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Power Earth Technology

CFLs Causing Utility Woes 859

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."
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CFLs Causing Utility Woes

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  • by iamacat ( 583406 ) on Wednesday April 08, 2009 @05:57PM (#27510371)

    CFLs wattage is significantly less than half of incadecent wattage. So, while this is an additional plus for LED lighting, this is still the most economical solution available otherwise.

    In any case, regular florescent lighting was in use for decades and nobody found it less efficient than any alternative.

  • I'm still confused. (Score:5, Informative)

    by Anonymous Coward on Wednesday April 08, 2009 @05:57PM (#27510377)

    28 Watts of "Apparent Power" (CFL) versus 50-100 Watts of real power. (Incandescent) Help me understand how we are still not getting a net gain, and why I should care about this?
    Is it:
    A. I'm saving money at the expense of the power grid.
    B. I'm still using at least 50% less wattage than I was before.
    C. My lights never burn out anymore, and my only major worry is taking care not to break the reasonably tough bulbs since they contain mercury.

  • Re:B.S. (Score:4, Informative)

    by seanadams.com ( 463190 ) * on Wednesday April 08, 2009 @05:58PM (#27510409) Homepage

    The utilities might not like to carry the extra amps on their lines, but that isn't the same as them having to generate more power.

    You are absolutely wrong. The additional current increases the resistive losses on the transmission lines. Hence for a lower power factor, more energy must be generated to deliver a given amount of watts.

  • Re:Summary is wrong. (Score:5, Informative)

    by seanadams.com ( 463190 ) * on Wednesday April 08, 2009 @06:02PM (#27510461) Homepage

    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).

    Sort of... the lower power factor means higher losses in transmission. So they don't have to generate the entire 28W, but they do have to generate more than the "apparent" load to compensate the additional loss in transmission.

  • by wealthychef ( 584778 ) on Wednesday April 08, 2009 @06:03PM (#27510473)
    IANAEE, but from wikipedia:
    Due to energy stored in the load and returned to the source, or due to a non-linear load that distorts the wave shape of the current drawn from the source, the apparent power can be greater than the real power. In an electric power system, a load with low power factor draws more current than a load with a high power factor for the same amount of useful power transferred.

    FTFS:
    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.'

    But the real power is never greater than the apparent power, so there is something very screwy in the summary. Probably the summary meant the "apparent" load was twice that implied by their wattage. That is, if you actually measured the volts time current flowing, you'd find it to be 28 VA, but for whatever reason, it only "uses" 13 "real watts."

  • Stopgap (Score:3, Informative)

    by Locke2005 ( 849178 ) on Wednesday April 08, 2009 @06:04PM (#27510481)
    Compact Fluorescents are only a temporary solution until we get cost-effective LED light bulbs [ccrane.com]. They are available now (even at Costco). Which means pretty soon they should actually make sense to use. Right now, they are still a little pricey, despite lasting 30 times longer than incandescents. Plus, those "environmentally friendly" CFLs contain mercury... just what we need more of in our landfills!
  • Re:B.S. (Score:3, Informative)

    by fuzzyfuzzyfungus ( 1223518 ) on Wednesday April 08, 2009 @06:05PM (#27510501) Journal
    He is wrong; but the summary is also wrong: "The bad news: the utilities have to generate the equivalent of 28 watts" is not correct. As you say, 13 watts consumed + transmission losses on ~28VA means more energy than does 13 watts consumed +transmission losses on ~13VA. TFS, though, seems to be under the impression that apparent power is 100% consumed, rather than just subject to transmission losses.
  • Re:Still... (Score:5, Informative)

    by eln ( 21727 ) on Wednesday April 08, 2009 @06:05PM (#27510505)

    I agree, and even if the article is 100% accurate, you are still saving more than 50%.

    About 3 months ago I decided to switch over, and since then I've been slowly replacing all my incandescents with CFLs as they burn out. I was initially afraid of the flicker factor, since the flourescent tubes in my laundry room flicker like crazy and give me headaches when they are first turned on, especially when it's cold. However, I haven't really noticed any flicker with the CFLs so far.

    As for the lifespan, it is kind of silly how they report it (9 years, but only if you use each bulb less than 3 hours a day), but it's still longer than an incandescent.

    So basically yah, CFLs aren't the best we can do, but they're the best affordable replacement for incandescents we have so far.

  • Re:Still... (Score:4, Informative)

    by peragrin ( 659227 ) on Wednesday April 08, 2009 @06:07PM (#27510529)

    The incandescent in my bedroom light has been replaced twice in 6 years. I put in a 100 watt bulb and dim it 75% and this one is lasting almost as long as the CFl's.

    The trick with CFL's if you want a good one is you have to pay for them. you can't buy the $2 home depot specials. however if you spend more than $3 per lamp you will lose money. on energy saved versus dollars spent for the same light.

  • Re:That pretty bad (Score:5, Informative)

    by gbjbaanb ( 229885 ) on Wednesday April 08, 2009 @06:15PM (#27510649)

    sure they are that bad. A CFL draws roughly half the power it emits as light (if you see what I mean) giving a power factor of about 0.5, which is dreadfully inefficient.

