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CFL's - Compact Fluorescent Lights - Advantages and Problems, from Energy Savings to Toxic Mercury

compact fluorescent light CFLIntroduction

Compact fluorescent lamps (CFL's), are small household lamp-sized fluorescent lamps. They are generally intended to replace incandescent light bulbs. They have become very popular mainly due to their lower energy consumption  (about one-fourth - 25%) for the same amount of light output compared to incandescent light bulbs.  As a result, they are perceived as being "green".  But, like all man-made devises, there are advantages and disadvantages, pro's and con's to using them.  We will present these below, along with references to credible authoritative sources and some conclusions to help you decide when CFL's are right for you.  

How do CFL's work / How are they different from Incandescent Lights?

CFL's are a type of fluorescent lamps.  This means that the pass electricity through a gas, which becomes charged and emits light. Incandescent lights heat a wire (called a filament) in a vacuum until the wire glows and gives off light... and heat.  The heat is wasted energy.

 In a CFL, an electric current is driven through a tube containing argon gas and a small amount of mercury vapor. This generates invisible ultraviolet light.  But that UV light excites (energizes) a fluorescent coating (called a phosphor) on the inside of the tube, which then emits the visible light that you see.

CFL design details

CFLs have two main components: a gas-filled tube (also called bulb or burner) and a magnetic or electronic ballast. Electronic ballasts contain a small circuit board with rectifiers, a filter capacitor and usually two switching transistors connected as a high-frequency resonant series DC to AC inverter. The resulting high frequency, around 40 kHz or higher, is applied to the lamp tube. Since the resonant converter tends to stabilize lamp current (and light produced) over a range of input voltages, standard CFLs do not respond well in dimming applications and special lamps are required for dimming service.  

Standard shapes of CFL tube are single-turn double helix, double-turn, triple-turn, quad-turn, circular, and butterfly. 

Why ballasts?

CFLs need a little more energy when they are first turned on, but once the electricity starts moving, but use about 75 percent less energy than incandescent bulbs. A CFL’s ballast helps "kick start" the CFL and then regulates the current once the electricity starts flowing.

The most important technical advance has been the replacement of electromagnetic ballasts with electronic ballasts; this has removed most of the flickering and slow starting traditionally associated with typical fluorescent lighting. Older CFLs used large and heavy magnetic ballasts that caused a buzzing noise in some bulbs. Most CFLs today (including all ENERGY STAR qualified CFLs) use new electronic ballasts, which do not buzz or hum.

Lumens, efficiency and longevity

Light is measured by lumens. A traditional 75 watt incandescent light bulb produces 1170 lumens of light and lasts on average 750 hours. But a CFL that produces the 1170 lumens uses only  20-21 watts of electricity. The CFL uses only 1/4 to 1/3 the amount of energy to produce the same light as an incandescent light bulb. The long term savings are improved further because CFLS are expected to last anywhere from six to eleven times longer than their incandescent bulbs. burnout rate. An article in the Wall Street Journal on Janry 20, 2011 stated that PG&E  assumed the useful life of each bulb would be 9.4 years, but  with experience, it has cut the estimate to 6.3 years, Field tests also showed higher burnout rates in certain locations, such as bathrooms (humid) and in recessed lighting (trapped heat). Frequently turning them on and off also appears to reduce longevity.

UV Radiation

Research just published in July 2012 shows that most CFL bulb emit harmful amounts of UV (ultraviolet) radiation. See this page for more information.

Mercury

Although some companies like Sylvania managed to make small CFLs containing only 1.5 milligrams of mercury, the, the Environmental Protection Agency states that the average CFL contains 4 milligrams of mercury Here are some of the EPA's other statements about mercury in CFL's:

Mercury is widely known to be a health risk if inhaled or ingested, especially in small children, and has always been one of the downsides to CFLs. Mercury is a potent neurotoxin, and it's especially dangerous for children and fetuses. Most exposure to mercury comes from eating fish contaminated with mercury, The use of mercury in CFLs has been the concern of several consumer-advocacy groups, and the EPA has guidelines on how to handle broken CFLs, which can release a small amount of mercury if its tubes are broken. Some manufacturers have even made a CFL light bulb that can contain its mercury even in the event of a tube breakage.

