Do you have first hand proof they are THAT sabotaged............I have 1st hand proof they are great .
Cite me a BOM ( Bill of materials ) for one .
Do you know how much LEDs are as bare * dice* from CREE .
Do you know the cost of the power supply for the LED system .
My PAR spots are from TOSHBA . I have had them on for 2.2 Years . 24/7 .. that is more then 16000 Hours .
The box said 20K plus life . Mine are at more then 3/4 the way to there lable Life and I have Yet to have a problem .
I have never said that they are sabotaged. Merely that they will not last a lifetime. If you like them, then by all means use them. That is the nature of freedom of choice. I will never try to force my belief or choices on you. All I am suggesting that the more complex something is, the more that it costs, both to the end user in cash, and the total material used that have to be produced from limited resources as compared to an incandescent bulb. My main beef is that the light is not as good. Part of full spectrum light is the IR portion. Yes, our eyes cannot 'see' IR, but our skin does and many things in our homes fluoresce both from IR and UV. Those things do not look the same or IMO, as good as when they do and when good old fashioned incandescent lights are used. This is why I do not have 40 watt fluorescent tubes lighting my living room either. The light from those while appropriate for an office cubicle or basement is not for the home interior.
many things in our homes fluoresce both from IR and UV.
No visible light fluoresces from IR. The source that excites fluorescence has to have a shorter wavelength than that of the fluorescence that results. That's just physics.
No visible light fluoresces from IR. The source that excites fluorescence has to have a shorter wavelength than that of the fluorescence that results. That's just physics.
All I know is that things look different under LED / CFL lights. For my eyes, it is not as good as it has a very cold appearance. I am not going to post on this thread anymore, as I am not going to convince anyone of my viewpoint, and no one is going to convince me against my viewpoint. Fortunately, I had the means to prepare for the ban on incandescent bulbs. I have a literal lifetime supply of them save for a piece of space junk landing on my barn. If that be the case, I have contacts in South Asia an East Asia that can supply my fix of incandescent light bulbs. I feel sorry for those folks who do not have them means or contacts to keep decent lighting in their homes. They have been truly wronged in my opinion.
I wish not to be in any flame war, nor to cause ill will. That is against my core Buddhist beliefs. I will be happy to talk about my HexCrawler, the quad Propeller boards that I have just ordered, robotics or Basic Stamps (the neatest thing to be invented since cats), or if anyone is interested via private message about my farm, farm philosophy, practices, etc.
May this new year bring everyone much joy and happiness.
Up-Conversion is a very unusual phenomenon. A counter-intuitive anti-stokes process occurs where the material absorbs lower energy photons and emits higher energy photons as fluorescence. The trick is that up-conversion materials absorb two or more low energy photons and then emit one high energy photon. By definition, up-conversion phosphors must be much less efficient than down-conversion phosphors. Typically, up-conversion phosphors are illuminated with high intensity light sources such as lasers in a controlled (subdued) lighting environment.
So it's very unlikely to be observed in a normal household situation.
Also, bear in mind that there are two kinds of "white" LEDs: those that consist of RGB emitters and those that consist of a blue emitter surrounded by a fluorescent material. The former, because its light consists of three narrow spectral peaks, may not be able to render some colored objects truly. But it does have the capability of having its apparent "color temperature" adjustable. The latter is more broad-spectrum and, potentially, more pleasing to the eye. But its color temperature is fixed by the mixture of fluorescent powders.
I don't get this idea of "colour temperature" when talking about lasers, LEDs, or fluorescent material materials, which emit a few spikes of intensity of this wavelength or that here and there.
Sounds far removed from "black body radiation" where this whole colour temperature idea came from.
What if the thing you want to look at only reflects, or transmits if you are looking though it, wavelength λ1 when your illumination only has λ2, λ3 and λ4?
I don't get this idea of "colour temperature" when talking about lasers, LEDs, or fluorescent material materials, which emit a few spikes of intensity of this wavelength or that here and there.
The eye can be fooled by the correct R:G:B ratios into "perceiving" a given color temperature. IOW, pick a blackbody radiation color temperature, see how the eye's cones respond, and adjust the R:G:B to produce the same response.
What if the thing you want to look at only reflects, or transmits if you are looking though it, wavelength λ1 when your illumination only has λ2, λ3 and λ4?
That was the thrust of my comment above, "The former, because its light consists of three narrow spectral peaks, may not be able to render some colored objects truly."