    However, power factor refers to the current load, so a CFL of 0.5 will draw twice the current, but it will still be drawing the wattage it claims. So yes, they need to shove more current down the wires, but its costing you the rated watts.

    Also, the CFL will be rated at 13W, the comparable IL at 60W. even if the CFL is drawing twice the current, its still using a quarter of the energy used by the incandescent.

    Put it another way, a 60W incandescent draws 0.5 amps (60W/ 120V = 0.5). A 0.5 PF CFL at 13W draws 0.2 amps (13W/120/0.5)

    I doubt its a serious blow against CFLs, just a serious attempt at FUD to talk up ILs, or an attempt to justify power companies charging you more (as that 13W lamp still costs you for 13W even if the power company has to deliver more).

    Here's an less sensational article [iaeel.org] about the problem.

  • Arrgh! (Score:5, Informative)

    by goodmanj ( 234846 ) on Wednesday April 08, 2009 @06:15PM (#27510653)

    As someone who teaches physics for a living, the Slashdot summary is making my eyes bleed.

    Now EDN reports they may use more energy than claimed

    Argh! No, they don't use more energy, but they do have higher "Load".

    Here's the analogy. Every day, hundreds of thousands of people travel in to Boston. Does that mean we need to build hundreds of thousands of new apartments every day? No, because every day they all leave again: they're commuters.

    Boston needs to design its roads to handle the rush hour traffic, but it doesn't have to build a ton of houses for them to stay.

    Energy in a low power factor circuit is like a commuter: it flows into the device, then it flows back out again. The utility company needs to design its power lines to handle the rush hour flow, but you're not "using up" the energy in any sense.

    TFA talks about real wasted energy caused by this "rush hour" flow, but transmission losses are a small fraction of total energy use. This isn't going to affect the overall efficiency of CFLs.

    TFA talks about requiring "power factor regulation" on CF light bulbs. This is a pointless extra expense. While CF bulbs make life harder for the power company, other common appliances act to counterbalance the effect, so averaged over an entire city, the problem is mitigated. But even when it's not, the *power company* can always install devices (giant capacitor banks, typically) which compensate for the power factor. There's no need to build more power plants.

    So what it comes down to is, CF light bulbs don't use more energy than they claim, but they do generate higher peak loads. We can force either the consumer or the power company to install equipment to compensate for this.

    I say, "Hey power company. I'm paying you guys to deliver me some kilowatt-hours. Nothing in my contract limits how I suck up those kWh: if I do it in a way you're not expecting, it's your job to install equipment to handle it."

  • by goombah99 ( 560566 ) on Wednesday April 08, 2009 @06:16PM (#27510657)

    Since a CFL consumes a exactly constant amount of power it shoul dbe trivial to put in an inductor and capacitor in the package to exactly compensate for it.

    Moreover if the power factor is really 0.5 then it seems like just having two of these running in quadrature ought to null the power factor back to 1.

  • Going a step further (Score:3, Informative)

    by hwyhobo ( 1420503 ) on Wednesday April 08, 2009 @06:21PM (#27510729)

    While I am happy with the savings from using CFLs, I would not hesitate to spend a little more up front to get even more savings and greater longevity from LED lights. Does anyone have solid data on how the three types differ? For example, if to produce the same amount of light incandescent uses 100W, CFL uses 60W (including power losses), how much would LED require? Also, of the above three light sources, if the incandescent lasts 6 months, CFL lasts 10 months, how long would the LED last?

  • Re:Summary is wrong. (Score:5, Informative)

    by Anonymous Coward on Wednesday April 08, 2009 @06:24PM (#27510753)

    That is correct, but it overstates the magnitude of the problem. If the PF is 50%, then the utility has to supply (transmit) twice the current. That extra current is not used up by the load, but it does translate into additional transmission losses.

    T&D losses for the whole grid average about 10-15%. However, local T&D (from the substation) is much lower, because there is much less distance involved.

    Let's conservatively say that the local T&D loss is 5%. Then the 13 watt bulb consumes 13 watts at the load. In addition, it is responsible for the dissipation of an additional 13 * 0.05 = 0.65 watts due to the additional line losses from the extra current being supplied.

    So now your 13 watt bulb uses 13.65 watts.

    Big.

    Fraking.

    Deal.

    Nothing to see here. Please move along.

  • by Sycraft-fu ( 314770 ) on Wednesday April 08, 2009 @06:24PM (#27510759)

    It is possible the bulbs are just old/damaged and new bulbs would do better but most likley it is the ballast. Old ballasts were mechanical and operated at line frequency. This means that you are going to get flicker at 120Hz since it crosses the null 120 times per second. That is noticeable to some people.

    New ballasts, including those in CFLs, are electronic. They cycle at a much higher rate, generally in the realm of 30kHz, because that's more efficient. That also gets rid of visible flicker, of course.

    So what you need to do is replace the ballasts. You can get new ones at any home supply store. Alternatively you can just replace the whole fixture, new ones will come with ballasts. Should stop your flicker, reduce your power draw, and last longer to boot.