Cleaning up after a broken CFL bulb

Here are some useful guides which you can download and print:
  1. Before cleanup
    • Have people and pets leave the room.
    • Air out the room for 5-10 minutes by opening a window or door to the outdoor environment. 
    • Shut off the central forced air heating/air-conditioning (H&AC) system, if you have one.
    • Collect materials needed to clean up broken bulb.
  1. During cleanup
    • Be thorough in collecting broken glass and visible powder.
    • Place cleanup materials in a sealable container.
  1. After cleanup
    • Promptly place all bulb debris and cleanup materials outdoors in a trash container or protected area until materials can be disposed of properly. Avoid leaving any bulb fragments or cleanup materials indoors.
    • For several hours, continue to air out the room where the bulb was broken and leave the H&AC system shut off.

The EPA offers a checklist at epa.gov/mercury that suggests you do not use a vacuum cleaner, as that will only spread the problem. They suggest that the next time you vacuum the area, you should then immediately dispose of the vacuum bag.

Recycling

Some states and local jurisdictions have more stringent regulations than U.S. EPA does, and may require that you recycle CFLs and other mercury-containing light bulbs. California, Maine, New Hampshire, Minnesota, Vermont and , for , for example, all prohibit mercury-containing lamps from being discarded into landfills.  Visit Earth911.com epa.gov/ng, or lamprecycle.org to contact your local waste collection agency, which can tell you if such requirement exists in your state or locality. Some retailers such as IKEA, take used CFLs for recycling. See the following paragraph for details:

How and Where Can I Recycle CFLs?

Waste collection agencies   |  Local retailers  |  Mail-back services

  1. Contact your local waste collection agency by visiting Earth911.com . Many counties and cities have household hazardous waste drop-off locations and/or curbside and other special collection programs. To find locations where you can drop off bulbs, and when and where a collection may be held in your area, contact your local waste collection agency directly by visiting Earth911.com . Note that waste collection agencies:
    • provide services that are usually free, though some may charge a small fee.
    • sometimes collect household hazardous wastes only once or twice a year, so residents will have to hold on to their light bulbs until the collection takes place. Other collection agencies provide collection services throughout the year.
    • may also collect paints, pesticides, cleaning supplies or batteries.
    • usually accept waste only from residents, although some collection programs include small businesses as well.
  2. Visit your local retailers. Ace Hardware, Home Depot, IKEA, Lowe's, Orchard Supply and other retailers offer in-store recycling. Visit Earth911.com to find stores in your area. Check directly with the store before you go; not all stores in regional or nationwide chains may be equipped to recycle. EPA is working with retailers to expand recycling and disposal options.
  3. Find out about mail-back services. Some bulb manufacturers and other organizations sell pre-labeled recycling kits that allow you to mail used bulbs to recycling centers. The cost of each kit includes shipping charges to the recycling center. You fill up a kit with old bulbs, seal it, and bring it to the post office or leave for your postal carrier.  Websites that provide more information about mail-back services  . Note that:
    • EHSO does not endorse, recommend, certify, authorize or approve of any of these services;
    • there may be other similar services of which we are not aware; and
    • we only provide these links as a convenience to our web visitors.

Disposal

Some states, cities and counties have outlawed putting CFL bulbs in the trash, but in most states the practice is legal. As of January 2011, California,  Minnesota, Ohio, Illinois, Indiana, Michigan and Wisconsin are the only states that ban disposing of fluorescent bulbs as general household waste.

Legal changes

A federal law takes effect in January 2012 requires a 28% improvement in lighting efficiency for conventional bulbs in standard wattages. Effectively this means that compact fluorescent lamps will replace traditional incandescent light bulbs, since by law, the incandescent light bulbs will not be allowed to be sold after 2014. California began phasing out sales of incandescent bulbs in January 2011, one year ahead of the rest of the nation.

Advantages / Pro's

Disadvantages

Conclusions


CFL News


Other References:

This page was updated on 26-Feb-2014