Re: Compact fluorescent lamps
 

I think the warm up takes longer as the CFL gets older. It seems that the slow to brighten ones are the oldest, but I certainly don't remember them being slow at all when I first put them in.

Note that they are not that dim at first, and only take a minute or three to get to full brightness. (I certainly don't mean to dissuade anyone from getting CFLs because of this!)

-- Alan

Re: Compact fluorescent lamps
 

I have yet to replace any CFL bulbs, after using them for several years. The oldest ones in the house are about 3 years old, so no longevity records here... Almost all of them are the "dimmable" type, branded ULA.

The voltage makes a difference. If the voltage is slightly low (say, 110 instead of 120), fluorescent lamps last a lot longer. If the voltage is slightly high (say, 125), they fail early. That applies to all fluorescent lamps, not just CFLs.

A second difference is in how the power is initially applied. Many electronic devices don't like sudden starts. I'm not quite sure why, though. It might have something to do with the high frequency transients that occurs when the switch closes.

If you use dimmer switches, the voltage ramps up over a period of a few cycles, and the max voltage is a few volts lower than the house voltage. Of course, that requires "dimmable" lamps.

(There are "soft start" switches available. A soft-start switch is a regular switch (not a dimmer), that suppresses the high-frequency transient, so it ramps up the voltage over a period of a few dozen milliseconds. It think they just have low-pass filters, but I'm not certain. They are very expensive, though, and so are probably not really an option for household use.)

Because high-frequency and high-voltage both cause failures of CFL lamps and other electronics, it is prudent to protect them by providing surge suppression. I have a "whole-house" surge protector, too. Whole house surge protectors install on or in the main circuit-breaker panel, and cost about $100.