Posted on 05/05/2007 11:18:00 AM PDT by John Jorsett
We've been looking in to compact fluorescent bulbs (CFLs) to reduce energy consumption for lighting. Here's what we've learned so far.
Manufacturers say that a 13-18 watt CFL produces light equivalent to a 60w incandescent bulb, an 18-22w CFL is the equivalent of a 75w bulb, and a 23-28w CFL is the equivalent of a 100w bulb. This is based on the "lumens" rating on the side of the box.
In real life, CFL equivalent replacements do not seem quite as bright as incandescents, so you might end up replacing a 60w equivalent with a 75w equivalent and so forth. (The "swirled" designs seem to give off brighter light than the CFLs with a traditional "bulb" design.) But overall, CFLs reduce energy use for lighting by 60%-70%.
Color temperature makes a big difference. The lower the color temperature, the more the light resembles the "warmth" of incandescent bulbs we are all used to (that may sound backwards, but that's how it works). Not all CFLs list the color temperature. The GE "Soft White" has a pleasing, almost incandescent look, while the similarly named Sylvania "Soft White" has a cooler, harsher "fluorescent" look (although some might prefer it for truer color rendering or easier reading).
We found some Sylvania "Warm White" 13w (60w replacement) CFLs at Lowes that have very pleasing light, and their small size allows them to fit most fixtures. The color temperature is listed as 2700K (as compared to their "Daylight" CFL which is listed at 6500K and seems much "harsher".) The 13w "Warm White" CFLs came in a contractor's box of 12 for $27, which is a pretty good deal. They are rated at 800 lumens with a lifetime of 10,000 hours, as compared to a standard GE "Soft White" 60w incandescent, which is rated at 840 lumens with a life of 1000 hours.
Because of their long life and lower energy consumption, CFLs can result in significant savings over the lifetime of the bulb relative to its cost. Manufacturers are quick to point this out, with claims on the packaging of $36+ in energy savings over the life of a 14w (60w equivalent) up to $61 for a 23w (100w equivalent). Your mileage will probably vary.
Most CFLs do not work with dimmers. Manufacturers say it will shorten the bulb life and it voids the warranty. There are special bulbs that work with dimmers, but they are not widely available. If the package does not say the bulb is compatible with dimmers, it probably isn't. (Look at the fine print on the base of the bulb.) We are still looking for a local source for "dimmable" CFLs, as most of our fixtures have dimmers. CFLs are also not intended for use with most photocells and timers.
One thing that is not talked about much is that CFLs emit more ultraviolet (UV) light than an incandescent bulb, which produces virtually none. Light in a CFL starts out as UV from excited gases, and is made visible by phosphors coating the inside of the tube/bulb. Incandescent light is mostly infrared emitted by heating the filament to super high temperatures (leading some to call them "heat bulbs" instead of "light bulbs"). Most of the UV from a CFL is filtered out in the conversion, but there is still some.
Manufacturers say, however, that there is no health risk and that eight hours of exposure to CFL UV is about the same as one minute in full sunlight. But, photographs, artwork, some fabrics, and some photoreactive chemicals used in furniture finishes are susceptible to degradation from any increased levels of UV over time. So this is something to consider.
The Mercury Problem
Finally, CFL critics are quick to point out that CFL bulbs contain mercury, a highly toxic pollutant. This is true. The typical CFL bulb contains approx. 5mg of mercury. (Manufacturers are working to reduce this. Phillips is said to have developed a bulb that only has 1.5mg of mercury.) If the bulb is broken, special care must be taken to properly clean up and dispose of the remnants to prevent health risks. Further, CFLs must be recycled or properly disposed of to prevent the mercury from entering the environment. Here are the federal government guidelines for CFL disposal and cleanup.
What the critics forget to mention, however, is that coal-fired power plants are a major source of mercury pollution. Further, most of this mercury is emitted into the air, and is thus not contained or containable. Mercury in a CFL is already contained unless it is broken, and if properly recycled is fully containable.
We did some rough calculations to determine the mercury pollution impact of CFL v. incandescent bulbs. We used TVA's Kingston plant as an example. It generated 10,161,530 gross megawatts in 2005, and released 643 pounds of mercury into the environment. If our math is correct, this works out to about 0.000028702 milligrams of mercury pollution per watt of electricity generated.
Based on this, a 100w incandescent bulb operated for 8 hours per day 365 days per year causes 8.4mg of mercury pollution. An equivalent 23w CFL bulb will cause 1.9mg of mercury pollution. Assuming a five year life of the bulb, and assuming the bulb is crushed and dumped in a landfill releasing its 5mg of mercury into the environment, the CFL will cause 14mg of mercury pollution over its lifetime as compared to 42mg of mercury pollution for an equivalent number of incandescent bulbs, a reduction of 28mg or 66%.
66% sounds like a lot. But according to DOE estimates, residential power usage is about 35% of the total, and lighting in the average home accounts for about 9.4% of the energy used. Considering that about 64% of TVA power is generated from coal v. hydro and nuclear, the net reduction of mercury emissions if every TVA customer switched to CFL bulbs would only be 4.6 pounds at the Kingston plant, a 0.7% reduction. System-wide, this would be a reduction of nearly 39 pounds annually.
