Fluorescent CFL Light Bulbs: How Long Should they Last?
Everyone asks us how long should a CFL REALLY last?
We tell them it depends on many things. First of all, the number of times you turn a CFL on and off will affect the life of a CFL bulb. The Energy Star Life Testing Program tests all of the bulbs in a condition where they are left on for 3 hours each day. They are only turned on and off once each day. Starting a CFL puts stress on the lamp because you are applying a high voltage to the tube to “excite” the phosphorous and Amalgem inside the tube and this is what creates the light. The more you do this the more you wear down the tube. A CFL does well when it is turned on no more then 5 times a day. If you are expecting to be turning on and off a light more then that each day, expect that the life of your CFL will be reduced by 30% or so. This is not a problem for most people because you still save money versus non energy efficient incandescent lighting….but you should know about it.
The other thing that has a great effect on the bulb is using the wrong bulb in any given lighting application. For instance, if you use a high wattage spiral bulb in a recessed can you can expect to see a greatly reduced life on that bulb. Reflector bulbs are built for recessed can applications. The “reflective” surface inside the bulb actually reflects the light (and hence a portion of the heat) down and away from the recessed can. This creates the perception of having more light in the room. If you were to install the same wattage regular CFL spiral up in the recessed can area you would find that it gives off MUCH LESS light into the room versus the Reflector.
What we see many companies and individuals doing to save money is to purchase a higher wattage regular spiral bulb (a typical R30 is 15 watts so they will put in a 23 or 26 watt regular spiral bulb) and install that in the recessed can. We see many restaurants and hotels doing this. This higher wattage CFL gives off much more heat and then that heat is trapped up inside the recessed can. This heat then affects the electronics inside the integrated ballast and reduces the life of these components drastically. When you install a high wattage CFL inside these cans you can expect to see up to a 50% reduction in life.
Depending on the quality of the CFL you may see as much as a 70% reduction in life! Some people may now be wondering why higher wattage incandescent bulbs are not effected by this heat inside the recessed can, after all a 60 watt or 75 watt incandescent bulb puts off much more heat then a 26 watt CFL when installed into a recessed can. The reason the incandescent bulb is not affected by this heat is that incandescent bulbs don’t have an integrated ballast, so there are NO electronics inside an incandescent bulb to fail!
We tell them it depends on many things. First of all, the number of times you turn a CFL on and off will affect the life of a CFL bulb. The Energy Star Life Testing Program tests all of the bulbs in a condition where they are left on for 3 hours each day. They are only turned on and off once each day. Starting a CFL puts stress on the lamp because you are applying a high voltage to the tube to “excite” the phosphorous and Amalgem inside the tube and this is what creates the light. The more you do this the more you wear down the tube. A CFL does well when it is turned on no more then 5 times a day. If you are expecting to be turning on and off a light more then that each day, expect that the life of your CFL will be reduced by 30% or so. This is not a problem for most people because you still save money versus non energy efficient incandescent lighting….but you should know about it.
The other thing that has a great effect on the bulb is using the wrong bulb in any given lighting application. For instance, if you use a high wattage spiral bulb in a recessed can you can expect to see a greatly reduced life on that bulb. Reflector bulbs are built for recessed can applications. The “reflective” surface inside the bulb actually reflects the light (and hence a portion of the heat) down and away from the recessed can. This creates the perception of having more light in the room. If you were to install the same wattage regular CFL spiral up in the recessed can area you would find that it gives off MUCH LESS light into the room versus the Reflector.
What we see many companies and individuals doing to save money is to purchase a higher wattage regular spiral bulb (a typical R30 is 15 watts so they will put in a 23 or 26 watt regular spiral bulb) and install that in the recessed can. We see many restaurants and hotels doing this. This higher wattage CFL gives off much more heat and then that heat is trapped up inside the recessed can. This heat then affects the electronics inside the integrated ballast and reduces the life of these components drastically. When you install a high wattage CFL inside these cans you can expect to see up to a 50% reduction in life.
Depending on the quality of the CFL you may see as much as a 70% reduction in life! Some people may now be wondering why higher wattage incandescent bulbs are not effected by this heat inside the recessed can, after all a 60 watt or 75 watt incandescent bulb puts off much more heat then a 26 watt CFL when installed into a recessed can. The reason the incandescent bulb is not affected by this heat is that incandescent bulbs don’t have an integrated ballast, so there are NO electronics inside an incandescent bulb to fail!