A Tale of Two Tests: Why Energy Star LED Light Bulbs Are a Rare Breed 314
cylonlover writes "Just over a week ago Gizmag reported that Philips' 22 W LED light bulb, designed as a like-for-like replacement of a 100-W incandescent light bulb, was the first LED bulb of its type to receive the stamp of approval from Energy Star. But looking at the Energy Star requirements reported by Philips in its press release, it seemed a little strange that Philips' product is the only one to have been certified – given that products long on the market appear, at face value, to meet those requirements. Since then, Gizmag has spoken to LED light bulb makers Switch Lighting and other industry players to find out why they're apparently playing catch-up."
tl;dr: 9 month test required + uniform radial flux (Score:5, Informative)
.
I use "half-sphere" to mean ($2 \times \pi $) steradians [wikipedia.org], and you can pretty much visual what I mean by a half-sphere. So I guess an "A-bulb" has to radiate light almost uniformly over 8/9-ths of that solid angle [wikipedia.org].
.
"Radiant Flux" [wikipedia.org] is the term used to describe the radiant power : the measure of the total power of electromagnetic radiation (including infrared, ultraviolet, and visible light). The power may be the total emitted from a source, or the total landing on a particular surface. So neither "radial flux" nor "radiant flux" makes sense in that article. Wrong units either way. Spatial distribution of radiated light would be measured in steradians.
Re:Still waiting (Score:5, Informative)
To get the Energy Star certification, the bulbs need to have a projected lifetime of 25000 on-hours (where lifetime means the bulb can emit no less than 70% of its rated light output during that time). If there's going to be planned obsolescence, it's going to be from better bulbs replacing them even though they're still working.
Avoid CFL mistakes (Score:4, Informative)
Re:Certifications (Score:5, Informative)
Actually, RoHS is most certainly a scam. The net effect on the environment has been horrible. Rather than the electronics manufacturers engineering in planned obsolecense, the EU did with RoHS.The environmental impact is literally an unmitigated disaster in parts of China. The cost of aerospace grade components has increased substantially (yes, we have an RoHS exemption for aerospace applications; tin whiskers are a stupid cause of death) and we've got a different set of more toxic metals accumulating in the benthic muck and getting "recycled" with 3rd world environmental standards. What a fucking win for the environment.
Re:Avoid CFL mistakes (Score:5, Informative)
Anecdotal evidence is just that. I've used them all through my house and bought different qualities. I find that in general they either stop working in the first two months or keep working through several years. My power supply is very good.
Re:Avoid CFL mistakes (Score:2, Informative)
I've been using the same ones for 11 years, one takes longer to start these days, but none have died. Perhaps they're die when a house has a bad power source?
Yes, you need a pretty clean power supply to get maximum life out of them. And going along with that, the fixture it's placed in needs to not be a complete piece of shit. Also, they have a fairly narrow optimal temperature range compared to an incandescent bulb- running them in very cold environments (such as the one above my porch where the temp drops into the -20(F) range for weeks during the winter) will drastically reduce the lifespan.
I'm all in favor of low-energy consumption, but when you look at the cost of re-wiring houses, rebuilding electric grids, replacing fixtures, installing heating elements for cold-weather areas, etc. the actual energy costs to totally abandon the old-style bulbs far exceed the gains from the LED and CFC's. And that doesn't even start to account for things like asbestos removal and disposal, lead cleanup from old paint and pipes, and other environmental costs associated with replacing wiring and sockets in older buildings.
Re: 9 month test required + uniform radial flux (Score:5, Informative)
The actual Energy Star requirements [energystar.gov] are for "Luminous Intensity Distribution," and call for:
Re:quality? (Score:5, Informative)
But to answer your question...it depends on the LED bulb. Since LED's come in several colors but white isn't one of them LED bulbs make white using a couple of different methods. [wikipedia.org] So there are some LED's that have the same harsh temperature and others that are very close to the warm glow of an incandescent. Philips just announced a new process that will bring near incandescent quality with better efficiency (200 Lumens Per Watt (LPW)) [extremetech.com] than existing LED technology but it is still a few years from production.
Re:like for like replacement wrong (Score:5, Informative)
They haven't. Best Philips I could find, I think, had a CRI around 90; most are in the 80s (where 100 is blackbody for the rated color temp).
I have some Sylvania Par20s with a 95CRI and at full power they are not only as bright as 50W halogen PARs but very, very close to the same color (I think they're 2900K, vs 2800ish for incandescent halogens). Best price I could find was $34/ea, but they're great - and dimmable. At dim, though, they're goofy looking because the light temp doesn't change, but I can live with that. I had one of 13 fail within 2 weeks of installation, and I'm still waiting (3 weeks later) for a replacement.
Re:Why light bulb form factor? (Score:5, Informative)
Because
(1) you don't have to pay an electrician to remove and reinstall a lamp, but you do a fixture
(2) you don't disrupt the flow of business and it takes a shorter time to re-lamp than replace a fixture
(3) if you find that the LED sucks, you can go back to what you know works
(4) In 10 years, when one (or more) of the 30 year life fixtures dies and they don't make that model any more, I can replace a lamp and the fixture will still look the same. If I have to replace a fixture, then I have an oddball looking spot in my ceiling. Not everything is a warehouse where aesthetics mean nothing.