  • by Lonewolf666 ( 259450 ) on Wednesday April 08, 2009 @06:26PM (#27510797)

    A. is true to some extent. The 28 VA will cause some losses on the net on top of the 13 watts you are billed for. But I doubt those losses are greater than maybe 1 or 2 watts. Disclaimer: I'm an electrical engineer by training, but don't work in the power grid business. So take this as an educated guess, not something I have calculated.
    B. True. With the above estimate, make it 75% less or better.
    C. Not entirely true, but good quality CFLs last pretty long. In my apartment, both the two 15 Watt CFLs I put in 8 years ago still work fine. A rather small sample but I think it gives you an idea of CFL durability.

  • Re:That pretty bad (Score:3, Informative)

    by smellsofbikes ( 890263 ) on Wednesday April 08, 2009 @06:28PM (#27510823) Journal

    It would, actually -- power factor correction isn't trivial. It's not bad for a CFL because you know that the load's fixed, but it's still a couple extra capacitors and an inductor (I'd have to model it but I think that'd work) and CFL's are *enormously* price-sensitive as they're trying to displace a cheap-as-dirt technology. I work in lighting design (in fact, I'm helping design a fluorescent ballast right now) and it's frightening how cheap many of the power supply designs are.

  • Re:That pretty bad (Score:3, Informative)

    by Hyppy ( 74366 ) on Wednesday April 08, 2009 @06:28PM (#27510831)
    It's not new. All flourescent bulbs have a power factor of less than one. It's how the ballast works. If you have a capacitor or inductor on ANY A/C circuit, it will have a power factor of less than 1.
  • by sexconker ( 1179573 ) on Wednesday April 08, 2009 @06:28PM (#27510835)

    Or value your sanity/health.

    Never break a CFL.

  • Re:Still... (Score:4, Informative)

    by lupine ( 100665 ) * on Wednesday April 08, 2009 @06:33PM (#27510903) Journal
    Since CFLs last about 5 years the break even point is way above $3/lamp. I switched my whole house, cost me $40, but now I save $15/month on electricity.
  • Re:That pretty bad (Score:3, Informative)

    by serbanp ( 139486 ) on Wednesday April 08, 2009 @06:33PM (#27510911)
    yes, it will cost much more. In your LCD display, the PFC is done by a circuit essentially identical to the one in your notebook power brick. How much are these selling for? A lot. Even if you account for a 10X price factor, the cost is still above 2-3 bucks. And the components are bulky.
  • by Rei ( 128717 ) on Wednesday April 08, 2009 @06:39PM (#27510985) Homepage

    Most people are used to "soft" or "warm" light from incandescents -- low color temperature. Most early CFLs were "cool" or "daylight" -- high kelvin temperature. Now you can get both, but "warm" (low color temperature). are more common because that's what most people prefer. Check the color temperature on the box before you buy!

    Also, if you have flicker or a buzz, or a slow startup, you got a low quality bulb. Return it and get a different brand. Or buy several and see which ones you like the best. Good CFLs don't flicker or buzz, and they start up essentially instantly. There is a lot of variety between brands and models. And quality averages way better than it used to, although there still are some bad apples out there.

    And I haven't seen any reasonably priced dimmable CFLs to test out (do you need a special dimmer?)

    I got several cases of dimmables on Ebay a couple years ago, and they work just great, on my normal dimmers. Don't remember the brand, but I could get it for you at home if you need it.

    By the way -- how many Slashdot articles (like this one) are we going to have full of people trying desperately to come up with a way to justify their decision to spend *way* more money in electricity and increase emissions because they're too lazy or stuck in their ways to merely change their lightbulbs? I mean, come on... is power factor really the best they can come up with? Really, if that's your excuse, just buy a freaking high power factor bulb. Yes, they exist, and have power factors in the 0.9 to 0.95 range. But even with low power factor bulbs -- since when is 1/4 (CFL apparent power consumption relative to incandescent) * 2 (power factor=0.5 CFL) greater than 1.0 (incandescent)?

  • by Spoke ( 6112 ) on Wednesday April 08, 2009 @06:40PM (#27511007)

    It should be normal, especially considering that Home Depot takes them for recycling and you don't seem to have to drive more than 5 miles to find one.

  • Re:Still... (Score:3, Informative)

    by jrumney ( 197329 ) on Wednesday April 08, 2009 @06:45PM (#27511065)
    The fluorescent tubes in your laundry use magnetic ballasts that work at mains frequency (60Hz, or 50Hz depending on where you live). CFl bulbs use an electronic ballast that works up in the kHz range, so you don't see any flicker.
  • by Rei ( 128717 ) on Wednesday April 08, 2009 @06:45PM (#27511071) Homepage

    Here's the problem with LEDs. Yes, LEDs have extremely high quantum efficiencies.... in the *red and blue spectrum*. There are no efficient yellow and green LEDs; it's called the "green gap". But it just so happens that's where our eyes are the most sensitive; we're insensitive to red and blue, but sensitive to yellow and green. So-called "white" LEDs are usually just blue LEDs with a phosphor coating that wastes some energy to create a lower frequency spike, enough to make it look roughly "white" (but in general they're often still blue dominated, making it somewhat of an irritating color). There are "warm" LED bulbs that make a stronger low-frequency signal with phosphors, but that wastes even more energy.

