Lifecycle Energy Costs of LED, CFL Bulbs Calculated
necro81 writes "The NY Times is reporting on a new study from Osram, a German lighting manufacturer, which has calculated the total lifecycle energy costs of three lightbulb technologies and found that both LEDs and CFLs use approximately 20% of the energy of incandescents over their lifetimes. While it is well known that the newer lighting technologies use a fraction of the energy of incandescents to produce the same amount of light, it has not been proven whether higher manufacturing energy costs kept the new lighting from offering a net gain. The study found that the manufacturing and distribution energy costs of all lightbulb technologies are only about 2% of their total lifetime energy cost — a tiny fraction of the energy used to produce light." The study uses the assumption that LEDs last 2.5 times longer than CFLs, and 25 times longer than incandescents.
Assuming LEDs last 2.5 times as long as LEDs, we conclude that LEDs last infinitely long and there is nothing superior except for LEDs.
God spoke to me.
Does anyone know if LED lighting can save on power over CFL with the same output (lumens)?
I purchased some LED bulbs and they tend to be much more expensive and the savings (watt rating) is very negligible. What makes LED more attractive? Is it just the longer life time?
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Anonymous Coward Sig 2.0:
MADONNA IS THE BEST!!
Impeach Obama; install Madonna; end the war!
Currently listening to: Madonna - Like a Virgin; Justify My Sex remix.flac
Surely they meant that LEDs last 2.5 times as long as traditional incandescents. Which is absurd actually... LEDs last a lot longer.
How come no mention of Halogens, I wonder?
Or x is undefined (as in infinity) is also a solution.
How can these "editors" screw up a single sentence? They're not even janitors.
Only the State obtains its revenue by coercion. - Murray Rothbard
"LEDs last 2.5 times as long as LEDs"
yeah...
http://www.zombieapocalypse.tv/
No one cares about the trivial solution.
I know, I know, buzzword alert.
Whats the TCO?
$X for bulb
$Y per kwh (cite sources, current prices in what locale, projected prices)
Z lifetime
Q consumption rate
Google shows a few results from manufacturers press releases.
Is heat output. More or less, any energy that isn't becoming light is becoming heat. Now in some areas of the world, that matters little to none. However in hot climates, it does. An incandescent produces more heat which gets dumped in to the air in your house. You then have to run your AC more often. So you end up paying double for the power, in terms of using it and then eliminating the excess. That's one reason I rather like CFLs is that they heat up my place less. I live in the desert so that is a non-trivial thing.
Also, they can have a much more natural white point. I like the fact that you can get CFLs with a white around 6000, which is closer to what you get from the sun on a bright day. Just a much nicer quality of light. You do generally need to pay more to get higher quality ones with a better spectrum, but I'd say it is worth it.
This is also true for extremely small values of 2.5
In theory, they last a lot longer. Well-built ones could even last more than the life of the owner.
However, LEDs are really sensitive to heat (even more than CFLs), and fixtures designed for incandescent bulbs often trap heat. A lot of manufacturers also build them fast and cheap, so expected lifetime can sometimes be measured in hours.
Not a typewriter
While it is well known that the newer lighting technologies use a fraction of the energy of incandescents to produce the same amount of light, it has been unproven whether higher manufacturing energy costs kept the new lighting from offering a net gain. The study found that the manufacturing and distribution energy costs of all lightbulb technologies are only about 2% of their total lifetime energy cost — a tiny fraction of the energy used to produce light.
A CFL costs maybe $5 each (if you buy a pack with more than one), including the retail markup, and saves maybe $40/year in electricity for supposedly 7+ years. I know manufacturers probably get their energy a bit cheaper than home electric rates, but it can't possibly be the 56+ times cheaper that it would take for the $5 to cover more energy than the $40*7 saved does.
It seems a bit premature to go on about how great LED lighbulbs are when they don't seem to be purchasable. Sure you can buy crappy novelty bulbs -- 15W or 25W replacements. But your workhorse bulbs, your 100W equivalents --- I've never seen any for sale, and a brief web search didn't turn up anything useful. One day, yes, they will be a great leap forward. Until then, how about we maintain contact with reality?
The study uses the assumption that LEDs last 2.5 times as long as CFLs, and 25 times longer than incandescents.
The summary wording is incorrect on the frontpage of /., but correct on this page... scroll up and look.