Oh, and there are a good number of older consumer fixtures which either (a) anticipate a certain light pattern or (b) actually use the lamp as the structure to hold the shade. I you think it's hard to convince people to buy a $20 lamp instead of a $1 one, it's even harder to get them to buy a new $60 fixture to put it in.
It's all in the engineering (Score:4, Informative)
There's a consensus of sort that power supplies are often the most underengineered things out there in any electronic device. Well, guess what, in a CFL or a LED the entire electronics are the power supply, there's nothing else. When a CFL fails, it's not because the bulb has failed, it's because the power supply is dead. It's certainly possible to engineer a power supply that will last, but such know-how is rare and expensive, and engineering management often doesn't understand that it takes real effort to make a long-lasting power supply. You have to qualify every single part, pretty much -- there's no such thing as letting the purchasing loose to get the best deal. If you want to make a CFL or a LED lamp that will last as long as the life of the light-emitting element, you need to do proper design, then qualify sample parts, then do extensive testing on prototypes, then purchase a batch of parts for a production run, then re-qualify all of those parts again, then have the boards assembled, then qualify the board assemblies, and only then you ship. That's what it takes to get a quality product out. That's what it takes to get a lamp out that will be so old by the time it gets replaced that the house might have changed owners a bunch of times in the meantime. Guess how it's done in real life on consumer CFL/LED bulbs, LOL.
Re:What about plants (Score:4, Informative)
Yes. Yes.
http://www.ecaa.ntu.edu.tw/weifang/led/Effects%20of%20Frequency%20and%20Duty%20Ratio%20on%20the%20Growth%20of%20Potato%20Plantlets%20In%20Vitro%20Using%20Light-emitting%20Diodes%20--%20Jao%20and%20Fang%2039%20(2)%20375%20--%20HortScience.htm [ntu.edu.tw]
you're missing some factors (Score:4, Informative)
The Philips 22W bulb needs to *replace a standard bulb*. That is, the complete unit including the power supply needs to fit in the space of a regular bulb, and it needs to radiate in a certain pattern. If you're not limited by the standard bulb form factor then a bunch of different options open up.
Also, your comparison with the MK-R are misleading. According to their web page, a single Cree MK-R uses 15W to put out 1800 lumens (which is what the Phillips bulb puts out). Only the 2700K/3000K versions are available in a 90CRI version, and the higher the CRI the lower the lumens/Watt.
Re:Avoid CFL mistakes (Score:4, Informative)
"and the heat output from individual LEDs is so low"
Maybe from your cheap-ass tail-thru LEDs.
You try powering a 1w SMD-LED without any thermal consideration.
You'll be lucky to get 500 hours of operating time out of it. It will slag itself.
Just saying since I'm working with 15w LEDs in a 7mm x 7mm package, and those can slag themselves within a few SECONDS without proper thermal consideration.
The myth of LEDs don't emit heat is bullshit. HPS is about 20% efficient in energy in/light out. LED at the max is 40% in single wavelengths currently.
So the reality is you get a 400w LED, you might emit 25% less heat vs an equivalent power HPS, but you're still dumping more than 200w of heat out into the air/localized fixture.
Speaking as an LED light manufacturer and current leading tester of the MK-R and XP-G2 LEDs from Cree. [youtube.com]
Re:quality? (Score:4, Informative)
The "ugly and harsh light" is described in the industry as Color Temperature. [wikipedia.org] I'm not sure if it is a requirement to include but most bulbs come with a Color Rendering Index (CRI) [wikipedia.org] rating. It's a scale from 0-100 (100 being a reference incandescent bulb) to rate the Color Temperature of a bulb.
CRI doesn't measure color temperature; it's an indirect measure of the fullness of the spectrum given off by the bulb.
Color temperature tells you how reddish or bluish the light is -- does it look more like incandescent light (reddish) or daylight (bluish)?
CRI tells you how well the light given off by the bulb will allow you to see a range of colors. A CRI of 100 means perfect color fidelity. A CRI of under 90 or so and you will notice that some colors don't look right, because the bulb has dark bands in its spectrum. The CRI measuring process takes color temperature into account -- both warm white and cool white bulbs can have similarly high CRI scores.
For an example of extremely poor CRI, see low pressure sodium bulbs that used to be used a security and parking lot lights. Everything illuminated by them -- cars, clothing, faces -- looks either yellow, black, or dark purple.
Re: LED Bulb interference (Score:3, Informative)
I read about that awhile back and forgot it, then a month or so later I installed a couple of LED bulbs in a room of my house close to my TV antenna... and I lost a channel in the VHF band.
Later on I remembered about the LED bulb RF emission problem, and I realized that my TV reception was impacted negatively by the LED bulbs I installed near it. So I moved my antenna and got my channel back.
VHF and UHF TV are not that relevant anymore, but some folks still choose the free option rather than pay for crappy limited expensive options from other providers, so this LED bulb interference could be bad as more people install them.