A compact fluorescent light (commonly known as a CFL) is a more energy-efficient alternative to a standard incandescent light bulb. CFLs can be used almost anywhere incandescent bulbs are used: in recessed fixtures,table lamps, ceiling fixtures, porch lights, vanity bars and more. CFLs last at least 6 times longer than standard incandescent bulbs and use less energy to operate.

CFL technology has several advantages over incandescent lighting technology: it is four times more efficient and lasts at least 6 times longer; it uses about 75% less energy; and produces 75% less heat while delivering more light. In addition, it provides a flicker-free start and soft-white light, is environmentally friendly, and comes in a variety of styles.

Although CFLs may be more expensive to purchase initially, you save money in the long run because CFLs use less energy and last longer.

Just like incandescent bulbs, CFLs come in different color “temperatures” (e.g. soft white, day light, bright white). If you want a light most like an incandescent, choose a CFL with a temperature around 2700K. For whiter task lighting, choose a higher temperature, around 3500K. The higher the color temperature, the bluer the light will appear.

Yes, certain ENERGY STAR qualified CFLs are made to work on dimmers. Be sure to check the fine print on the back of the packaging for the proper applications. Dimming an ENERGY STAR qualified CFL that is not designed to work on a dimmer switch can shorten its life significantly. To find a list of retailers that carry dimmable CFLs, visit aps.com/cfl. Click on Find a participating retailer link for a list of stores and which types of CFLs they carry. Your local hardware store may not stock a wide variety of dimmable CFLs, so if you are looking for a specific wattage or bulb type, you may also want to try to purchase it online.

Finding an ENERGY STAR qualified CFL that will put out the same amount of light (lumens) as your current 60W incandescent bulb is easy. A watt is actually a measure of power consumption. When purchasing a light bulb, what you are really after is light output, which is measured in lumens. When you purchase a 60-watt incandescent bulb, you are getting about 800 lumens. By selecting a 13-Watt or 14-Watt ENERGY STAR qualified CFL instead, you can still get 800 lumens, but it requires much less power. The new Lighting Facts labels on bulb packages, much like nutrition labels on food, help you choose how to find the right bulb. Look for the Brightness box on the label and select a bulb that produces at least 800 lumens. Brightness is measured in lumens; the higher the number, the brighter the light.

ENERGY STAR qualified products have been tested to meet stringent performance criteria established by the EPA and DOE. The criteria ensures that all bulbs earning the ENERGY STAR meet minimum lifetime and efficacy requirements, and are within maximum allowed product start and warm-up times.

Manufacturers are also required to label the product if the light output is different than that of a soft white incandescent. If you choose a bulb that is not ENERGY STAR qualified, you might not get the performance you are looking for.

ENERGY STAR manufacturer partners must certify that their product meets the strict energy efficiency guidelines set by the EPA and DOE. When they do, they may place the label on their product. As technology advances and more energy-efficient products make it to the marketplace, ENERGY STAR reviews the guidelines for each product category and strengthens them as necessary to ensure that, generally, only the top 25% of products in each category can earn the label.

Incandescent light bulbs work by heating a tungsten filament, or wire, until it glows. This is what produces the light you see. Unfortunately, 90% of the energy used to generate that light is wasted as heat, making incandescent bulbs a very inefficient way to light your home. ENERGY STAR qualified CFLs, on the other hand, create a chemical reaction among gases located inside the glass tube, causing phosphors to illuminate. This is a much more efficient way of producing light, and means CFLs produce far less heat.

Turning a CFL on and off frequently can shorten its life. To take full advantage of the energy savings and long life of ENERGY STAR qualified CFLs, it is best to use them in light fixtures you use the most and leave on for at least 15 minutes at a time. Good locations include outdoor light fixtures, indoor fixtures in the living room, family room, kitchen, bedroom, recreation room, etc. This is not to say you should leave your lights on all day if you use ENERGY STAR qualified CFLs. It is still a good habit to turn the lights off when you leave the room for an extended period.

Yes! Always read the packaging of the CFL to be sure of its proper application, but there are a wide variety of ENERGY STAR qualified CFLs that are designed for use in most fixtures in your home or business.

Product types include:
Incandescent shape (or A-shaped) and globes – both are good in fixtures where the bulb is exposed, or in fixtures with clamp lamp shades.
Reflectors – intended for nondimmable track lighting and recessed cans, and some weather-protected outdoor spot lights.
Candle shapes – for use in some porch lights, in wall sconces and in some chandeliers.
Spirals and mini-spirals – the most versatile, which are getting smaller and smaller in size and can be used in almost any fixture, especially table and floor lamps with harped shades.

Some CFLs are qualified to be used in 3-way and dimmable fixtures (like chandeliers, recessed lights or track lighting).

Replacing incandescent light bulbs with ENERGY STAR qualified CFLs right away, rather than waiting until they burn out, is beneficial because you can begin to start saving energy and money right away, as well as reduce greenhouse gas emissions. Instead of throwing away the incandescent bulb, you can always save it for areas where CFLs aren’t suitable (like in a closet where the light would only be on for a few minutes at a time). CFLs provide the most savings in applications where the light is on for at least two hours a day.

Using a regular CFL on a dimming switch or circuit will cause performance issues and shorten its rated life. If you are planning to use CFLs on dimming switches or circuits, please look for a CFL product that has the word "Dimmable" on its packaging. The reason these CFLs perform better is that the ballast can handle the reduction in power to the unit. The dimmable CFL will not flicker, hum or have a huge shift in color.

ENERGY STAR qualified fixtures permanently replace standard incandescent fixtures and come with pin-based CFLs that are tested to last at least 10,000 hours (about 7 years, on average). Pin-based CFLs have a two-pronged base that “plugs in” to a fixture rather than a screw base. ENERGY STAR fixtures come in hundreds of attractive styles, including table, floor and desk lamps, and in hard-wired styles for ceilings, walls, bathrooms, kitchens, dining rooms and outdoors.

Because CFLs contain a small amount of mercury, the EPA recommends that consumers take advantage of local recycling options for CFLs, where available. Consumers can search for a participating recycler in their area by going to the Participating Retailers tab, entering in their zip code, and looking for retailers with a green recycle triangle next to their name. Consumers can contact their local municipal recycling facility directly, or go to www.lamprecycle.org and click on “State Lamp Recycling Regulations & Contacts" to identify local recycling options. You can also check with your local The Home Depot store, which may offer CFL recycling. If there are no recycling options near you and you must put CFLs in the garbage, put the CFL in two sealed plastic bags. CFLs should not be disposed of in an incinerator.

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