Here's the spectrum of a typical fluorescent-style white LED:
Notice that, other than the blue primary peak, the fluorescence is very broadband, without any spiky peaks at all.
and now get to make the same number of light sources that cost the consumer anywhere from 15 to 60 dollars apiece. As I said before, follow the money, and there you will find the truth.
I always wondered what LEDS stood for, now I know, Lighting Expensive Design Scam
You know, from what I've been reading I don't think incandescent bulls were actually banned in the U.S. I find all the rules and such kind of confusing, but it seems the government just mandated that certain bulbs (those most commonly used in the home) have to produce a minimum amount of Lumens per watt. Apparently the manufacturers decided incandescent types would never be good enough and went looking elsewhere. I did read that G.E. had made an incandescent that met the specification, but I never followed up to see if that was correct.
All I know is that things look different under LED / CFL lights. For my eyes, it is not as good as it has a very cold appearance.
LED bulbs come in a variety of color temperatures. The "Soft White" Cree 60 watt equivalent bulbs produce light that is indistinguishable from regular filament bulbs. Home Depot is selling these for $5.97 right now normally $12.97.
It is the exact same bulb that you can buy from some FIRST teams as a fund raising device. I have a case of them in my office. The two cons most often brought up in reviews are buzzing when dimmed and a dark spot in the center of the bulb. The dark spot is indeed there but it has zero effect on the light pattern that the bulb casts, it is only apparent when looking straight at the bulb. As for the buzzing when installed on a dimmer circuit, I could hear nothing even when standing on a chair with my ear a few inches from the dimmed bulb. It may be an issue with certain types of dimmer switches. Mine is very old, nothing special about it.
However, I actually prefer the "Daylight" color temperature. Too bad these are not available through the FIRST program.
Regarding the loss of heat, and having to make that up... I do not feel too bad leaving lights on in the winter since they do help heat the house. It would be better though to use less electricity for lighting and make up for the lost heat using a more efficient heating system such as gas or a heat pump. Many lights fixtures are stuck to the ceiling so most of the heat they create probably benefits the attic more than the living space.
Well my desktop is a 64 bit Quad, Intel Core 2 with a 350 watt power supply and 3 hard disks inside. The monitor is a Benq that is rated at 1.5 amps for 100-240VAC.
Yes, the PSU may be rated at 350W (sounds wimpy. Gaming and high-end workstations tends to have 600 - 750W PSUs), but...
That doesn't mean that the computer actually draws that much power.
The PSU is sized to cover 'peak usage' by the stuff inside the PC, and really, unless you have a really hefty Gaming graphics card(if so, that 350W won't be enough anyway), that happens only at boot.
The 1.5A rating of the PSU on that monitor is at the lower end of the voltage rating, ie. at 100V AC, and even then it's 'with a bit of extra' added in.
Feel free to hook up a cheap 'usage meter' that shows in real-time the power used.
The laptop power rating may be excluding the charge cycle power consumption. I have read claims that they use 200% of the power as desktops.
Nope, the rating is what the PSU is capable of delivering. And no again, laptops are nowhere near a desktop in usage.
Unless the 'deskop' is a HP dc8000 Ultra Slim Desktop or similar and the laptop is a 17" 'draggable' CAD machine with 2 x 512GB HDDs (RAID1) and 32GB RAM...
Some Laptops won't power up if the battery isn't installed, or will tend to crash...
This is because the PSU inside those laptops will draw either directly from the battery, or will pull some from the battery whenever the demand is higher than what the external PSU can deliver.
(When spinning up HDDs during boot for example)
but these spikes are short, seconds at most.
Some get it, Some don't.
'
Hybrid cars are a classic example.
'
"It runs for fifty miles on a single charge"..."You just plug it in and viola, Its ready to go again in a few hours...no gas needed"
'
Better look at your Power Bill...It's not free Power.
'
There is more CO2 spent/emitted on mining Lithium and making the battery's then the car would burn on gas over 10 years.
There is more CO2 spent/emitted on mining Lithium and making the battery's then the car would burn on gas over 10 years.
That is the kind of statement I was fishing for with respect to LED/CFL replacing filament lamps. If only because it feels unlikely that making a big and complicated thing out of exotic materials can ever be more environmentally friendly than spinning a filament. No such statements have been coming forward, only personal/political bias.
However. This is the WEB and you can't just make a statement like that without linking to some kind of article that demonstrates that it might possibly be true.
A similar argument could be made against incandescent lamps. The tungsten used in filaments is a rare element. Most of it comes from China, whose environmental standards are not exactly pristine. Some of it comes from Africa, where it's considered a "conflict mineral." So pick your poison.
