Vu1 – a new one

January 11, 2012 at 12:34 pm (LAMPS, Vu1)
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After CFL and LEDs, now a completely new lamp technology from an independent company is finally about to enter the market!

Quoting part of the October 2010 introduction from the C|Net  article “Vu1 readies efficient lightbulb Edison would love“:

Vu1 (pronounced “View one”) today said that it received UL certification for its first lightbulb which it says matches the light quality of incandescent bulbs but uses a fraction of the energy and costs less than current LEDs.

Its technology, which the company calls electronically stimulated luminescence (ESL), is derived from cathode ray tubes used in televisions, said president and CEO Philip Styles. Electrons are fired at a bulb coated in phosphors which are excited and emit light. The effect is a “natural light,” which is the same as a traditional incandescent, Styles said.

“It’s basically old technology that everybody just gave up on some years ago because it’s based on the TV side, not lighting,” he said.

Because of the phosphors Vu1 is using, it can better match the light spectrum of incandescent light than competing technologies, Styles said.

Its first product, which Vu1 intends to start making early next year, is an R30 floodlight for recessed cans which produces as much light as a 65-watt incandescent at 870 lumens while consuming 19 watts. An Energy Star-compliant compact fluorescent light with similar output consumes about 13 watts. But unlike compact fluorescent bulbs, Vu1 bulbs will not have mercury. The cost is projected to be under $20, said Styles.

And now the day has come!

Well, almost… Last Friday, ahead of official launch date, Lowe’s started selling the long-awaited Vu1 lamps online (for a lower price than projected, $14.98) but only a few lucky buyers were able to place an order. Yesterday, the Vu1 corporation CEO  issued a letter explaining why. It seems Lowe’s need to revamp their website to create a new product category since the Vu1 will not fit into existing lamp categories. Once that’s taken care of, online order should work again.

Early reports from those who received their bulbs are mostly positive regarding light quality. (I’ll be back with a review if I can get hold of one myself.)

And two days ago Vu1 issued a press release (here quoted from Market Watch) which announced that:

Scott Blackstone, CEO, will be presenting at the Needham & Company 14th Annual Growth Conference on Thursday, January 12, 2012, at 3:30 pm ET. The conference is being held at the New York Palace Hotel in New York City. Vu1 Corporation will offer a live audio webcast of its presentation at 3:30 pm ET on January 12, 2012, at http://wsw.com/webcast/needham49/vuoc.ob/ 

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LED drawbacks

January 10, 2012 at 5:34 pm (LED)
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Time to write a little summary about solid state lighting a.k.a. LED and what has transpired over the last couple of years.

Coloured LED

As I’ve written before, I’m all for the use of coloured LEDs as replacement for holiday light strings, night lights, exit signs and traffic lights that are used for so many hours per day.

Warm-white LED

But I have yet to see a warm-white LED that looks like a decent incandescent replacement. I went to the Nordic Light Fair again last year too but the warm-white LED lamps had not much improved. (I’ll keep checking.)

Cool-white LED

The glaring cool-white LEDs I find hard on the eyes and not at all suitable for Scandinavia, where we are used to the warm glow of incandescent light in the winter time. Two years ago they tried replacing the lamps by the creak in one of Sweden’s most picturesque little towns to cool-white LED, but had to remove them quickly as the result was ghastly and people complained. Now that town is lit by incandescent-looking ceramic metal halide and warm-white good quality CFLs, which is ok even though quite not as pretty and romantic as when it had real incandescent lamps along the creek.

I also recently checked out an LED-lit tunnel in Stockholm and found the bright cool-white light dangerously glaring. Much more so than the standard linear fluorescent or sodium HID lamps usually used in tunnels (and I’m not crazy about those either). Shops lit with LEDs tend to look cold and sterile, rather than warm and inviting. Could be that I’m female, many men seem to love the cold harsh light. Here is a similar opinion from another woman:

Whenever I try to study in Meriam Library I feel like I’m on an examination table in a surgery room. Either that or in a jail cell or a mental institution. The lights are overly bright and they make a buzzing noise that interferes with my ability to concentrate. I’ve stopped going. /…/

Now, whenever I walk up the Esplanade to get home at night, I notice that the LED bulbs cast a sharp bluish-white light that brightens the whole street. I understand that peripheral visibility will greatly increase for drivers, but they are just too bright.

They remind me of Meriam Library but on greater scale.

If these energy-efficient bulbs take over streets and even in-house lighting, you have to ask yourself – do I want everything around me to feel like a night game of football or baseball?

What’s worse is that these lights will affect space observatories in cities across America, causing an effect that doesn’t seem be taken as serious as when smog from cars damages air quality. That effect is called light pollution.

LEDs are actually more dangerous than the old incandescent bulbs because they cause a glare for drivers and create more shadows, said Kris Koenig, director of the Kiwanis Chico Community Observatory.

“Cities are going to want to open light again where they’ve been restricting light for decades,” Koenig said, in a phone interview. “There are even studies that show that light at night causes sleep problems for humans and animals.”

LEDs trade comfort for brightness

Toxic LED?

And last year scientists found that LEDs – like most electronic products, surprise surprise – contain some toxins too.

“LEDs are touted as the next generation of lighting. But as we try to find better products that do not deplete energy resources or contribute to global warming, we have to be vigilant about the toxicity hazards of those marketed as replacements,” said Oladele Ogunseitan, chair of UC Irvine’s Department of Population Health & Disease Prevention.

He and fellow scientists at UCI and UC Davis crunched, leached and measured the tiny, multicolored lightbulbs sold in Christmas strands; red, yellow and green traffic lights; and automobile headlights and brake lights. Their findings? Low-intensity red lights contained up to eight times the amount of lead allowed under California law, but in general, high-intensity, brighter bulbs had more contaminants than lower ones. White bulbs copntianed the least lead, but had high levels of nickel. /…/

Ogunseitan said that breaking a single light and breathing fumes would not automatically cause cancer, but could be a tipping point on top of chronic exposure to another carcinogen. And – noting that lead tastes sweet – he warned that small children could be harmed if they mistake the bright lights for candy.

LED products billed as eco-friendly contain toxic metals, study finds

I must say that I find that risk a lot smaller than accidentally breaking a CFL at home and breathing the mercury vapour. Breaking an LED is not so easy (although I managed to drop one and broke the outer bulb) and you normally don’t pulverise them (“don’t try this at home!”). But they should absolutely be recycled as electronic waste and not thrown in out with household garbage.

(As an aside: In connection with this article being quoted around the web I’ve also seen some erroneous claims that incandescent lamps contain mercury – which is not true at all – and lead, which used to be true but not after 2006.)

Long-life LED?

Promised longevity may also not be what one expected:

When it’s said that a standard light bulb will last 1,000 hours, that is the mean time to failure: half the bulbs will fail by that point. And because lamp manufacturing has become so routine, most of the rest will fail within 100 hours or so of that point.

But LED lamps don’t “burn out.” Rather, like old generals, they just fade away.

When a manufacturer says that an LED lamp will last 25,000 or 50,000 hours, what the company actually means is that at that point, the light emanating from that product will be at 70 percent the level it was when new.

