Generally fluorescent lamps are four to five times more efficient than incandescent bulbs. Fluorescent lamps reduce the need for power plants to burn fossil fuels to generate electricity, thereby reducing emissions including mercury, carbon dioxide and other pollutants that contribute to climate change.
These lamps also reduce solid waste, since they last longer than incandescent or halogen lamps and require less frequent replacement.
However, energy-efficient lighting products such as fluorescent lamps, CFLs, and high intensity discharge (HID) lamps contain small amounts of mercury.
The mercury is contained within the lamp and is not exposed to the environment unless the lamp is broken at the end of its life. The release of mercury is most likely to occur when the lamp is thrown in a garbage truck or a dumpster.
While lamps are not a major source of mercury pollution, the improper disposal of large numbers of lamps does add to mercury in the environment. Burning hazardous wastes or incineration of disposed materials can also release mercury into the environment. The greatest source of man-made mercury emissions, at 40%, is from fossil-fuel burning power plants.
The best way to prevent the release of mercury from lighting is to recycle lamps and not dispose of them in the solid waste stream. Recycling lamps captures the mercury, allowing it to be reused.
The US Environmental Protection Agency has special regulations for mercury-containing lamps, which eliminates excessive paperwork, alleviates transport issues, and helps keep disposal costs low, easing the path for lamp recycling.
A robust and growing business has developed to collect and recycle end of life mercury lamps from commercial buildings. Options for retail consumers are expanding rapidly as well. Many local governments now collect end-of-life lamps and some retailers such as Ikea and HomeDepot are also taking back lamps.