    The other main complaint about LEDs is flickering, but that's trivially remedied; good bulbs are full-wave rectified, unlike the cheapo ones that are half-wave rectified and flicker.

    The net result, however, is that LED bulbs for lighting tend to be only marginally more efficient than CFLs in terms of lumens, if that, and tend to have more irritating colors. We need to close the green gap.

  • by rolfwind ( 528248 ) on Wednesday April 08, 2009 @06:55PM (#27511193)

    Or you don't live near a Home Depot.

    http://www6.homedepot.com/ecooptions/stage/pdf/cfl_recycle.pdf [homedepot.com]

  • by dacut ( 243842 ) on Wednesday April 08, 2009 @07:00PM (#27511251)

    Wow, I had no idea this would've been taken as an anti-CFL rant. Apparently neither my viewpoint nor the article's came through in the summary, which is more that there's no such thing as a free lunch (i.e. CFLs have downsides, too.). I think the headline was regrettably chosen, though, which I took from the original article and reworded to fit in /.'s character limits.

    Bruce, you make a lot of good points. Yes, the mercury output is less than if you're on coal electricity (we're mostly hydro here). And unless lighting is the large majority of your electric bill (which it isn't for most households), the power factor of those CFLs aren't going to matter. I was surprised, however, to find that the power factor is as low as it is. I'll be happy once we have fewer integrated ballasts (which are produced as cheaply as possible). Spending an extra dollar on the ballast could improve the power factor and other issues significantly.

    However, there's one claim that is problematic:

    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.

    If you're using CFLs indiscriminately, you're applying the technology suboptimally. A rarely and briefly-used hallway light, for example, would be better served by an incandescent. The initial power surge to kick off the light will eat into your usage and savings -- very minutely, but still not the benefit you think you're getting. Which was really the point of submitting this article: we can't blindly use any technology -- CFLs, hybrid cars, wind power, etc. -- thinking that it's the perfect solution. Some thought has to be applied, and that requires information.

  • by Barny ( 103770 ) on Wednesday April 08, 2009 @07:00PM (#27511257) Journal

    It is in fact, you can make a fluro light appear to your meter to use zero power (with the right inductor/cap combo).

    Its illegal afaik in most countries though.

  • Re:Still... (Score:5, Informative)

    by Rei ( 128717 ) on Wednesday April 08, 2009 @07:00PM (#27511259) Homepage

    Some day there will be a report of all the damage to the environment being caused by discarded CFLs and people will wonder what the hell we in this century were thinking, replacing low-pollution cheap lights with mercury-containing costly electronics gizmos

    How many times does this myth have to be knocked down? It's like fighting a zombie.

    1) Coal power plants, which make up half of our electricity production, are the prime emitters of mercury in the world, and emit more, straight into the air, powering an incandescent bulb than a modern CFL would emit if you took all of its contents and vaporized them straight into the jet stream.

    2) Where were you complaining about mercury when fluorescent tubes became the standard for offices nationwide many decades ago? These use over an order of magnitude more mercury.

    3) Mercury in fluorescents is so-called "inorganic" (elemental) mercury. Most mercury emitted by power plants is "organic" mercury (mainly methylmercury, but also some dimethylmercury). Organic mercury is far more toxic.

    4) Even just throwing a CFL in the trash doesn't mean all that mercury is emitted to the environment. I could dig up the link *yet again* if I have to, but the amount of mercury released from CFL disposal is roughly along the lines of: 20% if your trash is incinerated, 3% if it's landfilled, 3% if you throw the bulb into normal glass recycling, and a small fraction of a percent if it's treated as hazardous waste.

    Modern CFLs use a really, really tiny amount of elemental mercury -- about the mass of ten grains of salt. What's going to be the next scare over -- the radioactive americium in smoke detectors?

  • by Ungrounded Lightning ( 62228 ) on Wednesday April 08, 2009 @07:02PM (#27511287) Journal

    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.'

    Oh, good grief!

    It's a LEADING power factor, a load with a large CAPACITIVE component.

    The main problem with electric grids is all the INDUCTIVE loads with a LAGGING power factor - like big induction motors. The power company has to hang capacitors (or other power-factor correctors, such as certain synchronous motors) all over the grid to "generate" the VARs that are "consumed" by the inductive loads. So until they're responsible for more reactive power than the motors, transformers, and such the compact fluorescents will be HELPING the power company.

    Neglecting harmonics (which are a whole 'nother can of squiggles) the main issues for power transmission are:
      - "Real Power" ("watts" = volts times amps) (current is in-phase with voltage).
      - "Reactive power" ("VARs" {"volt-amps reactive"} = volts time reactive current) (current is 90 degrees out of phase with voltage, either "leading" or "lagging").

    Cycle-by-cycle:
      - Real Power generation must match consumption.
      - Reactive Power "generation" (current into a load leading voltage) must match "consumption" (current into a load lagging voltage).

