100 Year Light Bulbs ??????????????
Huh ?
Not one of them has failed.
I'd like to buy some more but alas, Sam's has never had them again and I
haven't found them anywhere. Has anyone seen them ?
Thanks
Andre de Guerin
Yep, these turn up in various catalogues every now and then .
IIRC they use a specially designed low strain filament that is set up
so that it does not flex in normal use .They also use a filament rated
for about 2 times the mains voltage, so it never gets hot enough to
fail .
Of course this makes them more expensive . :)
BTW LEDs still last longer then these bulbs .. !
>
>Thanks
>
>
Sam Goldwasser
The most serious failing of these claims is that while the life is long,
the efficiency is much poorer than normal bulbs - you get a lot less light
for the same watts. There is no magic way of increasing the life of an
incandescent lamos.
And, the major cost of running incandescent lamps is the electricity, not the
bulb replacement:
1000 hour bulb: 50 cents.
eletricity to run it for 1000 hours at 10 cents/kWh: $10.
So, if you don't care that they aren't as bright but are in inaccessible
locations so convenience of not changing bulbs as often outweighs all other
factors, sure buy expensive inefficient light bulbs. :)
But, you're losing money in the end using these.
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Peter Duck
s...@saul.cis.upenn.edu (Sam Goldwasser) wrote:
> ... the major cost of running incandescent lamps is the electricity,
> not the bulb replacement:
> 1000 hour bulb: 50 cents.
> eletricity to run it for 1000 hours at 10 cents/kWh: $10.
> So, if you don't care that they aren't as bright but are in inaccessible
> locations so convenience of not changing bulbs as often outweighs all
> other factors, sure buy expensive inefficient light bulbs. :)
> But, you're losing money in the end using these.
Though they don't last for ever, 'compact fluorescents' are IMO the
optimum solution in most situations, with the bonus of feeling that one
is 'doing the best for the planet'.
--
Peter Duck <pd...@zetnet.co.uk>
Sam Goldwasser
Unfortunately, there is a lot of variability in both light output, color
temperature, and actual lifetime. And, not all CFs can be popped into
an existing fixture either because they won't fit physically or because
some won't operate properly on a dimmer or a timed switch.
Here is a bit more info: http://www.misty.com/people/don/cf.html
and some recommendations:
http://www.misty.com/people/don/cfbest.html
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Kahlua53
The company sold a lot of these and now they went out of business becuase they
last so long...
Just a thought.
Remove NoSpam to reply, Thanks
JL Webb
in Edison's time! My friend has lights in his home that have original Edison
bulbs in them and they still work. Obviously if they made bulbs like this
today, the bulb companies would go out of business. They depend on people
needing to buy bulbs every few months and make the bulbs with filaments that
run too bright and thus have a very short life. One solution is to use light
dimmers and run today's bulbs at a lower voltage. I have bulbs for over 15
years that are still working because I run them at a lower voltage with the
dimmers. And I am one of those people that do NOT turn the lights off
everytime I leave a room.
gudule
the bulb socket , increasing its life . Anyone know if they are still
available???? How were they called ??? Thanks.
======================================
"JL Webb" <jlw...@iname.com> wrote in message
news:3B119DB5...@iname.com...
Gary Avrett
that was before they started hiring engineers to design in a particular
failure rate.
Gary
"Kahlua53" <kahl...@aol.comNoSpam> wrote in message
news:20010527200909...@ng-ce1.aol.com...
Sam Goldwasser
And he hasn't sold them on eBay yet? Sure. :) And, BTW, you can buy
authentic looking copies of Edison bulbs.
I think you kind of answered your own question. Except that did you figure
the amount and cost of additional power you've used being penny-wise but
pound foolish?
Cost of 1,000 hour light bulb: $0.50.
Cost of power at $0.10/kWh to run light bulb over its life: $10.00.
OK, you want a 100 year light bulb? Take two ordinary light bulbs and
wire them in series. Each will now dissipate perhaps 1/3 of their rated
wattage (filament resistance is non-linear) and will probably last well
over 100 years (you do the experiment!). The total light output will
probably be less than 1/2 that of a single bulb.