Weird.
Do what thou wilt shall be the whole of the Law
Incandescent bulbs :
+ Cheap, we're used to the light
- terrible efficiency, short lifespan, fragile, sensitive to vibration, emit heat
CFLs :
+ much more efficient, very long lifespan
- not very dimmable, contain mercury, fragile, slow to start up in cold environs, reduced lifespan if toggled on and off
LEDs
+ extremely efficient, ridiculous lifespan (60,000 hours), almost bulletproof, can toggle on and off as much as you want, start up instantly in all environs, dimmable, no toxic materials. Basically almost perfect in every way.
- $$$$$$$$$$$$$$$$. Current generation light spectra is too high a color temperature to mimic incandescents. Current generation packaging creates a narrow, focused cone of light.
Summary : LED will pwn all once the problems are solved, and the problems appear solvable. Problems with other light technologies are inherent to the technology itself and not solvable. Once LED is perfected, the other two technologies will be useless.
Since this is an energy-saving technology, surely it has some fatal yet under-appreciated drawback that fully justifies my foregone decision never to change my habits or lifestyle for any reason and makes fools of the "greenies" in my own mind! You know, like how Hummers are actually more eco-friendly than the Prius, and how windmills screw with feng shui. I've always found an excuse to view all environmentalism as self-defeating before, don't let me down this time slashdot!
Doesn't anyone ever think of the children? What about Easy Bake Ovens? Have you ever tried to bake a tiny little cake from the heat emitted by LED bulb? No adult, let alone child, has that sort of patience.
Better known as 318230.
"The study uses the assumption that LEDs last 2.5 times longer than CFLs, and 25 times longer than incandescents."
So...
They made it all up.
They /guessed/.
They didn't do any research, and didn't actually study anything, they just invented some numbers, then played with them.
No wonder so many people think so poorly of the environmental movement, if garbage like this gets any sort of positive press at all.
At my old house they burned out a lot on me. Back then they were $5 a pop and it was rather irritating replacing the same bulb 3 times in a row during a several month period.
Camping on quad since 1996.
Now it's been fixed on the frontpage, too.
Good to see the editors actually do something... :)
Do what thou wilt shall be the whole of the Law
Well-built ones could even last more than the life of the owner.
And what if the owner is Schrodinger's Cat?
fixtures [...] often trap heat.
But LED's don't even make enough heat to melt the snow off the traffic lights without added heating elements. google
THL phish sticks
....the fact that you can't freaking READ by the damn lights. CFL == Crappy Fscking Light. I wish it weren't true, but I've tried dozens of brands, and even the ones that make me most happy are only good for general purpose hallway lights and such. I hate putting them in anywhere I have to read. For as bright as they seem to be, they are so narrow in spectrum as to be sort of lacking in their ability to illuminate.
So far, no experience with LED's on this subject.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
Currently, all the LEDs I've found are too pricey. I have found some cheap ones, but I wasn't satisfied with the light output, or the light quality. I've found ones I liked quite a lot (Color Kinetics makes some fantastic units) but they are too expensive and often not designed for socket replacement.
I think in a few more years it'll probalby be something for me to do, but not just yet. I have to be pleased with the light output and quality, and I'm really not going to pay more than $100 per bulb, and really probalby $50 or less.
Infinity isn't a number.
Even as x tends towards infinity, 2.5x=x is false for all values of x but zero.
I wonder if that's why my experience with LED bulbs is so varying. Three bulb-style LED lamps we've had to replace effectively every month (and in a 3-lamp fixture, means 3 a month!). They don't burn out, they just glow normally, then blink out suddenly. But some LED floodlights have lasted the whole duration (6+ months) with no issues at all. Strange.
Giving up on the LED bulbs and going to crack one open to see what actually failed. Going back to CFLs... even the quality ones are cheaper than the LED bulbs.
I am practically a professional light-bulb changer
So, how many of you does it take to... oh, never mind.
Space game using normal deck of cards: http://BattleCards.org
Incandescents are already 'banned' in many areas of the world (including where I live). That is to say, stores aren't allowed to sell new ones anymore (existing ones that are still going are OK obviously). The exception to this is weird form-factor lights that they don't mass-produce CFLs for (e.g. those little ones you put into bedside tables). But for standard overhead light fittings, incandescents have already gone the way of the dodo here.
