LED lighting experiences.

[WildCat]

edit: for example, here's a link for a well regarded LED grow light being used at NASA: https://www.facebook.com/media/set/?set=a.169375066457203.42346.151110068283703 On the face of it, it is quite compelling. But, NASA is replacing a few thousand $ of HID lights for $10,0000 worth of LED lights. At my energy rates, it would take 3 years for those LED lights to break even. Plus, this is a chamber specifically designed for high light experiments - they have constraints that a greenhouse doesn't. And, of course, there is no grow data yet, just "hey, we are saving watts and heat". I regard it as interesting, but I'm not going to run out and drop a few thousand K on lights with no real data yet. Given that LED grow lights have been touted since 2008 or so, and we still have no data, color me somewhat skeptical. I have no doubt they have use in very specialized circumstances like NASA experiments, or in law enforcement evasion, but to grow my Hatch chili plants, basil and such? Naw. Not yet.

Here's the ones they're using: http://www.apachetechinc.com/red-and-blue-leds/10-red-blue-leds-at120rb.html

 

[Garrison]

The BBC website reported on a study done on installing LED based lighting in social housing. The results were positive both in terms of energy costs and the reactions of the residents. The people behind the report do advocate some sort of subsidy scheme to speed the take up of LED lighting:

LEDs offer a brighter future, says report

 

[mhaze]

That's true for many emerging technologies. If the sales don't increase because everybody is waiting for the cheaper price, the price won't come down and we all miss out on the better cheaper product and the accompanying energy savings. It's a classic catch-22.

Nope.

Here's a case - LED lighting - where greenhouse lighting is a tiny niche in a huge market, which is dwarfed by the gigantic market that LED will take over. The "greenhouse niche market" will benefit from the general movement irregardless of whether greenhouse owners now buy LED or do not now buy LED>

Here's the ones they're using: http://www.apachetechinc.com/red-and-blue-leds/10-red-blue-leds-at120rb.html

$999 for 156 watts.

Here's the general type of T5 fixture I'm going to use.

About $250 for 240 watts.

http://www.ncwgs.com/lighting_ultragrow_t5.php

 

[mhaze]

Slightly different subject.

LEDs for outdoor landscape lighting.

The old style was floodlights or halide up in trees, with carefully sealed watertight enclosures, about $100 EACH. The new LED is about $250, and is integral light and frame, no replacable bulb.

The old style required in many cases cherry pickers to get a guy up high enough to replace the bulb. The new style doesn't require bulb replacements. Difference in cost $150 per unit x 12 units = $1800

Difference in energy? Old style, say for 12 in a yard, 100 watts each, $1 per night.

The new style? You wonder if it's worth your effort to turn them on or off. As far as the cost, maybe $ 0.20 per day.

Savings in 5 years if you do turn them off is 0.80 x about 1600 days = $1280

Savings in 5 years if you don't turn them off 0.40 x about 1600 days = $640

Cost of renting cherry picker and a guy to replace bulbs $800.

Numbers are approximate. Basically this stuff is totally awesome.

 

[roger]

Yes (to the outdoor lighting), but back to the OP. Those are basically 40watt equivalent bulbs. I don't have a single 40 watt bulb in my house, and can't imagine using one. Let's see, in the room i am in now, I have 17 recessed bulbs, all 100 watts, a hanging light with 4 100 watt bulbs, and a floor lamp with a 50/100/150 bulb in it. I'd be looking at, what, $800 or so to replace them with LEDs? Not that I think there is an LED that can work in recessed ceiling lights and generate the same lumens as 100watt halogen, but let's ignore that. And then have to replace them all if we get a lightning strike?

I'm excited about LEDs, but I can't talk myself into buying any yet.

 

[mhaze]

Yes (to the outdoor lighting), but back to the OP. Those are basically 40watt equivalent bulbs. I don't have a single 40 watt bulb in my house, and can't imagine using one. Let's see, in the room i am in now, I have 17 recessed bulbs, all 100 watts, a hanging light with 4 100 watt bulbs, and a floor lamp with a 50/100/150 bulb in it. I'd be looking at, what, $800 or so to replace them with LEDs? Not that I think there is an LED that can work in recessed ceiling lights and generate the same lumens as 100watt halogen, but let's ignore that. And then have to replace them all if we get a lightning strike?

I'm excited about LEDs, but I can't talk myself into buying any yet.

