Wow that's quite cool, the LED is behind a frosted diffuser, and then that is bounced downwards off a reflector? Must be very low glare compared to the bare LEDs rubbish!

Edit: Nevermind... I see in the day picture it's still bare LEDs behind a lens

Wow so cool
Looks like a movie scene

Ewww. They are replacing 250w HPS here with those same lights. The glare you get when approaching them from the side is insane.

Lumex, by looking at the photo the "glare stars" that the camera makes makes he glare from both lamps appear the same
Many of us lighting enthusiasts like to look up at the street lights at night which makes glare almost impossible to avoid, but the average person would look in front of them rather than the lighting, when they do that the chance to avoid glare becomes higher. Behind either of-the streetlights is lit up the same as well as the street...
With all that said I agree with you that replacing 250W HPS with LED is rather gross

Thats actually pretty smart, but orange phosphored LEDs would've been much better then amber phosphored LEDs.

Its a step in the right direction!. To bad they didn't just make an all glass LED replacement lamp that goes in the existing fixture. The LED would just be one single large orange filament mounted to the same support frame as an arctube would and the lens optics of the fixture would work the same if the LED filament was the same shape and size as an HPS tube

True, but what would be even better if they could math the HPS color and have that 60Hz flicker they all have

The HPS color, while neat, is not efficient.

The HPS color, while neat, is not efficient.

Are you sure about that?

Btw, DEL is LED in French. And I'll try to find more info on these new heads. Personally I hate the white LEDs but this is very pleasing.

I second that, I can't stand white LEDs that have a lot of blue, but warm white all the way to orange is great and reduces glare for me

Are you sure about that?

Technically, he's right, as whilst HPS are very efficient, the colour of light they put out does have a very low scotopic ratio. (The eye picks up blue light relatively more in low light levels). If two lights have the same Lm/W, one 2000K and one 4000K, the 4000K will be more efficient as far as low light levels are concerned.

I don't care if he's technically right or not. I don't like LED street lamps and never will, sorry.

I was just adressing the statement about efficiency of light colours, which applies not only to LEDs (I don't like the vast majority of them either). For example you can get MH bulbs to retrofit HPS on the same ballast which may seem less efficient, but when you take into acount the increase in CCT it's actually pretty comparable.

I was just adressing the statement about efficiency of light colours, which applies not only to LEDs. For example you can get MH bulbs to retrofit HPS on the same ballast which may seem less efficient, but when you take into acount the increase in CCT it's actually pretty comparable.

You may be right, I have no doubt that you are, but what I am complaining about is the fact that I no longer have a choice, LED is taking over, whether people want it or not.

For my personal domestic lighting, while I technically do have a choice, I am no longer able to buy anything else but LED. Maybe a few CFL's and halogens, but no incandescents. If I'm paying the bill, what business is it of anyone else what lamps I use..?

For street lighting, again there is no choice. The councils or whatever authority it is just install the things, with no consultation whatever with the electorate who voted them in. This just annoys me. If a poll were to be taken and the result was that the majority of people in a given area preferred LED street lighting, then I would accept it. I wouldn't like it, but I would accept it. What I do not accept is being told I will have LED lighting whether I want it or not.

MissRiaElaine is right I was poking around the internet and anything not led was almost non existent you could still buy some hid and fluorecent lamps but fixtures for them forget it.

MissRiaElaine is right I was poking around the internet and anything not led was almost non existent you could still buy some hid and fluorecent lamps but fixtures for them forget it.

I know an electrician who has to resort to eBay for anything not LED. None of his local wholesalers stock anything else..!

Hm, well I'm sorry that's the case for you, there's still quite a lot of places to get incans where I am, and of course, there's online.

True, there is not enough consulation done, but that is the case with many things sadly, in the end it usually just comes down to saving money, and they really don't seem to care what people think, as there's been several surveys done that find that people overwhelmingly prefer lower colour temperature light, yet still it seem the majority of LEDs installed are 4000K.

Wow 71W LED is actually comparable to these 250W HPS! 70W 3000K AEL LEDs were installed here to replace 250W HPS and they're substantially dimmer. They're rated 7000-and-change lumens, about as many lumens as a 175W MV lamp but they light the road as well as a 150W HPS.