The voltage on each will be half line voltage, life is something like the
12th or 13th or 14th power of the rated voltage/actual voltage. Do the
math. Any light bulb can be made to last 100 years. Go to www.misty.com/~don
for light bulb info.
Did anyone ever ask how efficient Edison's bulbs were? A lot less than
a modern bulb. You can trade off efficiency against life but you can't
have both. And Edison's carbon filaments could not run anywhere near the
temperature as tungsten. Cooler->less efficient. (more orange, less white).
Cost of power to run a pair of somewhat higher wattage 1,000 year light bulbs
to obtain the same light as a single normal light bulb for 1,000 hours: $15-20.
This isn's some grand conspiracy! :)
James Sweet
are available that put out light nearly on par with incandescent,
they're about $9, and they last ages while using very low power. I also
found some teeny little ones that while the light isn't quite as nice,
they fit in just about anything.
Al Savage
wrote:
> I've noticed lately that compact fluorescents have really matured, some
> are available that put out light nearly on par with incandescent,
> they're about $9, and they last ages while using very low power. I also
> found some teeny little ones that while the light isn't quite as nice,
> they fit in just about anything.
I was an early adopter of some of GE's CF units. I bought around eight
of them, about seven years ago or so, for about $18/ea. Of that batch,
two have failed in use, and I received replacements of both from GE
without having to provide POP. Decent customer service. Each time I
pointed out that the warranty for them was (something like 10k hours).
The first one they wanted shipped back; the second they didn't. I
rather like them.
In multiple fixture situations, I generally leave ONE incandescent in
place, so I have some light immediately, because the CFs do tend to have
a warmup period, starting out fairly dim.
Samples I've bought and tried form The "Lights of America" and
"Sylvania" brands have been poorer quality, and I've had several of the
former fail within two years. You get what you pay for.
--
Regards,
Al S.
* Hillman & Rootes Group manuals online: http://asavage.fdns.net/Hillman
* Ford Falcon manuals online: http://FalconFAQ.fdns.net
This OS/2 system ("Tori", W4 FP15) uptime is 0 days 14:25 hours
Andy Cuffe
> of them, about seven years ago or so, for about $18/ea. Of that batch,
> two have failed in use, and I received replacements of both from GE
> without having to provide POP. Decent customer service. Each time I
> pointed out that the warranty for them was (something like 10k hours).
> The first one they wanted shipped back; the second they didn't. I
> rather like them.
>
I also like those Ge 60W equivalent with the spiral tube. They fit in
most places and so far the only one that failes was because it rolled
off the table when I installing it. For dimmers, Philips has a dimmable
one that seems pretty good. It flickers at really low brightness, but
otherwise it's fine. They cost about the same as the non-dimmable
equivalent (I paid $14). The first one I bought failed within a week,
but I took it back to the store and the new one has been fine for almost
a year. I agree that lights of america are junk. Of 3 of their
'Twister' models, one failed in less than a month and the other's put
out MUCH less light than they claim. They should be taken off the
market because anyone who buys one might think all CFs are like that.
--
Andy Cuffe
balt...@psu.edu
Stein-Olav Lund
Sam Goldwasser wrote:
> This discussion comes up from time to time on the sci.electronics groups.
>
> The most serious failing of these claims is that while the life is long,
> the efficiency is much poorer than normal bulbs - you get a lot less light
> for the same watts. There is no magic way of increasing the life of an
> incandescent lamos.
>
> And, the major cost of running incandescent lamps is the electricity, not the
> bulb replacement:
>
> 1000 hour bulb: 50 cents.
> eletricity to run it for 1000 hours at 10 cents/kWh: $10.
Here in Norway the 'standard' lightbulbs with E27 screw and normal
glass bulb, 25-100W, are made to last 2500 hours.
(This only applied to these bulbs, others are 1000hr bulbs)
The reason is (was) our cheap hydroelectric power.
Now it isn't as cheap and plentiful as it used to be, and bulbs
from EU countries (with 1000 hr life) are made in bigger numbers and
to lower prices, so I expext we will see less and less of our 2500hr bulbs
in the future.
Stein
JL Webb
> > the efficiency is much poorer than normal bulbs - you get a lot less light
> > for the same watts.