Good points. There are 65 and 95 watt LED, here they cost around $39 and 49-69 respectively. Yes, I'm using these in recessed ceiling fixtures. I agree they are more expensive, and make economic sense only when...say the fixture is high in a vaulted room and requires a ladder even to reach and replace.

Your point about lightning is a good one. Have not heard it before. Here we've got most all stop lights replaced by LED, and a new police station has it's entire parking lot LED. I haven't heard of sudden failures of large groiups of LED lighting due to lightning, but there are "whole house" lightning transient suppressors available.

 

[excaza]

I do find the "blue" to be annoying as well.

It depends on the bulb you get. There are plenty of LED bulbs available with color temperatures similar to that of incandescents.

 

[excaza]

Here we've got most all stop lights replaced by LED

Hopefully they installed heaters so the lights don't freeze over in the cold

 

[mhaze]

Hopefully they installed heaters so the lights don't freeze over in the cold

Nope. They had to learn about that the hard way.

 

[mhaze]

The BBC website reported on a study done on installing LED based lighting in social housing. The results were positive both in terms of energy costs and the reactions of the residents. The people behind the report do advocate some sort of subsidy scheme to speed the take up of LED lighting:

LEDs offer a brighter future, says report

From the article:

"Some of the comments we had was that the light was fresher, brighter and more like daylight," he said.

"Generally, the feedback was that the lighting make it a nicer place to live."

The brighter light levels also had a positive impact on people's sense of security, he observed.

"We also did fit some lighting in external area, such as balcony areas and car parks.

"People also did comment and did make the areas outside feel like a safer environment because it was better lit.

"That also applied to stairwells as well which could be perceived to be an area where shadowy figures like to hang out."​

I like this because it emphasizes not just the energy savings of the bulbs, but peoples' attitudes, feelings and opinions. By contrast Bulb Truthers posting on this forum emphasize energy savings, compliance with law, a duck and dodge type misdirection on the issue of "the ban", various moral and ethical "imperatives", a "we know better than you what light bulbs you should use" attitude, coupled with several ignorance of the engineering and technology of lighting, along with an almost total disdain for individual choice.

 

[roger]

Your point about lightning is a good one. Have not heard it before. Here we've got most all stop lights replaced by LED, and a new police station has it's entire parking lot LED. I haven't heard of sudden failures of large groiups of LED lighting due to lightning, but there are "whole house" lightning transient suppressors available.

I may be wrong about the voltage spikes - it's what I've read when googling around, but it could be bull. My broader point is that I'm willing to let others be the guinea pig while we figure out the real performance of these. For example, the touted 50KHr life? Well, that is just an estimate of when the LED will lose 30% of it's brightness and be replaced. It is NOT a estimate of the MTTF, nor does it factor in the lifetime of the electronics in the base. It's purely "this bulb will get dimmer on this time schedule". Yet people are running around doing energy savings calculations on a 50,000-100,000hr schedule. Google LED lights, and read how many complaints of failure in just a few months there are. And how hard it is to get a company to honor the warranty. It doesn't take many of those events to turn your 3 year payback into a 10 year payback to a never payback.

I've got some outdoor lights that are extremely hard to reach. OTOH, I have lived here for over 3 years, the bulbs were here when I moved in, and they are still working. I guess if I had to hire somebody at $50 to come and replace the bulbs I might spring $40 for a LED. But, I'm not finding $40 equivalent bulbs. The 40 dollar ones are running 800 lumens or so - less than a 60 watt bulb, and I need light. The higher output lights are in square, specialized enclosures in the $500 range. Figure $700 after installation and taxes (I can do my own wiring, but many cannot/will not). Great for a business replacing HPS (depreciation writeoffs, not paying for scissors lift & employee, etc), but once again not ready for residential use, at least for me. Get price down to incandescent or CFL level and it's a no brainer. It'll come in time. In the meantime I'll stick with halogen (my preferred color light) for residential, florescent for the shop/basement areas, and MH/HPS/CMH for plants. And wait for people like Ben to report in a year or two on how it's going.

 

[varwoche]

Got reference?

The links offered previously and herein seem to suggest otherwise:

Thanks -- I'm still taking this information in. In the meantime, it appears that some of these sources aren't so clear in the final analysis. (I'll be more specific later.)

Also, according to the LED vendors, the second generation products are greatly improved. I don't know the extent to which this is true, but the links you provided deal with the older technology.

Other factors to consider as part of the cost equation: (1) LED doesn't get dimmer over time (2) they last ridiculously long and (3) less ventilation required due to less heat.