Note: If you don't want to read all of this, here is the key point. If a CFL bulb lasts for longer than 50hrs, then the total life cycle energy consumption of the CFL will be lower than that of an incandescent bulb even though they are more complicated to make. http://www.thewatt.com/node/175
' These numbers account for the life of the bulb though, not the entire life cycle of the bulb. The question of whether we can be more lighting efficient by using compact fluorescent bulbs needs an in depth analysis of how much energy is required to make and recycle the bulb. It’s actually quite complex. Here’s why.
When evaluating energy consumption or CO2 emissions of a technology, the full lifecycle of the product should be considered, not just its lifetime productivity. A proper analysis should include the CO2 emissions or embodied energy associated with all of the raw materials, all of the transportation and distribution, the operation and finally the recycling or decommissioning of the product. You’ll find a couple different names for this type of assessment popping up: energy return on energy invested (EROI), well-to-wheel (these two are typically used for fuels), dust-to-dust, cradle-to-grave or more correctly, life cycle analysis (LCA).
When evaluating energy consumption or CO2 emissions of a technology, the full lifecycle of the product should be considered, not just its lifetime productivity.
Exactly what I came to find with my research in Iowa . LEDs are Still better over all from "cradle to the grave "
CFLs are very close but have that nasty power factor issue .
Yes, the USA as well. That is what inspired this thread. I read somewhere that most Americans did not know what was about to happen.
I was in that boat. I stopped listening to the radio and TV years ago. Your thread caused me to do a little investigation. Long story short, the same stores will continue to sell incandescent bulbs. Only two things change: 1) The wattages go down by about 28% for the same lumen output and 2) the prices go up. Inside the large outer envelope of the new light is a small halogen bulb.
I haven't purchased an incandescent bulb in years, so I didn't know the change had already taken place on 100W bulbs.
Bottom line is that incandescent bulbs are going away. Stock up now, use them as long as you can, further discussion will have no affect.
As with any new infrastructure, the transition bears some cost and takes some time, but LEDs deliver MUCH more light per power than incandescent, and we are switching like it or not. The following may apply:
The light industry isn't going to change, just because they go to a different product.
You could have life-time incadescent bulbs. What you do is buy 240VAC bulbs and use them in 120VAC mains. They will likely outlive you.
If you are worried about the disappearance of the incadescent bulbs, but the 240VAC now and stop worrying. If you are in a 240VAC country, get 480VAC bulbs.
Of course, if you just go to the supermarket and buy 120VAC bulbs for 120VAC use, you will have to frequently replace them. It is just like all the other consumer stuff that we have to frequently replace. The offer of life-time LEDs is just a come on to get people to shift over to higher prices for a new format.
Saving money? Bah, humbung! Saving energy? not as much as other things might (like running your A/C at 80 degrees instead of 68 degrees).
The "Soft White" Cree 60 watt equivalent bulbs produce light that is indistinguishable from regular filament bulbs. Home Depot is selling these for $5.97 right now normally $12.97.
These are the bulbs I've been buying and I really like them. They have the same warm, cozy color as regular incandescents. I don't have any on a dimmer, so I can't comment on that. The dark spot is on the very top of the bulb, unless you have one installed horizontally or upside down, you'll never notice it.
I'm heading to the local Home Depot today, if they have them for $5.97 I'm buying a dozen more.
I sure hope the LED lights last longer than CFLs. I've replaced a LOT of those spiral CFLs that were supposed to last for 10X longer than they did. Never got any ROI from those, just co$t.
I've only bought 2 CFL bulbs, the first lasted 7 years in a fully enclosed ceiling fixture, the second is it's replacement.
I have a small table lamp in the living room which serves mainly as a night light. I always put 15 watt G.E. bulbs in it and for some reason they never last more than 3 or 4 months (it's normally on 24/7). I bought a Philips 10 watt equivalent LED bulb (on close out for $8) almost a year ago, put it in that lamp, and it's still going strong. Considering what they charge for those little 15 watt incandescent bulbs, I'm probably already ahead cost-wise.
I sure hope the LED lights last longer than CFLs. I've replaced a LOT of those spiral CFLs that were supposed to last for 10X longer than they did. Never got any ROI from those, just co$t.
The Joule Thief guys say the CFL spiral bulb generally does NOT fail, it's the electrronics that go bad because they cook themselves. So they harvest the CFL bulb and run it off of a single 1.5 AA battery. All night.
I have $h1t load of dead CFL's to use, its about time I learned about inductors and boot circuits.
