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CFLs Causing Utility Woes
dacut writes "We've seen compact fluorescent lamps start to take over shelf space at the local hardware store. Replacing a 60 watt incandescent with a 13 watt CFL seems like a great savings, though many consumers are disappointed with the slow warm-up times, lower-than-advertised lifetimes, and hassles of disposing the mercury-containing bulbs. Now EDN reports they may use more energy than claimed due to their poor power factor. Mike Grather, of Lumenaire Testing Laboratory, 'checked the power factor for the CFLs and found they ranged from .45 to .50. Their "real" load was about twice that implied by their wattage.' The good news: you're only billed for the 13 watts of real power used. The bad news: the utilities have to generate the equivalent of 28 watts (that is, 28 VA of apparent power for you EEs out there) to light that bulb. Until they fix these issues, I'll hold on to my incandescents and carbon arc lamps, thanks."
I'm an electrical engineer and I've been saying this for years. To bad I always get modded a troll for doing so.
'Impossible' is a word that humans use far too often. -- Seven of Nine
Yes, they may consume more than they advertise, but they still consume half the power of the incandescent bulb they are replacing.
Interesting - this is a pretty serious blow to the CFL concept, and if they're really that bad, I'm surprised why it's taken this long for it to come up. Maybe it's fixable but I doubt it could be done without adding significant cost to the bulbs.
A mechanical analogy to help you understand power factor: say you have a weight on the end of a wooden stick. You lift the stick up and down and the weight moves. You are transferring energy efficiently. Now change the stick to a spring. You can still move the weight up and down but it moves a lot less for a given amplitude. Now it may seem that no energy is lost because the spring is returning the energy to the source on each cycle, but in fact it is being lost because of the resistance in the distribution line. The loss is incurred by the power company even if it doesn't appear on your meter.
Power factor is the reason UPSes are rated in volt-amps instead of watts. Switching power supplies usually have power factors significantly less than 1.0, so it's the VA that matters.
The utility does not have to *generate* the 28W of "real" power. It just
has to *transmit* it (and typically only from the local transformer to the
customer, since phase changes can be handled using capacitors when the voltage
is down-coverted the last time).
The
It's been a while since I was in electrical theory classes, but doesn't a 13 watt CFL lamp consuming 28VA of power still consume less power than a 60W incandescent bulb?
28W less than 60W ??? I would hope so or I need to start studying new math.
greed@All_Evils:~#
So because a 13W light really uses 28W you are going to stick with a lights that uses even more?
Great logic.......
Even with these issues they are still cheaper in the long run....
The lifetime advertising stuff is really a non-issue, 'old-style' bulbs have the same advertising problems.
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Consider D. Certain people have a reflexive aversion to conservation efforts of any kind, even economically rational ones, and seek to discredit them by any means available, nonsense or otherwise.
LEDs still need DC, not AC. Feed AC to an LED and you get a nice 60Hz strobe light (see also: LED christmas lights). Maybe you can't see 60Hz, but I can and it makes me want to get a baseball bat to fix it.
So you still need a power supply("ballast") that has a high PF for converting AC->DC.
Or we need to figure out how to rewire houses to have a single AC->DC conversion point, and pipe DC around to the lighting fixtures. With LEDs, that might be plausible, but I haven't done the math.
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If the customer is only billed for the 13 "real" watts used per the summary, then this is a non-issue. I paid for a 13 watt bulb advertising $x in saving on my electric bill, and I get $x in saving on my electric bill. I make my purchasing decisions based on the cost to me, not on the cost to the power company.
Great logic there... "I'll stick to incandescent 60W seeing that CFLs consume 28W and won't last longer than me".
For what it is worth, I switched to neon tubes in most of the house... a single 36W TL totally pwns a 300W setup of incandescent or halogen bulbs, more light and more accurate colours. Those can be bought for a song nowadays and they are almost instant-on. The conversion actually made me money as I was able to sell two of the previous fixtures at a flea market for more cash than all the neon kits I bought.
I also have a couple of 1.2W LEDs for the night lights in the main hall, but the electronics are quite flakey in my experience.
More likely you simply don't do well with blue/white light. The light from incandescent bulbs is yellow, and can appear more powerful because it is perceived as warmer at an instinctual level for humans who have been using fire for tens of thousands of years. The illuminating power reaching your eyes can be the same without feeling the same.
