discover similar systems being used in Italy.

[james_s]

Series string bulbs are designed so that tension in the filament holds a contact gap open, when the filament snaps, the contact closes shorting out the failed lamp and leaving the series chain functional (The constant current driver just has a lower terminal voltage).

You can see something similar in the old school series Christmas light sets, except they were usually directly across the mains so as more lamps failed the rest of the chain got brighter until the one bulb (usually IIRC with a white cap) that did not have the shorting switch failed and shut the whole thing down.

Regards, Dan.

No, that's not how the Christmas lights work, there is no spring tension. The shunt is coating with an insulating oxide and acts as an open circuit. When the filament opens, the full mains voltage appears across the shunt and flashes through the oxide completing the circuit.

Incandescent series streetlights indeed wire the lamps directly in series but the bulbs themselves don't have shunts. Instead there is a shorting disc between the prongs where the special lampholder plugs into a socket. The way it is set up, you can pull the lampholder out of the socket and the contacts in the socket spring closed to complete the circuit, and when you plug it in, if the lamp itself goes open the shorting disc will flash through its mica insulator and also complete the circuit. The lamps are special in that they are rated for 6.6 Amps rather than being rated for a specific voltage. The actual voltages they run at are oddball values that depend on the wattage, typically anywhere from 12V to around 90V. The lamps are printed only with a rating in lumens though, 6000L is one of the more common sizes.

When HID lamps are used on these same series circuits, each lamp has an isolation current transformer. They did make special mercury vapor lamps intended for direct operation on special series circuits but they had some serious drawbacks. Due to the fact that a mercury lamp won't restrike until it cools off, a momentary power interruption would activate the shunts in the whole string of lamps, requiring them to all need replacing.

[Cyberdragon]

There's a website that seems to have alot of vintage electrical info.

http://www.kbrhorse.net/streetlights/understanding_shunts02.html

[james_s]

That site has some great info, if you back up one level there is a picture of a series lamp, they are easily identifiable due to the unusually short V shaped filament. The picture posted earlier in this thread is actually a 120V lamp with a C filament.