Lighting-Gallery.net
Lamps => Modern => Topic started by: dieselducy on February 25, 2009, 11:33:13 PM
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I am beginning to believe that MV is better. WHY are the fixtures no longer made? i was in lowes today and MV has a 24,000 hr life and the MH only has a 10,000 life? and the MH is more than twice the price!! why?
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On January 1 2007 or 2006, the US goverment banned the sale of, importing, and manufacturing, of mercury vapor fixtures or ballasts. Why? We here at LG aren't sure, but we neither aren't happy about it. MV bulbs are still sold for existing fixtures but production of these may stop soon. Probe Start metal halide are also being banned soon. It is true that Metal Halide has a better CRI but at EOL metal halide lamps can explode. If you want a MV fixture, many websites still sell them and people on LG here can help you find one.
- lightman64
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The price depend on demand: As MV fixture sale is banned, there is low demand, so the price went down. Secons, as the MV is well known and very mature technology, many companies are able to make them, so there is taff competition, cutting prices, so their margin down. And moreover MV's last long, so not making much business.
As MH is the only white alternative, there is large demand, so it allow manufacturers to make more money. As this is more challenging technology, there are fewer players able to make useable lamps, so this allow for higher margins, so retail prices.
Btw. I have stronger and stronger feeling, then this is the real motivation for most "environmental protection" laws, same with incandescent ban:
Prices are so low, so not possible to make money on them. Regular fluorescents are not promoted, even if technically superior (you don't have to make so many compromises), as they are not making as much money - they last too long.
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Medved, I wholeheartedly agree with what you are saying. Everything does come down to the almighty dollar. No one really cares what everyday citizen's preferences are. We live in a political universe. Why else would MV be banned by people who know absolutely nothing of its efficacy and reliability, except for the mentality that just because something is, as you said, "mature" technology MUST automatically be bad? And Dark Sky, they favor the usage of ugly yellow-orange light to white light? Makes no sense at all. Light pollution in an orange color is more of a pollutant than that from a white light (and go figure--clouds are white.) Why make the sky look like orange sherbet? ???
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Mercury Vapor is indeed better....it last longer and doesnt go Boom at the end of its rated life,also very reliable...while HPS Fixtures are Cycling mercury vapor fixtures are still opperating.
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For streetlighting there is one feature MV's would not meet: Point-like light source except uncoated types (but these are really not efficent).
If you want to send the light into required pattern with high efficiency, your optics has to be much larger then your light source. To have reasonable size lantern, you need really small area source, so why MH win there.
And the lifetime is only one design parameter, beside of many others. And as everywhere else, there is nothing best in all categories, so you should make compromises.
Few decades ago the electricity was cheap cheap in US, so the major cost of light was cost of lamp replacement. So a long and reliable life was a prime importance, so every design modification was evaluated with first question "How it affect the life?". That's, why we have 24+k life rated mercury lamps in US.
Then an energy crisis arrived and we see huge move towards "more efficient" lamps and first HPS boom. But before lamps might be marketed, the crisis was over, so the lifetime return to it's prime importance.
But now, when the energy costs are already much longer and higher, so nobody expect the return, the matter of prime importance become the efficacy and the "card flip over": First question is "How it will affect the efficacy?"
So we have second "HPS boom", at least fortunately with more suitable ballast and lamp designs.
Beside this, people are more demanding for aesthetic aspect, so when the money allow, they want high quality white light. And for this higher quality light category MH's do offer cheaper solution - the energy cost would be higher for MV then CMH. Part is, because those quality demanding areas are small and dense, so relamping is not as expensive (compare to rural areas, where you need to travel miles to change one bulb).
There is even a difference between EU and US (in the top of MV era): Lamps for US are rated 175W, 45lm/W, 24+khours, while practically the same lamp for Europe was rated 250W, 60lm/W, 15khours. The European rating just run the lamp hotter - so the efficacy rises, but the lifetime shorten. It was so, because in Europe was cheaper relamping (more dense installations), but more expensive electricity, so in Europe was OK to sacrifice the life in order to improve the efficacy. One interesting result: Such hotter-running lamps more likely fully die at their EOL, instead of being unnoticeable dimmer and dimmer...
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Well, I hope that cool white CMH (or even QMH) replaces HPS as fast as possible and brings the MV atmosphere back, at least partially...