    Whatever mismatch occurs in the field will be supplied by the generators and transmitted across the grid to the load. The Reactive Power (or "imaginary power" - because it's times sqrt(-1) when you use complex numbers to represent real and reactive at once) represents current thrown back-and-forth between capacitances and inductances. But when it gets transmitted on the lines or generated by a rotating machine it vector-sums with the real current, resulting in a higher current magnitude.

    The losses in the lines and the generator and transformer coils are current-squared-times-resistance, and those are REAL energy losses that must be made up by the prime mover applying torque to the generator's shaft, regardless of the relative phases of the current and voltage. Also, the limit on transformer and generator capacity is heating due to current, so it's this vector-sum current that is the limit.

    The power company would like to run their generators and lines as close to power factor 1 (all the current is in-phase) as possible, to get the most out of their equipment and to minimize the resistive losses that they have to make up for with fuel.

    But most of the "reactive load" on the grid is induction from transformers and motors. So an inductive load is (arbitrarily) defined as "consuming" reactive power - thus defining a capacitive load as "generating" it. The power company buys and installs a lot of expensive capacitors (and switching equipment to turn them on and off as needed) all over the net, to "generate" much of the reactive power needs, making most regions as a whole close to resistive as possible and minimize VAR transmission and the resulting extra line losses.

    The compact fluorescents will actually HELP this. Your neighborhood and its nearby business districts no doubt has far more inductive load (from normal fluorescents, arc lights, refrigerators, fans, blowers, compressors, etc.) than capacitive load (from switching power supplies, including those in compact fluorescent and electronic "balasts" for tube fluorescents). This will continue to be true even if ALL the lamps are replaced by CFs and electronic-ballasted fluorescents. So the reactive current from your CF lamps will flow only through a small amount of wiring before canceling out that from some inductor. This means they produce virtually no wiring loss. Indeed, it will likely keep VARs from motors from being sucked across more line resistance from a nearby pole-installation or substation's capacitors or over the long-haul grid from further away, for a net gain.

  • by joggle ( 594025 ) on Wednesday April 08, 2009 @07:07PM (#27511337) Homepage Journal

    Still, as demonstrated on the Myth Busters a while back, LED bulbs can be turned on and off many more times than other kind of bulb. This can make them last substantially longer than anything else and should be factored when considering their efficiency and cost I believe.

    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 learned this from http://en.wikipedia.org/wiki/Light-emitting_diode#White_light [wikipedia.org]

    In addition, I learned why white LEDs get so hot--it's due to the Stokes shift which happens when the blue LED light is shifted to white via the phosphor coating.

  • Re:Still... (Score:5, Informative)

    by Rei ( 128717 ) on Wednesday April 08, 2009 @07:24PM (#27511523) Homepage

    A modern CFL, the low-mercury kind that's starting to dominate, has only about 3mg of mercury in it. That's about the mass of ten grains of salt. Compare that to how kids used to play with whole balls of the stuff from thermometers -- and you're worried about ten grains of salt worth, a fraction of which might have left the bulb? On top of that, it's elemental mercury, which is far less toxic than mercury bound up in organic compounds (like you find in food, or power plant emissions). And it's not a dust.

    Every so often you'll get some scare story about how somebody broke a bulb, and they had their mercury levels in the room checked and it was X times over the OSHA standards. But those standards are for chronic exposure, and we're talking about levels that fall off exponentially over time. For crying out loud, if you're concerned about tiny amounts of mercury in your body, there are a lot better ways to prevent it than worrying about CFLs. Like cutting down on seafood, or having any amalgam fillings removed from your teeth. And if you care about mercury in the environment, you should absolutely *not* be using incandescents, as coal power plants are our primary mercury emitters.

  • by Anonymous Coward on Wednesday April 08, 2009 @07:33PM (#27511633)

    And the color temperature rating for fluorescents is based on the weighted average of where its power output lies.

    That is not a color temperature. It is a "correlated color temperature". Color temperature is defined as the temperature at which a blackbody radiator emits a given spectrum. There is no temperature at which a blackbody radiator emits the same spectrum as a fluorescent bulb. Indeed, fluorescent bulbs FLUORESCE.

    These are different things, even if you want to pretend they aren't.

    Electric heat is inefficient. And electric heat in the summer means more AC. Adding extra heat to your house is overall definitely not a good thing.

    Wow, way to miss the point. I specifically said "in the winter".

  • by natoochtoniket ( 763630 ) on Wednesday April 08, 2009 @07:38PM (#27511695)

    I have fitted my whole house using ULA brand CFL lights. The box says >90% power factor. I have measured the power factor of several of these bulbs, and they have actually measured between 92% and 94%.

    And, they are dimmable. (Ok -- they don't dim as much as incandescent lights, and some of them want to flicker. But dimming doesn't destroy them immediately.)

    In the bargain, they are cheap. (At least, they are cheap in California, and on ebay from CA sellers, until the PGE subsidy runs out.)

    So, you have to pay attention to power factor when you buy anything that is not incandescent. But if you pay attention, you can still get a good deal.

  • Re:Still... (Score:2, Informative)

    by wahmuk ( 163299 ) <jlwomack61.gmail@com> on Wednesday April 08, 2009 @07:39PM (#27511699)
    I've had an entirely different experience.