It is NOT the same watts if you have a dimmer and run the filament lower. And you
are looking at this thing backwards. The filament should never be running as
bright as they do. (this is so they will burn out quicker and the company sells
more bulbs) By running the filament this hot you are getting MORE light than
normal, but also have to replace the bulb every so often.
> There is no magic way of increasing the life of an
> > incandescent lamos.
Don't know about "lamos" but a light bulb you can increase the life, or again, you
can DECREASE the life by running the filament too bright.
> > And, the major cost of running incandescent lamps is the electricity, not the
> > bulb replacement:
You are using BOTH more electricity AND buying too many bulbs if you don't use a
dimmer on today's bulbs. Using a dimmer uses LESS electricity (and cost) and you
never have to buy replacement bulbs unless you hit one with something by accident.
Sam Goldwasser
both a lot dimmer and a lot less efficient. So, if you're happy with less
light, by all means use the long life bulbs. Even figuring in the cost
of replacement bulbs, using a lower wattage normal bulb is probably a
better deal if you're happy with the lower light output. Electricity usage
is so much more significant than bulb costs that there isn't even a meaningful
contest!
A dimmer is less efficient at reducing energy costs than simply using a
lower wattage bulb. While the dimmer is nearly 100 percent efficient,
running the bulb at lower power reduces its efficiency significantly.
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JL Webb
> You're missing the point. I can make a bulb last 1000 years but it will be
> both a lot dimmer and a lot less efficient.
No you are missing the point. You are running the bulb too bright, and that is why they
blow out so quickly. It is not efficient at all to keep blowing out bulbs and buying new
ones.
I can also drive my car in lower gears and get more power while having to get the
transmission replaced several times.
> So, if you're happy with less
> light, by all means use the long life bulbs.
I don't use "long life" bulbs, I use regular bulbs at the PROPER voltage for the
filaments used in them.
I don't have "less light" because I use more bulbs, thus more light. I can use the same
amount of light, and with more bulbs, the same amount of electricity, but never buy any
more bulbs. The difference is that by running the filaments too bright, you have to keep
buying bulbs. I am still using the very same bulbs for over 10 years since I learned
this and got tired of replacing bulbs every month and figured out why my friend's
original edison bulbs still work today, while modern bulbs only last a few months. The
new bulbs are designed to run at a lower voltage. This is done on purpose so that normal
house voltage shortens the life of the bulb and the company sells more bulbs.
> A dimmer is less efficient at reducing energy costs than simply using a
> lower wattage bulb.
There is absolutely no difference at all. I could run a 100 watt bulb through a dimmer
so that only 60 watts of electricity is used, and you could run a 60 watt bulb without a
dimmer and there would be no difference at all in energy costs, other than the fact that
you would have to waste money buying new 60 watt bulbs every few months, while I could go
decades without having to do so.
Peter Duck
JL Webb <jlw...@iname.com> wrote:
> > > And, the major cost of running incandescent lamps is the
> > > electricity, not the bulb replacement:
> You are using BOTH more electricity AND buying too many bulbs if you
> don't use a dimmer on today's bulbs. Using a dimmer uses LESS
> electricity (and cost) and you never have to buy replacement bulbs
> unless you hit one with something by accident.
What you say is true, but only by omitting any mention of the light
that's the whole purpose.
Sam is quite correct: the cheapest way of providing any required
quantity of light (number of lumen-hours, candlepower-hours, or
whatever) from an incandescent lamp is to run it hot enough that it does
have a rather limited life.
Despite the cynical views expressed in this thread, major
lamp-manufactures do optimise the trade-off between energy-cost and
lamp-cost for minimum total cost to the user.
Not sheer altruism: it's a fiercely competitive business, and though
most individual domestic users would be exploitable the large-scale
business/commercial ones aren't (and in many countries there are vocal
'consumer watchdogs' of one sort or another).
As energy-costs rise and the lamps become cheaper, it's right that
lamp-life should decrease, but you won't find any strikingly profitable
lamp-makers in this global and now rather lo-tech industry with low
'entry costs'.
The producers of the electricity are in a happier position, not just in
California ...
--
Peter Duck <pd...@zetnet.co.uk>
Sam Goldwasser
Cost of running a 100 W 1,000 hour bulb: $10 (assuming 10 cents/kWh).
