Slashdot Mirror
A Tale of Two Tests: Why Energy Star LED Light Bulbs Are a Rare Breed
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: the testing requirements for Energy Star for LED light bulbs require running them for 9 straight months, and one company was out of the gate first and this is the first and only one certified as energy star for its 100-W-equivalent LED light bulb. Other point: light distribution must be uniform radially for " 170 degrees of radial [sic] flux": sounds like just a smidge under a half-sphere of radiant flux which is probably what was really meant. I can't find any definition of or any other usage of the term "radial flux".
.
I use "half-sphere" to mean ($2 \times \pi $) steradians, 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.
.
"Radiant Flux" 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.
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.
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.
The leading cause of death for CFLs is heat. CFLs last their rated lifetime (and often much longer) when they're used in well-ventilated fixtures. They die quickly when they're mounted upside down in fixtures that trap the heat around the base of the bulb.
The actual Energy Star requirements are for "Luminous Intensity Distribution," and call for:
"National Security is the chief cause of national insecurity." - Celine's First Law
The "ugly and harsh light" is described in the industry as Color Temperature. I'm not sure if it is a requirement to include but most bulbs come with a Color Rendering Index (CRI) rating. It's a scale from 0-100 (100 being a reference incandescent bulb) to rate the Color Temperature of a bulb. LED's are harder to quantify using this method however so a new method is in development called Color Quality Scale (CQS). Who knew a simple light bulb could be so complex? I found a really good read at Jason Morrison's web site with cool pictures and everything!
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. 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)) than existing LED technology but it is still a few years from production.
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
Speaking as a horticultural and interior lighting research director.
Now that's a pretty impressive euphemism for a marijuana grower.
Faster! Faster! Faster would be better!