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Lighting represents about 5-10% of a home's electricity use. In the last year or so, because of improvements in the Department of Energy's Energy Star® specification, there has been considerable improvement in compact fluorescent (CF) light bulbs. Sizes are smaller, color is better, and they are now available in a wide variety of styles and wattages.
Pros and Cons of CF Bulbs
PRO's
- Convenient. With normal on and off switching, CF bulbs enjoy a long life, with one bulb able to outlast 6-10 incandescent bulbs. You spend less time on the ladder and less money replacing burned-out bulbs.
- Appealing. CF bulbs now have rapid or instant start, no flicker and are available with a comforting, soft-white quality of light. Information on light quality, color and the myth of "full-spectrum".
- Economic and efficient. Most incandescent (including halogen) bulbs waste 90% of their energy on heat. Not so with the CF bulb, which uses 75% less energy to produce the same amount of light. You can save substantially on electricity costs by using a lower wattage CF bulb and still enjoy the same or even more, light. See the Compared to Incandescent Bulbs chart.
- Versatile. CF bulbs today are smaller than older versions. You can now find CF bulbs that are the same sizes as regular bulbs. You can also buy covered CF bulbs made especially for bathroom vanity fixtures, and reflector CF bulbs for outdoor flood lights and interior recessed fixtures. And just recently, 3-way, dimmable and high light output and candelabra-based products were added to existing product lines.
CON's
- Controls. CF bulbs are not compatible with several different types of lighting controls:
- Dimmers - Using regular CF bulbs on dimmer switches will cause the bulb to fail within days or weeks. But there are dimmable CF bulbs now on the market that can be used with any conventional dimmer switch. Dimmable CF bulbs still have some performance issues including humming, color shift, stutter dimming and only partial dimming.
- Photocells - If the photocell acts only as a switch turning the light 'on' or 'off', there should be no problem using a CF bulb. But if the photocell acts as a dimmer, gradually turning the light on in the evening or off in the morning, then the CF bulb will fail within hours or days. (See Dimmers above.)
- Timers - If the timer is a manual clock type, acting as a simple mechanical 'on-off' switch, a CF bulb will work just fine. But if the timer is electronic, there is a 50-50% chance that the electronics of the timer will scramble the electronics of the CF bulb and cause it not to start.
- Motion Sensors - CF bulbs work fine on motion sensors but we don't recommend that application because of the excessive 'on-off' cycles. Excessive 'on-off' cycles (more than 20 per day) shorten life by up to 15%.
- Light Quality. Due to much better phosphor mixing (the white coating inside the glass tubes) CF bulbs now have excellent color rendering. They also come in a range of kelvin temperatures (K) from warm yellow (2700K) to bright daylight (5000K) and several in between. But we are still hearing concerns about bluish, pinkish or greenish light hues. Make sure you buy CF bulbs with the Energy Star label for best quality.
- Warm-up Time. Regular CF bulbs take anywhere from 15 – 60 seconds to come up to full brightness. Reflector types take even longer, up to 2 minutes for some.
- Heat Sensitive. If you put CF bulbs in fixtures that keep heat trapped inside or where there is little air circulation, the excessive heat build-up will cause your CF ballast (and therefore the bulb) to fail. CF ballasts are extremely sensitive to heat and therefore need good air circulation for maximum performance.
- Different Light Distribution. Because fluorescent sources emit light differently than incandescent sources, a CF bulb with the same lumens as an incandescent bulb often seems dimmer. (See Question #11 below for further explanation.)
- CF Bulbs Contain Mercury. CF bulbs contain a small amount of mercury and so cannot be thrown away in your regular trash. For more information see Disposal of CF Bulbs.
Comparing Incandescent and CF Bulbs
Incandescent
Bulb
Wattage |
Average
Lumen
Output |
Comparable
CF Bulb
Wattage |
Average
Lumen
Output |
Yearly
Energy
Savings* |
| 25 |
210 |
5 |
210 |
$1.75 |
| 40 |
505 |
9-11 |
500 |
$2.60 |
| 60 |
865 |
13-15 |
825 |
$3.94 |
| 75 |
1190 |
18-20 |
1100 |
$5.01 |
| 100 |
1710 |
23-27 |
1500 |
$6.57 |
| 150 |
2850 |
30-39 |
1900 |
$10.07 |
| 200 |
3910 |
42 |
3200 |
$13.84 |
| 300 |
5100 |
55 |
4800 |
$21.46 |
*Using average SCL residential rate of $.08/kWh and average bulb burn time of 3 hrs/day. Savings do NOT include the avoided cost of buying 9 replacement incandescents over the life of the CF bulb.