Why 70 percent? Turns out, it’s fairly arbitrary. Lighting industry engineers believe that at that point, most people can sense that the brightness isn’t what it was when the product was new. So they decided to make that the standard.

Of course, brightness is subject to the old frog in the boiling water syndrome. I’m sure that most people won’t even notice the lower level then, if they’ve lived with the same bulb for its entire life.

How Long Did You Say That Bulb Would Last?

Philips & Color Kinetics explains it more in detail:

This 70% of the level of original output is called L70 by the lighting industry. ASSIST recommends defining useful life as the length of time it takes an LED light source to reach 70% of its initial light output (L70). For decorative and accent applications, ASSIST recommends defining useful life as the length of time it takes an LED light source to reach 50% of its initial output (L50).

So up to 30-50% is seen by the lighting industry as a perfectly acceptable level of light loss just because we get used to it over time??

Testing also seems difficult, making one wonder how the life span numbers given for LEDs are arrived at:

LM-80 requires testing of LED light sources for 6,000 hours, and recommends testing for 10,000 hours. It calls for testing LED sources at three junction temperatures — 55° C, 85° C, and a third temperature to be determined by the manufacturer — so that users can see the effects of temperature on light output, and it specifies additional test conditions to ensure consistent and comparable results.

Unfortunately, LM-80 provides no recommendations on how to extrapolate measured data to L70 or L50. Such a methodology, IES Technical Memorandum TM-21 is currently under development. Until TM-21 is published, the only way an LED source manufacturer can claim that their L70 and L50 figures conform to LM-80 is to measure their LED sources until they reach those thresholds. Since a typical L70 number is 50,000 hours, such a test would last longer than five years! Not only would this test be impractical, but LED technology evolves so quickly that a given product would be obsolete by the time the test was completed. [Emphasis added]

Philips & Color Kinetics: Useful Life Technical Brief

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LED luminaire review

February 25, 2010 at 12:24 am (Lamp reviews, LED)

After seeing it on the Northern Light Fair I wanted to test one of Lampkonsulenten‘s floor spot luminaires with warm-white high-quality LED in a home setting, as a reading/bed light.

Info: Price around 1 500 euro. Expected lamp life around 50 000 hrs.

Impression: Compared with an equivalent halogen floor spot of similar model, it actually lit up the pages of a book better and enhanced the contrast. LED light is very directional and this was no exception so it really focused all light on the book. However, when trying it for mood lighting it did not sparkle and spread the light around the room like the halogen lamp; the light sort of faded mid-air. When used as sole illumination, it made the room look a bit cool, dead and gloomy.

From these observations I draw the following conclusions:

1. A bit of incandescent/halogen light is clearly needed in order to create a warm and alive feel to the room. LEDs should thus be used as complementary light for specific tasks, or for decoration, not as primary light source.

2. LED is by nature a directional light source and should be used as such. Trying to get it to spread light in all directions like a standard bulb will just scatter the light so that the bulb illuminates little more than itself.

3. LED light is best utilised at fairly close range when using it for illumination.

4. Warm-white LEDs may need to have an even lower correlated colour temperature than incandescent lamps in order to appear as warm.

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Northern Light Fair

February 14, 2010 at 12:58 pm (Lamp reviews)
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Yesterday I was at the Northern Light Fair in Stockholm to check out the latest lamps.

CFLs

I have to say I was pleasantly surprised by most CFLs displayed. Both Osram, Megaman and italian Leuci had CFLs in good incandescent-like colour, looking decently bright too.

One of Osram’s displays. The lamps left and middle are CFLs, and the 5 to the right are decorative incandescent (which looked brighter in real life).

LEDs

While the LEDs certainly have improved since my last visit to the Light Fair two years ago, there are still huge quality differences between different types of LEDs.

First I checked out the holiday lights; strings, icicles, candelabras etc.

As usual, coloured ones were great, the cool-white horrid, and the warm-white ones of varying quality. Some were pink-white, others ugly yellow, but a few were actually very incandescent-looking, so clearly they are improving. However, only in light colour, not in light output.

In this picture the difference between the somewhat pale LEDs (to the left) and the glowing traditional incandescent strings (to the right) is clearly visible, even though it is clearer in real life.

Strings with many little light points still work as decorative lights, but in the candelabras there wasn’t enough light to radiate outwards, just a dull and gloomy glow inside the little bulbs, clearly not nearly as bright as the incandescent candelabra next to it and not at all giving that warm Christmas feel that you want from an electric candelabra.

In this picture the real incandescent candelabra is the glowing one in the lower left corner. The duller ones that don’t radiate are LED.

Next, I looked at non-decorative LEDs. Again I found great quality variations in the various attempts at producing bright warm-white light. I was not impressed with any of the LED retrofit bulbs from Osram, Megaman and Leuci. Bleak light, colour not quite right, still insisting on the less-than-great idea of putting LEDs in a retrofit bulb etc.

The best LEDs came integrated in luminaires from Norwegian luminaire company Lampkonsulenten. Their high power LEDs were of a completely different quality class and came in white and warm-white light which both looked decently incandescent-like and decently bright and radiating (as far as I was able to tell in this well-lit commercial setting; I’d have to try one at home to see if this impression holds). Compared to these quality LEDs, all others on the fair looked like a joke. But it made me a bit more optimistic regarding the options available for professional lighting designers even if their output is still limited and the quality not quite as high as real incandescent light. But I think they would do well compared with metal halide for example, at least quality-wise.

Halogen

Both Osram and Leuci had excellent halogen energy savers. The Osram representative said it is technically possible to make halogen lamps much more effective even without the integrated low-voltage transformer (which Philips use for their B-class halogen lamps) but it requires more R&D so they want to be sure there is enough market for it before investing and didn’t seem in a hurry to do so before EU bans C-class lamps in 2016.

So do let them know if you’re interested in even more effective halogen lamps now! If you like real incandescent light, this is the replacement to go for.

Luminaires

On the luminaire side, I found a great variety and much creativity. General trend seems to be softer shapes compared to the cold, hard designs that totally dominated the market just a couple of years ago, fewer black lamp shades (finally!) and much playfulness, e.g. integrating decorative LEDs in the design, using new materials in creative combinations, and making crystal chandeliers that truly look like something from this century.

Just a brief example.

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White LED Reviews

January 11, 2010 at 9:22 am (Lamp reviews, LED)
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Here I’ll review LEDs as I find them. The last two at the bottom are new for today. (Prices include 20% VAT and may vary between countries.)

* 1.2W Anslut ‘warm-white’ GU10 20-point reflector lamp

Info: 20-diode spotlight. Price was decent for an LED, just over 6€.

Impression: Don’t quite know what to make of this one. On the one hand it’s impressive to get so much light – at least in one direction – out of what is only 1.2W!

I picked this particular lamp because the light looked more white than the markedly green-white or blue-white I’d seen previously. It seems to have decent colour rendering too, both to the naked eye and in my DVD-test where I could see the full spectrum reflected without any large visible gaps (though no magenta).

Colour: Still slightly green-yellow-white (which is not surprising as ‘warm-white’ LEDs usually consist of blue diodes with yellow filters). Some may like this slightly cooler light (around 3000K, but gets a little warmer over time) but for my personal taste it still looks too much like FL light and gives my kitchen an industrial feel which dos not complement the warm colours and traditional design in a good way.

