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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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  • Still... (Score:5, Interesting)

    by revlayle ( 964221 ) on Wednesday April 08, 2009 @04:52PM (#27510279)
    Since I have switched to CFL... none of my light bulbs has ever burned out yet for 9+ months. With incandescents, I was changing 5-6 light-bulbs a month (I live in an older house, the electric grid and the wiring in the place I live is not always ideal for traditional light bulbs)
    • Re:Still... (Score:5, Informative)

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

      • by xzvf ( 924443 ) on Wednesday April 08, 2009 @05:21PM (#27510723)
        While a little more expensive they last even longer (20 years?). They really aren't available much greater than 40 watt replacements but I've been happy with the performance. Not effected by cold and come on instantly.
        • by wjh31 ( 1372867 ) on Wednesday April 08, 2009 @05:36PM (#27510943) Homepage
          in my experiance, LED's have had a pretty high faliure rate, i got a set of 6 about 6 months ago, 2 ive had to take back to replace because they stopped working, and of the ones which are here, some are noticeable dimmer than others
        • by Rei ( 128717 ) on Wednesday April 08, 2009 @05:45PM (#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 joggle ( 594025 ) on Wednesday April 08, 2009 @06:07PM (#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.

          • by dr2chase ( 653338 ) on Wednesday April 08, 2009 @06:57PM (#27511917) Homepage

            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 [wordpress.com], 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 [wordpress.com]. 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.

            • by Anonymous Coward on Wednesday April 08, 2009 @08:22PM (#27512599)

              I've purchased LED lights for my house and was extremely disappointed with their performance and efficiency. However, as you said, the Cree XRE and other recent high power LEDs can be made into very efficient and nice looking lights. Problem is, they haven't yet - at least not that I have been able to find. As far as I have found so far, the LED manufacturers have the goods, but the light "bulb" manufacturers have not yet taken advantage of all the latest LED tech.

              There's also the typical BS found in many new industries where cheapo manufacturers take advantage of the hype and produce sub-par products at very low prices. It's an easy one in this case because one of the major points is cost. This should shake out eventually and we'll see better quality products hit the market. I just want it to hurry up.

              I hate CFLs because the ONLY good thing about them is their lower power consumption. But to manufacture them is very dirty and they have mercury in them, so they can't be disposed of cleanly either. I don't like the slow start up speed or the color temperature. I bought a few packs of CFLs before finding all this out so I'm still using them. But I will not buy any more. I'm dying for LEDs to come to the main stream.

              It's not a surprise to find that the power factor of CFLs sucks too. Again, cheapo manufacturers trying to cash in on a trend. Quality manufacturers know how to handle power factor problems.

            • by nospam007 ( 722110 ) * on Wednesday April 08, 2009 @11:32PM (#27513871)

              http://www.energystar.gov/ia/partners/promotions/change_light/downloads/Fact_Sheet_Mercury.pdf [energystar.gov]

              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.
               

        • Just put in a ton of CREE LR6s in our kitchen/family room renovation. 650 lumens at only 12 watts (a 65W floodlight replacement.) The CRI is 92 with the 2700K bulb. Power factor is > 0.95. Rated at 50,000 hours (and have a 3 year warranty if they die before then) These are great bulbs. They retail for about $100, I was able to get them for $80/per on sale.

      • by Sycraft-fu ( 314770 ) on Wednesday April 08, 2009 @05:24PM (#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.

      • Re: (Score:3, Informative)

        by jrumney ( 197329 )
        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.
      • Re:Still... (Score:5, Insightful)

        by Eil ( 82413 ) on Wednesday April 08, 2009 @07:28PM (#27512197) Homepage Journal

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

        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.

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

        by Whammy666 ( 589169 ) on Wednesday April 08, 2009 @07:42PM (#27512307) Homepage
        There is a new generation of CFLs about to be released next month from a company called PureSpectrum. They have a new ballast which fixes the power factor problem (it's 0.93!) and is instant-on and fully dimmable. It's expected to be priced about the same as the current generation of non-dimmable CFLs.

        Looking a bit further ahead, another company called Vu1 has a novel idea for a light which uses electron stimulation against phosphor to produce light (sorta like a crt). It has no mercury and is also dimmable. It's also shaped like a regular incandescent so lamp shades will fit on it. They will be less expensive than LEDs and produce much better color rendering, but they will likely cost more than CFLs.
    • Re:Still... (Score:4, Informative)

      by peragrin ( 659227 ) on Wednesday April 08, 2009 @05:07PM (#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:Still... (Score:4, Informative)

        by lupine ( 100665 ) * on Wednesday April 08, 2009 @05:33PM (#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.
        • In 1994... (Score:4, Interesting)

          by RingDev ( 879105 ) on Wednesday April 08, 2009 @05:50PM (#27511143) Homepage Journal

          My mother inlaw bought 2 CFL to use in her kitchen. They are still going strong and they are probably the most used lights in her house. She paid a fair bit for them back in 94, but I'd say 15 years of consistent power savings has long since balanced out ;)

          I've replaced all of the lights in my house with CFLs over the last 5 years. The only ones that have a slow light time are the super compact ones I got to fit in a specific light fixture. And the only 2 that have "burnt out" were due to excessive vibration (one in the garage) and another that I caught with a chunk of sheet rock while remodeling.

