Compact fluorescent light bulbs are more energy efficient than standard incandescent light bulbs but have limitations that make them unable to be used in certain types of lights, such as dimmers or spotlights. Fluorescent light bulbs can last for 10,000 hours — or as much as 12 times longer than conventional bulbs. Unlike standard incandescent light bulbs that generate 90% heat and 10% light, fluorescent bulbs create light through the use of an electric current that creates ultraviolet radiation, which reacts with the fluorescent coating. The heat is trapped; therefore, fluorescent bulbs are more sensitive to temperature and typically will become dim or burn out quickly if they are used in light fixtures that build up heat quickly or for outdoor lights that are exposed to cold.
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