Even factoring in the impact of recycling, their total lifecycle environmental impact is considerably less than incandescents. Many vendors that sell CFLs (e.g. hardware stores) also accept back dead ones. And if not, I just pop the dead ones in a box in the back of the car and take them to the dump next time I'm in that area anyway, so the 'extra' travel is minimal. For me at least, it's worth it. My electricity bills are at least $100/year less after moving to CFLs, and they produce less waste heat (which matters to me as I don't have AC!)
LEDs will be better though of course. They should be trashable just like incandescents were, while retaining the energy savings of CFLs.
I think it's gotta be a romulan plot, a ploy to start a war.. and takeover slashdot.. something to do with stealing the infinitely-long-lasting LED technology. The editors we all know and love don't make fixes like that [j/k]
the ballast used in the cfl's seem to have a limited on-off cycle life; or, the life expectancy is inversely proportional to the on time. If the typical on time is on the order of 5 minutes, you'll see less than 20% of the rated life expectancy. To achieve the full life expectancy the on time has to be greater than 2 hours. Don't use them in bathrooms and similar locations where they'll be switched on and off a lot -- use standard incandescent or better yet halogen bulbs in those applications.
Hope for http://www.vu1.com/technology/technology.htm
No mercury, highly energy efficient, light quality identical to incandescent, not to expensive.
Why suffer if you break a light for some eco cult?
Wait for better tech and stay away from the lights of brain death.
Domestic spying is now "Benign Information Gathering"
You're thinking of the low-power versions. If you look at something higher-powered, such as a Cree XR-E, then yes - you will need decent heatsinking to prevent the LED from frying itself.
Your assumption is like talking about a P4 CPU, and assuming it has the same thermal requirements as a low-end ARM CPU. Without heatsinking, the P4 will melt in short order - but the ARM will be just fine.
Forget world peace, bring on -1 pointless
That study as reported in the details didn't show significant difference between overall LED and CFL efficiencies. But the article consistently pushed LEDs. The headline mentioned only LEDs; LEDs were mentioned every time continuing advances were touted, the mercury in CFLs were pointed out (but not the toxic byproducts unique to LED production). The article's picture shows LEDs, not CFLs.
Yet LEDs don't really compete with CFLs yet. The article does mention that even a 60W incandescent equivalent is just experimental in LEDs, though CFLs have brightnesses at all levels even far past equivalence to 100W incandescents. Meanwhile, LEDs still generally aren't as efficient as their equivalent brightness CFLs. And LEDs' extra inefficiency puts heat into rooms that then require extra cooling, which consumes more energy.
LEDs are probably going to outperform CFLs. Their colors will be better than CFLs, their efficiencies probably better than double CFLs. They're smaller, probably able to be less toxic to produce and discard. Their DC power offers better efficiency direct from solar power (or its battery storage) than AC CFLs can get. But not yet. This article makes LEDs seem better than CFLs, but they're not now. It's marketing disguised as reporting. Probably the lack of numbers in an article about engineering performance should be the tipoff.
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make install -not war
According to a previous Slashdot article: http://hardware.slashdot.org/story/09/07/07/0716247/Incandescent-Bulbs-Return-To-the-Cutting-Edge , and the impending NYT link; new-incandescent tech is still 10% better than CFL/LCD. And the sad thing is this NEW article today; sighted a quote from Philips; and yet no mention of their own "new-incandescent tech". I wouldn't expect the NYT to remember it's own words; let alone Philips's.
Till this belly button lint examining festival is over; I've stocked up on a life-time's worth of good-ole indoor floods. My house is outfitted with only these fixtures. Indoor floods are very poorly represented by a CFL/LED counterpart which doesn't look like an alien autopsy examination room. For some of us, the 20% increase in lighting-only utility bills is insignificant & meaningless.
Granted I *love* LED tech, but, as-yet ALL the bulbs I've purchased and played with are AWFUL, and more like a dim spot-light; and still the same over-exposed glow. Even the incredibly-expensive LED floods aren't worth the expense (see: www.spectrumlighting.com.au)
Don't get me started on how disgusting our freedom & liberty "loving" Congress is for legislating the death of incandescents. A better AND more efficient technology will win on its OWN merrit, by the market and consumer choice. Look what a disaster the legislated adjustment of the Day-light-savings was, in the name of energy savings.
