Compact fluorescent bulbs are an important part of the solution to our nation’s energy problems. The EPA estimates that if every household were to switch to CFL’s, it would be equivalent to removing one million cars from the road. This is because they use 70% less electricity, give off five times more light, emit 90% less heat, and last 10 times longer than regular light. In fact, five CFLs can save a household as much as $300 over their lifetime. However, some have expressed concerns about the new technology, especially because they contain mercury. This page attempts to address some of these frequently asked questions.
What is a CFL?
A compact fluorescent light bulb (CFL) is fluorescent lighting designed to be used in a standard (incandescent) light bulb socket. Because incandescent bulbs work by heating up a metal filament until it is white-hot, they produce mostly heat, which is why a fluorescent bulb using only 13 watts of electricity can produce light comparable to an incandescent using 60 watts.
How does a CFL benefit the environment?
Each 13-watt CFL, over the expected 10,000 hour life of the bulb, will save 470 kilowatt hours (kWh) of electricity compared to a 60-watt incandescent. If your electricity comes from coal-fired powered plants, this translates to a reduction of over 730 pounds of carbon dioxide (which contributes to global warming), 1.6 pounds of nitrogen oxides (which contributes to ozone and acid rain), and 4.3 pounds of sulfur dioxide (which contributes to haze and acid rain).
Where can I use CFLs?
A 13-watt CFL is only 1/2 inch longer than a standard incandescent bulb. Though thicker near the base, it is smaller in maximum diameter, so it will physically fit almost anywhere an incandescent bulb will. Higher wattage CFL's are bigger, so they may have some size constraints. Only dimmable CFL's should be used on a dimmer, and no CFLs should be exposed to moisture. Desk, table, and floor lamps are ideal locations as are many indoor ceiling fixtures. Choose CFLs rated for the appropriate temperature for outdoor locations.
Is it true that CFLs contain mercury? Why and how much?
CFLs contain a very small amount of mercury sealed within the glass tubing – an average of 5 milligrams (roughly equivalent to the tip of a ball-point pen). Mercury is an essential, irreplaceable element in CFLs and is what allows the bulb to be an efficient light source. By comparison, older home thermometers contain 500 milligrams of mercury and many manual thermostats contain up to 3,000 milligrams. It would take between 100 and 600 CFLs to equal those amounts.
Ironically, a regular incandescent light bulb actually releases much more mercury into the environment than a CFL. CFLs prevent mercury from entering our air, where it most affects our health, by reducing energy demand at the power plant. The highest source of mercury in our air comes from burning coal, the most common fuel used in Iowa to produce electricity. A CFL uses up to 75% less energy than an incandescent light bulb and lasts up to 10 times longer. A power plant will emit 10mg of mercury to produce the electricity to run an incandescent bulb compared to only 2.4mg of mercury to run a CFL for the same time.
Nonetheless, because of their mercury content, they should be recycled properly and handled with care.
Low mercury CFLs by Earthmate can be found here
Where can I recycle CFLs?
Home Depot is now taking back spent, unbroken CFLs for recycling at no charge. In Iowa, most Regional Collection Centers take spent CFLs. Check your local transfer station or hazardous waste reclamation facility for additional recycling options. www.earth911.org may list other options.
What if a CFL breaks?
In the event that one breaks, please follow these instructions.
Isn’t fluorescent light cold?
If you prefer warm light, you can purchase bulbs that feel the same as an ordinary incandescent light (2700 Kelvin to be exact). The light color of each bulb at ShopIPL is clearly designated so you don’t have to guess. To learn more…
Don’t they flicker, take a long time to warm up, and make noise?
These were legitimate concerns when CFLs first hit the marketplace, but the technology has improved greatly since then. Give them another try. They’ve come a long way.
A special thanks to Texas Interfaith Power & Light for their assistance with this information.