LED lightbulbs: not ready for primetime

Posted bymathowie 20 Comments on LED lightbulbs: not ready for primetime

The other day, I mentioned this link to an online store selling LED bulbs. LEDs have long been heralded as the next great thing in decreasing home energy consumption, pulling down a fraction of the energy even efficient compact fluorescents use. Plus, they can last for a decade or more. The only downside is the price.

Except, they completely suck in terms of light.

Now, I remember using early compact fluorescent bulbs ten years ago. They were bulky, expensive, made noise, and cast a weird bluish glow on everything. But they matured to the point where everyone is starting to convert their home fixtures to it. As long as you get them with the right color temp (anything less than 3200K), they’ll look like your normal bulbs but use 1/4 the energy and last much longer.

LED bulbs are about where CFL bulbs were ten years ago. I paid $125 for a variety pack of bulbs from C.Crane and I noticed their main LED bulb page only explained the bulb’s brightness in terms of Lumens, with no equivalent to normal incandescents. CFL bulbs usually say right on them that a 13w bulb will act like a 60watt bulb.

In my short time testing out the variety pack, the most light I could get from the brightest bulb was probably on par with a small nightlight or 25 watt bedside lamp bulb. The color is definitely blue and the light is dim. There’s no way on earth these bulbs are worth running out and spending $30+ per bulb on. What’s weird is that my LED flashlights are very bright on small batteries but these are just terrible on unlimited home power.

Maybe in five years or so the technology will mature, but at the moment, save your money and stick with CFL bulbs instead.

Published by mathowie

I build internet stuff.

20 replies on “LED lightbulbs: not ready for primetime”

  2. I’ve bought a bunch of different kinds, but I’ve liked stuff by Phillips most of all. I guess pay attention to the color temp of the bulb to get a less-blue look.
    Personally, I’ve grown used to the slight blue white light and prefer it for reading (makes the pages higher contrast).

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  3. I think you may have gotten ripped on those bulbs. I’ve seen some super impressive “incandescent replacement” LED bulbs, with light quality that resembles halogen bulbs.
    I’ve even read of a few aquarium hobbyists who’ve created banks of LEDs to use to light their reef aquariums, cutting their energy costs down over 90% (you know the small hydrogen reactor I run above my reef? yeah, probably runs me $100 a month), and reef aquariums need light that mimics the sun, both in intensity, and color spectrum. This article compares the super intense metal halide lights to bank of LEDs and concludes that the LEDs beat the metal halides in all categories.
    I’m not sure lumens is a good measurement with light output either. In the aquarium world, it’s PUR (Photosynthetically Usable Radiation) and that generally translates well to what normal folk would consider “brightness”.

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  5. I think part of the problem with LED bulbs is arranging a large quantity of LEDs in a bulb form factor to combine the light, when the LEDs generally emit light in only one direction.
    This is probably why it’s practical for aquaria, where you can spread the LEDs out over a large rectangular bank rather than a point source. (Metal halide lights, by contrast, are inefficient for aquaria exactly because they are point sources.)
    You should look at the new “cold cathode” compact fluorescents. I just got a couple of these (no affiliation) and they’re nice 8W bulbs to replace an incandescent.
    They’re not too bright – they claim 40W incandescent equivalence, but please note that the incandescent equivalence numbers are almost a load of crap. It’s probably more like a 15W incandescent, but it works nicely in our porch light. The cold cathode fluorescents don’t generate heat and can be used in enclosed fixtures. They also can be used with dimmers.
    (By my calculations, these 8W CCFs are about 3-4x as bright as the brightest LED bulb I can find, but I haven’t tried them so YMMV.)

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  6. Does it really save that much money if you have to spend a lot to purchase the bulbs? I can definitely see the point if they were the same price… but your entire “Lighting” budget is consumed on the price of the bulbs themselves. Unless your an enthusiast ofcourse… like all of use, hehe.

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  9. Sounds like you could obtain both the savings in electricity and the savings in bulb cost, without significantly changing the overall experience, by turning all your lights off. And leaving them off.