The topic of scotopic/photopic as well as mesopic/circadian sensibility is a vague and inaccurate area for many so-called experts. Taking S/P ratios and applying them to the colors provided by different lighting systems is a gross misdirection.

Yes, the lumen, defined only according to the response of cones, has been established as an inadequate measure of visibility at low light levels. But what are these levels?

I've done many tests. I have walked in the light of the Full Moon and I can easily state that color is still perceptible, at least to me. This would probably be where mesopic vision starts and anything above that light, I would place in the photopic region. At the very brightest, the lux values on the ground with a FULL moon above a 60° height is 0.25 lux. The very worst lumen depreciated and dirty 70 and 100 watt HPS street lights I have measured around 1 lux minimum (it's less than 1 lux some distance from the nadir). This is 4 times the light of a FULL moon overhead and well into photopic.

I also have a country place where I can indeed experience scotopic vision. With a moon up in the sky, objects viewed in peripheral areas of the eye will be sensed in a mesopic process. As the distance from the fovea increases, vision shifts increasingly toward scotopic; acuity becomes poor and spectral sensitivity is shifted to bluer wavelengths with color finally becoming absent; the balance moves in the direction of proper scotopic vision as the light level further declines. Anything more than a crescent moon in the sky prevents full scotopic vision. In the absence of any moon or artificial lighting, vision is scotopic, no color is discerned - unless one looks at the brightest stars .

With just the stars in the sky and perhaps the milky way in average country skies, scotopic vision allows one to see the ground in about ten minutes of dark adaptation. For very dark skies it may take up to 20 minutes to see the ground. With heavily overcast skies in the dark-sky sites, you need a half hour to see the ground. But dark adaptation continues after 1 hour in total darkness giving additional gains in sensitivity. Under favorable conditions, our rods can be triggered by individual photons!

Unfortunately, practically no person todayhas a dark enough place or is adequately patient enough to experience the full capabilities of their dark-adaptation or scotopic vision.

Wow 71W LED is actually comparable to these 250W HPS! 70W 3000K AEL LEDs were installed here to replace 250W HPS and they're substantially dimmer. They're rated 7000-and-change lumens, about as many lumens as a 175W MV lamp but they light the road as well as a 150W HPS.

The camera might be exagerating it a little though, I have had that happen when I try to take pictures of two different light sources at once. They installed some of those Devolves around here to replace 250w HPS and they are more of a 150w replacement. Not sure what the wattage is though.

I have experienced scotopic vision, outside...in a dark place away from city lights....doing astronomy, but these days, even "here at the end of the Earth" finding a truely dark place is difficult. The lights of Hobart and even smaller towns can be seen in even in clear air when the city or town is hidden behind a hill...with cloud the orangish glow from thousands of HPS and other lamps is very obvious, even from up to 80Km away.

We still have HPS on our main roads, but I am expecting semiconductor lighting to appear within the next few years.


Interesting Ria that Local Government is as arrogant as f**k over there too, they are intolerable here....but I suppose the "sludge" of society has to end up somewhere...but the average person is tolerating it less and less.


Quote from Lighting Guy 1994..."To bad they didn't just make an all glass LED replacement lamp that goes in the existing fixture"

The main reason they don't do this is because they simply can't get enough heat away from the active devices, (Light emitting diode arrays). In low powered domestic applications in the 3-10w range, Helium Gas with its high atomic velocity is enough the just get enough heat away, but the long term reliability is unproven. Whereas at power levels from 5w and up...nothing beats a large block of alunimium and some tin oxide paste to get the heat out the back of an active semiconductor device. In this case the die-cast body of the luminaire is both the heatsink and the optices of the unit, so the thermal requirements and polar radiation distribution of the active devices dominate the design.

The problem with satisfying 7.5 billion people on this planet is an impossibility. So I can live with and accept plenty of compromise; I'm less annoyed in this manner. The need to profiteer by everyone involved in any authoritative position is the one I struggle with.

You are not suggesting c0***ption in positions of authority and "responsibility"....surely not in "1st" world countries like Australia and Canada...sic!!

There is a very easy way to fix it though...chuck out all the lawyers, real estate agents, union officials, accountants, pencil pushers, bean counters, ex CEO's and all other types of parasitic occupations from these positions and replace them with scientists, tradesmen, mothers and engineers....then the problem will largely disappear as if by magic!