Can you do that again as a car analogy?
http://www.chaotickingdoms.com
I wonder if this analysis took into account CFL's poor power factor. Cheap CFLs usually have a power factor of around 0.5, which causes substantial electrical losses compared to Incandescent bulbs, which are purely resistive (and therefore have a power factor of 1.0). LEDs, on the other hand, have a pretty good power factor. http://www.theengineer.co.uk/opinion/led-is-the-answer/299821.article
inconveniently, they're actually more efficient
All truths are inconvenient. Oh wait:
My experience is that CFLs have a short life span, perhaps the same as a regular bulb. Certainly less than advertised. I'm tired of replacing the bastard things. I think CFLs have been a con on the public. We should have waited for LEDs. I feel like I bought Betamax tapes. Its just like the fuel-efficiency sticker on a car - an efficiency normal people cannot achieve. The public screwed - once again.
However, LEDs are really sensitive to heat (even more than CFLs), and fixtures designed for incandescent bulbs often trap heat.
I had a couple multi-bulb fixtures. I put 3 9W CFLs in them. 2 of 3 burn out within a week. Every time. If LEDs are worse, then they'll never take off. If recessed lighting and enclosed fixtures will never work, then they are out. People already hate them for that, and if LEDs can't work in the majority of fixtures out there, they are a non-starter. I'm not going to redesign the lighting in my house. Count in that cost in them if they can't work in enclosed lighting and recessed lighting like incandescents do without a problem.
Learn to love Alaska
I'm a green centric guy, not to the point of insanity, but like many Slashdotters I do my best. Sadly there is little I can do with advanced bulbs thanks to the terrible wiring my 200 year old home has. No matter the bulb it is likely to blow out early into its expected life. I've tried them all an they all burn out. Sadly this means I buy cheap. Yes I know I should upgrade the wiring, but that is very expensive. I can't wait to join the revolution, but I need to have some less finicky bulbs or a huge pay increase to do it. Until then I suppose I'm part of the problem and not the solution.
The only place I've ever seen LED light bulbs is at http://www.ccrane.com/lights/led-light-bulbs/. Not associated with this company at all, they just send me a catalog every now and then. I'd definitely be interested in these, but the cost is still to high.
Life was hell, then I discovered Linux...
Halogens are only slightly more efficient.
If a normal lightbulb is about 2 - 2.5% efficient, a halogen gets 3-3.5%.
Meanwhile, a CFL is in the 11% range.
I have a set of 4 spotlights in my kitchen which I have 1 "40 LED" spot, 1 "Halogen" spot and 2 "Energy saving" spots. The Halogens last 2 months, the LEDs last 4 months and the Energy savers haven't been replaced in over a year. Halogens are much cheaper and brighter than LED and Energy savers. LEDs are expensive and need additional lighting for colour balance. Energy savers take 5 minutes to achieve full brightness. For this reason, I have the mixture in my kitchen. Halogen £0.79 Energy Saver £1.99 LED £4.99 I wont buy any more LED until the price is under £1.50
2.5*1=2.5
2.5*1=1?????
2.5*0=0
I can do you one based on technobabble.
Your assumption is like talking about a Dalek phase inversion apparatus, and assuming it has the same polarity requirements as a Gallifreyan warp transvortex node from a type 40 Tardis. With a polarity reversal modification by a rogue Timelord using a sonic screwdriver, the Dalek phase inversion machine will explode five minutes before then end of the last episode - but
I'm sorry, this analogy seems to have failed. I can sell let you have at a discount rate if you want to break it down for spares.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Without heatsinking, the P4 will melt in short order
Wrong. :)
Sigh... it's a freaking analogy, OK? 'Melt' doesn't have to be pedantically correct.
For the guy who wanted a car analogy... it's like trying to run a formula 1 engine at full load with the cooling rig from a 1980s civic.
Forget world peace, bring on -1 pointless
Before I mention LED's, the 3 main problems I see with CFL's today are:
1. They last nowhere near as long as they are marketed. We moved into an old house about 1.5 years ago. We almost immediately started replacing all incandescents with CFL's and that was completed within a few months. Until today, we have had to replace about 10-20% of the CFL's. Which means multiple failures within 1.5 years. Most of the CFL's sold here are marketed with a 6-10 year lifetime, so how is it that many are failing after a year or so? I stay away from the generic brands and only buy the more expensive CFL's from the major manufacturers (including the one mentioned in TFA). I know that CFL's should not be switched on and off at short intervals and we avoid that as much as we can, but this can only be taken so far. CFL's don't come anywhere near their stated lifetimes today.