Disposal of CF Bulbs
CF bulbs contain about 4 milligrams of mercury sealed in the glass tubing of the bulb (roughly equivalent to the tip of a ball-point pen). Mercury vapor converts electricity into light. No mercury is released when the bulbs are in use. (If a CF bulb breaks, your greatest risk is getting cut from glass shards and not from the very small amount of mercury.) For more information, visit Energy Star's web site on mercury (.pdf format)
Mercury is most toxic when it leaches from landfills into the water and then into fish. Therefore, compact fluorescent (CF) bulbs or fluorescent tubes must NOT be thrown away with your regular garbage (per Seattle Municipal Code 21.36.026). Please visit www.takeitbacknetwork.org for a list of retailers that will take your fluorescent bulbs and tubes and recycle them. The King County List is here: www.metrokc.gov/dnrp/swd/takeitback/fluorescent/ For more comprehensive information, you can visit EPA's web page on mercury.
Where do CF Bulbs Work Best?
CF bulbs now come in such a variety of shapes, wattages and bases that they can be put almost anywhere there is an incandescent.
Here are some tips for installing CF bulbs:
- Put CF bulbs in fixtures that are usually lit 2 or more hours per day
- Use reflector types in recessed cans. (Remember about longer warm-up times.)
- Use globe types in bathroom vanities or track lighting.
- Use covered CF bulb types with shades that clip onto the bulb, or in bare-bulb fixtures.
- Be careful about putting CF bulbs in enclosed fixtures. Excessive heat will cause early failure. A better option is to purchase an Energy Star-labeled fixture that is designed especially for CF bulbs. These are found in most home improvement or hardware stores and are packaged with the correct CF product included.
- If the fixture is controlled by a dimmer, timer, motion sensor or photo cell, read the previous section to see if the bulb will be compatible.
- Protect bulbs installed outside from rain and snow. Otherwise, outdoor lights are excellent applications given their common use as long-burning security lights.
Frequently Asked Questions about CF Bulbs
Q 1: Doesn't it take more power to turn a CF bulb on, than to leave it on all the time?
A 1: It is a common myth to believe that switching on fluorescent bulbs use more power than operating them for short periods of time. The initial start-up, or surge of electricity, is very small and only lasts for a millisecond. In fact, a City Light demand meter could not detect this start-up load as a measurable spike. You'll use much more energy by keeping the light on when not in use. However, frequent switching of CF bulbs does shorten life, but only if turned on and off more than 20-30 times a day. That is why we do not recommend they be used with motion sensors. The bottom line: turn off a CF bulb whenever you no longer need the light.
Q 2: I've heard CF bulbs have dangerous levels of mercury in them. Aren't we trying to get rid of mercury in our environment?
A 2: Regarding mercury - yes, CF bulbs contain elemental (metallic) mercury, but it is a very small - an average of 5 milligrams - sealed within the glass tubing. This is equal to the amount that would cover the tip of a ballpoint pen. By comparison, older thermometers contain about 500 milligrams of mercury. It would take 100 CFLs to equal that amount. More information is here: http://www.epa.gov/mercury/
But elemental mercury is different than methymercury which is much more toxic form of mercury. We are much more concerned about the disposal of CF bulbs, because mercury is not released unless the bulbs are broken. Many broken bulbs in landfills can result in the elemental mercury leaching into ground water where it is converted into methymercury and deposited into fish and shellfish. Ingesting fish and shellfish high in methymercury can cause serious health effects especially in fetuses, infants and children. For more information about the different forms and their health effects, visit http://www.epa.gov/mercury/effects.htm
Coal-fired power plants are the largest man-made source of elemental mercury because mercury that naturally exists in coal is released into the air when coal is burned to make electricity. Coal-fired power generation accounts for roughly 40 percent of the mercury emissions in the U.S. EPA is implementing policies to reduce airborne mercury emissions. Under regulations EPA issued in 2005, mercury emissions from coal-fired power plants will drop by nearly 70 percent by 2018.
The use of CF bulbs reduce power demand, which helps reduce mercury emissions from power plants.
Q3: What happens if I break a CF bulb? Can I throw it in my garbage?
A3: Very detailed information about what to do can be found on Energy Star's web site on mercury
Q 4: Do CF bulbs work with dimmers, photocells, timers and motion sensors?
A 4: Please see the Controls section of this page.
Q 5: Do CF bulbs work on touch lamps?
A 5: No because touch lamps work with an electronic 'on-off' device that scrambles the electronic of a CF bulb and causes it not to start.
Q 6: Can I put a regular CF bulb in a 3-way lamp?
A 6: Yes, but it may only work on the 2nd or 3rd click.
Q7: Are CF bulbs harmful to my health?
A 7: There are common myths that fluorescent lights cause headaches, rob the body of Vitamin B and can cause seizures. Many of these myths began when fluorescent lights first came into being in the 1940's. At that time, the phosphors (white coating on the inside of the glass tubes) were very primitive and gave off an unnatural and unpleasant bluish-green color causing people to look jaundiced or sick. The old-style tubes also produced excessive glare that prompted some people to squint and get headaches. And the ballasts were magnetic which caused the lights to flicker at 60 Hz (cycles per second). This just-barely perceptible flickering was annoying to some, and was blamed for headaches and seizures, although this effect was never proven. Today's fluorescent tubes and bulbs are vastly improved. State-of-the-art rare earth phosphors show true colors and natural skin tones. And flicker is totally eliminated with new electronic ballasts that operate as high as 20,000 Hz.