 

[Trakar]

Thanks -- I'm still taking this information in. In the meantime, it appears that some of these sources aren't so clear in the final analysis. (I'll be more specific later.)

Also, according to the LED vendors, the second generation products are greatly improved. I don't know the extent to which this is true, but the links you provided deal with the older technology.

Other factors to consider as part of the cost equation: (1) LED doesn't get dimmer over time (2) they last ridiculously long and (3) less ventilation required due to less heat.

All valid and accurate considerations to my perspective. The technology is quickly evolving. To my understandings there is some fall off over time, the 50,000 hour replacement time generally isn't a time to failure, but rather the time when light production drops significantly below 80%. Additionally there are some color change issues, especially with the UV LEDs that depend on the phospor coating to produce white light, seems the UV exposure gradually clouds and tints the plastic lens material over time, shifting the color character. The prices have been dropping dramatically over the last few years. By the time I am ready to make major swap outs from CFLs, the price should be quite reasonable and the technology relatively more mature.

edit- Ooops I see that Roger above already made many of the same points.

 

[roger]

Other factors to consider as part of the cost equation: (1) LED doesn't get dimmer over time (2) they last ridiculously long and (3) less ventilation required due to less heat.

1) yes, they do.
2) unproven. Quoted long lifespan is based solely on how long before they dim to unacceptable use. Consumers are reporting quite short lifespans due to electronics failure and heat (see 3).
3) They are very susceptible to heat damage - they are finned to radiate heat, and high wattage bulbs cannot be placed in recessed ceiling fixtures (you are limited to around 60 watts equivalent) Perhaps you are talking about hydro, in which case, yes, if you are growing in a closet to avoid law enforcement you probably have heat issues with HID. But for consumer use ventilation is a huge concern.

 

[Trakar]

1) yes, they do.
2) unproven. Quoted long lifespan is based solely on how long before they dim to unacceptable use. Consumers are reporting quite short lifespans due to electronics failure and heat (see 3).
3) They are very susceptible to heat damage - they are finned to radiate heat, and high wattage bulbs cannot be placed in recessed ceiling fixtures (you are limited to around 60 watts equivalent) Perhaps you are talking about hydro, in which case, yes, if you are growing in a closet to avoid law enforcement you probably have heat issues with HID. But for consumer use ventilation is a huge concern.

The heating is much less with LEDs than incandescent, this isn't to say that some of the cheaper initial knock-offs of first gen bulbs quickly pumped out to take advantage of $70-$90+ a bulb prices several years ago, may have suffered from poor manufacturing quality control but that's why they quickly appeared for sale at a discount when overall LED lighting prices began falling due to the growth of the manufacturing industry and later advances in technology started shaping the market.

 

[roger]

The heating is much less with LEDs than incandescent, this isn't to say that some of the cheaper initial knock-offs of first gen bulbs quickly pumped out to take advantage of $70-$90+ a bulb prices several years ago, may have suffered from poor manufacturing quality control but that's why they quickly appeared for sale at a discount when overall LED lighting prices began falling due to the growth of the manufacturing industry and later advances in technology started shaping the market.

I was responding to the claim about not needing ventilation. The opposite is true. While LEDs do not put much heat out compared to other light sources, they are far more sensitive to that heat, and heat dissipation is a huge concern if you don't want premature failure. Stick that $40 bulb in a recessed ceiling? Don't plan on it lasting for long.

As for reliability vs cheapness, sure, cheap imports won't last long. OTOH, we have plenty of reports, and I have seen, LED traffic lights going out. The claims of 50,000 hours are entirely specious - all that number means is that it takes 50,000 hours to go to 70% of light output due to dimming. It says nothing about the MTTF of the bulb, of the electronics, of damage and color shifts of the lens, etc.

The reality is that these things are failing. Bulbs like the new Philips AmbiantLEDs are getting rave reviews without reports of failure, but they are still new. We'll see where we stand in 5-10 years.

 

[The Central Scrutinizer]

I was responding to the claim about not needing ventilation. The opposite is true. While LEDs do not put much heat out compared to other light sources, they are far more sensitive to that heat, and heat dissipation is a huge concern if you don't want premature failure. Stick that $40 bulb in a recessed ceiling? Don't plan on it lasting for long.

As for reliability vs cheapness, sure, cheap imports won't last long. OTOH, we have plenty of reports, and I have seen, LED traffic lights going out. The claims of 50,000 hours are entirely specious - all that number means is that it takes 50,000 hours to go to 70% of light output due to dimming. It says nothing about the MTTF of the bulb, of the electronics, of damage and color shifts of the lens, etc.