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MVs last longer and don't break. At work we have 1000W MHs in enclosed fixtures above the swimming pool, these are lots of fun to relamp and not spill any glass in the pool.The Philips ones shatter the most.
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Hmm, at my local hardware store in bailey, i found a 175 watt MV area light! hmm it was 75 dollars. it was taped, so was it returned? hmm, kinda funny that they were selling an MV light after the ban...
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I like the white light more than this unkindly orange aggressive light. Here in Germany(beginning in the fiftys) they want that all lanterns light white like the moon. Exclusion were a part of the gas-laterns in Berlin. We used for the most part flourescent tubes and for big Places we used HQL High-steam-pressure-quicksilver-lamps.This lantern had need a lot of power. Thanks to the night-electricity we could used the big lanterns we invented. But later the power was being more expensive and the citys replaced at first the big lanterns with the white light and later the flourescent tubes. Now we have a lot of this lanterns with ´´baby-lamps´´. Here in Germany they had banned light-bulbs with 100wattage , next year the 60wattage light-bulb and the HQL want they ban this year in parts of Germany.
In my opinon this is the wrong way.
I hope you can understand my English.
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Well, I hope that cool white CMH (or even QMH) replaces HPS as fast as possible and brings the MV atmosphere back, at least partially...
At Dresden a good amount of lights in the centre have during the last years indeed been changed over from HPS to MH, in some cases presumably using retrofit lamps (Osram has a 70 W MH lamp that can be used in place of a HPS lamp). And yes, I think this is a considerable improvement, resulting in a much more pleasant atmosphere.
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Last weekend I was visiting with my relatives in southern Finland. There, I first time saw MH cobrahead used as a streetlight. I have usually thought that MH is only used in decorative lightning and other "not basic lighting" but plain cobrahead with reasonable wattage(dimly litt street) lamp was pretty nice combination. Night was pretty foggy and I thought that this could be how it seemed when incandescent lamp was still used in streetlighting as they used pretty warm white MHs. I did not have a camera with me so its no picture.
still, MV is number one. MH is coming in good second in HID lamps
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I like mercury vapor better than HPS or MH, metal halide contains more mercury in it than mercury vapor and always tends to explode, also high pressure sodium creates an unpleasant orange haze at night (even full cutoff ones) and isn't very visable at night. This ban is ridiculous and no one in their right minds would of ever thought about passing this law in the first place. All these special interest groups and the government shouldn't have any say so about what lights we can and can't use outside, it's not their business.
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I'm pretty sure we've established Mercury vapor lamps have more mercury per lumen than any other.
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I'm pretty sure we've established Mercury vapor lamps have more mercury per lumen than any other.
@Xytrell, think before you comment on this!
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I remember values around 10..30mg for MV, 3..10mg for CMH (both depend on exact type) of ~6..8klumen output range (125W MV, 70W CMH).
But for MH the mercury amount would strongly depend on used fill mix. I believe, then probe-start Na-Sc will have higher mercury content (similar size arctube as in MV, but higher pressure), but new CMH's use way less mercury then MV's, mainly as the mercury is not anymore the main light emitting substance, but play "only" a support role (startup, arc stabilisation, atmosphere "solvent" in high pressure mode,...).
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HPS and MV lamps both have 24,000 hours rated life. But MV lamps failure mechnism is failing to ignite (Like the fluorescents) as the electrodes becomes deplated emmiter, while the HPS lamps failure mechnism is cycling as the increase voltage during life in them is cause not by the electrodes emitter depleting but by sodium loss from the arctube that is usually accurs before the electrodes reaches EOL. Like MV lamps HPS can also survive for >10 years, as accured for example in the former HPS lamp in the Thorn Pilote fixture that pointing to my mother home (The lamp just stop from operating when reached EOL and not cycled at all).
Also MH lamps have a shorter life then the MV lamps as the electrodes of the MH lamps have a more stressing on them because the higher loading of the arctube (This is the reason why the electrodes glows a bright yellowish white light after a MH lamp is turned on).
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I like the color of many MH lamps because they are warmer and have a higher CRI. They can really improve the atmosphere of downtown and streetscapes when used in conventional street lighting fixtures.
However, the color varies so much, depending on age of the lamp and also by manufacturer. They look great when they are new but turn blue and dim with age and of course can explode at EOL if not regularly turned off for periods.
MV color is much more constant over the life of the lamp and the change is more gradual. SV lamps don't seem to change in color with age but they begin to cycle at EOL.