2. They have a long warm-up time after switching them on. Most CFL's take about 10-20 seconds before they reach about 90% of their peak light output. This is just not acceptable in many cases. Take a closet for example. You turn on the light to look for something. But with a CFL, you have to stand there and wait while the light warms up before you can see anything. So you are standing there, waiting for the bulb to reach an acceptable brightness. This is unacceptable. In this case, you need light NOW. Not 10-20 seconds from now, but NOW. Some of the smaller CFL's meant to replace halogen spots are even worse, I have 3 in a coatroom and they have to be on almost a full minute before they reach 90% output.
3. Performance in the cold is far worse. Warm-up times increase exponentially in the cold. I have many outdoor lamps around my house and yard. Over time, these have also been replaced with CFL's. Some are on a twilight timer and this eliminates the problem of slow warm up (for the most part), but if I need extra light outdoors I need to switch the lights on a couple of minutes before I actually NEED the light, to give the bulbs a chance to warm up and produce usable light.
As I'm pretty fed up with CFL's weaknesses, I'm all ready for LED's once they solve the current problems:
- Broad spectrum daylight output is needed (today's LED's emit a fairly narrow spectrum or output a too cold color temperature)
- Better light diffusion and dispersion is needed to mimic incandescents (many LED's are too "point-source")
- Cost, the current prices for LED's are ridiculous
Waiting...
PS: I don't mention mercury and recycling because I live in Finland which has a good recycling system. Here, it is not a problem (or inconvenience) to recycle and we don't just throw everything in a landfill.
They burn out every week? You might have some seriously dirty power where you live. We have a few ceiling mounted, closed, multi bulb fixtures, and the CFL's in them don't burn out nearly as quick as yours. Current set has been going for about 2 years now. And they're on for at least 3 hours straight.
I just got a killowatt sort of thing, and I tested it on a CFL and on a LED (3W Luxeon); CFL has close to .5 power factor vs 1.0 for the LED. I was astonished how bad it was on the CFL. Sure it does not use much power but it wastes shittons of power in the transmission line as a result -- I'm just not billed for it. Thing is, it shouldn't be too hard to improve the PFC, should it?
3W, and now 5W per LED. Low power LEDs suck for lighting, even when you have 100s of them, I've found.
Also the semiconductor in the LED is encased in plastic, which is in turn in a metal+plastic casing. You really have to work hard to expose it. Even in a landfill most will never leak. The mass of dangerous material is tiny, anyway.
OTOH it's easy to break a CFL. The amount of mercury is ridiculously small, though.
25 incandescents = 2.5 CFLs = 1 LEDs - why are people only talking about how great that is? Where the evaluation of the impact on cost-of-failure (25 times higher for LEDs). To make an informed decision, cost of failure needs to be part of the equation. What the probability blubs are dead-on-arrival? what's the probability they stop functioning optimally/at all after 500 hours? 1.000 hours? 5.000? 10.000? Without knowing the answers to the above questions (which has huge impacts on the final cost of the product in the life cycle of the product), the attractiveness of LEDs cannot be correctly I assessed. AND, unless LEDs are 99.9999% reliable, LEDs are still an unattractive option financially, unless you get product-lifetime guarantees with free replacements with your purchase. Environmentally they seem like a good option (dependent on reliability vs. alternatives)
I will blog about your incompetence @ http://www.barelyadraft.com
You seem to have missed the point that ... I wasn't making a point against the OP. I was merely saying "they are actually banned already" in some places as a response to the OP's "I hope they don't ban them".
That is, I wasn't arguing against the OP, just adding to it with some information as an aside. The OP's points are of course still completely valid.
LEDs :
I understand why you say this, however I must disappoint you, it is not correct. It is also very easy to dimm a CFL. For a retrofit LED lamp (thus in the shape of a incandescent bulb), you have to add as much electronics to dim the LEDs as you would need to dim a CFL lamp.