Because you have gas heat but electric AC, and you changed the bulbs in the fall?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Speaking of conscience, why is it that Slashdot is an oft-repeat offender in spreading anti-CFL nonsense? I've seen many pieces like this here.
If your utility has serious trouble with the power-factor of CFLs, they will tune the system with some additional inductance or capacitance. But they don't. Because this isn't a problem. It's the power factor for the sum of everything on the secondary of your local transformer that is a problem, and that probably ends up being close to 1.0 . Smart transformers, by the way, tune this automatically. I see them on more poles lately.
Second, the mercury issue. Which is 1/10 the mercury put out by burning hydrocarbons (especially coal) for powering incandescent lamps. Yes, the mercury from CFLs is mercury in your house, and the other kind of mercury from the generators powering incandescent lighting is just in the air you breathe in your house. And then, they take some time to start. This is a problem for some outdoor use, and tolerable for indoor use unless your home is really cold. And some of them burned out too fast, like any cheap electronics. Learn which brands don't.
It's nice that practical LEDs are coming some day. I'm sure we'll hear lots of propaganda about the arsenic and other toxic things in them, even though it's close to impossible to actually get those chemicals out of the chip, out of the plastic around the chip, etc., and they're in such small amounts that it doesn't matter anyway.
I only have one incandescent lamp left in my home, and that one is going to leave someday soon too. We are a healthy, happy family, and we're spending less and hurting the environment less. That's the reality for CFL users.
Bruce
Bruce Perens.
Timmy (he prefers to have it spelled properly thanks) would tell you that the amount of mercury put into the air and water by the coal powered power plants needed to power your incandescent bulbs dwarf the amount put into that CF bulb. CF bulbs are still a net mercury reduction. At least until we get more green power online. At which point we'll have to reanalyze.
Funny how no answer is perfect, nor stays the best answer in perpetuity. It's almost as though we're going to make value judgments and reevaluate our choices periodically.
Ever notice how the incandescent defenders love to do the math on the cost of the bulbs, but they always leave out the cost of the electricity?
Hmm, gee, I wonder why that might be....
"99 dead duelists of Dios on the wall. 99 dead duelists of Dios! Take one's ring, pass it around..."
If you dim an incandescent bulb, it lasts longer, but dimming also dramatically reduces the efficiency. Lowering the temperature shifts the whole spectrum to the infrared side, which means the bulb turns an even lower percentage of the consumed energy into light and a higher percentage into heat. The only reason why halogen bulbs are more efficient than normal incandescents is that the filament in a halogen bulb is hotter.
The energy savings of CFLs are far greater than the cost of even luxuriously priced CFLs: Let's say you replace that 100W@75W bulb with a 24W CFL. That's roughly equivalent to the light of the undimmed 100W bulb (i.e. more light than you get now.) That's 50Wh less for every hour of use. At $0.11 per kWh, you save $3 in (3$ / 0.11$/kWh) / 0.05kW = 545 hours. Good CFLs are rated for 6000 to 10000 hours, so that amounts to more than $30 in energy savings. You also save the cost of several incandescent bulbs which you would have to buy over that time.
By the way, people who dim their lights should not have any qualms about the power factor of compact fluorescents: Dimming an incandescent light has a low power factor as well. Switching power supplies also have a low power factor. PC PSUs usually have active or passive "PFC" (power factor correction) to reduce the problems which a high load with low power factor can cause.
Unfortunately this is not at all true.
Most of the poor power factor in a CFL is due to harmonics of 60Hz in the current, not phase shift.
Even if it was only phase shift, then an inductor with the required value that could also fit in the ballast of the lamp would have high resistance and high losses, and be expensive.
This seems like an obvious idea, and it is. The fact that it is not used in CFLs is due to the fact that it is not practical in any sense.
It looks like there's a few ways of creating white LEDs, including using separate red, green and blue LEDs (although this is rarely mass produced) and using near UV emitting LEDs in a similar fashion that you described, which results in a better color spectrum but with the risk of emitting UV light if there's a manufacturing flaw.
I don't see why this is such a big deal. An uncoated fluorescent bulb primarily puts out UV light. It is the coating that produces visible light, via fluorescence.
