If every American home replaced just one light with an energy efficient compact fluorescent light bulb (CFL), we would save enough energy to light more than 3 million homes for a year, about $700 million in annual energy costs, and prevent 9 billion pounds of greenhouse gas emissions per year, equivalent to the emissions of about 800,000 cars.

Compact Fluorescents (CFL's) provide more light with less power. They typically require less than one-third the energy to produce the same amount of light, as common incandescent bulbs.



Compact fluorescent light bulbs (CFLs) originally qualified for the ENERGY STAR label in 1999.
An ENERGY STAR qualified compact fluorescent light bulb (CFL) will save about $30 over its lifetime and pay for itself in about 6 months. It uses 75 percent less energy and lasts about 10 times longer than an incandescent bulb.

First, CFLs use significantly less energy -- 75 percent less energy than incandescent light bulbs. That means CFLs require less wattage to produce an equivalent amount of light. For example, you could use a 20-watt CFL and enjoy the same amount of light as a 75-watt incandescent.

Of course, if you're using less energy, your energy costs are going to go down. Replacing a standard 60-watt bulb with a 13-watt CFL can save a single household $30 in energy costs over the life of the bulb.

Even with the higher price tag of CFLs -- you'll pay $2 to $4 for a CFL versus 30 to 40 cents for a typical incandescent bulb -- they still save you money. That's because CFLs last a long time. In some tests, they burned brightly for 10,000 hours, whereas standard bulbs burned for just 800 to 1,500 hours.

The environment comes out ahead, too. A good deal of electricity coming from coal-fired power plants gets directed to the lamps and light fixtures inside your house. If you're saving energy by using CFLs, then you're pulling less electricity from the power grid. This reduces the amount of coal that must be burned, which reduces emissions of greenhouse gases. In a single year, the use of CFLs over incandescent bulbs removes as much greenhouse gas pollution as taking 2 million cars off the road.

These would be dubious benefits if CFLs didn't perform well or couldn't be used in many applications, but they are, in fact, quite versatile. Several manufacturers make compact fluorescent light bulbs that can be used with dimmer switches and in three-way lamps. And many CFL bulbs can be used outdoors as long as the fixture is enclosed. Most importantly, they give off good light. In a 2007 study conducted by Popular Mechanics, CFLs burned almost as bright and produced a better quality light than a 75-watt incandescent bulb.

Compact Fluorescent Lamp	Incandescent Light Bulb
A compact fluorescent bulb activates phosphor to produce light. A phosphor coating inside the lamp gives off light when it is exposed to ultraviolet radiation. The bulb doesn't use heat to create light, which makes it more energy efficient.	A regular (incandescent) bulb produces light by heating a filament inside the bulb. Electric current passes though the filament, heating it to the point that it becomes white-hot and emits light. Most of the electric energy incandescent bulbs use is converted into heat.
CFL Wattage (23 Watt)	Incandescent Wattage (100 Watt)
Average life: 10,000 hours	Average life: 750 hours
Average cost: $4.00/ per bulb	Average cost: 75 cents/ per bulb
Comparable lighting: 1,500 lumens	Comparable lighting: 1,690 lumens
3 year cost comparison: Electricity cost*: $8.06	3 year cost comparison: Electricity cost: $35.00
Bulb cost: $4.00 (1 bulb for 6.8 years)	Bulb cost: $4.50 (6 bulbs for 3 years)
Total cost: $12.06	Total cost: $39.50

* At 8 cents/kilowatt-hour, four hours burned per day.


Choosing between the various types of CFLs and deciding where to use them can be daunting. Here you'll find guidance on choosing the right bulbs for your fixtures and locating a convenient retailer. For an interactive learning experience, click on the Choose a Light Guide.