    We moved into this house (built new) in July 2006. By the end of September we'd replaced every light in the place with a CFL, some 45 or so bulbs. The vanity in the guest bath has four globes and the main bath vanity has eight (it originally had eight *100 watt incandescents!). Most ceiling fixtures have two 40W equivalents, there is a 100W equivalent in a torchiere in the living room and one in the attic, and there are a sprinkling of 60W equivalents in various single-bulb fixtures in closets and stuff. We simply bought the equivalent wattage for whatever came out of the socket. There are four CFL spotlights on the corners of the house, 90W equivalent, on X-10 controllers so we can turn them on from the cars.

    Out of the whole damned bunch, I've replaced four of the globes used in the bathroom vanities and one 40W in a closet. That's it! Before we finished replacing the incandescents in the house, two ceiling and two closet bulbs and the one in the attic had already blown (one rather spectacularly) in the first month of living here.

    Nobody visiting us has ever noticed the fluorescent lighting unless they see the exposed bulb in the torchiere. The light quality is not noticeably different and we think that we're saving about $25-35 a month on the power bill. So figure it took about 8-10 months to offset the initial cost of the bulbs and I haven't had to drag a ladder out in almost three years.

    I'm sold. The only incandescent bulbs still in the house are in the fridge and the oven.

  • Re:Uh, yeah, okay. (Score:1, Informative)

    by Anonymous Coward on Wednesday April 08, 2009 @07:50PM (#27511815)

    Yes, if you have electric heat, you will not notice a savings in the winter. You save in all other scenarios.

  • Re:Still... (Score:5, Informative)

    by Rei ( 128717 ) on Wednesday April 08, 2009 @07:56PM (#27511905) Homepage

    The vast majority of my electricity usage is not from light bulbs, despite what most pro-CFL people would have you believe.

    What an amazing discovery! So, you're telling me that I can change how much money my lightbulbs are costing me to run simply by wasting power or not wasting power elsewhere?

    (Translation: Please, be serious here; the cost to run your bulbs is independent of where you waste power elsewhere.)

    Let's say I save $4/month after I spend $40 on the bulbs.

    Let's say I live 100 years by eating more sunflower seeds. Now let's decide what to do with those 100 years.

    (Translation: No, pulling numbers of a hat doesn't count as doing the math).

    You're really going to make me do this again, aren't you?

    75W bulb -> 19W CFL = 56W difference
    56W * 3h/day * 0.001kWh/Wh * 365.24 days/year * 0.11 dollars/kWh = $6.75/year

    Multiply by however many bulbs you'd like. Note that we're not counting the contribution to AC/heating (which nets notably worse for incandescents).

    Oh, and if your answer is, "Well, perhaps that'd justify my living room, but not Room X, because I don't use the lights in there that often" -- well, then they won't burn out that often either, now will they?

  • by vlad_petric ( 94134 ) on Wednesday April 08, 2009 @08:00PM (#27511951) Homepage
    The amount of mercury in an average person's mouth (because of amalgam fillings, still widely used) is far larger than in the lightbulbs in one's house.
  • by Anonymous Coward on Wednesday April 08, 2009 @08:06PM (#27512001)

    Electric heat is inefficient

    Can you elaborate on that? Electric heat is virtually 100% efficient; everything from an incandescent bulb that isn't light, is heat.

  • by nodrogluap ( 165820 ) * on Wednesday April 08, 2009 @09:42PM (#27512727) Homepage

    Also, there's the whole cold-weather thing. Traditional fluorescent tubes will start up in the garage for me, provided it's over 0F or so. Not so for CFLs; I went back to incandescent.

    I was on the board of our rather large condo complex and wanted to replace the 100 or so incandescent bulbs outside with CFLs but was afraid of the cold factor (it gets to -40 sometimes where I live). So, I took four brands of CFLs and did a controlled experiment: stick two of each brand in the deep freeze overnight, then quickly screw them into sockets to how well they light up. GE and Sylvania 's ballasts punked out, even after warming up. The only brand that worked completely was Globe, the cheapest of the bunch, so don't always go by price. We switched the bulbs in 2005, and haven't replaced a single one yet. They are controlled by photo sensors, so on and off once a day, with no hiccups even in the cold...

  • by djtack ( 545324 ) on Wednesday April 08, 2009 @10:35PM (#27513093)
    This was "busted" by MythBusters: http://kwc.org/mythbusters/2006/12/episode_69_22000_foot_fall_lig.html [kwc.org] And another article from Lawrence Berkeley: http://enduse.lbl.gov/info/LBNL-45862.pdf [lbl.gov] (scroll down to myth #3).
  • by magamiako1 ( 1026318 ) on Wednesday April 08, 2009 @11:12PM (#27513337)
    #1. The truck itself might be more efficient for the weight, but do you really need to burn all of that fuel to carry your ass around? I'm not arguing against having the truck for when you need to carry heavier loads, but for a regular human being you really don't need all of that weight. In gas used per mile, the Prius destroys your truck and it still carries you around. You're saving money by using the Prius unless you're carrying heavier loads that the Prius cannot carry.

    #2. My fuel can works fine, though I haven't researched this one so I'll get back to you.

