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Saturday, October 12, 2013

LED bulbs

I've recently been buying LED lightbulbs to replace the various bulbs we usually use around here. For a while, my wife was buying CFL bulbs, but she got tired of them, not so much for the quality of the light, but for the fact that their odd shapes and sizes kept them from fitting where she wanted them. So she's been buying the energy-efficient incandescents instead. These use a small amount of halogen (usually flourine or bromine) inside the bulbs, resulting in a chemical reaction which redeposits the tungsten evaporated by the bulb onto the filament, which allows the bulb to be operated at a higher temperature, where it has better efficiency. Most of which I learned from the Wikipedia entry.

The halogen incandescents are only very slightly more efficient than regular incandescents, though, and the GE ones, at least, are also dimmer than the bulbs they're supposed to replace. The 60 W replacements consume 43 W to produce 750 lumens rather than the standard 800 lumens, while the 100 W replacements consume 72 W to produce 1490 lumens rather than the standard 1600 lumens. Meanwhile, I can buy LED light bulbs that consume 9.5 W and produce 850 lumens, or 19 W and produce 1680 lumens. In math terms, they consume a quarter of the power and produce about 15% more light than the energy efficient incandescents.

I've long believed that LEDs were probably the light bulb of the future. They're more efficient than incandescents or CFLs, and last longer--twenty years, by standard measurements (which, unfortunately, don't actually involve waiting twenty years and seeing if they still work).

The problem is that LEDs cost commensurately more. I can buy decent quality 60 W equivalent LED bulbs for $10-20 apiece, or spend $2.50 for an energy efficient incandescent. And as for 100 W bulbs--not that long ago, you couldn't buy 100 W equivalent LED bulbs at any price. That's changed, but they're still expensive: $50 or more usually, though I have found a few available for $30 apiece. 100 W energy efficient incandescents? About $2.50 each for those too. Sure, the LEDs also have a 20 year lifespan, compared to the one year of the incandescents, but then again, LED prices are coming down pretty quickly, so buying incandescents this year and buying LEDs a year from now would probably save money in hardware costs. Not, though, when combined with electricity costs. So my compromise is to replace the bulbs we use the most--kitchen, living room, bedroom, with LEDs, and leave the rest for a little while.

LEDs in the living room's candelabra
One of the problems I've run into doing that is that a lot of pre-existing light fixtures in our apartment use the candelabra bulbs, and finding LEDs for those is more difficult--escpecially since it takes a lot more of them to fill the light fixture (6, in the case of the two we have in the living room and dining room), and they're about the same price as 60 W bulbs. Fortunately, I have found a fairly cheap option from Feit--a three bulb pack for $21. These actually work pretty well. They have a slightly higher color temperature at 3000 K (which means they're slightly more white than the yellowish incandescents), but they are close enough for us. We get 300 lumen for 4.8 Watts out of them. I have noticed that they turn on a bit slower--most of them seem to take half-a-second to come to life after flicking on the switch, which is usually something you see in CFLs, not LEDs. And one of the sockets won't work for any of the Feit LEDs for some reason--I had to use a LED from another company (one of the ones costing $10-20). But it works. And it seems to be just as bright as the fixture in the dining room, where I'm still using all (non high efficiency) incandescents.

The incandescents in the dining room.
In the kitchen, we have a five light fixture which takes normal sized 60 W bulbs. Two of them have CFLs which my wife put in a while ago, and since they seem to be working well, I haven't bothered replacing them. The rest I've replaced with LEDs, all from the Cree 60 W replacements. These have the right size, even if they're a bit oddly shaped.
The one on the left is the old style Cree 60 W, while the one on the right is the Cree TW 60 W.
I've tried both the older Cree bulb, and the Cree TW, which is supposed to have better color. I think the color of the TW bulb is a bit better, but as it's also more expensive ($18.50 vs. $12.50), and it also consumes more power (13.5 W vs 9.5 W). I think that the older bulb is a better purchase. It can be found at Home Depot, in packs of 6 (or less, for a slightly higher price), though it looks like that may not last for much longer.

I have yet to buy any 100 W bulbs. I bought a 75 W bulb from Sylvania at Amazon, but at $38 it was pretty expensive. Still, it works pretty well, and it appears to be brighter than the 100 W equivalent CFL which it replaced. That may simply be because the light is less omnidirectional, and while it produces only 1100 lumen, more of it is in the direction I want, while the 1600 lumen CFL sends more light up and to the sides.  Or it could just be that I didn't wait long enough for the CFL to reach full brightness--but if it takes more than a couple of seconds, that's an advantage for the LEDs.

100 W equivalent LEDs are mostly above $50, but at $30 apiece, this set of two seems more reasonable. I'm a little bit reluctant to buy them before I see some more reviews. They seem different from the usual orange Philips LEDs, and I'd like to know why. I've also spent a good bit on LEDs recently, and these, while cheaper, are still expensive. They're also larger bulbs, matching the large size A21 bulb, rather than the usual A19. There are places where they can fit, but they're too big for a lot of our fixtures.

I think I'll wait a month or so before buying any more LEDs, and then I'll probably buy more of the Feit candelabra bulbs, the Cree 60 W bulb, and the Philips 100 W bulbs.

Update (10/13/2013): I was clearing out my pictures on Google+, and accidentally deleted the pictures I had here.  I've replaced most of them, but I've changed the text so it's not as dependent.

1 comment:

  1. I have also used LED light fixture in my home instead of incandescent bulbs. I know they are expensive than other lights. but how can I forget that they helps me a lot to save money on electricity bill. I have used them in kitchen, bathroom, in outdoor area, in rooms even in my business also.
    Reference: http://www.adattsi.com/

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