I have to say I was disappointed as I prefer mercury-free LED before CFL and would love to find a good enough LED to recommend instead. For commercial purposes fine, but not for home lighting unless that industrial feel is what you prefer. I’ll keep looking.

* 1.8W Kjell & Co ‘warm-white’ frosted E27 mini globe

Info: Price around 12€.

Impression: This lamp is a joke. It’s not even remotely warm-white, it’s cool-white like a moon-beam, and about as dim. It gives only 65 lumen, less than a 10W incandescent, which is good for absolutely nothing. You certainly can’t read in it and it’s not warm enough to be used as mood-lighting (except at a Halloween party perahps). And this was the brightest LED globe light I could find in Stockholm retail stores!

Looking at the small print on the back of the package it says this lamp type is recommended “for decoration” or “for dark spaces like the cellar stairs, the attic passage-way, the garage or storage area”. But it is not decorative, just dim and generally gloomy, now why would anyone want to put such a light in their cellar stairs and risk breaking their neck, or in spaces that are usually already creepy enough without adding a dim ghost light to it?

The only reasonable application would be as night light, but as this bulb requires a real luminaire with a full E27-socket, which makes it useless as night light too. (Instead, see my Coloured LED Reviews for a really great LED plug-in nightlight that costs only slightly more.)

* 4W clear ‘warm-white’ SMD E27 mini globe

Info: Price around 19€. Rated life 50 000 hours. 350 lumen or “about as much light as a 40W incandescent but using 1/10th the energy”. Will not get warm, light up 100% in half a second.

Impression: Yes, like all LEDs it lights up instantly and is luke-warm enough to touch even after being on for a while.

Colour: Warm-pink-white that looks similar to ‘warm-white’ fluorescent light rather than to golden-white incandescent light.

Brightness: Nowhere near that of a 40W incandescent. The 350 lm may be correct but a 40W incandescent gives 410-505 lumen and visual comparison between an incandescent 40W lamp seems to confirm it, so this seems to be another case of consumer fraud.

At the same time it is too glaring to the naked eye and must be used in a lamp with a thick shade so that the glaring little dots don’t shine through. Which reduces its brightness even more as it is designed to throw light to the sides rather than downwards. Tried it in different luminaires. In modern table- & floor luminaires it doesn’t work very well: what little light that finds its way out of the shade is very dim and gloomy indeed, and of no use whatsoever. A classic architect luminaire seems to be the only one it works with. The wide shade spreads the light much better than the very directional GU10 spotlight. In this luminaire it reading works if you can ignore the faint light dots reflected on the page.

Light quality: Like the other LEDs, the spectrum of this one is continuous in the warm end of the spectrum but spiky in the blue end, with no magenta. Colour in the room look sort of dampend, as if seen through a grey filter. Whatever room I try it in, it turns all gloomy and depressing. No life.

* 3W Cree ‘warm-white’ frosted E14 mini globe

Info: Price around 24€. 120 lumen or equivalent of a 25W incandescent. 50 000 hr life. Ceramic foot and chromed aluminium house.

Impression: The frosted glass makes this one easier on the eyes and works well enough to read in. The socket limits its usefulness as its long heat sink makes it stick out too far in all the various E14 reflector luminaires I have. Putting it in a luminaire with a shade will reduce light output too much. The best fit would probably be in a vanity light for those who want a non-glaring white.

Colour: Cool-pink-white. More like fluorescent light and even less incandescent-like than the Osram CFL tested above.

Brightness: Again erroneous equivalence info. An 25W incandescent lamp gives 215-235 lm so a 120 lm should not be enough to replace it. However, this one actually seems even brighter than a 25W incandescent, though the light itself has a duller quality.

Light quality: Continuous spectrum but with green, violet and magenta missing. Colours in the room tend to look a bit grey and faded and white surfaces look distinctly cool-pink, even though the bulb itself looks more neutral-white.

* 2W Osram Parathom ‘warm-white’ clear E27 Classic A

No picture but it looks like a normal size version of the mini globe above (= diodes on a stick stuck in a clear bulb).

Info: Price around 16€. For in- and outdoor use. 25 years claimed life.

Impression: Another useless LED. Very dim light, good for nothing. What Osram calls ‘warm-white’ is green-white. Even putting a peach shade on it does not remove the green tint. Not pleasant or attractive! Complete waste of money if you ask me.

I hope we don’t have to wait another two decades before Osram gets their WLED phosphor mix right.

* 3W Cree ‘warm-white’ GU10 1-point spotlight

Info: Price around 23€. 1-point spotlight with 60 degree beam angle.

Impression: Fairly bright for only 3 watts. This one too had green-white light. Not nearly good enough to replace my GU10 halogen spot.

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CFL Reviews

January 11, 2010 at 8:55 am (Lamp reviews)
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Splitting up my review of various energy saving retrofit lamps as I test them in a home environment. This post will focus on compact fluorescent lamps. The first lamp review is moved from my original post, the second is new for today. (Prices include 20% VAT and may vary between countries.)

* 7W Osram Duluxstar ‘warm-white’ E14 frosted CFL mini globe

Info: Appearance-wise, one of the most incandescent-like CFLs on the market, with a correlated colour temperature (CCT) at 2700K. CRI around 80 = standard (mediocre) colour rendering capacity. Price: about €10, but if you want a decent-looking (and decent-performing) CFL, be prepared to pay for it.

Impression: Visually, the light looked very soft and incandescent-like in the shop, but at home it still has a touch of that pink shade typical of flourescent light, though less markedly so than its early predecessors, more warm-pink than cool-pink, and admittedly an improvement compared with older CFLs and all the cheap budget lamps on the market.

Size-wise it only fit in one of my reflector luminaires.

As for colour rendering capacity, my do-it-yourself-spectral analysis with the back of a DVD shows the spectrum cut up into distinct bands with all the wavelenghts inbetween missing, as is normal for standard-quality FL light.

It does look bright enough to replace the promised 40W bulb (now in the beginning, will fade with age) though it took several minutes to reach full output. And the light was actually nicest before it did. Now it has turned a little more pink-white and makes the room look uniform and sterile. Many may not notice that much of a difference from an incandescent, or care if they did. But as I have a very well-developed sensitivty to such nuances, I could not relax in such a light and would never use it in my home.

* 8W Osram Duluxstar Mini Twist ‘warm-white’ E14 spiral CFL

Info: Correlated colour temperature (CCT) 2500K (“warm comfort light”). CRI around 80 = standard (mediocre) colour rendering capacity. Light flow: 470 lumen. Price: about €6. Made in China.

Impression: With even warmer light (= lower CCT) this one actually looks very much like incandescent light colour-wise = more golden than pink. Still a bit flat due to the lower CRI but definitely the best incandescent-copy I’ve seen so far.

Size-wise it is too big for all my different reflector luminaires, even though this is the most compact spiral CFL model I’ve seen. I can screw it in just fine but half of it sticks out. The part that is visible is very glaring. Calling my bf:s attention to the experiment, his first response was a loud “ouch” as the glare pierced his eye, and I got a dark afterimage in my visual field for several minutes afterwards from looking at it just briefly. I’d recommend it only in luminaires with shades.