          And most of them are from the elcheapo 5-packs that I paid under $15 for.

          I've had no issues with flickering, the color quality is quite warm (I actually have to bring in a colder light when I'm painting, but for room lighting they are great). So even if they are sucking up 28 watts instead of 14, that's still 1/2-1/4 what I would be sucking up using 60-100watt bulbs.

          -Rick

      • Re: (Score:3, Interesting)

        by Malc ( 1751 )

        This is true. I worked from home starting in 1999, and had incandescents burning out several times per month in my office. 50 cent bulbs or cheaper, go figure. I switched them in 2000 for some Philips Marathon bulbs at $15 or $20 each. One of them was still going strong when I left it in my apartment when I moved out last year. On the other hand, some of the cheap CF bulbs I bought from Canadian Tire didn't even last six months, in places where I wasn't using them nearly as much. Maybe those old Phili

    • by goombah99 ( 560566 ) on Wednesday April 08, 2009 @05:16PM (#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.

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

      by roc97007 ( 608802 ) on Wednesday April 08, 2009 @06:43PM (#27511743) Journal

      We've had this particular discussion on slashdot before. A lot of people, including me, had initially good results with CFLs, but it seems in the last couple of years the average lifespan has decreased significantly. Speculation is that, at least with some manufacturers, they've fallen victim of "value engineering".

      My own experience: My first two CFLs, purchased in the mid-nineties, still work fine. Of the Costco eight-count blister-pack I purchased last November, only three are still working.

  • by Anonymous Coward on Wednesday April 08, 2009 @04:53PM (#27510303)

    Only if you have a conscience.

    • Re: (Score:3, Informative)

      by sexconker ( 1179573 )

      Or value your sanity/health.

      Never break a CFL.

    • by Bruce Perens ( 3872 ) * <bruce@perens.com> on Wednesday April 08, 2009 @05:40PM (#27511001) Homepage Journal

      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

      • by dacut ( 243842 ) on Wednesday April 08, 2009 @06:00PM (#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 rolfwind ( 528248 ) on Wednesday April 08, 2009 @05:55PM (#27511193)

      Or you don't live near a Home Depot.

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

  • But still... (Score:4, Interesting)

    by RabidMoose ( 746680 ) on Wednesday April 08, 2009 @04:54PM (#27510305) Homepage
    28 60, so still a good power savings. Plus, all of the CFL's I've bought in the last year don't have the same warmup problems that most of the early models had. They're not quite instant-on, but that's ok with me; I like that my bedside light comes on slowly in the morning, it's less of a shock to my eyes.
    • Re: (Score:3, Interesting)

      by Mike Buddha ( 10734 )

      I have some high power ones (replacements for 75W incandescents) that turn on instantly, but they do get brighter after they've been on for a few minutes. They don't turn on to maximum brightness. It's not annoying or anything, just something I noticed. I use them in a torchier in the living room.

  • Oh Please (Score:5, Insightful)

    by Joe7Pak ( 461962 ) on Wednesday April 08, 2009 @04:55PM (#27510325)

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

    • by Anonymous Coward on Wednesday April 08, 2009 @05:11PM (#27510605)

      The whole point is not the amount of power consumed by either bulb, but the fact that the profit-per-bulb for the utility companies is lower for CFLs than incandescent. This isn't about efficiency or conservation, its about the bottom line. Not only do CFLs use less power to begin with, some of what it does use isn't even billable. Its almost like stealing. I like it!

    • Re: (Score:3, Insightful)

      by Anonymous Coward

      The summary exhibits the type of thinking that some people use to justify avoiding alternative energy sources (not necessarily all people; I'm talking about the logic, not trying to pull this off-topic). Windmills kill birds, nuclear has radioactive waste, tidal looks bad -- therefore, we must stay with coal. That is, you're completely avoiding something that is absolutely crucial to making such a decision: the disadvantages of the current system.

      The fear of change is sometimes a useful instinct, but consid

      • Re: (Score:3, Insightful)

        by sumdumass ( 711423 )

        And your way of thinking is why most people who attempt to avoid alternative energies think your crazy.