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yes, I hate it when there are discolored MH lamps more than anything else :P
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Personally, i preferr MV :)
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For streetlighting there is one feature MV's would not meet: Point-like light source except uncoated types (but these are really not efficent).
If you want to send the light into required pattern with high efficiency, your optics has to be much larger then your light source. To have reasonable size lantern, you need really small area source, so why MH win there.
I know that this is a really old topic, but there is something I would like to add; I have noticed that cobraheads using coated lamps provide smoother illumination that isn't very shadow-y. With clear lamps, the illumination isn't very even. This is the same with LED fixtures.
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Yes, coated lamps will always provide smoother distribution, at the sacrifice of lumens (except for /DX MV, which gets more lumens from the coating). This is the whole purpose behind "soft white" incandescent lamps, because shadows are "softer" and the light is less harsh. Coated HPS and MH lamps are used when a more diffused, even light is desired and slight loss of lumens is not minded.
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For MV lamps the phosphor coatings can actually increase light output and improve color reproduction.On HPS lamps the coating does reduce the light output.
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For MV lamps the phosphor coatings can actually increase light output and improve color reproduction.On HPS lamps the coating does reduce the light output.
But the diffuse light does not allows the optics to be made as efficient as the bare arctube allows, so when measured towards the usable light output (that contributing to reach certain minimum illumination level) you can not reach as high system efficacy as with clear lamp.
But that does not mean all lanterns using clear lamps (or LED's) really do shape the beam efficiently, it really depends on the actual lantern design and compromises to be taken...
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I know this is a really old topic, but this section caught my eye:
And Dark Sky, they favor the usage of ugly yellow-orange light to white light? Makes no sense at all. Light pollution in an orange color is more of a pollutant than that from a white light (and go figure--clouds are white.) Why make the sky look like orange sherbet? ???
Now I happen to like sodium lighting, but that isn't the point. The reason Dark Sky (and any astronomer for that matter) prefer sodium light is because it is easier to filter out in telescopes and so makes astronomical observation much easier. See here (https://palomarskies.blogspot.co.uk/2009/05/why-astronomers-love-low-pressure.html) for details.
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I know this is a really old topic, but this section caught my eye:
Now I happen to like sodium lighting, but that isn't the point. The reason Dark Sky (and any astronomer for that matter) prefer sodium light is because it is easier to filter out in telescopes and so makes astronomical observation much easier. See here (https://palomarskies.blogspot.co.uk/2009/05/why-astronomers-love-low-pressure.html) for details.
Plus the orange light does not affect Wildlife as much as the white light does.
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Were there really issues with wildlife being affected by white light, say form MV lamps, before the days of HPS? Other than sea turtles I was never aware of any major wildlife issues caused by white light at night. And who cares about astronomers. :D Never understood the whole big deal about space exploration personally. We need to sort out our own issues here on earth before we start causing issues on other planets... ::)
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It's actually LPS lamps that astronomers prefer, as it is monochromatic it is far easier to filter out when viewing the sky.
You may not care about them, but it is a valid science. There are many amateur astronomers out there too, their hobby is just as valid as any of ours. Astronomy isn't just about space exploration, there is much that can be learnt from observing the galaxy that can be of benefit to us here. See this article (https://www.quora.com/How-does-astronomy-benefit-mankind) for just a few examples.
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Were there really issues with wildlife being affected by white light, say form MV lamps, before the days of HPS? Other than sea turtles I was never aware of any major wildlife issues caused by white light at night. And who cares about astronomers. :D Never understood the whole big deal about space exploration personally. We need to sort out our own issues here on earth before we start causing issues on other planets... ::)
Astronomy is important because we can find out how things happened here millions of years ago, and hopefully stop the big environmental issues that are affecting our planet, like the loss of proper diurnal habitats for the wildlife.
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Were there really issues with wildlife being affected by white light, say form MV lamps, before the days of HPS? Other than sea turtles I was never aware of any major wildlife issues caused by white light at night. And who cares about astronomers. :D Never understood the whole big deal about space exploration personally. We need to sort out our own issues here on earth before we start causing issues on other planets... ::)
http://www.earthisland.org/journal/index.php/elist/eListRead/led_streetlights_save_energy_but_could_have_some_serious_side_effects/
https://m.phys.org/news/2017-02-major-impact-wildlife.html
http://www.darksky.org/why-is-blue-light-at-night-bad/
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Were there really issues with wildlife being affected by white light, say form MV lamps, before the days of HPS? Other than sea turtles I was never aware of any major wildlife issues caused by white light at night. And who cares about astronomers. :D Never understood the whole big deal about space exploration personally. We need to sort out our own issues here on earth before we start causing issues on other planets... ::)
The thing is, with the coming high efficacy light sources there became way more and way stronger light sources installed everywhere.