Brightness seemed OK too. 470 lumen is even a bit more than the equivalent 40W incandescent (410 lm) with margin for the eventual light loss.

Nice job, Osram! Only took 2 decades to finally get it (almost) right.


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Holiday Lights

December 9, 2009 at 8:10 pm (Holiday lights, LED)
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Everything seems to be about holiday lights now, with new LED light strings using a fraction of the usual energy, with almost no fire risk if installed correctly.

Do I recommend them? Yes and no. Depends on colour.

Coloured - yes! No reason whatsoever not to switch to LED.

Cool-white – no. For the holidays you want to create a warm fuzzy feel, right? Using chilly ice-blue LEDs is not the way to do it. *brrrr*

Warm-white – maybe. It depends on how keen you are on getting an exact incandescent replacement. If you are, there aren’t any. What is sold as “warm-white” tends to be either pink-white, yellow-white or greenish-yellow. How much they’re off from the brilliant golden-white of incandescent lights varies between models and brands. Some are close enough to be acceptable. Make sure to look and compare before you buy.

Maybe you don’t care as long as there is light? Then by all means, do buy them! Being left on perhaps all night and even all day for a whole month or two, it can be well worth the investment. Just get ones that look good enough for your standards.

Here are some tips from Gadget Guy on how to calculate savings: What Holiday Lights Are Best?

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Car Headlights

December 3, 2009 at 12:27 am (Car headlights, LAMPS)
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Replacing the standard warm-white top quality halogen light, commonly used for headlights, with other light sources is in my opinion not a good idea. 

Since their introduction in early 1990′s, more and more cars have been equipped with discharge xenon arc lamps. They’re about twice as bright as halogen headlights or more, and are said to improve visibility for the driver. But what few seem to have considered is how irritating they can be for meeting traffic:

- They’re blueish (around 4100K), which creates more confusion and distraction in an otherwise even traffic stream. Lights from meeting cars are not supposed to attract your attention by sticking out. And blue light is not good for the eyes. 

- An especially irritating feature is that they flicker and quickly shift shade from blue-white to purple-white and back as the car drives past, instead of giving a calm, even light like halogen does. This can be very distracting for meeting traffic.

- They’re very bright and glaring. That’s not good for for road safety. Being blinded and distracted in crucial traffic situations is not exactly helpful.

The Swedish Road Administration say they keep getting complaints from other drivers but can’t do anything about it since these lamps tend to get approved by EU as car manufacturers apply. A condition for this approval is that they must be precisely adjusted so as to avoid glare for others, but this is obviously not always done, or is easily maladjusted again depending on packing weight etc.

- Getting a xenon-lit car driving behind can be even worse than briefly meeting one, especially if it’s a van or SUV where the headlights come up higher. Having the inside of one’s car lit up like a stadium does not make for safe driving. 

If you’re considering switching to xenon, please be mindful of other drivers and consider staying with traditional halogen if possible. If you the car is already equipped with xenon, please make sure lights are well adjusted at all times.

Also beware of Faux Xenon, e.g. Osram’s Cool Blue – “the designer lamp”- a product that shouldn’t exist. Putting a blue filter on a standard halogen bulb is about the stupidest thing you can do. These should definitely be banned, as they are both energy inefficient and dangerous!

Nowadays, headlights in general are also much brighter than they used to be - manufacturers constantly boast about how much more light their product will give you:

* Osram Silverstar “Thanks to their special technology SILVERSTAR lamps illuminate the road with an up to 50% brighter light in the crucial zone 50 to 75 m in front of the vehicle than a standard lamp”

…and in the crucial vision zone of meeting traffic, pedestrians and bicyclists.

* Philips X-treme Power “Philips X-treme Power bulbs deliver up to an astounding 80% more light than standard halogens”

…right into the unsuspecting eye of everyone but the driver.

If the European Commission ever wanted to do anything truly useful, why not ban xenon lights as a safety hazard, faux xenon as a waste and hazard both, and set firm limits to how bright headlights can be?

Update 1: Now LED lamps have been introduced for car headlights. Very bright white light that at least doesn’t flicker and shift like xenon light, but it is still chillingly cool-white and quite glaring. For some reason, many SUVs are equipped with LEDs – which is an extra bad idea since the light is even more glaring coming from that hight.

However, using red and amber LED lamps as stop- and signal lights in the back of the car is a great idea! Producing coloured light while using practically no energy, is what diodes do best. 

Update 2: SCENIHR, the Scientific Committee on Emerging and Newly Identified Health Risks, in its amended report 2011, page 72, actually mentions glare from meeting traffic as a real hazard for night drivers:

“Glare from bright head lights may induce accident”

http://ec.europa.eu/health/scientific_committees/emerging/docs/scenihr_o_033.pdf 

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Lamp Guide

September 23, 2009 at 3:22 am (Halogen, Incandescent, Lamp guide, LED)
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Now that the market is being flooded with such a confusing profusion of different lamps to replace the incandescent bulb, it is more difficult than ever to find the right lamp for the right place.

Swedish national TV consumer program Plus last week tried to sort it out with the help of Kalle Hashmi at the Swedish Energy Agency, STEM. [1] My translation of his unusually informed and balanced recommendations:

* In closed luminaires it is not advisable to use CFLs as they get too hot which shortens their life. Where you have very short burning time, such as in a closet or the bathroom, the lamp life will shorten significantly if you turn it on and off a lot. In such a situation you could preferably choose a halogen lamp.

* If temperatures are too low [= outdoors in northern winters] the [CFL] lamp does not perform at its best. The lamp is made to function best in 25 degrees [C]. In such a situation we think the best option is to use an induction lamp. Very expensive but on the other hand it lasts 100 000 hours.

* When you get older, 60+, you need more light to be able to see, and our ability to distinguish colours and contrasts diminishes. Then we need to choose a light that solves all three problems.

* When it comes to contrast, for example, it is usually limited to reading text, black on white. Then you need to choose a CFL with higher effect, e.g. 15W and you can use a correlated colour temperature around 4000K, but only for reading.

* When in a situation where colour rendition is very important, where you need to match colours, then it is very important to use a mains voltage halogen lamp because it has much better colour rendering capacity. It can be a situation like cooking, where all colours seem matte to the eyes. So what an elderly person perceives as ‘brown’ may actually be burnt. With halogen you see better.

* CFLs are not the answer to all our prayers. When it comes to colour rendering they are not as good, and they also contain mercury. LEDs will be the dominating technique, but it’s better to replace low voltage spotlights with LED spotlights than replacing standard bulbs for general lighting.

My comments: Good advice all of it, except for the recommendation to use cool-white CFL for reading. Some research suggests that contrast decreases rather than increases with higher correlated colour temperature (blueness) and that certain blue wavelenghts may harm rather than help in cases of macular degeneration. [2] The small traces of UV which some naked CFL tubes emit may at close range may also worsen cataracts and skin conditions. [3] If you sit closer than 30 cm for more than an hour per day, the the British Health Procection Agency recommend that you use a covered CFL with an extra outer bulb. [4] I would instead recommend frosted incandescent or halogen for reading, as clear bulbs tend to give disturbing light patterns on the page and most LEDs are either too dim or too directional. Unfortunately, thanks to the European Commission, that’s no longer an option.