        The problem isn't a lack of consideration to the current disadvantages, the problem is with the costs associated with the level of mitigation to the current disadvantages. Take ethanol for instance, in order to be cost effective, it requires energy from oil and coal or it costs more to make then it's currently selling for. But, when you put it directly into a car designed for it, you lose about http://www. [fueleconomy.gov]

  • Summary is wrong. (Score:5, Insightful)

    by the_povinator ( 936048 ) on Wednesday April 08, 2009 @04:56PM (#27510363) 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).

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

      by seanadams.com ( 463190 ) * on Wednesday April 08, 2009 @05:02PM (#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.

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

        by Anonymous Coward on Wednesday April 08, 2009 @05:24PM (#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.

        • Re: (Score:3, Insightful)

          by whit3 ( 318913 )

          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.

          Actually, it DRASTICALLY overstates the problem, in another
          respect. If there were only a generator, lossy transmission
          line, and load, the power factor would be important in
          transmission losses (power not billed to customer).
          That is true of some large industrial plants, and it's why
          power factor billing is used.

          It's completely unrealistic for a residential community
          running motors (refrigerator, air conditioning, blowers, etc.)
          which act as motor-generator-flywheel systems, and
          which are on the load side of the long transmission line.
          The excess current due to power factor needn't traverse
          any longer wire than the space between houses
          on your block.

          The article is deliberately slanted to be provocative.

    • Re: (Score:3, Insightful)

      by evanbd ( 210358 )

      It's not a simple phase shift. CFLs rectify the AC wave, meaning they only draw current on the peaks of the waveform. If you hook up a scope to your outlet (don't be an idiot; to all the non-EE types, don't try this if you don't know how) you can see it -- the waveform will have flatter tops than it should.

      You can put complex bandpass / lowpass filters in the line that help a lot (by reflecting the distortion back at the load) but they get mode complicated and thus expensive.

      There are lots of plausible an

  • by iamacat ( 583406 ) on Wednesday April 08, 2009 @04:57PM (#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.

  • Math? (Score:4, Insightful)

    by Narnie ( 1349029 ) on Wednesday April 08, 2009 @04:57PM (#27510375)
    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.
  • I'm still confused. (Score:5, Informative)

    by Anonymous Coward on Wednesday April 08, 2009 @04:57PM (#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.

    • by fuzzyfuzzyfungus ( 1223518 ) on Wednesday April 08, 2009 @05:08PM (#27510555) Journal
      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.
    • by Lonewolf666 ( 259450 ) on Wednesday April 08, 2009 @05:26PM (#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.

  • spectrum (Score:3, Funny)

    by Lord Ender ( 156273 ) on Wednesday April 08, 2009 @04:59PM (#27510411) Homepage

    For some reason, my skin looks, I don't know, pale green under CFLs. I'm sticking with incandescent lights in my bachelor pad. Can't look bad in front of the ladies...

  • Idea (Score:5, Funny)

    by MrEricSir ( 398214 ) on Wednesday April 08, 2009 @04:59PM (#27510425) Homepage

    I think have a great idea as to how to solve this.

    But unfortunately I'm still waiting for the CFL bulb above my head to light up.

    • Re: (Score:3, Interesting)

      by julesh ( 229690 )

      I think have a great idea as to how to solve this.

      But unfortunately I'm still waiting for the CFL bulb above my head to light up.

      I have to ask: who exactly is it that the summary claims is complaining about the heat-up delay on CFLs? My experience is that modern CFLs take no noticeable time to reach a brightness level that is completely acceptable. Did the poster only ask people who haven't tried a new lamp in the last 5 years?

  • by wealthychef ( 584778 ) on Wednesday April 08, 2009 @05:03PM (#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 @05:04PM (#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: (Score:3, Insightful)

      by Rhys ( 96510 )

      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.

  • So what. (Score:5, Insightful)

    by sricetx ( 806767 ) on Wednesday April 08, 2009 @05:14PM (#27510647)
    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.
  • Arrgh! (Score:5, Informative)

    by goodmanj ( 234846 ) on Wednesday April 08, 2009 @05:15PM (#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."

  • Weak argument... (Score:3, Insightful)

    by EvilAlphonso ( 809413 ) <meushi.slashdot@gmail . c om> on Wednesday April 08, 2009 @05:18PM (#27510675) Journal
    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.
  • Going a step further (Score:3, Informative)

    by hwyhobo ( 1420503 ) on Wednesday April 08, 2009 @05:21PM (#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?

  • by Ungrounded Lightning ( 62228 ) on Wednesday April 08, 2009 @06:02PM (#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 natoochtoniket ( 763630 ) on Wednesday April 08, 2009 @06:38PM (#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.

  • by sampson7 ( 536545 ) on Wednesday April 08, 2009 @06:51PM (#27511837)
    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.
  • What Hassle? (Score:4, Insightful)

    by afabbro ( 33948 ) on Wednesday April 08, 2009 @06:54PM (#27511865) Homepage

    " 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.

Keep up the good work! But please don't ask me to help.

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