---
So far the CREE LED looks the most similar to the color of incandescent, I seldom stare directly into light bulbs these days, so the "dark spot" has not noticeable affect. On the other hand, the violet laser point makes the CREE element glow orange/red, which is kind of cool.
Even incandescents are more brown than the sun's yellow; I think people that prefer incandescent do so simple because they are used to it, but the color isn't necessarily "good". RGB LEDs are MUCH cooler looking, we can get almost any color we want. Sure you have to switch to safe electrical voltage and power levels, but what's the harm in that?
Where did you get that figure? Can you point to a reliable reference? My house was built in 1949 and is not considered old by local standards. In fact, a few years ago, I invested in a new "50-year" roof.
-Phil
Well it is essentially why mortgages are 30 years or less. Not all people keep their homes in pristine condition and the normal life of a composition shingle roof is 15 years. That 50 year warranty seems a bit suspect as you and your heirs may never collect on it... either everyone will have forgotten about it, or the company that provided it will be long gone (I do wonder what the average life of a company offering a life-time warranty is.)
Dry rot, poor construction, neglated maintainance, tornadoes, flooding, hurricane, earthquakes, and wild fires are all lumped into that 40 year life. The average life of a house in rural areas of Malibu might be much less, but they keep building in those hills in spite of landslides and wildfires.
Commercial residential real estate generally places the depreciation of a new rental at 40 years. And you just may note that the quality of the wood and other materials going into houses these days are nowhere near as 1949, with the exception of concrete and steel structural elements.(they have certainly improved).
Kitchens and bathrooms in the average two bedroom, one bath home certainly don't last anywhere near 40 years if a husband, wife, and two kids live there.
So I am saying the 40 year mark is generallly accepted among real estate professionals and financial institutions.
I sure hope the LED lights last longer than CFLs. I've replaced a LOT of those spiral CFLs that were supposed to last for 10X longer than they did. Never got any ROI from those, just co$t.
CFLs and all flourecent tube lights suffer shortened lives from frequent on/off switching. They last their longest if they are left on for long durations, even longer if left off (obviously).
They would be just about the worst light to install inside a refrigerator.
So I am saying the 40 year mark is generallly accepted among real estate professionals and financial institutions.
But you still haven't cited any authoritative references. All I see is supposition on your part. Moreover, saying that the average age of a home in the U.S. is 40 years does not imply that they fall apart after that time. As older houses continue to age, new construction will keep the average lower. Even if zero older homes were demolished, new construction could keep the average age constant. Also, if what you contend were true, we would be seeing demolition work going on in every town every day. It just ain't happening -- except maybe in Detroit, but that's another story.
Comments
Cite me a BOM ( Bill of materials ) for one .
Do you know how much LEDs are as bare * dice* from CREE .
Do you know the cost of the power supply for the LED system .
My PAR spots are from TOSHBA . I have had them on for 2.2 Years . 24/7 .. that is more then 16000 Hours .
The box said 20K plus life . Mine are at more then 3/4 the way to there lable Life and I have Yet to have a problem .
Best,
Joe
-Phil
http://www.maxmax.com/airinks.htm
All I know is that things look different under LED / CFL lights. For my eyes, it is not as good as it has a very cold appearance. I am not going to post on this thread anymore, as I am not going to convince anyone of my viewpoint, and no one is going to convince me against my viewpoint. Fortunately, I had the means to prepare for the ban on incandescent bulbs. I have a literal lifetime supply of them save for a piece of space junk landing on my barn. If that be the case, I have contacts in South Asia an East Asia that can supply my fix of incandescent light bulbs. I feel sorry for those folks who do not have them means or contacts to keep decent lighting in their homes. They have been truly wronged in my opinion.
I wish not to be in any flame war, nor to cause ill will. That is against my core Buddhist beliefs. I will be happy to talk about my HexCrawler, the quad Propeller boards that I have just ordered, robotics or Basic Stamps (the neatest thing to be invented since cats), or if anyone is interested via private message about my farm, farm philosophy, practices, etc.
May this new year bring everyone much joy and happiness.
Best,
Joe
So it's very unlikely to be observed in a normal household situation.
Also, bear in mind that there are two kinds of "white" LEDs: those that consist of RGB emitters and those that consist of a blue emitter surrounded by a fluorescent material. The former, because its light consists of three narrow spectral peaks, may not be able to render some colored objects truly. But it does have the capability of having its apparent "color temperature" adjustable. The latter is more broad-spectrum and, potentially, more pleasing to the eye. But its color temperature is fixed by the mixture of fluorescent powders.