Replacing spotlights with LED is a better idea as LEDs are already directional by nature and perform better as reflector lights than as omnidirectional light trapped in a bulb – if you don’t mind the slightly lower light quality and paler colours which can be seen clearly in this comparison between ‘warm-white’ & ‘daylight’ LED and incandescent downlights [5]:


More tips:

* For those who prefer a daylight-simulating light despite the lower contrast, white LEDs are naturally cool-white and need no special phosphor mix like CFLs, or neodymium filter like incandescents, to achieve a daylight look. Daylight lamps usually look best in the daytime. At night the cold light can look and feel more unnatural when contrasted against the dark as we humans are traditionally used to fire light at night (though cultural and individual preferences may vary).

* Where warm-white incandescent type light with perfect colour rendering is needed, there exists no replacement other than halogen. No CFL or LED has that special sunny feel and warm glow which makes colours come alive. The next best thing after halogen would probably be metal halide HID reflector lamps, but they’re usually too bright to be used at home and require special luminaires.

* In traditional environments with antique furniture and art, CFLs and LEDs tend to look particularly out of place, whereas they may look acceptable with more contemporary designs, even if a bit dull. 

* When it comes to mood lighting of your dinner table, cosy corner or favorite restaurant CFL and LED have zero romance factor whereas the warm light of halogen or incandescent spots on dimmers will complement candle light and create an attractive, romantic and relaxing atmosphere. In rooms where you’re mostly sitting down and relaxing (like the living room), use many low-watt (7, 15 or 25 watt if incandescent) lamps placed low around the room, e.g. on walls, tables or in windows, rather than one bright ceiling light. Can be complemented with floor reading lamps and ceiling floodlights to be turned on when needed. Avoid up-lighters. 

* Around children, I’d use only warm-white LED lamps (which are cool to the touch) or incandescent lamps in enclosed & shaded luminaires. CFLs contain mercury and can break and should therefore never be used around children or pets. Clear halogen lamps can get too hot, bright and glaring. One exception is IKEAs Snöig series of desk-, wall- and floor luminaires where the halogen lamp is well protected from curious fingers and eyes.

* For night-lights, I would use LED. Even if you only save 6 watts per lamp, they’re usually on all night, every night, and come in different colours. 

* Coloured lights, e.g. holiday lights, car and traffic signal lights, stage lighting etc. can be replaced by LED. LEDs come already coloured and are often ideal due to their smallness, low energy use and lack of excess heat. Paying for premium quality incandescent light only to filter out most of through a colored glass is truly a waste! 

More photo comparisons between different lamp types can be found here:
Snarkish Forum
Newest Lightbulb Tech Combines Advantages of Incandescent, Fluorescent, and LED
LED Tints

TreeHugger CFL guide:
Be Careful When You Shop For Compact Fluorescents

Lighting design tips:
GE Lighting Style
Philips Lighting for the Home
Philips Lighting Design tool

References:
1. Plus, SVT, 17 sep 2009 http://svtplay.se/t/102796/plus
2. Artificial Lighting and the Blue Light Hazard
3. SCENIHR: Light Sensitivity
4. HPA – Emissions from compact fluorescent lights
5. Picture from Breakthrough Design Cuts Cost of LED Light Bulbs by 40 Percent

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The Bizarre Ban

September 7, 2009 at 4:15 am (EU ban, Incandescent, INCANDESCENT BAN)
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Back to researching & blogging after a month of well needed rest…

The EU incandescent ban

The first phase of the absurd incandescent ban has now taken effect.

* As of this month it is now illegal to produce and import 100W incandescent bulbs and frosted incandescent bulbs. And frosted Halogen Energy Savers!

(Selling already existing stocks is still permitted.)

The regulation also includes requirements for new product information on the packaging for all lamps (which I think is a good thing that should have been required long ago).

Manufacturers support this phase-out. “We are very positive”, says Magnus Frantzell, CEO of the Swedish Lighting Manufacturers Association to Expressen. Well, what a surprise…

But it will not stop here. This is the full schedule:

* 1 September 2010: clear 75W (over 750 lumen) lamps will be banned (through minimum efficiency requirements).

* 1 September 2011: clear 60W (over 450 lm) lamps will be banned.

* 1 September 2012: clear 7W-40W (over 60 lm) lamps will be banned.

* 1 September 2013: tightened standards on CFLs and LEDs. No lamp type will be removed from the market, only lamps with poor performance. Possibly non-dimmalbe lamps will be banned.

* 2014: Review of the regulations by the EU Commission.

* 1 September 2016: tightened standards for clear halogen lamps. Only energy class B halogen lamps (C for some special cap lamps) will be permitted, which currently only the super-expensive IR halogen lamps with integrated transformer reaches. All other halogen lamps will be banned! [1]

Exceptions: “special-purpose lamps designed essentially for applications such as traffic signals, terrarium lighting and household appliances and clearly indicated as such on accompanying product information are not subject to these eco-design requirements.” Examples of special-purpose lamps: aquariums & terrarium lamps; germicidal lamps, lamps for display/optics; stage, studio, TV & theatre lamps; photo flash lamps; projection lamps, IR lamps; traffic signal lamps for roads, trains & aviation; car headlight lamps; oven & fridge lamps; temperarture- & shock-proof lamps; mirror lamps. [2]

Street, office & industry lighting

Somehow, without any public debate whatsoever, it seems that the EU Commission has also just snuck through a regulation on office, industry and street lighting. [4, 5]

* 2010: Phase out of T8 halophosphate fluorescent tubes (through minimum efficiency requirements).

My comment: This is good as they are not very efficient, contain more mercury, often flicker due to old type magnetic ballasts and the poor-colour-rendering light truly sucks. Should have been phased out decades ago.

* 2012: Phase out of T12 fluorescent (FL) tubes.

My comment: This is probably good too, although it will require many businesses to purchase new fixtures for the thinner, more efficient tubes with HF-ballasts.

* 2012: Phase out of high-pressure sodium (HPS) standard quality lamps (only E27/ E40/ PGZ12 affected).

My comment: This is acceptable as long as there are better quality lamps of the same type available. Not acceptable if it includes the decorative frosted incandescent-like lamps used in parks and Old Town-environments across Europe. These are somewhat less efficient but are needed for sensitive environments. Quality vs quantity. It cannot all be about quantity of light, we also need quality of life.

* 2012: Phase out of less efficient metal halide (MH) lamps (only E27/E40/PGZ12 affected).

My comment: Again fine, if there are better lamps of the same type still available.

* 2014: Review of the regulations by the EU Commission.

* 2015: Phase out of Hígh-Pressure Mercury (HPM) lamps.

My comment: Excellent! Should have been banned decades ago, as soon as there were HPS or MH replacement lamps available for the same lumnaires. HPM lamps are most commonly used as street lights in cities. They give a truly horrid purple-white light which tends to turn green with age, contain more mercury than other lamps and are markedly less efficient than HPS, MH and CMH lamps.