39 pounds doesn't sound like much mercury (even though it's thousands of lethal doses) but it's something. And multiply that for every power system in the U.S. and it adds up.
Plus, we should take pollution controls wherever we can get them. If you figure a 0.7% reduction in coal-fired household energy use and related emissions across the board, system-wide TVA emissions of NOx (nitrogen oxides that cause ozone and smog) could be reduced by 1337 tons, SO2 (sulfur dioxide that causes acid rain and harms plants and stream ecology) by 3220 tons, and CO2 (a greenhouse gas that contributes to global warming) by 735,000 tons (2005 figures). Increased commercial usage of CFL would result in even more reductions.
So CFLs won't save the planet, but they might put off its demise for a month or two.
Back to the CFL mercury problem, a couple of things need to happen right away:
• Consumers need to be educated on proper disposal and cleanup. The packages we purchased do not mention this prominently or at all. One directs you to a website. There should be prominent warnings about health risks and instructions for proper disposal and cleanup on all CFL packaging.
• Local public works officials need to incorporate CFL collection, recycling and/or disposal into their waste management programs.
• Big-box retailers who sell more than 100 CFLs per year (or some other arbitrary figure) should be required to provide on-site recycling centers.
I’ll see if I can pull some up when I get back home tonight. I’ve been meaning to identify just what they are. They look more like red-eyed birds from the wrong side of town. :)
I outfitted my house with CFLs. (1) It’s true they don’t last in lights with dimmers. A couple of hours max. (2) It looks like the lifetime of CFLs is about the same as incandescents. I’m looking at an overhead light right now with 3 out of 4 CFLs burned out.
I personally prefer the light from the CFLs, but I wonder if they save any money at all.
I thought LED’s were the answer to our illumination/power/global warming impending catastrophes???
I’m usually a lurker in these forums but I’ll throw in my two cents on CFL bulbs. I’ve been using them all over my place for a year now, about twelve bulbs in all with one burnout in a year.
My main reason for trying them was that regular bulbs were burning out on what seemed like a monthly basis, every time I turned around another bulb would blow.
So with one CFL failure out twelve in a year I’m satisfied that they are doing what I bought them for.
Oh yes, I have also seen a drop in my electric bill, which is a nice added bonus to my original reason for buying them.
The articles assumption that all electricity came from coal was clearly wrong. Thanks for taking an independent look!
Ditto that. I've had a lot of luck with CF bulbs and I recommend them highly, but incandescents still make sense in a lot of uses.
And mandates are offensive as a matter of principle.
Good question.
It seems we have a threat that may be exaggerated, mercury pollution. But some say we should accept it due to the “greater threat” that is probably nonexistent, man-made global warming. The constant in each case is that we need a government solution. That is great for government, and for the liberal/socialist press that prods them on, and for some in industry. But it is bad for the rest of us.
My view is that CFL use should be voluntary. That is number one, two and three.
Also, one might ask "big box retailers" to help with the recycling, as disposal is an issue with the technology they are offering. I'm all for giving them the credit they are due.
“My main reason for trying them was that regular bulbs were burning out on what seemed like a monthly basis, every time I turned around another bulb would blow.”
That is the main appeal they have for me.
No I do not;I buy my food and other grocery store items at low price stores like Aldi and I do have one of those Kroger cards.They must wonder how I live on the few items logged by the card.
Nor will I wait in line for 20 minutes at one gas station because their price is 5 cents a gallon less.I will pay the extra 50cents or one dollar for my fill-up and save the time.Now if there was no significant wait ,I would certainly buy the best price gas.
Incandescent bulbs can often be bought for 25 cents each during sales.They simply work well enough. I have bought a couple dozen of the CFL and been less than pleased by the light ,the radio buzzing,and the short life of those from several years ago. I do note the prices are now about a fourth of the money I wasted.
Not many people are really good at calculating total system lifetime costs and benefits.For instance,I saw a company hire a "high-powered" executive to put it back on track.....his first act was to eliminate hundreds of ordinary workers jobs,Interestingly,if you took the average workers salary,doubled it to allow for benefits and pensions,multiplied the number of workers,why the total was a close match to the new "super" executive's salary.So where was the savings?And keep in mind the employees of this company(retail) tended to spend a lot of their wages right back at the company stores.Pretty good guess the one exec didn't spend much there.So how did that benefit the store,the company,the community?
Manufacturing semiconductor require using some pretty nasty chemicals;I tried the greenish electroluminescent panels nightlights.They were fine at first,use very little electricity and the fact I found them on clearance at 3 for a dollar at Home Depot didn't hurt! Too bad the light dims over several months ;after six months in the socket they were useless.Not the years of use expected and advertised.
I am like you. I don't wait in line. You have to wait a ~1000 hours before you see the profit from CFL use, but you aren't actually standing in line.
We’re not quite warm enough to attract a lot of moths and I don’t recall seeing that variety on my screens. Now you have me curious.
One of your legacies shall be that whenever I see moths congregating on my screens I’ll think of you.
I hope I can reciprocate with moth pics when mine come along.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.