To get the same light with a 2,000 hour bulb may require 110 W (I don't have
the exact number but someone can check).
Making this assumption, cost of electricity to run a 2,000 hour bulb for 1,000
hours: $11.
Total cost over 2,000 hours using long life bulb: $22.00 + cost of 2,000
hour bulb.
Total cost over 2,000 hours using normal bulb: $21.00 including bulbs.
The cost of power so dominates the equation that unless bulbs are in
hard to reach places or you simply can't be bothered, the shorter lived
bulbs are cheaper in the long run.
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JL Webb
> Cost of 100 W 1,000 hour bulb: $0.50.
> To get the same light with a 2,000 hour bulb may require
Why are you comparing two different type bulbs? (apples and oranges)
I am talking about the SAME type bulb, just not abusing the filament in it, thus making it last
almost forever.
Joe
get from your 100w bulb dimmed down to consume 60w.
JL Webb wrote in message <3B17027A...@iname.com>...
JL Webb
> get from your 100w bulb dimmed down to consume 60w.
No he's not, read again....
> >Sam Goldwasser wrote:
> >
> >> Cost of 100 W 1,000 hour bulb: $0.50.
> >> To get the same light with a 2,000 hour bulb may require
He is comparing a 1,000 hour bulb with a 2,000 hour bulb.
This is OBVIOUSLY a game of trolling, and I will not dance for your amusement
any longer.
Andy Cuffe
>
>
> What you say is true, but only by omitting any mention of the light
> that's the whole purpose.
>
> Sam is quite correct: the cheapest way of providing any required
> quantity of light (number of lumen-hours, candlepower-hours, or
> whatever) from an incandescent lamp is to run it hot enough that it
does
> have a rather limited life.
>
> Despite the cynical views expressed in this thread, major
> lamp-manufactures do optimise the trade-off between energy-cost and
> lamp-cost for minimum total cost to the user.
>
> Not sheer altruism: it's a fiercely competitive business, and though
> most individual domestic users would be exploitable the large-scale
> business/commercial ones aren't (and in many countries there are vocal
> 'consumer watchdogs' of one sort or another).
>
> As energy-costs rise and the lamps become cheaper, it's right that
> lamp-life should decrease, but you won't find any strikingly profitable
> lamp-makers in this global and now rather lo-tech industry with low
> 'entry costs'.
>
> The producers of the electricity are in a happier position, not just in
> California ...
>
> --
> Peter Duck <pd...@zetnet.co.uk>
Exactly, if you need 5 60 W 100 year bulbs to equal the light output of
4 60W 1000 hour bulbs, then obviously, the cost of running the 100 year
bulbs will be much higher. If you don't mind lower light output, then
you could use 4 100 year bulbs, but you're getting less light for the
same money. They only make sense in locations where changing them is
difficult, or light output is unimportant. Of course, if light output
is unimportant, you'll save even more by just using a regluar bulb of a
lower wattage.
--
Andy Cuffe
balt...@psu.edu
Andy Cuffe
> I don't use "long life" bulbs, I use regular bulbs at the PROPER voltage for the
> filaments used in them.
> I don't have "less light" because I use more bulbs, thus more light. I can use the same
> amount of light, and with more bulbs, the same amount of electricity, but never buy any
> more bulbs.
By using more bulbs, you use more electricity. It's a simple fact that
when a bulb is run cooler it produces less visible light per watt of
power. If you run a 60W bulb at a lower voltage to make it consume only
40W, it will produce much less light than a 1000 hour 40W bulb running
at full voltage. To get the same light as the 40W bulb, you might have
to run a 75W bulb at 60W, for example. Now you're using 20W more power
which will cost way more than the extra 40W bulbs.
--
Andy Cuffe
balt...@psu.edu
Sam Goldwasser
You can't get long life AND high efficiency AND the same light output
in the same incandescent lamp at the same time.
If you run the lamp at lower voltage you get less light AND less efficiency
but longer life.
I have no problem with you running lamps at some reduced stress level. E.g.,
buying 130 V bulbs and running them a 115 V. Just understand that if you
ultimately need the same amount of light and thus have to run more lamps to
get it, you lose in the long run with respect to overall costs.
