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Lighting Myth: You should never turn off fluorescent lights.

When fluorescent lights first came into use in the 1950s, people developed the habit of leaving the lights on. Like many myths, this one has lived well past its useful life.

As a general rule, you should turn off the lights whenever you leave a room. It's just a good habit to develop. Turning off the lights reduces operating costs in two ways: it saves energy and reduces the number of lamp replacements.

Save Energy
But doesn't it take more energy to start up the light than it does to run the lamp for several minutes? In a word: No. It is true that fluorescent lamps draw an inrush current that is five times greater than the operating current. However, the initial surge of a rapid start lamp lasts for only 1/120th of a second. So, you have to turn the lamp off for only one second to save the same amount of energy used to start it up again.

Reduce Lamp Replacements
But, doesn't the starting cathode erode each time the lamp is started? Yes. Cathode erosion is one factor that limits lamp life. While turning off the lights reduces the number of hours the lamp will burn, it extends the time between lamp replacements. For example, a standard rapid-start fluorescent lamp operating continuously will burn for 38,000 hours or 4.3 years. If the same lamp burns only 12 hours per day, the number of operating hours drops to 30,000. However, the lamp will remain in service for 6.8 years. So, you cut operating energy in half and reduce lamp replacement costs by 30 percent. It's not necessary to go through elaborate calculations each time you leave a room. As general rule of thumb, it's always better to turn off the light, even if you'll be gone only a minute or two. Make a habit of turning off the lights every time you leave.

Forty years ago, leaving the lights burning continuously may have been the best thing to do. However, a few things have changed since then. Fluorescent lamps are more durable, energy is several times more expensive, and fluorescents are used in more locations than ever before. If you want to save money on energy and lamp replacement, turn it off!

One reason that some lights burn continuously is that building staff don't know which switches to flip. For example, in a retail store, staff may arrive at 7 a.m., but business hours don't begin until 10 a.m. Only a portion of the lights needs to be on before opening time. To solve this problem, EWEB provides Switch Hitter™ stickers that identify how to operate lighting circuits. The stickers can be applied to a service panel or wall-mounted light switches. EWEB provides Switch Hitters free, but quantities are limited. Call Energy Management Services today.