Is it just me, or is this getting a little heated?

Easy to fix? No offense intended, but sadly, you and I know that that's a pipe-dream. This change can only come about with some sort of bloody revolution..but then again, apartheid was dissolved relatively blood-free in S.A., so I have hope. The capitalist system that these commonwealth countries adore so dearly has to end for the types of changes you mention. Forget about the USA.

You are not suggesting c0***ption in positions of authority and "responsibility"....surely not in "1st" world countries like Australia and Canada...sic!!

There is a very easy way to fix it though...chuck out all the lawyers, real estate agents, union officials, accountants, pencil pushers, bean counters, ex CEO's and all other types of parasitic occupations from these positions and replace them with scientists, tradesmen, mothers and engineers....then the problem will largely disappear as if by magic!

Until those people become corrupted aswell. It is a cycle it seems. Perhaps I'm looking too deeply at this statement, but at the same time that thought has boiled in the back of my mind for a long time, the fact that people are just people and eventually they can and in certain positions will become corrupted.

Easy to fix? No offense intended, but sadly, you and I know that that's a pipe-dream. This change can only come about with some sort of bloody revolution..but then again, apartheid was dissolved relatively blood-free in S.A., so I have hope. The capitalist system that these commonwealth countries adore so dearly has to end for the types of changes you mention. Forget about the USA.

The solution might be some thing simple, something that hasn't been though of... what if us, the lighting collectors, become the decision makers?

The solution might be some thing simple, something that hasn't been though of... what if us, the lighting collectors, become the decision makers?

I don't see that making much of a difference. It'd likely still lead to conflicts aswell as people disliking changes or the lack of change depending on the situation.

I don't see that making much of a difference. It'd likely still lead to conflicts aswell as people disliking changes or the lack of change depending on the situation.

If lighting enthusiasts were in charge of streetlighting, there might not actually be that much change in the first place. (I, for one, would want to replace everything with CMH, but realistically I would keep HPS)

I don't care if he's technically right or not. I don't like LED street lamps and never will, sorry.

You don't have to like them, but you do have to put up with them because they are here to stay and replace the inefficient HPS, LPS, MH, and MV.

You don't have to like them, but you do have to put up with them because they are here to stay and replace the inefficient HPS, LPS, MH, and MV.

Oh come on, HPS and MH aren't that inefficient. And besides, LED has yet to surpass LPS in terms of raw LPW.

You don't have to like them, but you do have to put up with them because they are here to stay

I am gonna have to agree with this, like LED or not you're just gonna have to learn to live with it...
Its just like when HPS replaced MV, I didn't like it at all but just learn to live with it.
Eventually something 'new and better' will come along that will replace LED (won't be within my lifetime) and people then will probably say the same stuff about whatever the new light-thing is.

Ria i don't know why you are complaining about no say about led street lights being installed where you are, as long as there has been street light people never got a choice or say on what type of light it would be nor will we ever so it is not something that is forced upon us.
BTW is is not the elected members of your council allegedly forcing these led street lights upon you it is the town planning department which are not an elected bunch of people.
People should stop looking up at streetlights directly or taking pictures of led street lights standing directly under them an then trying to say they are glare bombs, I know plenty of hps and metal halide street light that glare if you look straight into them.
The picture taken here is a reasonable like for like pic done at the right angle and distance are shows a realistic shot and is not at all bad.

I agree, this is a reasonable comparison and a nice picture that shows that you can indeed replace ~300 W (system) HPS streetlights with (the right) 71 W LED systems. Given the large difference in consumed power between the different systems (around a factor x4 here!), this is proof that LED luminaires can be made to be significantly more efficient/effective than HIDs in their applications (including streetlights here), it's only a matter of using the right system with the proper design. Affirming the contrary (i.e. many comments above) is only evidence of the commentator's ignorance in the matter...

By the way, in reply to Lumex's comment that LEDs have yet to surpass SOX lamps in terms of source efficacy, this has already happened in the lab in 2011 (Cree, 231 lm/W), and commercial 200 lm/W LED devices were first released on the market in 2014, also by Cree. Now, in the lab LEDs exceed 300 lm/W, so fact is that SOX lamps are already far behind, especially when the optical control of the emitted light is factored in. It's no wonder that Philips has decided to end the production of its SOX lamps for next year.