Those Edison bulbs are almost certainly pitifully inefficient.
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Sam Goldwasser
Probably, but it's not me doing the trolling. However, I do admit this is
amusing but doesn't hold a light bulb to the "Fooling the Power Meter" thread
awhile back. :)
The primary difference between a 1,000 hour bulb and 2,000 hour bulb is that
the latter has a slightly thicker longer filament so it runs cooler,
puts out less light, but lasts longer. Thus the comparison. Go look at
the packages, lumens/watt.
Jim Adney
>You are using BOTH more electricity AND buying too many bulbs if you don't use a
>dimmer on today's bulbs. Using a dimmer uses LESS electricity (and cost) and you
>never have to buy replacement bulbs unless you hit one with something by accident.
What you say is true, but what you don't mention is that by running
them cooler you get less visible light and more heat PER WATT than you
did before. So while the power has gone down, the conversion
efficiency to visible light has gone down faster.
In the end you may be better off just using a lower wattage bulb, or
do the RIGHT thing and invest in a good compact fluorescent
replacement.
-
-----------------------------------------------
Jim Adney jad...@vwtype3.org
Madison,Wisconsin USA
-----------------------------------------------
Peter Duck
s...@saul.cis.upenn.edu (Sam Goldwasser) wrote:
> ... I do admit this is
> amusing but doesn't hold a light bulb to the "Fooling the Power Meter"
> thread awhile back. :)
I (also?) have been trying to remember that poster's name, for obvious
reasons ...
--
Peter Duck <pd...@zetnet.co.uk>
James Sweet
significantly less light than a 60W bulb running at full voltage
produces.
James Sweet
this group, and has been around on here much longer than I am. I'd say
it's safe to assume he knows exactly what he's talking about.
Tom MacIntyre
Sam Goldwasser
> You're one to talk, Sam is quite possibly the most respected member of
> this group, and has been around on here much longer than I am. I'd say
> it's safe to assume he knows exactly what he's talking about.
Wow, I wish that were true. (The part about knowing exactly what I'm
talking about all the time.) :)
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JL Webb wrote:
James Sweet
mike.holliday1
(Sam Goldwasser) wrote:
> In article <3B170C13...@iname.com> JL Webb <jlw...@iname.com> writes:
>
>> > Sam is saying he gets more light output from his normal 60w bulb than you
>> > get from your 100w bulb dimmed down to consume 60w.
>
>> No he's not, read again....
>
>> > >Sam Goldwasser wrote:
>> > >
>> > >> Cost of 100 W 1,000 hour bulb: $0.50.
>> > >> To get the same light with a 2,000 hour bulb may require
>
>> He is comparing a 1,000 hour bulb with a 2,000 hour bulb.
>> This is OBVIOUSLY a game of trolling, and I will not dance for your amusement
>> any longer.
>
> Probably, but it's not me doing the trolling. However, I do admit this is
> amusing but doesn't hold a light bulb to the "Fooling the Power Meter" thread
> awhile back. :)
>
> The primary difference between a 1,000 hour bulb and 2,000 hour bulb is that
> the latter has a slightly thicker longer filament so it runs cooler,
> puts out less light, but lasts longer. Thus the comparison. Go look at
> the packages, lumens/watt.
>
There's one thing I haven't seen mentioned in this thread which I think is
also significant; when you run the filament cool, not only does it put out
less visible light per watt of total power; the spectrum of the light in the
visible region changes, with much less light in the blue/green region and
more at the red end. This may be fine for people who'd really rather be
using candlelight, but it's no good for many applications where colour
rendering is important. The 1000 hour bulb has a colour balance which is
still much redder than sunlight; I guess that this was considered acceptable
when deciding on the compromise to go for since getting something similar to
sunlight might reduce the life to under 100 hours.
My understanding of the position here in the UK is that long-life (around
2000 hour) lamps have been available for many years, but they're mainly
usied in locations that are difficult to get to to change bulbs, and
non-domestic locations, where in general there's an additional cost, that of
the wages for the person changing the bulbs. (In fact the cost of changing
bulbs can be so important that many establishments will change all the bulbs
in an area as soon as enough of them have failed to make replacement
necessary)
Mike Holliday
Peter Duck
tmac...@ns.sympatico.ca (Tom MacIntyre) wrote:
> >> ... doesn't hold a light bulb to the "Fooling the Power Meter"
> >> thread awhile back. :)
> >I (also?) have been trying to remember that poster's name, for obvious
> >reasons ...
