About CFLs


  • They use up to 75% less energy than incandescent bulbs
  • Fit in most fixtures - indoors and out
  • Last for at least five years*
  • Provide excellent lighting
  • Recover their costs through energy savings
* Based on three hours of use per day


CFLs produce much less heat than regular, incandescent light bulbs because they work on a different principle. An electric current passes through a gas sealed in a glass tube, creating invisible ultraviolet rays. When these rays strike the special phosphor coating on the inside of a fluorescent tube, light is produced using about one quarter the energy required for the same amount of incandescent light.


Definition: A Compact Fluorescent Light produces light when electricity is passed through a gas sealed in a glass tube, creating UV rays which react with a phosphor coating on the inside of the glass tube. CFLs use less power, release less heat, and last a lot longer than an incandescent light bulb.



Incandescent Light

Definition: A bulb that uses the ohmic resistance in a conductor to produce light upon the passage of an electrical current through it. The conductor is usually in the form of a wire or filament.



  • Many styles of CFLs, look like they are twisted or can look like regular incandescent light bulbs.
  • CFLs last longer and consume up to 75% less energy than standard bulbs
  • Energy efficiency pays. The average Canadian home has 30 light fixtures that consume close to $200 worth of electricity every year.
  • By replacing just five bulbs with ENERGY STAR® qualified CFL bulbs in areas that require more than three hours of light a day saves approximately $30 a year.
  • According to the Clean Air Foundation (CAF) if every household and business in Toronto replaced just two bulbs, we could eliminate 17,667 tonnes of green house gas emissions annually.

Regular incandescent light bulbs have changed very little since their invention in the 1800's. They use a lot of energy - less than 10% of the energy they consume is used for lighting. The remaining 90% is wasted in the form of heat.

The next time you need to replace some light bulbs, remember that each ENERGY STAR qualified CFL bulb you purchase is equal to 6 to 10 regular incandescent light bulbs and uses up to 75% less energy.

Look for compact fluorescent bulbs wherever you find incandescent bulbs.

When purchasing light bulbs, it is important to know that the wattage rating listed on the bulb and packaging isn't a measure of light output, but a measure of the energy the bulb uses. For more information visit www.oee.nrcan.gc.ca/ and irc.nrc-cnrc.gc.ca/.

Source: Natural Resources Canada