After all, I am strangely colored.
This is really fascinating and has economic impacts on power generators and utilities, because "reactive power" and "real power" are compensated entirely differently at the wholesale level.
We in the bulk electricity industry think of reactive power as a service that is needed to ensure the reliable operation of the bulk power (a.k.a. high voltage transmission lines) system. Because reactive power is generally created for reliability reasons, there's a strong sense that no individual generator of electricity should profit by providing a necessary service. Instead, the existing compensation system for the creation of reactive power is based on a generator's individualized cost of producing that reactive power with a very small markup. In contrast, generators receive compensation for real power based on the prevailing price for power set by the market (either through an organized market or via a bilateral contract. And yes, I know I'm simplifying horribly). In order words -- the profit potential when you generate real power is significantly higher than when you are generating reactive power -- though of course, the risks are also higher. As a general rule, nobody wants to be stuck holding the economic bag for having to generate more then their share of reactive power (with some unit-specific exceptions).
Further, the compensation rules within various utility footprints for reactive power vary -- generally, everyone producing reactive power is eligible to receive payment for their reactive power -- or nobody is. The Feds simply ensure that the local utility isn't discriminating by providing their affiliates with reactive power payments, while denying comparable payments to the competition (something that used to be endemic).
It's critical to remember that reactive power + real power = total output of the facility. When reactive power production goes up, real power production decreases. So the idea that these lightbulbs are eating more than their share of reactive power has significant economic implications.
I don't even want to think of what it means for reactive power reserve margins (i.e., the "cushion" that utilities are required to have on standby at all times) if the lightbulbs become even more ubiquitous. Just goes to show that when electricity is involved, nothing is simple and no good environmental deed goes unpunished.
" many consumers are disappointed with the slow warm-up times, lower-than-advertised lifetimes, and hassles of disposing the mercury-containing bulbs.
I would wager that most consumers just throw them in the trash. Sure, you're supposed to recycle them, etc., but most people don't know that and don't read the instructions. The hassle factor for most consumers is zero.
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I think your information is basically wrong. Perhaps you've been buying the wrong lights. The lumen ratings for bulbs take the human visual color response into account, so a "white" LED of 100 lumens is dumping a pretty good load of light into the green range. The color temperature on the most efficient LEDs is a hair off (looks like a welder's torch to me), but their light is as good as what you get from similarly efficient fluorescent bulbs. The LEDs I have in mind are the relatively recent CREE XRE power LEDs, that run at between 350 and 1000 mA.
If you are willing to take a minor efficiency hit, go for a quality "neutral white" LED, and you get pretty good light. I did this for the lights under our kitchen cabinets, and it is great.
You are correct that there are no efficient "direct" green LEDs, but the phosphor downconversion is no different from how it is done in fluorescent lights, and because the initial light is not confined to a small number of wavelengths, the resulting light is better looking. I initially got this information from a physicist (we were taking our kids on the same ski trip) and I later confirmed it for my own self with a diffraction grating. By-the-way, if you look at those diffraction-grating pictures, you will see that the white LEDs do indeed emit a good amount of yellow and green.
If you see flickering in your LEDs, you are using a truly cheap regulator. All the ones that I use are built around switching power supplies for efficiency, and their "flicker" is in the 10-100 kilohertz range. As far as durability goes, I have generator-driven current regulated LEDs on two of my kids' bikes and two of my bikes, and they ALL live outdoors, one not under any cover, in Massachusetts, year round. The kitchen lights are on almost continuously, since they are the most efficient lights in the house by far. Most important to long lifetime, is adequate heat sinking, and/or not over-driving the lights (they're also more efficient at lower power, even holding the temperature constant, and they're more efficient at lower temperature, which is a side-effect of lower power when you don't hold the temperature constant).
Where the heck did you get your information? If this is from lights that you've bought/used, I'd love to know which ones, so that I will never buy them by accident.
I prefer the pink gap.
Do you even lift?
These aren't the 'roids you're looking for.
The fact that reactive loads cause additional heat-related losses is usually considered uncontroversial in the land of EEs, but apparently not on /.
No doubt there are additional losses, but since the power distribution grid is something like 90% efficient, these additional losses are very small compared to the energy savings gained by using a CFL instead of an incandescent.