The new warm-white Ceramic Metal Halide (CMH) are about twice as efficient and give a very incandescent-like light: truly great for street & park lighting.

* 2015: Phase out of plug-in/retrofit high-pressure sodium lamps (= direct replacement for HPM). Plug-in lamps must correspond to Super/Plus HPS level; almost all plug-in/retrofit lamps will be banned.

* 2017: Phase out of Poor performing metal halide (MH) lamps: (only E27/E40/PGZ12 affected).

My comment: Seems that the EU consultants and Commission are hell-bent on removing any light from the market that is remotely attractive and human-friendly. Warm-white MH lamps, and improved colour HPS lamps are the most incandescent-like alternatives after halogen. Phasing out these lamps may mean that there will be no frosted HID lamps left on the market, despite their usefulness commercially indoors. The Eco-design group does not care how the lamp is used, light quantity at all cost is their only goal.

It also means that every EU country will be forced to replace the whole street luminaire when stocks of replacement lamps run out. This will be good for the environment but may be more costly than some countries or counties can afford. Why not instead give special EU grants or other incentives to those who install the most energy efficient technology available, instead of removing whole lamp groups from the market??

Reflector lamps

As mentioned earlier in this blog, reflector lamps is the next group up for slaughter. [6] Preparation is going on currently and decision will be taken next year.

Halogen replacement bulbs for spotlights, floodlights and downlighters are at high risk of being recommended for phase-out, making millions of expensive desklights, spotlights and recessed luminaires useless as there are no CFL or LED alternatives for these tiny bulbs or tubes. Great for the luminaire market but not so great for the individual home owner who may have invested a gread deal of money into installing recessed fixtures etc.

Professional lighting designers despair at the thought, as should many galleries, shops, restaurants, hotels etc. as they will then no longer be able to create the uniquely luxurious and attractive lighting environments for their customers, made possible only with halogen spots.

If the lobbyists that keep pressuring the EU Commission into such follies have their way, we will be facing a very cold, dull and drab lighting future.

The logical thing to do would be to ban only the poorest performing lamps in each lamp group, since each lamp type has its own unique qualities that oftan cannot be replaced by another lamp type (the only exception being HPM lamps for which replacement with HPS, MH or CMH is an improvement both quality- and quanlity-wise).

* As no other lamps can replace small halogen bulbs for reflector lamps, neither quality-wise or size-wise, only the poorest performing in this class should be banned, not the whole group.

* As frosted incandescent lamps cannot quality-wise be replaced by anything but frosted halogen lamps, the ban on the latter should be lifted.

1. New EU directive: Say goodbye to the light bulb (Osram summary)
2. EuP Directive About Non Directional Domestic Lighting (detailed slide show)
3. EU directive – special purpose lighting (Osram summary)
4. EU directive – street, office and industry lighting (Osram summary)
5. Commission Regulation (EC) No 245/2009 of 18 March 2009 (original document)
6. Spotlight and downlighter bulbs next to be banned by EU

4 Comments

Coloured LED reviews

July 30, 2009 at 11:16 pm (Lamp reviews, LAMPS, LED)
Tags: , , ,

Here I’ll be reviewing coloured LED lamps.

* 1.1W Osram Lunetta Colormix LED night-light

Info: Plugs right into the electric socket and has a little button at the bulb base: each new click gives light blue, hot pink, cool green, soft orange, bright blue, alternating and no light. Also has a light sensor and turns itself off in the daytime or when ambient light is bright enough. Rather sophisticated for being the size of a golf-ball and will probably last ‘forever’. Price about 15€.

Impression: Love this one! LED technology used for what it does best: produce coloured decorative/lead light at extremely low wattage and heat loss. Is hardly even warm when you touch it. Great for kids!

* 3W unknown brand RGB E27 LED

Info: Remote-controlled LED retrofit lamp that can replace a standard bulb. Light output 140 lumen. Price about 36€ (incl shipping).

Impression: I wanted to know a) if I could get a more natural looking warm-white by tuning it myself and b) if I’d be able to create any shade imaginable. The answer to both is “no”. a) The white is nowhere near white, but a visible mix of different colours. b) The 16 colours are pre-set and cannot be adjusted manually as I had mistakenly assumed. A home spectral test with a DVD shows the blue-green part of the spectrum very clearly, then a dip in the yellow-orange area, then a nice bright red and no magenta. Lighting food and clothes with it made red bell peppers and a blue robe look almost fluorescent.

But what did I think of it otherwise? Well, the truth is that I love it anyway! What is probably an unintentional design flaw – that in mixed colours it shows the mixing colours separated into concentric rings instead of being displayed as a smooth blend – actually makes its light beam uniquely special, intriguing and pretty, as long as one does not need a white light to see well in. It’s purely decorative, but very much so!

This is what its beam looks like on my pebble-patterned desk:


* 7W Philips Living Colors RGB LED


Info: Remote-controlled indirect floodlight that puts colour on a white wall. It does what I thought the simple RGB lamp would do: with the remote control it is possible to choose any hue by scrolling on the colour circle, and fine-tune both colour saturation (from deep to pastel) and light intensity (from bright to dim) to the desired shade. Price about 150€. Also comes in a mini-model for around 100€.

Impression: I’m fairly impressed with this one. Very cool futuristic design: a decorative object in itself. Almost the size of a soccer-ball (though more resembling a small gold-fish bowl with a goth vase in it). Nicely designed and easy-to-use remote as well.

Great light for mood & decorative purposes. Not sure about the “16 million colours” – that’s probably more theoretical than practically achievable – but it seems to have enough versatility to let one create one’s favorite hue and shade fairly exactly. Except a good white, just various pastel tints (which are nice in themselves, though not perfectly white).

I’ll give it 4½ lightbulbs out of 5. One of the most fun and versatile lighting products I’ve ever seen! I especially like the possibility of creating pastels, as they make the room brighter and create a softer and more sophisticated lightscape. I’m finding that I can easily change it to match the dawn outside my window as it gets brighter and sunnier.

Example of how the beam looks on my (unfortunately not flat) white wall when I tune it from softest pink to brightest red:




YouTube has some videos of varying quality of how it looks while shifting colours:

Update 1 Aug: After using it as general lighting in my home office for a couple of days instead of my halogen two-way desk-light, I find that it has an odd side-effect on my vision. Directly after using it and turning it off, all natural light looks strange and ‘fluorescent-like’ for a while until my eyes have readjusted to normal lighting. I’ve noticed this with the other RGB LED as well. This does not happen even after a whole day staring at my CRT screen.

Update 4 Aug: I first thought the explanation might be the odd spectral distribution unique to LED in general, but it’s probably as simple as the light in the RGB LEDs being coloured and hyperstimulating the cones. After using the warm-white GU10 LED spotlight as desk lighting for a day, I do not get this effect.

4 Comments

Halogen Energy Saver Reviews

June 9, 2009 at 8:57 am (Halogen, Lamp reviews)
Tags:

Here are reviews of retrofit halogen energy savers. Brief descriptions + my personal, subjective impressions of how they look in my home environment. (Note: prices are converted from SEK to Euro, include 20% VAT and may vary between countries.)