-Phil
Sounds far removed from "black body radiation" where this whole colour temperature idea came from.
What if the thing you want to look at only reflects, or transmits if you are looking though it, wavelength λ1 when your illumination only has λ2, λ3 and λ4?
That was the thrust of my comment above, "The former, because its light consists of three narrow spectral peaks, may not be able to render some colored objects truly."
Here's the spectrum of a typical fluorescent-style white LED:
Notice that, other than the blue primary peak, the fluorescence is very broadband, without any spiky peaks at all.
-Phil
LED bulbs come in a variety of color temperatures. The "Soft White" Cree 60 watt equivalent bulbs produce light that is indistinguishable from regular filament bulbs. Home Depot is selling these for $5.97 right now normally $12.97.
It is the exact same bulb that you can buy from some FIRST teams as a fund raising device. I have a case of them in my office. The two cons most often brought up in reviews are buzzing when dimmed and a dark spot in the center of the bulb. The dark spot is indeed there but it has zero effect on the light pattern that the bulb casts, it is only apparent when looking straight at the bulb. As for the buzzing when installed on a dimmer circuit, I could hear nothing even when standing on a chair with my ear a few inches from the dimmed bulb. It may be an issue with certain types of dimmer switches. Mine is very old, nothing special about it.
However, I actually prefer the "Daylight" color temperature. Too bad these are not available through the FIRST program.
Regarding the loss of heat, and having to make that up... I do not feel too bad leaving lights on in the winter since they do help heat the house. It would be better though to use less electricity for lighting and make up for the lost heat using a more efficient heating system such as gas or a heat pump. Many lights fixtures are stuck to the ceiling so most of the heat they create probably benefits the attic more than the living space.
Yes, the PSU may be rated at 350W (sounds wimpy. Gaming and high-end workstations tends to have 600 - 750W PSUs), but...
That doesn't mean that the computer actually draws that much power.
The PSU is sized to cover 'peak usage' by the stuff inside the PC, and really, unless you have a really hefty Gaming graphics card(if so, that 350W won't be enough anyway), that happens only at boot.
The 1.5A rating of the PSU on that monitor is at the lower end of the voltage rating, ie. at 100V AC, and even then it's 'with a bit of extra' added in.
Feel free to hook up a cheap 'usage meter' that shows in real-time the power used.
Nope, the rating is what the PSU is capable of delivering. And no again, laptops are nowhere near a desktop in usage.
Unless the 'deskop' is a HP dc8000 Ultra Slim Desktop or similar and the laptop is a 17" 'draggable' CAD machine with 2 x 512GB HDDs (RAID1) and 32GB RAM...
http://h18000.www1.hp.com/products/quickspecs/13424_na/13424_na.pdf
(Anyone taking the written exam for their Drivers license here in Norway the last 5 years got to use these, some more than once... )
Some Laptops won't power up if the battery isn't installed, or will tend to crash...
This is because the PSU inside those laptops will draw either directly from the battery, or will pull some from the battery whenever the demand is higher than what the external PSU can deliver.
(When spinning up HDDs during boot for example)
but these spikes are short, seconds at most.
'
Hybrid cars are a classic example.
'
"It runs for fifty miles on a single charge"..."You just plug it in and viola, Its ready to go again in a few hours...no gas needed"
'
Better look at your Power Bill...It's not free Power.
'
There is more CO2 spent/emitted on mining Lithium and making the battery's then the car would burn on gas over 10 years.
However. This is the WEB and you can't just make a statement like that without linking to some kind of article that demonstrates that it might possibly be true.
-Phil
http://www.thewatt.com/node/175
'
These numbers account for the life of the bulb though, not the entire life cycle of the bulb. The question of whether we can be more lighting efficient by using compact fluorescent bulbs needs an in depth analysis of how much energy is required to make and recycle the bulb. It’s actually quite complex. Here’s why.
When evaluating energy consumption or CO2 emissions of a technology, the full lifecycle of the product should be considered, not just its lifetime productivity. A proper analysis should include the CO2 emissions or embodied energy associated with all of the raw materials, all of the transportation and distribution, the operation and finally the recycling or decommissioning of the product. You’ll find a couple different names for this type of assessment popping up: energy return on energy invested (EROI), well-to-wheel (these two are typically used for fuels), dust-to-dust, cradle-to-grave or more correctly, life cycle analysis (LCA).