Technically, dimming a CFL is as easy as increasing the frequency of the oscillator that drivers the CFL tube. The only issue is the TRIAC dimmer in the wall that does not like the low power of the CFL lamp (or LED lamp). Translating the dimmer position to the oscillator frequency is easy.
The same is also true for LEDs. That is why many retrofit LED lamps are also not dimmable (there are dimmable retrofit LED as well!).
As soon as we get rid of the old fashion 2 wire TRIAC or transistor dimmers, we can dim CFL and LED easily, and safe even more energy in the end because we do not have to dissipate extra energy only to keep the dimmer happy.
Those bulbs are still three times less efficient than CFLs, not 30% but 300%. And if you believe that "a better and more efficient technology will win on its own merrit[sic]", remember you are talking about a world in which even 90% of the inhabitants of the developed countries are incapable of understanding a simple efficiency calculation. Sometimes people are so incapable of making a rational decision that you have to do it for them.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
I bought some 1.5W LED bulbs for £2 each to replace 50W halogen bulbs. They're now about 18 months old, and still work, but they are noticeably dimmer than when I first installed them.
I expect the problem will be solved (if it hasn't already with less-cheap bulbs), the same happened to the early CFLs 15 years ago.
Still, without getting really expensive, there isn't much homeowners can do about dirty power, except scream uselessly into the brick wall known as the power company. New lighting technology is going to have to cope with this situation.
Not a typewriter
Yep, good thing all that heat just comes out of nowhere or you'd be wasting lots of energy in the form of heat. Oh wait...
Halogen gives high quality lighting but still has very poor efficiency compared to flourescent or LED lighting. Flourescent and LED are average to poor quality of course, but they all have their advantages and disadvantages.
Halogen is sort of the Corvette of lighting - not the most inefficient but far from "green."
"When information is power, privacy is freedom" - Jah-Wren Ryel
Wikipedia says: "When used for heating a building on a mild day, a typical air-source heat pump has a COP of 3 - 4, whereas a typical electric resistance heater has a COP of 1.0."
So, yes, contrary to popular belief, resistive heating is a terrible waste. Burning the coal in a potbelly stove would be a little better then burning it in a power plant to generate electricity to transmit (with losses) over power lines to heat a wire near your ceiling. But using it to drive a refrigeration cycle would be a far better use of the energy.
> The study uses the assumption that LEDs last 2.5 times longer than CFLs, and 25 times longer than incandescents.
I'm wondering whether they're using actual longevity measurements or theoretical numbers. The numbers above imply that CFLs last 10 times longer than incandescents, and being a consumer of both, I have not found that to be true. Moreover, although I have not invested in LED lighting yet, I note that it is rare to see an LED traffic light that doesn't have several LEDs blown out or flickering wildly.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
We will know we're reaching the limits of computer technology when using a computer as a space heater no longer seems like a clever idea. A computer should only use as much energy as it takes to flip the output bits plus a little extra to make it happen faster than the age of the universe.
{...} the tomatoes growing in the closet use.
Tomatoes. Yeah right!
Tomatoes ?!?
I didn't knew you could smoke *these*.
{runs quickly to the nearest groceries store}
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
I don't understand why this "it has not been proven whether higher manufacturing energy costs kept the new lighting from offering a net gain" argument has any traction.
It's simple economics: Energy costs money and nobody in the manufacturing supply chain is going to provide free energy. So assuming everyone is making a profit (or breaking even at least) then the price the consumer pays must cover the cost of the energy used in manufacture and transport.
So if the end consumer realizes a net saving at the end of the product's life then then it's a genuine net gain.
(I am assuming here that energy prices are in the same ball park the world over and have the same fossil fuel vs renewable ratio: a crude assumption but I think sufficient for this argument).
If you compare the best-of-breed tungsten with the best-of-breed CFL, the factor is about 3.3. That factor of 5 (I remember when it used to be 7) is derived from a comparison with a rather poor tungsten bulb (eg 40W, which are far less efficient than 100W).
I looked at what's available now in the shops:
Best Tungsten: 105 W in, 2100 lumen out.(*)
Best CFL: 18W in, 1200 lumen out.
Efficiency difference: factor of 3.3
(*) This is the Philips "Halogen Energy Saver -30%", which also lasts 2000 hours. I'm writing this in the UK; if it were the USA, the lower mains voltage acts even more in Tungsten's favour.