Q 8: The light from my CF bulb seems too white, not warm like my old incandescent bulb. What can I do?
A8: CF bulbs used to come only in higher color temperatures like 3000K or 3500K. This is the color of light we are accustomed to in offices and stores. A 3000 K bulb might also be fine for a kitchen, bathroom or workroom, but many people prefer warmer tones for their living and dining rooms. You can now find CF bulbs in warm colors similar to incandescent bulbs - look for a color temperature of 2700K on the package.
Q 9: Can I use a photocell that installs in the socket beneath my CF bulb?
A 9: No. These types of photocells alter the voltage of the CF bulb and will cause the bulb to fail prematurely or not start at all.
Q 10: How come it says not to use a CF bulb in an enclosed fixture?
A 10: Even though CF bulbs give off much less heat than their incandescent equivalents, the heat that builds up from a CF bulb in an enclosed fixture can cause the ballast to fail prematurely. Heat is the worst enemy of ballasts. It is not a safety hazard, but can reduce ballast life 10-50%, depending on how long the CF bulb is on at any one time. It is less of a problem in outdoor fixtures.
Q 11: I bought a 15-watt CF bulb to replace my 60-watt regular bulb. It seems dimmer. Why?
A 11: There are several reasons:
- Light from an incandescent is called a "point source". All the light comes from a single filament resulting in a large glare when you stare at it. But with a CF bulb, the light is distributed evenly from all around the tubes so when it meets your eye, it seems less bright.
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The light does not travel as far. That's why we don't recommend putting CF bulbs in recessed fixtures. They don't have the "punch" that incandescent sources have.
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When under a lamp shade, less light travels down to your task; for instance when you are reading or knitting. More lumens go up from the shade. That's why we recommend using a circular CF bulb for use under a lamp shade when you need task lighting.
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After about half of the CF bulb's life, light output can decrease by as much as 25%. But if you buy an Energy Star labeled CF bulb, it must lose no more than 10% of its total light output at 40% of its rated life.
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Most CF bulbs take 30-90 seconds to come up to full brightness, except reflector bulbs which take longer.
Q 12: When my Sun Park CF bulb burned out, it smelled funny and smoked. Are these bulbs a fire hazard?
A 12: SCL distributed over 200,000 Sun Park CF bulbs in 2001 as part of the Conservation Kits. Since then, there have been about 8 complaints of premature failure accompanied by a foul-smelling smoke. A Sun Park representative gave us the following explanation.
When the glass tubes are roughly handled (when screwed into a socket by holding the glass tubes for instance), the vacuum inside the tubes is lost. Oxygen can then come into contact with the tungsten filament at the base of the glass tube (the filament assists with bulb start) causing the filament to overheat. This overheating causes: 1) premature bulb failure, and 2) the epoxy glue that holds the glass tubes to the base to melt, smoke and turn black.
We were assured that the plastic base is not burning or melting, as it's a high temperature lexon material that is UL approved as a material appropriate for high heat (although it will darken when exposed to high heat.) What actually is melting and smoking is the epoxy glue. Sun Park said there is a cut-off switch inside the ballast (required for UL approval) which prevents the electronics in the ballast to burn when exposed to excess heat.
Sun Park has distributed over 1 million bulbs throughout the Northwest and has less than 20 complaints of premature failure and smoking, but no fires. Sun Park stated that rough handling during production or the shipping can also loosen the seal and cause premature failure and epoxy smoking. Sun Park will gladly replace for free any bulb that fails prematurely. They can be reached at 1.310.320.7880 or mvelasco@sunpkco.com.
Q 13: I don't want to buy any CF bulbs that are not made in the US. What brands are those?
A 13: There is only one CF bulb manufacturer, Lights of America, whose bulbs are assembled in the US. But many of their parts come from off-shore. All the major brands, Sylvania, GE, Philips, Westinghouse, TCP, Feit, Greenlite, Satco and Globe to name a few, have their bulbs made off-shore. In fact, most all of the products we buy or consume come from outside the US. Buying only CF bulbs with the Energy Star label assures you they have met very strict quality standards, regardless of their country of origin.
Q 14:These bulbs sound a major hassle. Why should I bother using them?
A 14:Well, there are several conditions under which CF bulbs will not work, but there are even more places where they will work. And once you find the right places to put them, you can forgot about them for 5 years which is how long they'll last if on an average of 3 hours/day. Not only that, you'll have the same amount of light for 75% less the cost!
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What's New:
· Twist & Save with energy-efficient light bulbs at new low prices! See participating retailers, disposal information and a video of your favorite Seattle celebrities twisting and saving!!
· Recycle your Fluorescent Bulbs and Tubes
The Take it Back Network now provide options for collecting burned out fluorescent bulbs and tubes! Visit their website for a list of retailers that will accept the products and recycle them safely.
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