The Energy Independence and Security Act of 2007 requires most screw-in light bulbs to use at least 27 percent less energy by 2014. CFLs, LEDs and some halogen bulbs meet that requirement. Standard incandescents do not and are being phased out.
As of Jan. 1, 2012, 100-watt bulbs were no longer being made or imported but could be sold until supplies run out. The 75-watt incandescent bulb is going away in 2013, and a year later it's lights out for 60- and 40-watt bulbs.
Why are incandescent bulbs being phased out? In short, because they waste energy. Less than 10 percent of the energy used by the bulb produces light; the rest escapes as heat.
There are an estimated 6 billion light bulbs in American homes, according to the Department of Energy, and more than 3.6 billion are standard incandescent light bulbs. You can see how all this wasted energy adds up.
Consumer Reports' latest light bulb tests found that many of the problems of earlier versions of replacement bulbs have been overcome. But there are some pros and cons to each type.
Pros: They're inexpensive and instantly emit a warm light in all directions, accurately revealing the colors of objects and skin tones.
Cons: They use significantly more electricity than energy-saving bulbs, and most last about 1,000 hours.
Compact fluorescent lights
Pros: They use about 75 percent less energy and last 7 to 10 times longer than incandescent bulbs. Typically, it takes less than a year to recoup the cost of most CFLs. The spirals and covered spirals give off light in all directions, making them a good choice for lamps, and the flood/reflector bulbs are more directional. Several CFL brands offer bulbs with a plastic coating that contains the mercury and any shards if the bulb breaks.
Cons: They take time to fully brighten, typically from 19 seconds for spiral bulbs to several minutes or more for flood/reflector bulbs, especially when used outdoors in frigid temperatures. Most CFLs aren't dimmable, and since frequently turning them on and off affects the bulbs' performance and life, they shouldn't be used in certain sockets. CFLs contain mercury, and while the amount is small and has decreased substantially in the bulbs Consumer Reports tested, they should be recycled.
Pros: Halogens are incandescent bulbs that use about 25 to 30 percent less energy than standard incandescents. The halogen bulbs meet the new energy-efficiency standards required by federal law and will not be phased out with standard incandescent bulbs. Halogen bulbs instantly produce light and are fully dimmable. The A-type bulbs cast light in all directions and accurately reveal the color of furnishings.
Cons: Some do not last much longer than standard incandescent bulbs, yet they cost more.
Light-emitting diode bulbs
Pros: They use slightly less energy than CFLs, and manufacturers claim LEDs last 20,000 to 50,000 hours. That's about 18 to 46 years when used three hours a day. LEDs instantly brighten, even in frigid temperatures, and performance is not affected by frequently turning them on and off.
Cons: Among A-type bulbs, the type used for lamps and other applications, not all LEDs are good at emitting light in all directions. The shapes are unusual, and the bulbs are heavier. And LEDs can be expensive, although prices have been going down.
Consumer Reports: www.consumerreports.org