As an entirely separate matter, a utility's costs are dominated by capital costs,
Yes, but the article seems to suggest that to handle this peak load, you need to build more power plants, which is not true. A pile of capacitors at a local substation will correct the power factor, at a cost much less than a new power plant.
Anyway, we agree that a cheap capacitor can solve everyone's problems. You want a capacitor on the device, which the consumer would consider cheap. I want a capacitor for the neighborhood, which the power company would consider cheap. Your way reduces peak loads throughout the circuit; my way can take advantage of random capacitance elsewhere in my house or neighborhood to cancel out the inductance.
And while my "hostility towards the power grid" was just for comic effect, I do think the economy of scale favors making the power company pay for the correction.
CFLs are currently where LCD monitors were 10 years ago: the advantages are intriguing, but the quality of the current product lines is scattershot, there are some significant engineering and manufacturing hurdles left to deal with, and there are a lot of people denouncing the new technology mostly because they're afraid of change. All of which will be overcome in the next few years.
Mercury is released into the environment every year from volcanos, weathering rocks, the various industrial processes that use mercury, button cell batteries, old style home thermostats, mercury thermometers, burning of fossil fuels, dental fillings and many other sources to the tune of about 5000 tons per year worldwide. In the US about 150 tons per year is released due to man's activities.
The total amount of mercury present in all the CFLs sold in the US in 2007 was 0.13 tons. In comparison the amount of mercury released in the form of amalgam dental fillings was 35 tons per year.
The concern about the mercury in CFLs is totally irrational.
http://www.energystar.gov/ia/partners/promotions/change_light/downloads/Fact_Sheet_Mercury.pdf
The above link explains lots of misconceptions about CFLs like discussed earlier here. ...
Excerpt below:
What are mercury emissions caused by humans?
EPA estimates the U.S. is responsible for the release of 104 metric tons of mercury emissions each year. Most of these emissions come from coal-fired electrical power. Mercury released into the air is the main way that mercury gets into water and bio-accumulates in fish. (Eating fish contaminated with mercury is the main way for humans to be exposed.)
Most mercury vapor inside fluorescent light bulbs becomes bound to the inside of the light bulb as it is used. EPA estimates that the rest of the mercury within a CFL â" about 14 percent â" is released into air or water when it is sent to a landfill, assuming the light bulb is broken. Therefore, if all 290 million CFLs sold in 2007 were sent to a landfill (versus recycled, as a worst case) â" they would add 0.16 metric tons, or 0.16 percent, to U.S. mercury emissions caused by humans.
How do CFLs result in less mercury in the environment compared to traditional light bulbs?
Electricity use is the main source of mercury emissions in the U.S. CFLs use less electricity than incandescent lights, meaning CFLs reduce the amount of mercury into the environment. As shown in the table below, a 13-watt, 8,000-rated-hour-life CFL (60-watt equivalent; a common light bulb type) will save 376 kWh over its lifetime, thus avoiding 4.5 mg of mercury. If the bulb goes to a landfill, overall emissions savings would drop a little, to 4.0 mg.
EPA recommends that CFLs are recycled where possible, to maximize mercury savings.
And to that I say the same thing that I say to everyone claiming to have something which increases battery life by X-magical percent: Why isn't it EVERYWHERE yet? Also I've never seen anything but incandescent supporters make that claim, any sources?
A bullet may have your name on it but splash damage is addressed "To whom it may concern."
Also I've never seen anything but incandescent supporters make that claim, any sources?
Why is it that anytime someone questions the claims of the Green Brigade they have to be in the pocket of the status quo? Isn't it remotely possible that they are simply less credulous than the general population that believes damn near everything they read?
He mentions GE which makes both incadescent and CFL's. That would seem to imply that there are those that stand to benefit either way that are making the claims.
Why isn't it EVERYWHERE yet?
painfully obvious possible reasons:
1. Tricky to manufacture with acceptable Yields
2. Expensive to manufacture at this point
3. Not likely to be as profitable due to the Green Brigades love affair with CFLs
I thought that Slashdot was supposed to be populated by nerds that think, not cheerleaders that parrot what ever they are told.
Bureaucracy expands to meet the needs of the expanding bureaucracy.-Oscar Wilde