Jeff Duntemann's Contrapositive Diary Rotating Header Image

September 26th, 2014:

Let There Be (Long-Lived) Light!

A recent story on the 113-year old light bulb reminded me that I needed to say something about light bulbs here, as they’ve been a long-running low-level project of mine that’s been so low-level that I keep forgetting to post a report. Money quote: LED bulbs are (finally) ready for prime time. It took awhile, but we’re there. Furthermore, there’s upside in LED technology that should make all things LED-ish even better in five or ten years.

Like a lot of people, I stocked up on incandescents when the Feds outlawed them. I did so because my experience with alternative lightning technologies has been hideous. I was curious about CFLs, and I tried them once they became commonplace. If there are light bulbs in Hell, man, they will be CFLs. Their light quality can only be described as sepulchral. They are never as bright as the package says they are. They don’t reach peak brightness immediately, and sometimes take several minutes to get there. (Good luck trying to pee in the middle of a cold night in a one-CFL powder room.) They have mercury in them (granted, not much) which is released into the environment when they break. Oh, and they remind me of spirochetes or intestinal worms.

Fortunately, they die quickly. I recently replaced a couple that were less than a year old. Some have died in a matter of months. I have incandescents in this house that were installed during construction in 2003 and are still in service. Why some bulbs last so much longer than others has always puzzled me. The Phoebus Cartel was real, and it’s not beyond imagination that keeping the tungsten thin for ostensible cost reasons could cover for deliberately limiting the bulb’s life. Still, this doesn’t explain why I have 11-year-old bulbs in some places, and bulbs that repeatedly die in a couple of months in others.

I have theories. One is that some sockets have center contacts that aren’t quite close enough to the bulb to make a firm connection when the bulb is screwed in. Nothing kills a bulb faster than rattly intermittents in the fixture, especially if thermal expansion and contraction of parts in the fixture cause the intermittents. (This is why bulbs shouldn’t be installed with the power on. The moment when the bulb touches the center contact during screw-in is not one moment, but several.) I have also observed that the bulbs that die quickly tend to be mounted either horizontally or at some odd angle, as in my great room ceiling fixtures that are fifteen feet off the floor. The long-lifers are nearly all mounted vertically, bulb-down. I can see how that might work: The filaments of vertical bulbs experience the same gravity load no matter how far they screw into the fixture. Horizontal or angled bulbs will place their filaments in different gravity load situations depending on the angular position of the bulb in the socket, which in turn depends on the manufacturing details of both the socket and the bulb.

Those atrocious CFLs made me cautious. I bought my first LED bulb only about six months ago, having watched them converge on incandescents in terms of spectral signature for some time. That first one was kind of blue, and it’s now in the pantry ceiling fixture where color doesn’t much matter. We’ve been buying Cree TW (True White) bulbs for a couple of months, and they are so close to 60W incandescents that I’ll be ready to install them in critical places (like the master bathroom over-the-sink fixtures) once the incandescents are gone. The Cree bulbs evidently use neodymium-doped glass to add a notch filter to get the spectral signature closer to incandescents. The sweet spot for color seems to be 2700K, and if you want a swap-in for those evil outlawed cheap light bulbs, 2700K is the number to look for. The lerss expensive Feit LED bulbs are bluer, even at the same Kelvin rating, and serve well in places like the laundry room ceiling.

I’ve just started replacing those angled 65W ceiling floods in our great room vault with 650-lumen Duracell Procell BR30s. They’re just a hair brighter, and at 3000K a hair whiter, than the generic incandescent floods we’ve used for ten years now. Replacing angled bulbs fifteen feet off the floor with a sucker pole is a royal nuisance, so even though the Duracells are $20 each, they use a fraction of the power and supposedly live forever.


The clock’s ticking. I’m skeptical. Yes, Phoebus was real. But in the meantime, you really can get 65 watts’ worth of instant-on light with 10 watts’ worth of electricity, in a color that doesn’t resemble a zombie’s complexion. If any of them die on me, you’ll definitely hear about it.