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  11. This past Christmas, feeling cutting edge, I opted for Phillips LED tree lights. BIG mistake.
    The lights themselves were actually very bright — TOO bright. They became sharp, powerful knives of light scorching my retinas, causing headaches and etching points of light on my corneas that stayed there for hours.
    The lights were very blue, and they flickered at what I assume was 60hz.
    One could easily imagine the “Christmas of the Future” with this glaring disco ball of a tree in my living room.

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  12. I bought several cheap LED flashlights. Bit mistake. They all died. I know, I shouldn’t have bought cheap ones. But the long-life aspect of LEDs did NOT prove itself in this case.
    I have to stick with the expensive Maglites. Sigh.
    For home: compact florescents.

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  13. We bought a crank flashlight (3 or 1 LED) to replace the battery flashlight that our 2 yr old kept leaving on overnight. No more trips to the dollar store for batteries, and the kids both like to wind it up. I can’t imagine buying another battery flashlight.
    I’ve started to look at crank operated cell phone rechargers, so that in the inevitable case of the next power outage I’ll be able to eke out communications and Internet access a bit longer. No obvious winners there yet.

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  14. I’m guessing photosynthetically usable radiation is a little troublesome in determining how usable a light source is for anything but plants. Chlorophylls have a surprisingly narrow absorption spectrum:
    http://www.biologie.uni-hamburg.de/b-online/e24/3.htm
    A plant uses mostly blue and red light (the ca. 430nm is blue, the ca. 650nm is red). They absorb much less green light (hence the color).
    You and I, on the other hand, are most sensitive to green light (a 5mW 530nm laser pointer actually outputs fewer photons than a 650nm 5mW red laser pointer, since the green photons are higher in energy. 5mW of green looks much brighter, though!).
    The sun emits a lot more greenish light than anything else:
    See, for example, this solar spectrum.
    I don’t really deal with plants, but I’m guessing you can get some very intense plant lights with phosphors, LEDs, etc., that emit more blue and red than you’d like. This would correspond to a great deal of photosynthetically usable light but a light with a distracting color.
    “Color temperature” is problematic, too. An object’s color temperature is defined as its closest counterpart to a blackbody of that temperature (every object above absolute zero emits light; as it gets hotter, the light gets bluer and more intense – you and I emit ca. 100W of infrared light, constantly!) that gives the approximate same color profile (i.e., a relatively cool 2000K candle flame is yellow-orange, a tungsten filament is ca. 3000K, and daylight approaches 6000K – the sun is – mostly – a very hot blackbody emitter).
    Part of the problem is that color temperature is just a shorthand for describing a very hot object (“red hot,” “white hot,” etc., all come from the language of blackbody radiation). Fluorescent bulbs and LEDs are not blackbodies, so color temp isn’t necessarily the best way of characterizing light output.
    Another system (possibly more accurate, but with its own problems), is the “color rendering index” – which is empirical, but well-defined and perhaps more appropriate for non-blackbody light sources. I’m probably about as well-versed in consumer light as the average Joe, so I could very well be off on this part.
    Further complicating the issue is the fact that most people are just used to tungsten filaments – I think they’re nice sometimes, but unpleasantly yellow for reading. The low temperature causes much of their BB radiation to be emitted in the infrared, hence the wasted heat.
    Thanks for trying them out. I have been following LED lamps for awhile. Dan’s Data in Australia (http://www.dansdata.com/) reviews LED lights often.

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  17. There’s a lot more to light than mere wattage will tell you. I’m also skeptical about the full mE/m2 (Micro-Einsteins per square meter) these LEDs are actually capable of. For what it’s worth here’s an example of a company who says that they’ve created an aquarium solution, but I’ve seen little technical data there so far:
    http://clearlyleds.com/Index.htm
    I suppose we’ll just have to wait and see if our future is indeed brighter or not.

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  18. Hmmm… my folks’ house only uses LEDs and they work well. The problem is that you can’t buy the cheap ones and een though they are supposed to work for several years, they sometimes only last six months.

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  19. CFAs still make an unpleasant high frequency noise. They are also bulky and don’t fit every lampshade. They seem to burn out more frequently than the manufacturer claims they should. Stil,’I hope both LEDs and CFAs make progress. There’s no excuse for even a 40W of energy being used Karl

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  20. you guys sound OLD! get with it LED’s are the future. not all LED’s are the same. look for the “super LED” bulbs. they are getting better and cheaper every day. try a search on ebay.

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