During the life cycle of any product, the mining of the raw materials, manufacturing, transportation, storage, use, and ultimately disposal, have an effect on our environment. To determine the overall effect, an environmental life cycle assessment is used. Several environmental life cycle assessments on products are frequently debated, such as coffee cups, shopping bags, diapers, and now electric lamps.
When selecting between compact fluorescent lamps (CFL), incandescent light bulbs, and light emitting diode (LED) lighting, you have to look at the whole picture, from the cradle to the grave. In a simple environmental assessment, LED lighting is the hands-down winner, but they are still quite expensive, so for now, the discussion is usually between CFL and incandescent.
While it takes about 5 times the energy to produce a CFL as compared to incandescent lamps, that still represents less manufacturing energy overall because 6 - 10 times as many incandescent lamps have to be produced to last as long as a single CFL.
During the life of a CFL, it will use about 4 times less energy than a 6-10 standard incandescent bulbs used in that same period. That means that incandescent lamps, that have no mercury contained within, will cause hundreds of milligrams more power plant mercury emissions. The extra power used will also generate about 200 pounds of greenhouse gases.
Fluorescent lamps contain mercury and most mercury finds its way into our food and our water by rain washing it out of the sky. The mercury contained in one standard fluorescent lamp will contaminate 6000 gallons of water beyond safe drinking levels. Even low-mercury lamps (there is no such thing as a mercury free fluorescent lamp) will contaminate more than 1000 gallons of water beyond safe levels. All types of fluorescent lamps should never be broken or thrown in the trash. They should be recycled by taking them to a local household hazardous waste collection program, commercial recycling company or retail take back program,
Both types of lamps, fluorescent and incandescent, may have lead components to solder the connections at the base, in the glass, and in the inside phosphor coating. At present, incandescent lamps under federal law can be disposed in the trash. However limited, there are opportunities to recycle incandescent lamps. If no recycling opportunity exists in your area check with your local household hazardous waste (HHW) collection program to see if they accept them.
General Electric has plans for a new high-efficiency incandescent lamp to be available by 2010 that will be 4 times as efficient as today's 125-year-old technology. That would mean that during the lifetime of the lamp that it would use about the same electricity as a fluorescent lamp, it contains much less lead than older incandescent lamps, and no mercury.