    #3. The mercury amount in each of these bulbs is inconsequential. Think about it. For many decades we put thermometers in our mouths that used a SIGNIFICANTLY LARGER amount of mercury. The amount of mercury in any of these bulbs is really nothing to worry about. And while light bulbs do break, the crap spewed out about the mercury content is really pointless. At the end of the day, using them will save you money at pretty much no cost to you--even if they break.

    #4. Use less toilet paper and you won't clog these lower flowing toilets. I don't know what to tell you. I've used low flow, regular toilets, and high powered toilets. If you're that backed up that your toilet gets clogged from your shit alone I think you really should see a doctor.
  • Re:Still... (Score:5, Informative)

    by Rei ( 128717 ) on Thursday April 09, 2009 @12:26AM (#27513821) Homepage

    Most of the bulbs in my house are 60W, not 75W, and I'm paying $0.09/kWh, which puts it at $4.04/year

    Assuming you use them only for a mere three hours a day and don't count the dollar-or-two-per-incandescent-bulb contribution to your AC costs.

    each bulb costs $2.50, remember

    And incandescents are free?

    Let me say that again: a single CFL burn-out changes my total yearly savings from $1.54 ($4.04 - $2.50) to -$0.96!

    So, you live in a world where incandescents are free and you only use your bulbs for an average of a mere three hours a day, and incandescents don't increase your cooling costs, and despite only three hours of use per day, your bulbs burn out in six months. Right.

    I live in the real world, which is a very different place. I've used CFLs for about three years now. The whole house has been on CFLs for at least two years. I've taken burned-out bulbs to the dump once before -- six or so of them, tacked on to another dump trip. I just checked my bag of bulbs that have accumulated since then. There are three bulbs in it. I'm going to go ahead and do a bulb count in the house for you: 4 in the downstairs bath, one in the mud room, 11 in the master bedroom, 1 in the stairwell, 3 in the living room, 3 in the dining room, 2 in the kitchen, 3 in the upstairs bath, 2 in the guest room, 3 in the library, and 3 in the computer room, for a grand total of 35 bulbs. 2-3 years. 9-ish dead bulbs. You do the math. Oh, and a good portion of my bulbs are on dimmer switches.

    Oh, and the headaches? There's a reason I brought them up. You see, effective cost is a function of more than just monetary cost...

    Mmhmm. And I have a friend who insists that as soon as she sees a CFL, she gets migraines. After getting evidence to the contrary (by virtue of how she didn't get migraines at my house, which she didn't know had CFLs), I secretly switched most of the bulbs in her house to modern CFLs while she was in the hospital (i.e., not the old flickery magnetic ballast ones) without her knowing about it to see if she'd notice. Guess what? It's over a month later, and she hasn't noticed. They're still there. Nor has she gotten a migraine (I'd know, because she calls us to take her to the hospital to get a shot when it happens).

    She's hardly the only one I've had that experience with. I've had half a dozen people tell me that they can't stand CFLs who were shocked, when visiting my place, to learn (after being in my house for several hours) that all my bulbs are CFLs.

  • by Anonymous Coward on Thursday April 09, 2009 @12:36AM (#27513913)

    Per CBS:
    1 kg of tuna - a huge amount for a meal - will have between .04 mg (typical canned stuff) and .68 mg (albacore) of mercury.

    Parent's assertion of 1mg is FUD

    Mercury in the CFLs is also FUD (how often do you shatter these bulbs ffs)

  • by marvinglenn ( 195135 ) on Thursday April 09, 2009 @12:55AM (#27514019)

    It is in fact, you can make a fluro light appear to your meter to use zero power (with the right inductor/cap combo).

    No, you can't.

    There are two different types of power factor. One is related to the phase of the current being shifted from the phase of the voltage, the other is related to the shape of the wave if you plot the current.

    The first type, which is the type that most people are familiar with, can be corrected with inductors or capacitors. This is often done for induction motors.

    The second type of bad power factor is often due to rectifiers feeding a capacitor... your basic AC to DC conversion. The current only flows when the voltage on the AC side exceeds the voltage on the DC side. Thus, you get spikes of current centered around the peaks of the AC voltage. The phase is correct, but the current waveform is not sinusoidal. This cannot be simply corrected by inductors or capacitors.

    As a side note, this is the bad power factor that many computer power supplies suffer from.

    More complex switching supplies can overcome this issue. I've usually seen it referred to as a "power factor corrected" supply. They cost more because there are more parts in it. Thus, you don't see them in cheap CFLs.

    IAAEE (I am an Electrical Engineer)

  • by alienw ( 585907 ) <alienw.slashdotNO@SPAMgmail.com> on Thursday April 09, 2009 @01:07AM (#27514115)

    No, that would be an urban legend. Electric meters don't care about power factor, they measure real power. Also, keep in mind that modern electronic meters have a lot of features to detect tampering. So if you try to play games with the meter, the utility will know about it.

    The real problem with CFLs is waveform distortion. They use rectifiers, which draw power at the peak of the cycle. This creates nonlinear currents, which cannot be fixed simply by adding inductors. If the lamps had a purely capacitive power factor, the utilities would love them, since that would help balance out the loads from various motors (which are very inductive). Also, this problem isn't unique to CFLs. Light dimmers cause exactly the same problem with incandescents, too.