It goes so far, although the efficacy of the light sources is now 10x than it was 100 years ago, the total power consumption used for lighting becomes 10x higher as well. That means today we emit 100x more light than we used to. And that is the main problem for the light pollution in general.
The thing is, the lower cost of the artificial lighting promoted its way wider use, include the "architectural lighting" (illuminating everything, mainly with light sources shining upwards) madness.
And regarding the LPS (as a monochromatic light source) sometimes presented as a solution to the light pollution:
Although the astronomy is very important, the light pollution impact on other life, humans as well as wildlife is important much more.
So although LPS may solve the light pollution problem for astronomers, for the rest even the monochromatic light is still the same light pollution. And because the LPS is way harder to control (the beam pattern) than the real HID or LEDs, it becomes way more potent source of the light pollution than most other light sources (maybe except fluorescents, but these are not that wide spread for the outdoor street light duty).
So the LPS solution may make sense really in the close vicinity of the observatories, as general lighting they makes the light pollution only worse.
The only working solution to the light pollution is to really generally reduce the use of artificial illumination mainly outdoors. Illuminate only what needs to be illuminated and with only just enough intensity, not more.
I think it is generally happening, at least partly: Because the LED system prices generally scale with power rating, there is a strong incentive for the utilities to really specify the minimum power needed for the lighting. With HID this was not the case: Very frequently the lower power system cost the same, sometimes even way more than its higher power brother, which led utilities to keep using the same power (e.g. 250W HPS or MH in place of older 250W MV) even when the new source had way higher system efficacy (very often a modern 70W HPS or MH with good beam control was able to perform the job of an original old 250W MV system).
By the way the LEDs should be able to lessen the problem really generally, if properly used and designed (include color quality - without aiming to too high CRI). They are small and compact, so rather easy to control their beam to illuminate what is needed without any significant light spill, with most energy in one blue line, so similar as LPS easy for astronomers to filter out the residual glow from that most energetic component). Of course, for e.g. observatory parking lot and such close proximity that may not be sufficient, but those could well be lit by e.g. narrow band green-blue LED types (they are way less efficient, but still offering good optical control and monochromatic output; we are talking about special use where the efficacy does not have to be of the top priority).
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Were there really issues with wildlife being affected by white light, say form MV lamps, before the days of HPS? Other than sea turtles I was never aware of any major wildlife issues caused by white light at night. And who cares about astronomers. :D Never understood the whole big deal about space exploration personally. We need to sort out our own issues here on earth before we start causing issues on other planets... ::)
Sorry to say this: you are incorrect with saying 'who cares about astronomers'.
If we only think about solving our own problems here on earth, then for example we don't know what asteroid to deflect which means our days are counted. I'm a big fan of Neil Degrasse Tyson, check out his talks on this topic. Astronomy and astrophysics play a very important role in everyday life, without it we can't leave this planet when it's time to go.
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Our days are numbered anyway. We are running out of oil, global warming is affecting out future food supplies, and other natural resources are at risk as well. Plus little rocket man wants to destroy the world with his nukes.
My comment was partially a joke (hence the smily) and I'm well aware of the good that astronomy has done but that said, there are other more pressing matters to attend to in my opinion...
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Our days are numbered anyway. We are running out of oil, global warming is affecting out future food supplies, and other natural resources are at risk as well. Plus little rocket man wants to destroy the world with his nukes.
My comment was partially a joke (hence the smily) and I'm well aware of the good that astronomy has done but that said, there are other more pressing matters to attend to in my opinion...
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:D
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I like the meme, dam near choked on my coffee..
And for the most part Astronomy installations get very good co-operations from locals when they explain the importance, even places like Hawaii they have filtered yellow LED lighting for streetlighting, just look at the area around the Green Bank Observatory, for 20 miles you can't even use Cellphones, Wifi, or microwaves it is effectively a 13.000 square mile radio quite zone if you look at the map and they expect dead silence around the observatory, so if people are willing to give up there iphones they will change there lights as well to help with astronomy...