Exactly what I came to find with my research in Iowa . LEDs are Still better over all from "cradle to the grave "
CFLs are very close but have that nasty power factor issue .
I was in that boat. I stopped listening to the radio and TV years ago. Your thread caused me to do a little investigation. Long story short, the same stores will continue to sell incandescent bulbs. Only two things change: 1) The wattages go down by about 28% for the same lumen output and 2) the prices go up. Inside the large outer envelope of the new light is a small halogen bulb.
I haven't purchased an incandescent bulb in years, so I didn't know the change had already taken place on 100W bulbs.
As with any new infrastructure, the transition bears some cost and takes some time, but LEDs deliver MUCH more light per power than incandescent, and we are switching like it or not. The following may apply:
http://xkcd.com/1289/
You could have life-time incadescent bulbs. What you do is buy 240VAC bulbs and use them in 120VAC mains. They will likely outlive you.
If you are worried about the disappearance of the incadescent bulbs, but the 240VAC now and stop worrying. If you are in a 240VAC country, get 480VAC bulbs.
Of course, if you just go to the supermarket and buy 120VAC bulbs for 120VAC use, you will have to frequently replace them. It is just like all the other consumer stuff that we have to frequently replace. The offer of life-time LEDs is just a come on to get people to shift over to higher prices for a new format.
Saving money? Bah, humbung! Saving energy? not as much as other things might (like running your A/C at 80 degrees instead of 68 degrees).
These are the bulbs I've been buying and I really like them. They have the same warm, cozy color as regular incandescents. I don't have any on a dimmer, so I can't comment on that. The dark spot is on the very top of the bulb, unless you have one installed horizontally or upside down, you'll never notice it.
I'm heading to the local Home Depot today, if they have them for $5.97 I'm buying a dozen more.
I have a small table lamp in the living room which serves mainly as a night light. I always put 15 watt G.E. bulbs in it and for some reason they never last more than 3 or 4 months (it's normally on 24/7). I bought a Philips 10 watt equivalent LED bulb (on close out for $8) almost a year ago, put it in that lamp, and it's still going strong. Considering what they charge for those little 15 watt incandescent bulbs, I'm probably already ahead cost-wise.
The Joule Thief guys say the CFL spiral bulb generally does NOT fail, it's the electrronics that go bad because they cook themselves. So they harvest the CFL bulb and run it off of a single 1.5 AA battery. All night.
http://rimstar.org/science_electronics_projects/joule_thief_power_cfl_with_jeannas_light_circuit.htm
https://www.youtube.com/watch?v=FkLET8MhRbU
I have $h1t load of dead CFL's to use, its about time I learned about inductors and boot circuits.
---
So far the CREE LED looks the most similar to the color of incandescent, I seldom stare directly into light bulbs these days, so the "dark spot" has not noticeable affect. On the other hand, the violet laser point makes the CREE element glow orange/red, which is kind of cool.
Even incandescents are more brown than the sun's yellow; I think people that prefer incandescent do so simple because they are used to it, but the color isn't necessarily "good". RGB LEDs are MUCH cooler looking, we can get almost any color we want. Sure you have to switch to safe electrical voltage and power levels, but what's the harm in that?
Hopefully you did not replace them with more CFL types.
Well, I did. Had a bunch on hand. It will be all LEDs from now on though.
Well it is essentially why mortgages are 30 years or less. Not all people keep their homes in pristine condition and the normal life of a composition shingle roof is 15 years. That 50 year warranty seems a bit suspect as you and your heirs may never collect on it... either everyone will have forgotten about it, or the company that provided it will be long gone (I do wonder what the average life of a company offering a life-time warranty is.)
Dry rot, poor construction, neglated maintainance, tornadoes, flooding, hurricane, earthquakes, and wild fires are all lumped into that 40 year life. The average life of a house in rural areas of Malibu might be much less, but they keep building in those hills in spite of landslides and wildfires.
Commercial residential real estate generally places the depreciation of a new rental at 40 years. And you just may note that the quality of the wood and other materials going into houses these days are nowhere near as 1949, with the exception of concrete and steel structural elements.(they have certainly improved).
Kitchens and bathrooms in the average two bedroom, one bath home certainly don't last anywhere near 40 years if a husband, wife, and two kids live there.
So I am saying the 40 year mark is generallly accepted among real estate professionals and financial institutions.
CFLs and all flourecent tube lights suffer shortened lives from frequent on/off switching. They last their longest if they are left on for long durations, even longer if left off (obviously).
They would be just about the worst light to install inside a refrigerator.
-Phil