Fluorescent Lighting 101
Fluorescent is still considered one of the more energy-efficient forms of lighting for the amount of light that is produced for a given amount of energy consumed. A common misconception regarding fluorescent lights are that they need to be turned off for a half hour before the energy saved equals the energy used to initially energize the lamp. Not true. Fluorescent lamps only have to be turned off for one second in order to save the amount of energy that will be expended when the lights are initially turned on again.
No Flickering Allowed
When choosing fluorescent light fixtures choose the right electronic ballast to ensure the light turns on right away without flickering and does not emit a humming sound. If a fluorescent light fixture is flickering like a strobe when you first turn it on, it likely has a bad ballast.
Ever seen a fluorescent lamp "barber-pole" or have swirling bands of light down the length of the tube? One cause may have been the way it was stored before installation. If a lamp case is stored on end in an unheated room, the mercury in the lamps will likely condense into droplets and pool in the lamp end caps. The problem may fix itself in a few days, but be sure to store fluorescent lamps in a horizontal position at temperatures above 50 degrees Fahrenheit.
Here is another common misunderstanding when it comes to fluorescent lights - turning a fluorescent fixture on and off frequently will shorten the life of the lamp and therefore waste money. False. While switching fluorescent on and off does reduce lamp life, it also reduces the operating time that the lamp is actually turned on. For example, let's consider a 4-foot linear fluorescent light operating continuously for 24 hours per day that has a rated life of 38,000 hours. Since a year has 8,760 hours, this lamp would burn out in about 4.3 years on average. On the other hand, this same lamp operating 12 continuous hours per day would have a lower rated life of 30,000 hours. Although the lamp life has been reduced by 8,000 hours or 21%, the operating time has been reduced by 50% and the "calendar life" has been increased to 6.8 years, on average. In this latter case, both lamp replacement costs and energy costs have been substantially reduced even though the rated life has been reduced.
Many people want the light produced by a fluorescent fixture to be similar to an incandescent light. The color temperature will tell you how the light will appear in terms of "warmth" or "coolness." Look for a color temperature of 3000K for the warm yellow glow that is characteristic of an incandescent light instead of the cooler white-blue light that is often associated with older styles of fluorescent fixtures.