The reality is that these things are failing. Bulbs like the new Philips AmbiantLEDs are getting rave reviews without reports of failure, but they are still new. We'll see where we stand in 5-10 years.

Why do you hate the Earth?

 

[Furcifer]

1) yes, they do.

That's correct. They don't fail catastrophically, they slowly dim (probably less than your own vision dims over the same amount of time )

2) unproven. Quoted long lifespan is based solely on how long before they dim to unacceptable use. Consumers are reporting quite short lifespans due to electronics failure and heat (see 3).

No it's proven: http://www.cree.com/products/pdf/XLampXR-E_lumen_maintenance.pdf

I think you're confusing old LED's with the new ones.

3) They are very susceptible to heat damage - they are finned to radiate heat, and high wattage bulbs cannot be placed in recessed ceiling fixtures (you are limited to around 60 watts equivalent) Perhaps you are talking about hydro, in which case, yes, if you are growing in a closet to avoid law enforcement you probably have heat issues with HID. But for consumer use ventilation is a huge concern.

Very would be a bit of a mischaracterization, especially considering it's about the only thing they're susceptible to (I have underwater LED strips)

Your general observation seems valid in the sense you can't really "cheat" and put a 200watt LED equivalent in a fixture rated for 60watts.

 

[roger]

No it's proven: http://www.cree.com/products/pdf/XLampXR-E_lumen_maintenance.pdf

I think you're confusing old LED's with the new ones.

That link is a test for individual elements, not the performance of consumer bulbs.
http://bits.blogs.nytimes.com/2009/02/11/how-long-did-you-say-that-bulb-will-last/

I'm not talking about "cheating" with ceiling cans. Most of the LED bulbs specifically state they are for open use only. The ones that are for use in cans are limited to 60watt equivalent, whereas I currently have 100watt halogen in them. That's not 'cheating', that's less light. Furthermore, manufacturers actually recommend derating the can and putting less than the rated value for the can (for example). And I haven't even addressed the common complaint with the LED floods - that they don't flood, but act like spotlights.

Here's a 10 watt bulb, as recommened by the FAQ I linked to above for use in recessed cans. 340 lumens. That's about a 30 watt equiv. I'm not putting spotlight, 30 watt equiv bulbs in my ceiling, to replace my 100watt halogens, at over $50 a pop (I have 17 cans to fill in this room alone), and calling it a wash.

LED lights are exciting. They just aren't ready for average home use.


edit: for example, what does Philips say about bulb life? Just about nothing. They have test data for a few LEDs in an automotive application, soldered to a board here: http://www.philipslumileds.com/support/documentation/reliability-data, which has no bearing on consumer light bulbs in average situations. For those, they talk about lumens maintainance (how long they take to dim due to age): http://www.philipslumileds.com/technology/lumenmaintenance

Claims of 25,000 to 50,000 hours are a shell game - they (generic they, not Philips specifically) compare the 1000 hours of incandescents (which is a true MTTF #) to hours to dim to 70%. It's a meaningless comparison. I'll credit I have no data either, so maybe the MTTF for a consumer LED bulb is half a million hours! But, given the shell games being played, I strongly suspect that is not true. Suspicion is further aroused when I look at the terms of the warranty: you have to send back the bulb, the receipt, and the frigging box. The harder you make it, the less you are really standing behind your product. Especially since these are supposed to last 10-20 years - at which time it should cost a few dimes for the company to replace. In comparison, I can take a 10 year old Patagonia goretex shell to any Patagonia store, without a receipt, with obvious abuse, and have it exchanged no questions asked. That's a company that believes that their product will last the time period they claim it will. (that's an apples/orange comparison, but why are they making it so hard to return?)

 

[mhaze]

Most of the LEDs I am buying do not promise 50K hours. Typically they say 10K hours, sometimes 20K. Being an "early adopter" I have a group of 8 installed since 2006. One has failed, the others are somewhat more yellow than when installed. That's running non stop for 5 years, incidentally, because that group, we don't bother to turn off.

RE heat accumulatation and dissipation: The solid state control circuit in an LED needs only to produce low voltage DC, while that in a CFL is considerably more complex. The same issues you mention are more true with CFLs. But no one ever mentions that, do they?

RE flood vs spot - yes, both varieties are available. Often the package will state the beam dispersion. Yes, a year or two ago there was less variety.