> RalphWM...
Thanks, Tom: I can stop trying to dredge it from my failing memory.
Presumably someone different (as, anyway, was the writing-style, for
lack of a worse term)
I can quite believe that the Flat Earth Society has no difficulty in
finding members ...
--
Peter Duck <pd...@zetnet.co.uk>
Asimov
--- on the topic of "Re: 100 Year Light Bulbs ??????????????"
SG> OK, I admit it. I haven't a clue of what your trying to prove. :)
SG> You can't get long life AND high efficiency AND the same light output
SG> in the same incandescent lamp at the same time.
SG> If you run the lamp at lower voltage you get less light AND less
SG> efficiency but longer life.
SG> I have no problem with you running lamps at some reduced stress level.
SG> E.g., buying 130 V bulbs and running them a 115 V. Just understand
SG> that if you ultimately need the same amount of light and thus have to
SG> run more lamps to get it, you lose in the long run with respect to
SG> overall costs.
SG> Those Edison bulbs are almost certainly pitifully inefficient.
I captured a relevant post from a previous debate on this matter:
You're right! There's nothing more to discuss after a little study.
> Within the (1977, 5th edition) General Electric SCR Manual can be found
> interesting data on tungsten filament lamps.
>
> Figure 14 graphs, among other things, candlepower and life expectancy
> as functions of "percent of design volts".
>
> At V = 70%, the life expectancy is increased to ~60x - 70x. However
> candlepower falls to ~25% of the originally designed target.
>
> The following table shows life expectancy, candlepower, and current
> for various supply voltages. I have computed input power and
> efficiency for each of the data sets. In doing so I have assumed that
> Efficiency = Candlepower / Power Input.
>
> % rated V Life %Candlepower %Current % Power I/P % Efficiency
> --------------------------------------------------------------------
> 60 500x 10 75 45 22
> 70 65x 25 81 57 44
> 80 15x 40 88 70 57
> 90 3x 60 94 85 71
> 100 1x 100 100 100 100
> 110 0.3x 140 106 117 120
> 120 0.1x 190 113 136 140
> 130 0.03x 250 119 155 161
>
... Thomas Edison invented the "Light Emitting Resistor"
Lionel Wagner
"Asimov" (warpcastgate@-removethis-bbs.juxtaposition.dynip.com) writes:
>
> I captured a relevant post from a previous debate on this matter:
> You're right! There's nothing more to discuss after a little study.
>
>> Within the (1977, 5th edition) General Electric SCR Manual can be found
>> interesting data on tungsten filament lamps.
>>
>> Figure 14 graphs, among other things, candlepower and life expectancy
>> as functions of "percent of design volts".
>>
>> candlepower falls to ~25% of the originally designed target.
>>
>> The following table shows life expectancy, candlepower, and current
>> for various supply voltages. I have computed input power and
>> efficiency for each of the data sets. In doing so I have assumed that
>>
>> % rated V Life %Candlepower %Current % Power I/P % Efficiency
>> --------------------------------------------------------------------
>> 60 500x 10 75 45 22
>> 70 65x 25 81 57 44
>> 80 15x 40 88 70 57
>> 90 3x 60 94 85 71
>> 100 1x 100 100 100 100
>> 110 0.3x 140 106 117 120
>> 120 0.1x 190 113 136 140
>> 130 0.03x 250 119 155 161
>>
>
Halogen bulbs can give a decent amount of light at half voltage.
--
,_,
Lionel * Retired Audio/Visual Electronic Technician (O,O)
Wagner * Patron member, National Capital Freenet ( )
------------<best viewed with Fixed(width)Sys font>--------"-"-
Sam Goldwasser
much different except that what is considered 100 percent of nominal voltage
will change because the halogen cycle extends life while running at a higher
filament temperature.
So (these numbers are a guess), you'll be running at the 120 or 130 percent
point on that chart but still get rated life.
