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My kitchen light fixture has three 60 watt bulbs on a dimmer. The dimmer switch has a dim function and a separate switch for on/off. At night I leave the lights at the dimmest level as a night light. It is probably equivalent to 8 or 10 watts per bulb. The bulbs are on 24/7 either on dim or bright. They last about 3 years like that--about 25,000 hours.
I also have a red bulb 15 watt in a night light in my bedroom. On its lowest setting it puts out about 4 watts of light. That bulb has never been changed and runs 24/7 for about 18 years.
Question:
Clearly using bulbs at a lower light level improves the life of the bulb. The filament does not get as hot and there is not hot/cold changes. I am planning on replacing the kitchen bulbs with LEDs. LEDs have a rated life of 25,000 hours and can be dimmed also.
So will the LEDs used as I do in my kitchen fixture have just the rated 25,000 hours (about what I get with incandescent bulbs) or will they similarly get extended life because I am using them mostly in the dimmed condition?
If there is no improved life then using the expensive LED bulbs does not make any sense to me.
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LEDs used close to their rated max current will have lower life. They get dimmer, for one thing. That being said, I have no idea how hard they are running the LEDs in a typical led light bulb. Nowadays, you have to make sure that LED bulbs are dimmable, cheap ones aren't
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I ordered dimables (Cree, daylight) they arrive today. They are rated for 25,000 hours which is approximately what I am getting from the dimmed incandescent bulbs. If they don't get much better life than 25,000 hours then it is a bad investment for me. They cost about 10 times what an incandescent bulb costs.
If they go 6 years instead of 3 years the money does not work but the convenience does. But if they last the same 3 years I will have wasted about $30.00.
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I haven't had good luck with cheap LED's. their life span has been measured in hours or less
I have a bunch of the Cree bulbs that HD sells, and so far only have had one bad one and it was DOA. But haven't had them installed that long (a year for some, a few months for others) either.
Reality is that which, when you stop believing in it, doesn't go away. - Philip K. Dick
Mark
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Same with me and the CREE. They have been working well other than the one that did not light straight out of the packaging. the Borg took it back no questions asked.
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I live in FL and went all LED two years ago. My electric bill reflects it. Not only are they cheaper to run, but they put out less heat so the AC works less. Depending on location, YMMV.
Some of mine are solar and battery powered. So I have lots more light for less $$$. My recommendation is to find a way to make the investment by driving fewer miles or giving up a latte.
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one place I haven't had much luck is replacing standard incandescent bulbs with LED bulbs in outdoor motion activated light fixtures.
Reality is that which, when you stop believing in it, doesn't go away. - Philip K. Dick
Mark
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I have 100 watt equivalent CFLs outdoors; they work fine in the summer, but in the winter I have to leave them on from the time I get home until I retire for the night. Otherwise it takes so long for them to get bright that it doesn't even pay to turn them one. I'd be better off with a flashlight.
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CFLs aren't that great outside, because of what you mentioned. I have some can lights over my carport. in two I have LEDs and the other two CFLs.
Before I spend more money on LEDs for the other cans, I'm waiting to see how they hold up. But these lights aren't motion activated. Its seems like the constant on/off of motion activation is what kills the LEDs I've tried other places.
Reality is that which, when you stop believing in it, doesn't go away. - Philip K. Dick
Mark
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Cooler said:
I ordered dimables (Cree, daylight) they arrive today. They are rated for 25,000 hours which is approximately what I am getting from the dimmed incandescent bulbs. If they don't get much better life than 25,000 hours then it is a bad investment for me. They cost about 10 times what an incandescent bulb costs.
If they go 6 years instead of 3 years the money does not work but the convenience does. But if they last the same 3 years I will have wasted about $30.00.
If your math is correct you could have bought 10 light bulbs to one and for the little inconvience of changing them will outweigh the cost. The savings in the bill is not that noticable when dealing with such low wattage. Good luck though. You are helping the enviroment.
John T.