* 28W Osram E27 clear A-lamp

Info: CRI 100 (= full colour rendering). Costs about twice as much than its incandescent equivalent, uses about 20% less energy (though advertised as 30% less) and lasts twice as long.

Impression: Looks exactly like the 40W incandescent equivalent it’s supposed to replace, though slightly brighter and with a rather glaring light point so best for luminaires with a shade.

* 28W Osram Spot R50 E14 reflector lamp

Info: CRI 100. Costs only slightly more than its incandescent equivalent, uses 20-30% less energy and lasts twice as long. 

Impression: Looks exactly like the 40W incandescent it’s supposed to replace. And when I say “exactly”, that means exactly and not “more or less similar”, since halogen is an incandescent light, only concentrated into a smaller inner bulb.

* 30W Philips Master Classic E27 frosted A-bulb with infra-red coating and integrated transformer

Info: A low-voltage retrofit lamp that can be used in a standard mains-voltage luminaire. CRI 100. Costs over 10 times as much (€13) due to the built-in electronics, but then it lasts 3000 hours, so divide that by 3 and then deduct the 50% electricity savings and it’s not so bad.

Impression: This one too gave a nice warm-white incandescent light that looked bright enough to replace a 60W bulb, as it promised. I could not tell it apart from a standard 60W frosted bulb.

Update Dec 2011: I’ve not used this one very much at all, just as a desk light on those few occasions when I’ve worked on something not on the computer. Yet one day a few weeks ago it just died. I have definitely not used it anything close to 3000 hours. And this is the only type of incandescent bulb that will be permitted in the future, if the European Commission doesn’t change its mind. (OK, one bulb does not make a proper consumer test, I could just have been unlucky.)

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More lamp descriptions can be found on this site: http://lightbulbmarket.blogspot.com/

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CFL Analysis – Conversion Charts

March 29, 2009 at 6:16 pm (CFL ANALYSIS, Conversion charts, Incandescent)
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European recommendations

In Europe, CFLs are often claimed to give “5 times more light” (or “up to” 5 times more, to cover poorer performing covered, reflector and decorative bulbs). Optimistic calculations on potential savings are almost always made on the nominal initial lumen/watt values of the best performing bare tubes. A typical European equivalence chart may look like this:

These recommendations are, however, quite misleading as those who follow them will get less light than they originally had! Astonishingly, this EU Quality Charter for Fluorescent Lamps accepts lower minimum initial claimed lumen output from an equivalent CFL than what a typical incandescent bulb usually gives (first two columns of this table):

As can be seen in the last two columns (which I’ve added for comparison) incandescent (“GLS”) lamps usually have a higher lumen output than minimum EU requirements for equivalent CFL! [1]

If a typical CFL does not produce as many initial lumens as the lamp it is supposed to be replacing, it cannot possibly be said to give “5 times more light” of incandescent energy use.

Light Reduction

As explained in under Life span, CFLs give even less light as they age. After 2000 hours, the EU Quality Charter accepts a 12% light loss for bare CFL tubes, 17% for covered CFL bulbs, and 25% for both types at the end of their life.

To illustrate how this works out in lumen output for various wattages, I’ve used lumen figures from manufacturer catalogues [1, 2, 3] for standard incandescent (GLS) A-lamps and a typical good quality CFL bare tube. In the following columns I’ve deducted the permitted 12% and light loss after 2000 hours and the actual mean light loss for recently tested CFL tubes of the same brand after 6000 hours [4]:

Here I’ve deducted the permitted 17% and 25% light loss for double envelope CFL bulbs (a real test showed 15% and 27% for this particular model). [5] In the manufacturer’s catalogue, it is sold as “saving 80% light” (= giving “5 times more light” than an incandescent) but as we can see here, it is less than 3½ with light loss included in the calculation.

To get the same lumen output as from an incandescent bulb, and to compensate for the expected reduction in output as the CFL ages plus the poorer light quality, one needs to choose a higher watt CFL than usually recommended (just like professional lighting designers often do when installing new lights, as they are well aware of these factors). This will, however, give a light that may be too bright and glaring in the beginning and too weak and dull towards the end of its life.

Thus, when used in real situations, an Energy Class A-rated, good quality CFL bare tube does not give 5 times more light, but 3-4 for some of the most effective CFLs on the market. Covered CFL bulbs give somewhat less initially and lose more as they age (a mean of 25% loss for Philips and Osram bulbs, and 30-100% for IKEA bulbs in 2008 test). [4]

1. Philips Lighting
2. OSRAM
3. Hawells-Sylvania
4. Råd & Rön 1/2008
5. Råd & Rön 7/01

North American recommendations

U.S. and Canadian ENERGY STAR requirements stay more reasonable and require a minimum initial lumen output that roughly translates to a 3:1 or 4:1 switch. [1, 2]

Again required initial lumen output is slightly less than incandescent output and light loss is not taken into account, despite General Electric being more open and giving mean lumen values in their online catalogues.

As can be seen in the above example, a fair switch is closer to 3 than 4 for the most effective bare tubes, and of course less for covered bulbs, globes, reflectors and decorative bulbs. Yet on the same page, it is still claimed that

“ENERGY STAR qualified bulbs use about 75 percent less energy than standard incandescent bulbs.”

1. U.S. ENERGY STAR
2. Canadian ENERGY STAR
3. GE Lighting

Summary

Based on manufacturer figures for initial lumens, with light reduction included, the best tubes give only 3-4 times more light in Europe and around 3 in the U.S.A and Canada. Less for covered, reflector & decorative CFLs, for CFLs used in the wrong luminaires, and for poorer quality CFLs of all types.

Consumers therefore need to be advised to choose a higher watt CFL than recommended to get as much light as from the original bulb and to compensate for the eventual light degradation and poorer quality of the CFL replacement. And the EU standardisation directive needs to be adjusted to reflect reality.

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CFL Analysis – Light Quality

March 29, 2009 at 2:59 pm (CFL ANALYSIS, Incandescent, LED, Light quality)
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When it comes to light quality, there exists no replacement for the incandescent lamp, other than mains voltage halogen in retrofit bulbs – most of which are also being phased out!

What is so unique about incandescent light then? * Unlike other light sources, incandescent and halogen lamps are tungsten black-body radiators, a version of fire-light which humanity has evolved with since fire was discovered. Like sunlight, incandescent light has the highest possible colour rendering (CRI 100), due to naturally continuous spectrum, and a warm-white, human-friendly light which radiates and makes colours come alive.

Update 25 june: Lighting designer Ed Cansino in a recent, highly informative interview:

“…if I were forced to choose the best lighting for residential overall, it would have to be incandescent. I feel that we as humans have had a deep connection to flame for many thousands of years. It’s almost like it’s in our DNA. It’s interesting that as time moves on, people are still drawn to sitting around the camp fire, a fireplace, even a barbecue. Think of a Yule log. It’s just that this particular quality of light is ingrained in us. You can even get a screen saver of log flames. Incandescents with their glowing filaments are a form of flame and are thus an extension of this inborn affinity that we have for fire.”

* When dimmed or used at lower wattages, the light colour gets proportionally warmer and more like candle light. Increase brightness and it gets whiter again. This is how a natural light source behaves.