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David Harmon
JL Webb <jlw...@iname.com> wrote:
>Sam Goldwasser wrote:
>
>> Cost of 100 W 1,000 hour bulb: $0.50.
>> To get the same light with a 2,000 hour bulb may require
>
>Why are you comparing two different type bulbs? (apples and oranges)
>I am talking about the SAME type bulb, just not abusing the filament in it, thus making it last
>almost forever.
No, you are the one comparing apples and oranges. Sam is comparing two
different ways of getting the same light. The whole point of using a
light bulb is to get the light you need.
You are saying that if you use less light it can be cheaper. Duh.
Don Klipstein
>
>It is NOT the same watts if you have a dimmer and run the filament lower.
>You are using BOTH more electricity AND buying too many bulbs if you
>don't use a dimmer on today's bulbs. Using a dimmer uses LESS
>electricity (and cost) and you never have to buy replacement bulbs
>unless you hit one with something by accident.
Dim a standard 750 100 watt bulb until it uses 75 watts of electricity
and it puts out about as much light as a standard 60 watt 1000 hour
bulb. (I mean usual USA "standard" A19's.) Believe me, the electric bill
from those extra 15 watts will cost (on USA nationwide average) $1.40,
maybe $1.50 in 1,000 hours. Even Ivy League college bookstores and those
chain drug stores that have a store in every neighborhood and charge
convenience store prices for light bulbs don't charge $1.40 per bulb.
- Don Klipstein (d...@misty.com)
Don Klipstein
>
>There is absolutely no difference at all. I could run a 100 watt bulb
>through a dimmer so that only 60 watts of electricity is used, and you
>could run a 60 watt bulb without a dimmer and there would be no
>difference at all in energy costs, other than the fact that you would
>have to waste money buying new 60 watt bulbs every few months, while I
>could go decades without having to do so.
Like h*** there is no difference. Dim a 100 watt bulb so that you use
60 watts of electricity and it has brightness more like a 40 watt bulb
than a 60 watt one - save 20 watts and you save about a dollar per 500
operating hours at the USA national average cost of electricity!
- Don Klipstein (d...@misty.com)
http://www.misty.com/~don/index.html
http://www.misty.com/~don/bulb1.html
Don Klipstein
>Sam Goldwasser wrote:
>
>> Cost of 100 W 1,000 hour bulb: $0.50.
True.
>Why are you comparing two different type bulbs? (apples and oranges)
>I am talking about the SAME type bulb, just not abusing the filament in
>it, thus making it last almost forever.
Actually, different degrees of the same situation. 2000 hour vs. 1000
hour is a mild case, dimming 100 watt bulb to consume 60 watts is a more
severe case. In both cases cost of achieving a given amount of light is
increased because electricity cost of achieving that much light increases
more than your savings on bulbs.
- Don Klipstein (d...@misty.com)
Don Klipstein
>"Asimov" (warpcastgate@-removethis-bbs.juxtaposition.dynip.com) writes:
>> I captured a relevant post from a previous debate on this matter:
>>
>Halogen bulbs can give a decent amount of light at half voltage.
Light output as a function of voltage is a little less extreme in
variation but still economically disfavors dimming them.
Also dimming a halogen (or at least ones of longer life than the usual
non-halogen it would replace) does not increase the life as much as it
increases life of non-halogen! Halogen has an additional wear mode that
usually does not benefit from dimming - the halogen erodes cooler ends of
the filament and that process is not slowed much by operating dimmed.
However, dimmed halogens may benefit from soft-starting to the extent
usually claimed for regular bulbs (possibly optimistically double the
life?). Regular bulbs hardly gain life from soft-starting means except
from most soft-starters also dimming them a little. Most regular bulbs do
not suffer damage from a hard cold start; but merely become unable to
survive one just a little before becoming unable to survive steady
operation.
More details in http://www.misty.com/~don/bulb1.html
- Don Klipstein (d...@misty.com)
Bruce Torelli
I'm an avionics engineer for a commercial airline. I used to be responsible
for lighting systems on a fleet of DC-9s. I found you web page to be a
great help a number of times. I appreciate you sharing all that good info.
Bruce Torelli
Atlanta GA
"Don Klipstein" <d...@manx.misty.com> wrote in message
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