These are the cold hard facts, and you can whine all you want LEDs are here to stay, our civilization is not going back to HPS, like we did not go back to mercury vapor after HPS was introduced. Now, as a lighting enthusiast there is nothing I enjoy more than watching discharge lamps running up, and I feel that electrical discharges have the same special "something" that combustion fire has, and these means of light production are certainly more, let's say "organic", than that from electron-hole recombination in semi-conductor juntions - that's why I use several HID luminaires at home. Nevertheless, technology keeps on changing, there are always people out there willing to push the envelope and wanting to break new grounds; the vast majority of people forming our civilization actually welcomes it, and while there's always a loud minority who like to waste its time complaining about it (we know who you are), repeated (and annoying) tantrums won't stop the tides of progress.
All births and transitions are messy affairs, there are no exceptions to that. Early automobiles were less reliable, more noisy, dirtier than horse carts. Early mercury vapor lamps had a very poor light color. Early HPS lamps were shorter lived and could not be run at all positions, etc... Early LEDs have reliability issues and poorly designed systems are glary. But like with anything else before, wrinkles will eventually be ironed out. Expecting anything else is only unrealistic.

Eventually something 'new and better' will come along that will replace LED (won't be within my lifetime) and people then will probably say the same stuff about whatever the new light-thing is.

The thing to replace LEDs, at least partially in street lighting and floodlighting (not domestic) will likely be plasma, and it may well be within your lifetime, the technology is already in use for horticulture and film lighting, and streetl lights are being developed, with indiana even already installing some! http://luxim.resilient.lighting/technology/case-studies/40-600-indiana-street-lights-upgraded-to-lep

The thing to replace LEDs, at least in street lighting and floodlighting (not domestic) will likely be plasma

Nope - this technology has been tried and tested for over two centuries now, and developed as far as it possibly could (you do realize that "plasma" is precisely what is inside HID and other discharge lamps?). As for Luxim's systems, their burners is simply filled with mercury vapor and doses of indium and holmium iodides. It's not different than a quartz metal halide lamp, except for the thermal management and the lack of electrodes. This, combined with a relatively inefficient microwave driver (around 75 % conversion efficiency, standard electronic drivers for lamps exceed 90 %), results in system efficacies well below those achieved with current CHM lighting systems...

The problem with plasmas is that the processes underlying their emission of light cannot be controlled and tuned as precisely as in semi-conductor junctions. This depends on the electron-atom interaction cross sections and on the energy levels of atoms and molecules, factors that are fixed in nature and that cannot be tailored to increase the lumen efficacy over empirically reached levels.
In LEDs, the production of light is much more fundamental, it is achieved via the recombination of electrons and holes (lack of electron in a material), and this process does not depend on the fundamental properties of atoms and molecules. This way, there are many more degrees of freedom available to "lamp" designers than with electrical discharges. That's why the highest ever efficacy achieved with plasma lamps reached ~220 lm/W, while LEDs have already passed the 300 lm/W mark. And the striking thing is that in the former case this was achieved with a nearly monochromatic light, while this was done with white light in the latter case...

The next revolution in lighting, one which will bring the efficacy levels even closer to theoretical limits, will definitely involve simpler and more fundamental ways of light production, i.e. the simple oscillation of electrons in metal-oxide structures, without any of the thermal issues that plague today's LED technology based on semi-conductor junctions. This will provide the ultimate freedom in the design of light sources.
Nevertheless, this is still quite far in the future and the next evolution in lighting will be the rise of efficient phosphor-less LED systems, first with the solving of the so-called green gap in the efficacy curve of LEDs.

I think LEP is still a form of HID lamp, but without electrodes. But there is one problem: It is only available in cool daylight color light, and is based on proprietary light source and gear, like in the case of LED and induction lighting, meaning that no replacement lamp will be available after the OEM lamp will reach EOL, and the whole lantern needs to be replaced.

What is the theoretical limit of conversion of energy into light Max....isn't it about 630 lm/W at about 550nm...looks like they are half way to the "magic garden"!

Do you have any idea of the CRI of these 300 lm/W sources or is that still a trade secret?