* Incandescent light is the standard against which all other types of light is measured. This is why the lighting industry has put so much effort into trying to copy its light colour, colour rendering capacity and other qualities.

* CFLs are based on a completely different technology, and LEDs on yet another. Even if the industry can now mix phosphors to decently emulate incandescent light at a superficial level in some of the best brand models, FL/CFL or LED light is no more the same thing as incandescent light than a gold-coloured alloy can be called real gold, or synthetic microfiber real silk. Both have their respective uses, but in many cases a substitute just won’t do. CFL light is a composite light, an artificial replica of the real thing that just doesn’t feel the same and does not behave in the same way. When dimmed, for example, it just turns cooler and more grey and dull, not warmer.

See this interview with a pro-CFL professor explaining the quality problems with CFLs: Why Efficient Light Bulbs Fail to Thrive

Here are spectral distribution charts (from Osram) for different light sources, which illuminate the quality differences very clearly:

Incandescent light with continuous spectrum and full colour rendering (CRI 100).


Example of standard FL/CFL with uneven spectrum & limited colour rendering (CRI 82-85).

White LED, a smoother curve but peaking in the blue end of the spectrum instead of the red.

Ron Rosenbaum describes the difference more poetically:

“I’ve tried the new CFLs, and they are a genuine improvement—they don’t flicker perceptibly, or buzz, or make your skin look green. There is a difference, and I’d be in favor of replacing all current fluorescent bulbs with CFLs. But even CFLs glare and blare—they don’t have that inimitable incandescent glow. So don’t let them take lamplight away. Don’t let them ban beauty.

“Don’t get me wrong, this is not a plea for Ye Olde Times, for gaslight and quill pens. It’s just a plea not to take for granted the way we illuminate our world. Not all change is improvement. Why do I put such a premium on incandescence? For one thing, I am a bit romantic about it. A lamp fitted with an incandescent bulb and dim translucent shades casts a lovely, painterly glow on human faces, while the light of fluorescents recalls a meat locker.

“Why do you think there is such artistry to so many lampshades? They are the lingerie of light.

“But the appeal of incandescence is not just a matter of romance. I suspect there are also answers to be found in the physics and linguistics of incandescence.

“I’d speculate that it has something to do with the different ways light is created by incandescents and fluorescents. Incandescent light is created by heat, by the way an electric current turns a thin metal filament (usually tungsten) red then white hot in a transparent or translucent globe filled with an inert gas that prevents the filament from burning up, allowing it to give off a steady glow. (That explains the warmth: The fact that incandescence emanates from heat creates warmth, distinguishes it from the cold creepiness of fluorescence.)

“Fluorescent light bulbs, on the other hand, are coated inside with chemical material that lights up as energy reaches the tubes. (It’s a bit more complicated than this, but that’s the general idea.) Fluorescents sometimes appear to flicker because alternating current brings that energy to the bulbs in pulses, rather than steadily. In incandescents, the hot filament stays hot—and therefore bright—despite alternations in current; it can’t cool fast enough to dim or flicker.

“The new CFLs pulse faster than their ancestors, so the flickering is less perceptible, but at some level, it’s still there. CFL manufacturers may be right that the new bulbs are an improvement, but there is still something discontinuous, digital, something chillingly one-and-zero about fluorescence, while incandescent lights offer the reassurance of continuity rather than an alternation of being and nothingness.”

Who wants to have a romantic dinner in the dull gloomy light of a CFL? Why do lighting designers of usually choose halogen, incandescent, high-pressure sodium or metal halide for shops, hotels, restaurants etc. when they want to create an attractive environment, and so rarely CFLs?

Most likely because they are well aware of the fact that even the best incandescent-mimicking warm-white CFLs give a dull, non-radiating light which makes colours look pale and dead due to lower colour rendering (CRI 82-85), spiky spectral distribution (lacking parts of the spectrum – check this out for yourself with the back of a CD and see the spectrum broken up into 3 blocks with all the wavelenghts inbetween more or less missing) and lack of radiance and glow.

And that’s not mentioning all those odd coloured ones which still dominate the lower end and some of the high end of the CFL market (according to recent consumer tests).

Lighting designer Gad Giladi, D.E.S.A., M.F.A. FPLDA, explains what happens when wavelenghts are missing:

“Not only are the quantities of light of CFL ‘equivalents’ not equal to those of the planned replaced incandescents but also the quality of the light greatly differs. This is due to the fact that the spectrum of the incandescent is a continuous one, i.e. has energy in all wavelengths of the visible electromagnetic spectrum while the spectrum of the CFLs, like all discharge lamps is a discontinuous one, i.e., depending on the composition of the phosphor coating of the tubes will present a lack of or a deficiency in energy at certain wavelengths of the visible spectrum.

“This characteristic is not immediately visible to the human eye until the emitted light falls on a surface or an object: the energy in each different wavelength corresponds to a colour perceived by the human visual system. If that colour does not exist in the light, its corresponding pigment in materials cannot be perceived by the eye; if the energy in a specific wavelength is deficient, the corresponding pigment in materials will be perceived as dead, washed-out and distorted. (…)

“That means that where colour perception is important, i.e. everywhere the human being lives and spends time, the replacement of incandescents by CFLs is going to inevitably create dull looking spaces, distort colours of architectural finishes (stone, marble, timber, paint, stucco etc.), of furnishings – curtains, carpets, upholstery, furniture finishes, artwork etc.), warp the colour of skin (people are continuously going to look bad/sick in their mirrors as well as in the eyes of their partners).

“Incandescent lamps are close to theoretical ‘point sources’ which allow for the design of precise optical systems around them to direct the light in an accurate manner. This permits the creation of accent lighting, a means to create visual interest and drama in spaces. CFLs are diffuse light sources and no engineering will truly make a diffuse light source into a ‘point-source’. Gone is accent lighting!”

Lighting designers against incandescent ban (for both light quality and environmental reasons):

IALD – International Association of Lighting Designers
IALD Statement

Jeff Miller, President-elect IALD, Director of Pivotal Lighting, statement

PLDA – Professional Lighting Designers’ Association
PLDA Statement

Kevan Shaw Lighting Design
Summary of points against the CFL

Michael Gehring, Principal of KGM Architectural Lighting
Gehring statement

Scott Yu, Principal, Chief Creative Officer of Vode Lighting
Yu statement

Summary:

There are both visible and measurable differences in quality between incandescent light and the light from even best CFLs and LEDs on the market.

Banning a top quality product in favour of a totally different and quality-wise inferior product is like banning wine with the argument that “wine-lovers can just as well drink cider: practically the same thing” because both are mildly alcoholic beverages with a superficial similarity.

FL/CFL light may have its use where lamps are left on all day and quantity matters more than quality, e.g. at work, in public building corridors etc, but not necessarily in retail, hospitality and domestic environments where consumers expect a more attractive and/or relaxing light.

Light is like air, food and water – it’s essential to our well-being, and quality matters!

Lighting is also one of the most powerful mood-enhancers, can markedly affect how environments are perceived, as well as both comfort, well-being and health.

For this reason, I’m sure many would be willing to pay a little extra for top quality light just to still have choice.

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