  • Re:That pretty bad (Score:3, Informative)

    by smellsofbikes ( 890263 ) on Thursday April 09, 2009 @01:33AM (#27514295) Journal

    You may be right, but I'd like to see that IC. Even with just a CFL, that IC would have to manage about 13 watts actively, which is possible but difficult, especially at 110V (here) or 220V (there.) There aren't many silicon fab processes that like combining good logic, 270V peak-to-peak swings, and integral fets with low rds(on) necessary to make the whole works run.
    Step up to a motor, where you're talking 1000W, and you have a very serious heat dissipation issue even with phenomenal efficiency. I can certainly imagine a $0.99 PFC controller that's switching an external FET through some external caps and inductors, but generally that kind of work is primarily the domain of big through-hole discrete components.

    And yeah, separating the ballasts from the tubes is a good idea. What's the point getting a tube rated for 4000 hours when the electrolytics in most ballasts aren't going to last 200 hours? Actually, we're seeing a lot of the ballasts we're playing with (other companies' designs) have failures in the very front end, the ac-dc conversion part, either from failed rectification elements or blown-out transformers. The tube's the longest-lived component by probably 2x.

  • There is no problem (Score:3, Informative)

    by thsths ( 31372 ) on Thursday April 09, 2009 @03:13AM (#27514805)

    The original submission is written by an idiot. Power factor is the ratio between real power to apparent power - notice anything? Indeed, apparent power does not require any energy to produce, it can be created endlessly from passive compensation devices. Yes, it is an annoyance for the utility providers, because they has to do this compensation, but it is a very minor issue.

    So LEDs might be a lot nicer, but it is for other reasons:directed light, better aging, instant brightness, smaller form factor etc. And is it worth 10 times the prices? Maybe for you, but not for me.

  • by CalSolt ( 999365 ) on Thursday April 09, 2009 @05:51AM (#27515677)

    There are two ways in which electric heat can be said to be "inefficient." First, there are two ways to generate heat from electricity. You can use resistive dissipative heating, which you are thinking of, or you can operate a heat pump. Heat pumps are more common in cold climates and can reach something like 130% efficiency by taking heat from outside and moving it into the cold house- plus the 100% heat dissipation from electric losses in the pump itself. Compare this to a maximum efficiency of 100% for resistive heating alone. The downside of course is that a heat pump is far more expensive than a resistive heater.

    However, electric heating is painfully inefficient when you look at the best solution- directly burning the energy source in the home. Think about it: to get that electricity to run your electric heater, the power company has to burn fuel in a power plant. The power plant efficiency is maybe 40%, meaning the remaining 60% of the heat released during combustion gets dumped into the environment. Then, the electricity must be transmitted over the grid which is only maybe 70% efficient. That means resistance heating, though 100% efficient starting at the wall socket, is less than 30% efficient overall when considering the original energy content of the fuel. Burning the fuel to directly obtain its heat is much better than converting it to electricity to transmit it first.

  • Re:Still... (Score:4, Informative)

    by SlashWombat ( 1227578 ) on Thursday April 09, 2009 @06:35AM (#27515911)
    WRT to flicker ... CFL's generally have high frequency inverter electronics built into their bases, with the inverter frequency set between 30..250 kHz, so you will NEVER see one flicker. Crack one open, you will find a couple of power transistors, an IC, some capacitors, and a rectifier bridge.

    Slow warm up I have noticed can be very bad with cheap "no name" brand tubes, but doesn't seem to be an issue with better known brands.
  • "do we want our lightbulbs to perfectly mimic natural daylight ?"

    Yep.

    "Isn't it possibly useful for our brain to differentiate between day and night, even in well-lit environments, and regulate our biological cycles accordingly ?"

    Our brains differentiate between day and night by the darkness/brightness of our environment. Making it lit with light of a different tonnality just stresses you.

    And, by the way, ther is no space between the sentence and the question mark.

  • Re:Still... (Score:3, Informative)

    by MightyYar ( 622222 ) on Thursday April 09, 2009 @09:35AM (#27517311)

    Yeah, I should have mentioned that I don't put much stock in the Consumer Reports tests. The sample size is laughable: 10 bulbs... you can't even calculate a decent standard deviation with that, let alone account for different lots. Also, the bulbs currently in their lifetime tests are the ones that were available over 6000 hours (250 days) ago... they might have changed the bulbs since then.

    I think all of these bulbs suck in the quality department - my n:Vision experience is similar to your GE experience. I'm done with n:Vision, especially since they wouldn't honor their warranty without a receipt even though they have a lot number right on the side of the bulb and know very well that it wasn't manufactured more than 7 years ago.

  • by hendric ( 30596 ) on Thursday April 09, 2009 @10:59AM (#27518495)

    Basically, the components inside the bulb "borrow" some additional power and give it back to the utility. You don't see this additional power in your bill, since you get charged only for what you use. But, the utility has to still provide the capacity to give it to you. That's the non-electrical engineer way to view it. :)

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