Compact fluorescent lightbulbs
Compact fluorescent lightbulbs (CFLs) are energy-efficient lighting alternatives to traditional incandescent bulbs, first introduced in the mid-1990s. They are designed to consume up to 75% less energy and last up to ten times longer, making them a popular choice for energy conservation and reducing waste. CFLs operate by igniting gas to produce ultraviolet light, which then creates visible light through a fluorescent coating, in contrast to the heat-based method used by incandescent bulbs. While they can fit into most standard fixtures, certain conditions, such as high temperatures in enclosed fixtures or frequent on-and-off use, can negatively impact their efficiency and lifespan.
However, CFLs contain a small amount of mercury—approximately 4 milligrams per bulb—necessitating careful disposal to prevent environmental harm. Various state regulations in the U.S. prohibit their disposal in landfills, and specific precautions are recommended in the event of a breakage to manage potential mercury exposure. Overall, CFLs present a balance of energy efficiency and environmental responsibility, provided users handle them with care during disposal.
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Compact fluorescent lightbulbs
DEFINITION: Lightbulbs that consume less energy and radiate a different light spectrum than incandescent bulbs and are designed to replace them
Compact fluorescent lightbulbs can have positive impacts on the environment in that they last longer than traditional incandescent lightbulbs and use significantly less energy than incandescents, so they create less waste and aid in energy conservation. Because compact fluorescent bulbs contain mercury, however, care must be taken in their disposal to avoid doing environmental harm.
Compact fluorescent lightbulbs (CFLs) were first introduced as an energy-saving alternative to traditional incandescent lightbulbs during the mid-1990’s. They use less energy and have longer life spans than incandescent lightbulbs, which they are designed to replace. CFLs can use up to 75 percent less energy and last up to ten times longer than incandescents. CFLs can be used in most of the same lighting fixtures as incandescent bulbs, but different types of CFLs have been created for compatibility with various types of lighting fixtures, including those that use dimmer switches, three-way lamps, and outdoor fixtures.
Several kinds of fixtures and circumstances can reduce the overall efficiency of CFLs; enclosed light fixtures, for example, can create high temperatures that can shorten CFLs’ life, and CFLs cannot withstand extremely low temperatures. Additionally, CFLs should not be used in fixtures that vibrate, including ceiling fans and garage door openers. The efficiency of CFLs is greatly reduced when they are turned on and off frequently, as most CFLs take at least three minutes to warm up and emit their maximum light.
CFLs and incandescent lightbulbs use different methods to produce light, which accounts for the different amounts of energy they use. An incandescent bulb produces light by running an electrical current through a wire to heat a filament. A CFL produces light by using electricity to ignite a gas within the bulb to produce invisible ultraviolet light, which then produces visible light by exciting a fluorescent white coating (phosphor) inside the bulb. A ballast regulates the electrical current within the bulb. After the gas within the CFL is ignited, the amount of electricity needed to keep the bulb lighted is significantly less than that used to heat the filament in an incandescent bulb.
State and local governments in the United States have set rules regulating the disposal and of broken and intact CFLs because these bulbs, like all fluorescent bulbs, contain small amounts of mercury; on average, each CFL contains about 4 milligrams (0.00014 ounce) of mercury. When a CFL is intact, no amount of mercury is released, but mercury may be released from a broken CFL. According to the Environmental Protection Agency (EPA), California, Maine, Massachusetts, New Hampshire, Vermont, and Washington have state laws that prohibit bulbs containing mercury to be deposited in landfills. The EPA advises that the following special precautions should be taken when a CFL breaks, to avoid the possibility of mercury exposure. All people and animals should leave the room in which the bulb was broken, and the room should be allowed to air out for at least fifteen minutes. Disposable materials should then be used to clean up the remnants of the bulb, and all the cleanup materials should be disposed of immediately, along with the broken bulb and its remnants, in a glass jar or plastic bag that can then be sealed. The jar or bag should then be disposed of according to guidelines for disposal of toxic materials set by the local government.
Bibliography
Chiras, Daniel D. “Foundations of a Sustainable Energy System: Conservation and Renewable Energy.” In Environmental Science. 10th ed. Sudbury, Mass.: Jones and Bartlett, 2014.
Goldblatt, David L. Sustainable Energy Consumption and Society: Personal, Technological, or Social Change? Norwell, Mass.: Springer, 2005.
Krigger, John, and Chris Dorsi. The Homeowner’s Handbook to Energy Efficiency: A Guide to Big and Small Improvements. Helena, Mont.: Saturn Resource Management, 2008.
"Recycling and Disposal of CFLs and Other Bulbs that Contain Mercury." Environmental Protection Agency, 6 June 2024, www.epa.gov/mercury/recycling-and-disposal-cfls-and-other-bulbs-contain-mercury. Accessed 16 July 2024.