In addition, Tungsten bulbs:
* Give a much better light: full spectrum, better colours, warmer, more flattering to females, and not cold/depressing in wintertime.
* Run at (virtually) full efficiency from start to end; whereas CFLs need to be replaced after 6 months as they age.
* Give out waste heat, but this is still offset against the heat you'd otherwise burn natural gas to get; electricity is potentially
green (Nuclear), whereas gas never is; also the waste heat is usually in the same room that you currently occupy, rather than
around the entire house.
* Run at a power factor of 1.0, whereas CFLs are inductive, wasting a lot of energy in transmission and generation. (the consumer isn't directly metered for this, but it pushes up the price of electricty in general).
* Could be improved further if we combine the halogen technology (in the Philips bulbs) with the Dichroic technology (used by Osram) to reflect IR back to the filament.
So, yes, there is a slight figure of merit for fluorescent bulbs, but it's pretty small.
Assuming you are in a country that has Home Depot stores: http://www.homedepot.com/webapp/wcs/stores/servlet/Search?keyword=led%2Blightbulb&langId=-1&storeId=10051&catalogId=10053
Stop breaking light bulbs. Of ANY kind. Seriously.
I have never broken a light bulb. I have never seen one broken outside of abuse. I'm sure it can happen. But this strawman in a glass house is getting really old.
Handle things made of glass with care. Gently hand tighten (no breaker bars or torque wrenches needed). Lights come with protective covers, it's okay to use them. If you can remember the last time you broke a bulb then I hope you install them for a living or you are buying cheap crap or are doing something wrong.
So it is winter where I live. Normally the heat from all my incandescent lights heat up my place a bit. This is where a lot of the waste is of the incandescent lights.
Most of the lights I have are now CFL. So while it is true the CFL is using less power, am I not compensating by using more power at my electric furnace?
Does the net power difference (savings) take into consideration that fact?
I remain confused. A few decades ago was the garbage crysis, then the pollution, then the recycling, then the fuel, then the electricity.
So let's try to swarm around this thing.
I shouldn't buy gasoline cars, because they pollute. I should buy electric because they don't. But I should save electricity.
I should recycle my lightbulbs because the glass is reused to make lightbulbs, and there's a whopping teenie weeny amount of material in incandescent bulbs in the first place, and it's all recyclable. But I should save energy
and buy CFL's. But I shouldn't use them because you need a hasmat team to clean your home for two weeks if you drop one and the mercury breaks. Oh, and even more modern lightbulbs use computer chips and chemical
coatings and produce about 100 times the amount of garbage as old lightbulbs.
Oh yeah, and they all produce way less light. Sure I can work by a CFL, or and LED, but they are just crap light to an incandecent. And just try to take any half-way crappy product photography, and see just how many CFL
or LEDs it takes to light your box.
Above me right now are 12 lights in the ceiling. Guess which one is a $60 LED? That's right, the one producing a very bright light in one teeny tiny spot directly beneath it -- on the floor. Whoopy shit.
And guess why there are 12 of them? That's right, because all of the others are CFLs.
No worries, there's a floor-lamp. A single 120W incandecent has no trouble filling the room.
LEDs are brighter because they are always focused -- I've yet to see one that's omnidirectional. How many flashlights does it take to fill the room -- one cone of silence at a time.
I went all CFL a few months ago and now, my house is lighted like a Bourne Identity fight scene in an Eastern European stairwell.
I can hardly wait until incandescents are banned.
Or like the J.J. Abrams Enterprise Bridge
-Darkshadow (There was a thing called Heaven; but all the same they used to drink enormous quantities of alcohol.)
That in my bathroom I have had to replace my flourescent bulb 2 times now over a period of 3 yrs. But my incadescent bulb has remained.
So much for longer lasting.
I replaced two 60W incandescents in my computer room with two 23W "100W equivalent" CFLs. I expected to save a lot of power while increasing the light output from 120W to 200W equivalent. Instead I find that the lighting is dim and creates a depressing environment in the room. I couldn't conceive of replacing all the bulbs throughout my house. This leads me to believe the energy equivalence is a bunch of hype at best, and outright dishonesty at worst, and that efforts to outlaw incandescents are severely misguided and premature. Switching to CFL represents a quality of life reduction. I'm hoping LEDs ultimately turn out to be a better solution.