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Most traditional hallway lighting fixtures have replaceable lamps (bulbs). I've been told that with LED sconces that "most" do not have replaceable lamps. For an apartment building that would mean replacing the entire fixture every 5-6 years, assuming a 50,000 hour expected life, since they run 24 hours a day. That doesn't seem acceptable.

  • So just put LED bulbs in regular fixtures. – mbeckish Aug 31 '17 at 17:04
  • It's true, many of them don't use bulbs, and therefore are not trivial to replace, the benefit is that lights of different shapes/sizes can be produced, the down-side is that you can't easily swap out just the LED. – Hart CO Aug 31 '17 at 17:12
  • Why not put them on light sensors so they shut off when covered by ambient light? Or if in utility areas, motion sensors. Of course those sensors may prove higher maintenance than the LEDs... – Harper - Reinstate Monica Aug 31 '17 at 20:12
  • Hard to say what most fixtures have, especially without knowing where you are in the world. – mmathis Sep 8 '17 at 15:33
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Time for math! I love math.

50,000 hours x 25W x $0.12/kWh = $150 total running costs over the lifetime of the LED fixture. Plus the cost of the unit itself - say another $150. That's $300/fixture, or $60/fixture-year.

By contrast, a halogen bulb costs $2.50 and lasts 1000 hours. So you need to buy 50 of them to meet the lifetime of the LED bulb. That's $125 in bulbs. Plus running costs: 50,000 hours x 72W x $0.12/kWh = $432 in electricity. Neglecting the cost of the fixture, as it doesn't get replaced, you're spending $111.40/fixture-year for something that has the benefit of being replaceable.

A CFL equivalent might be $4.50, so it's more expensive than the halogen, but it also lasts longer (10,000 hours-ish). It also uses less power than the halogen, but more than the LED. Using the same math, you'll spend $45 in bulbs and $132 in electricity, for an average of $35.40/fixture-year. So if you're going to go replaceable bulbs, definitely go CFL (but then you have to live with the light of CFLs, which some find objectionable).

TL; DR: Even replacing the fixture every 5 years, LEDs are cheaper in the long run than halogens. CFLs are even cheaper than LEDs (slightly less efficient, but cheaper bulbs), but their light is objectionable to some.

  • Halogens seem an odd choice for comparison, also they last ~2000 hours, did you mean standard incandescent bulbs? – Hart CO Aug 31 '17 at 18:22
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    You neglected the labor cost of replacing all those bulbs, and the inconvenience of having it be dark while they are burnt out (as opposed to 70% brightness, the "end of life" criteria for most LED devices - they do not so much burn out as get dimmer, and they will continue operating dimmer for quite some time.... – Ecnerwal Aug 31 '17 at 18:23
  • @Ecnerwal aren't those points in favor of the LEDs? I guess that would be icing on the cake that is LED fixtures. Halogen would be the closest thing to "incandescent" you can expect to find most places. I got lifetime estimates [here] (tomsguide.com/us/light-bulb-guide,review-1986.html). Those are manufacturer lifetimes, though, and so they'd probably be shorter overall if used 24/7. – Chris M. Aug 31 '17 at 20:34
  • Its not the LEDS that will burn out, it is everything but. There is a circuit board, voltage regulators, electronic components, solder joints, and, and, and. The rated hours for the LEDs is like giving a rated hours for a screw on a HDD, the screw will outlast that rest of the components so whats the point? Our 2 light enclosed ceiling fixtures destroy LED bulbs, way more than CFLs of Incandescents. Even using name brand (but on sale) LED bulbs because they get too hot inside the fixture. – Damon Sep 11 '17 at 10:34
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I get it. A light emitter is a "bulb" which frequently burns out, and the fixture is a durable thing which does not. That's been the paradigm, and now it's dead. Buh-bye.

LED is an extremely long-lived technology - so long that in a fixture, the LED emitter life is not the limiting factor. Probably the #1 threat is electronic driver failure, particularly capacitors, then solder crystallization over years, corrosion from weather, physical damage and the like. They talk about old LEDs getting dimmer, I've never actually seen that.

So where do they get 50,000 hours? It's arm-waving guesswork. Because somebody pinned them to the wall and said "You have to say a number, you can't sell this thing without saying a number!" So they made something up. And mostly they are basing that on things like driver failure, solder crystallization, etc. and some have to do with absolute fixture life, not "powered on" life. So they make assumptions as to your usage, e.g. if they expect failure in 23 years and 25% (6 h/d) usage, they call it 50,000 hours.

Fully expect that at hour 50,000, 5% of them will have failed, and at hour 100,000, another 10% will have failed. And if you take them to a rework bench and replace some caps and reflow the solder or whatever, most could be brought back to life for another 50,000 hours.

I don't want to hear about life-cycle cost considerations if they involve cheap fixtures gotten from Home Depot. If life-cycle is a genuine consideration, shop wisely for fixtures with excellent build quality and make some careful decisions about cost of servicing vs cost of quality. Hey, Google built their empire on cheap, unreliable servers, and robust software that dispatched around hardware failure. The numbers may say that's the way to go.

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Many fixtures that call themselves "LED fixtures" do in fact have hardwired LEDs, and if they burn out, you have to replace the entire fixture. Some of these have designs that are 'novel' and could not possibly be done with regular bulbs, others seem to be simply trying to use "LED fixture" as their selling point.

If you're concerned about maintenance and longevity, just install a regular fixture and put LED bulbs in it. There are LED bulbs of literally every type on the market. To be safe, stick with a fixture that supports one of the common size bulbs: A19 (probably what you think of when someone says "light bulb"), MR16 or GU10. If you want a brighter bulb, many "100W-equivalent" LED bulbs are A21 (which is slightly larger than A19).

  • In my market (USA), the most abundant and cheap bases are Edison (E26) and Candelabra. I have great variety in those, at the lowest prices. Others tend to be much more expensive. – Harper - Reinstate Monica Aug 31 '17 at 21:27

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