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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."
Yes, they may consume more than they advertise, but they still consume half the power of the incandescent bulb they are replacing.
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:~#
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.
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.
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.
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.
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.
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.