Dor - LEP IS an electrodeless HID lamp technology, "Light-Emitting Plasma" is only some marketing bulls**t used on the unsuspecting crowd: all plasmas emit light, it's one of their core characteristics.

As for your remark about the need for changing luminaires, this is no longer true. LED systems are now coming in modular designs where the light engine or the ballast can be changed at will. Only you will find this in quality products, not in low-cost garbage.

Globe Collector - the theoretical limit depends greatly on the light color and spectrum. For the photopic peak at 555 nm, the maximum is 683 lm/W, not 630, so there is indeed quite a lot of room for further progress. As for the CRI of the white light produced from 300+ lm/W devices, it is a low value for sure, around 50-60 Ra8 if I remember correctly.

If LEP is a marketing term for an electrodeless HID lamp, so the electrodless sulphur lamp, which was a commercial failure, is also considered "Lighting Emitting Plasma".

Dor, ALL discharge lamps have a "light-emitting plasma" at their core.

Max, to say that HPS is completely obsolete is just plain short-sighted, while LED is more efficient, you're missing out on a lot that LED doesn't offer. It's stuff like actual optics, light that won't keep you up at night, aesthetics, lack of sky glow and easy-to-repair fixtures, that you're missing out on when LED systems are used. Also, you migh say that it's like using a small electric car over a pickup truck. The car might go the same speed and take you the same places, but the truck offers lots of handy features like towing and a bed to put big and bulky items on.

Plasma can be different colour temperatures, cinema lights can even do them on the fly, it's just, as with LEDs, the most lm/W CCT is usually chosen.

Also Plasma is not as simple as just being an electrode-less HiD like Induction is to Fluros, as the temperature of Plasma is higher, so much more black body radiation is emitted than with traditional HiD which relies primarily on spectral emission, giving plasma a fuller spectrum.

Plasma also has higher power density than HiD and much more than LED, as well as no flicker which is valuable especially for stadiums, theatre, films and certain manufacturing and testing applications.

Max, to say that HPS is completely obsolete is just plain short-sighted, while LED is more efficient, you're missing out on a lot that LED doesn't offer.

...like crappy color, flicker and poor optical control of light?

It's you who's totally missing the whole point; you think that electric-powered trucks will never be a reality in the future? That general-lighting HID is not already obsolete and its market is not running on momentum alone right now? and that this momentum will eventually be reduced to zero? if so, crawl back to your cave.

@ Bert Bright - you really have no idea what "plasma" is or mean and you clearly have no understanding of the technology. Have you actually used, modeled, designed and actually made HID lamps? Have you actually used, measured, dismantled and characterized electrodeless lamp systems of the sort made by Luxim? I have. It's clueless people like you who bring a lot of nonsense in places like LG...

I step out from this thread, reasoned discussion has become impossible because of the sheer ignorance and generalization here.

...like crappy color, flicker and poor optical control of light?

It's you who's totaly missing the whole point; you think that electric-powered truck will never be a reality in the future? That HID is not already obsolete and its market is not running on momentum alone right now? and that this momentum will eventually be reduced to zero? if so, crawl back to your cave.

1. Crappy color? Loads of people here hate the cold white light that LED has, and HPS won't keep you up at night so much.
2. Flicker? CWA ballasts are quite good regulating that lamp, and the flicker is comparable to LEDs.
3. Poor optical control? Your fixtures in Europe might be different than the ones here, but we've got a reflector and a textured refractor to control the light, this works crazy well and I have a fixture that I can get a photo of to prove it.
Also, gasoline/diesel has something interesting about it, something cool, most people realize this, and by the way there are hybrid trucks available but those are crazy rare.

Dor, ALL discharge lamps have a "light-emitting plasma" at their core.

So its looks to me like whats happens here with the "Light-emitting plasma", is that Luxim (If the terms "LEP" and "Light-emitting plasma" was indeed coined by Luxim) promoting its lamp using a misleading ad campaign, which is similar to Samsung "LED TV". Meaning that "LEP" or "Light Emitting Plasma" may become a generic name for an electrodeless metal halide lamp, like "Xenon" and "HID" were for automotive metal halide lamps and "LED" for LED backlit LCD TVs.

It's clueless people like you who bring a lot of nonsense in places like LG...

I step out from this thread, reasoned discussion has become impossible because of the sheer ignorance and generalization here.

Can you show me the generalizations used here?

