# 100 year light bulb?

1. Jan 9, 2005

### Ivan Seeking

Staff Emeritus
True or false?

2. Jan 9, 2005

### polyb

I dont know Ivan. I tried finding it on the Guinness Book of World Records site but was unable to bring anything up in the search. I did find this at the Christian Science Monitor though:

http://www.csmonitor.com/2001/0921/p25s2-stin.html

This from the California Energy Commission:

http://www.energyquest.ca.gov/time_machine/centennial_lightbulb.html

There were also some short write ups from NPR and USAToday that provided links to the www.centennialbulb.org site. Unfortunately I am unable to pull up that site.

Who knows, but apparently it is only a 4 watt bulb so maybe it does not have the same thermal stresses that most light bulbs undergo, so perhaps this one is true. I have heard of this legend as well but never gave it any thought. It seems to be true but then again..... :uhh:

3. Jan 9, 2005

### Ivan Seeking

Staff Emeritus
I have a...clears throat...1976 Guinness book that mentions this light bulb.

Last edited: Jan 9, 2005
4. Jan 10, 2005

### SGT

Most light bulbs burn when turned on or off, due to transients (electric and thermal). A bulb that is continuously on is more likely to last longer, especially if it is a low power one.

5. Jan 10, 2005

### DaveC426913

Yeah, right. So why do I replace the bulbs in my workroom every couple of weeks even though I leave them on all the time?

6. Jan 10, 2005

### Ivan Seeking

Staff Emeritus
I know!!! :grumpy: :grumpy: :grumpy: The quality of incandescent bulbs is in the pooper. I've also had bulbs and sockets that won't work together. I can't screw in the ****** lightbulbs!

7. Jan 10, 2005

### Staff: Mentor

If you want a light bulb that costs a buck, buy an incandescent - if you want one that lasts 20 years (and burns a quarter of the energy), buy a fluroescent.

8. Jan 10, 2005

### Gokul43201

Staff Emeritus
A few years ago (5-ish ?), people were doing backflips when Gallium Nitride based blue LEDs were developed. One of the suggested applications was in lightbulbs that would have lives of tens of years. I ever remember this being employed in traffic lights, somewhere in the UK. Anything come of this ?

9. Jan 10, 2005

### Staff: Mentor

The light bulbs in the chandelier in my foyer have been working for 13 years. These are some of the most used lights in the house being turned on and off every time someone leaves or enters the house or goes up and down the stairs.

Thank goodness because I will need a very high ladder to reach them if they need to be changed.

10. Jan 11, 2005

### hypnagogue

Staff Emeritus
I wouldn't be surprised if this was intentional on the part of the manufacturers, in order to get customers to buy the product more frequently.

11. Jan 11, 2005

### Ivan Seeking

Staff Emeritus
We have high efficiency lighting almost everywhere, but we use regular bulbs as heaters in outbuildings like the pump house. When we first bought this place, one bulb lasted all winter or even several winters. Now I'm lucky if they last a month. I don't know hynagogue; planned obsolescence, or maybe just increasing cheap manufacturing, or both.

12. Jan 11, 2005

### brewnog

As far as I know, we've had shedloads of LEDs in our red lights for years, just starting to see some green ones too (not sure about amber!).

13. Jan 11, 2005

### motai

My friends and I have long speculated such a notion. It makes business sense, but this may also be due to the trend in the manufacturing industry as everything becomes more disposable. Or both. Another conspiracy theory to think about .

I wouldn't mind not having to change light bulbs ever again. All of the highly used lights in my home are fluorescent, the less-trafficked ones still are incandescent.

14. Jan 11, 2005

### Staff: Mentor

I have a blue LED flashlight - the batteries last forever.

15. Jan 12, 2005

### DaveC426913

Sure, but I'd think all that would do is create a quality vacuum, providing an edge for competing products.

See, that kind of planned obsolescence is used in the automobile industry, but there are so few competitors (in the domestic market) that they can cooperate.

But nothing's stopping Joe-nobody from creating a long-lasting light bulb.

16. Jan 12, 2005

### Staff: Mentor

The thing people aren't getting here is that replacement cost of a lightbulb is absolutely trivial compared to the energy it uses. Its not even worth thinking about, much less complaining about. Really, you're complaining about convenience - that's not anywhere near the biggest concern when picking a light-bulb. But since we are....

Bulbs.com sells Phillips 100w incandescents (for about $0.50 apiece (1,620 lumens, 750 hours). That's almost exactly one month of continuous usage at 50 cents a month to replace. Absolutely trivial. The energy it uses in that month, however (at 12.5 cents per kWh) costs you$935!!

The Phillips Marathon (a relatively expensive CF) goes for $12 (1,750 lumens, 25w, 10,000hr). That's about 13.5 months of usage, or about 89 cents a month if used continuously. Energy used per month of operation:$233.

Now even in a business employing a couple of hundred people, where a 750 hour life could mean changing 1 or 2 lamps a day, clearly, lamp life (cost of the lamp+cost of 10 minutes for the janitor to replace the lamp) is trivial compared to the cost of the energy it uses: even if you reverse the lifespans of fluorescents and incandescents, businesses would still use the one that used less energy! And for a home, where the reality is changing 1 lamp every month or so, its also a trivial consideration (Evo's chandelier notwithstanding).

Keep your eye on the ball, people!!

17. Jan 12, 2005

### Ivan Seeking

Staff Emeritus

$9.35$2.34

18. Jan 12, 2005

### Ivan Seeking

Staff Emeritus
Who wasn't getting it? I'm confused.