Guys.....Guys....Cool It before you all suffer cardiac arrest or sub dural hematomas!!!!!!!!!!!

History will take its course and it is the the collective decisions of the BILLIONS of people out on this Planet who will decide it, we are just mere "insects".

well Max, if you know so much and people are claiming incorrect things, then why not correct and explain them the error of their ways?

Instead you're just dismissing them with no evidence at all that they're actually wrong or what your knowledge may, or may not, be.

It's you who's totaly missing the whole point; you think that electric-powered trucks will never be a reality in the future? That HID is not already obsolete and its market is not running on momentum alone right now? and that this momentum will eventually be reduced to zero? if so, crawl back to your cave.

@ Bert Bright - you really have no idea what "plasma" is or mean and you clearly have no understanding of the technology. Have you actually used, modeled, designed and actually made HID lamps? Have you actually used, measured, dismantled and characterized electrodeless lamp systems of the sort made by Luxim? I have. It's clueless people like you who bring a lot of nonsense in places like LG...

I step out from this thread, reasoned discussion has become impossible because of the sheer ignorance and generalization here.

Just wondering (and don't take this the wrong way please) but why do you come off as so, well, rude? You seem to be like this in a lot of threads when it comes to stuff like this. Everyone can have their own opinions on things (I do too) and just because someone isn't the most knowledgeable on a subject doesn't mean they need to be put down for it.

You don't have to like them, but you do have to put up with them because they are here to stay and replace the inefficient HPS, LPS, MH, and MV.

I could expound quite significantly on the various efficiencies of different light sources, but given this thread has become somewhat heated, I won't say much, but I do invite you and anyone else with an interest in the subject to visit me here in Aberdeen and see the "efficiency" of the LED fittings that have been forced upon us.

At the end of the day, as the people who are eventually paying the bills (through our taxes) shouldn't we have some say in the matter..?

Sorry to open up this thread again..

Sometime in May of 2018 I went back & measured the actual LUX levels on the ground for the pictured HPS and LED, and for a number of adjacent lights, plus more along the area.

At the nadir on the road below each head, using the same ebay lux meter, approximately..:

I measured the pictured 71w GE Evolve at 17 lux. The range for others was between 15 and 18, with 17 & 18 lux being a very common level. Nearly always this was the peak. Moving away from the nadir, the drop-off was gentler than the HPS heads at 12-14 lux at nearly 45 degrees from the nadir.

The pictured HPS head had 10 lux at the nadir and 11 lux just a little on the side. However, other 250w heads had a range of between 21 and 30 lux. The lowest was 9 lux...so the pictured head was (is) quite depreciated. On the other hand, a GE M-250A2 FCO adjacent, also w/250 HPS sticker, had a whopping 40 lux on the ground.

So on average, the new GE Evolves are now a little more than half the lux of the aged 250w HPS. Still, not bad, excellent for up-light reduction. (OVZ heads have ~ 3-5% direct up-light).

Forgot to mention that I had pictured and measured many more HPS systems as a comparison to future LED (or CMH or LEP) conversions. Little did I know that some of these heads were changed less than a year from when I photographed them.

That's crazy how big of a difference white light makes.

I measured the pictured 71w GE Evolve at 17 lux. The range for others was between 15 and 18, with 17 & 18 lux being a very common level. Nearly always this was the peak. Moving away from the nadir, the drop-off was gentler than the HPS heads at 12-14 lux at nearly 45 degrees from the nadir.

And now compare these figures with the illumination standards, as quoted herein. This installation easily surpasses them. (In fact the former 250 watts were overkill from the start, but that's another story.)

Concerning the heated debate just this link as a reply to the argument how glary LED lights are, compared to the nice, soft, warm and gentle HPS.

Concerning the heated debate just this link as a reply to the argument how glary LED lights are, compared to the nice, soft, warm and gentle HPS.

To be fair, those are foreign lanterns that are designed differently from cobraheads. Drop lens HPS cobraheads do have glare, yes, but the glare from these GE devolve fixtures is much worse (there are some in my area) since the light is coming from a smaller surface area.

Can you show me the generalizations used here?

I'm still wondering what generalizations were used here

I can attest that the new GE Evolve heads, the light-source being more concentrated, have greater disability glare than the HPS refractors.