CFL facts

How many energy geeks does it take to change a light bulb?

By Arnie Katz

CFL facts

Ten — one to screw in the bulb and nine to debate the economic and environmental implications.

Q: The government and environmentalists have been promoting compact fluorescent lights (CFLs) for several years. I’ve read some pretty scary reports on the Internet about mercury contamination and fires and reports from people saying they just don’t put out as much light as regular bulbs. I see them in the store and though the prices have come way down, I can’t decide whether to try them or stockpile my shed with incandescent bulbs before they’re taken off the market.

A:CFLs have only been around for about 20 years or so and as is the case with most new technologies, there is a lot we don’t know yet. Based on the best information I can find, here is what we do know.

CFLs save energy

They use about a quarter to a third of the amount of electricity to make the same amount of light as an incandescent light does. As electricity rates go higher, you’ll save more money with CFLs.

CFLs last longer

All light bulbs are given a rating on how many hours they will work. CFLs are usually rated at 10,000 to 15,000 hours, compared with incandescent bulbs rated for 750 to 1,000 hours. The “average life” listed on the label is the point at which half of the bulbs in the test have burned out and half are still working. So really, you should only expect about half of your bulbs to last as long as the life listed on the label. I have CFLs that I use a lot that have lasted more than 10 years.

CFLs contain mercury

Mercury is a toxic element that can cause serious health problems. There are potential risks associated with these bulbs, which, by the way, are also associated with the bulbs in tube fluorescents found in many schools, stores and offices. These potential risks include broken bulbs, which can expose you and your family to mercury. While there are horror stories about spending thousands of dollars for Hazmat teams in moon suits to clean up broken bulbs, most credible sources recommend more reasonable precautions. If a bulb breaks, leave the room and open a window for at least 15 minutes. Carefully clean up broken glass and any residues, and place in a sealed plastic bag or glass jar. For good instructions on how to clean broken CFL bulbs, visit the EPA website
Disposing of broken or burnt out bulbs should be done in a way that prevents mercury from entering the air or ground water. Some hazardous household waste collection sites now accept CFLs along with other hazardous items like batteries and old paint. Check with your local solid waste or recycling department.
CFLs are unlikely to cause fires

There is one anonymous claim on several websites with a scary picture of a fire allegedly caused by a CFL bulb. I have been unable to find any documented cases of CFLs actually causing fires. Just like with every electrical device there is the potential for a fire hazard, but as far as I can tell, you should be more concerned about your toasters and halogen torchiere lamps starting a fire than your CFLs.

CFLs are comparable to incandescent lights in light quality

Most CFLs take a few seconds to get up to full brightness, and some don’t give as much light as the incandescent bulb they are supposed to replace, but most do. In the early days, the quality of CFLs wasn’t always great, and a lot of people got stuck with inferior products. Today, the quality seems to be much better, and I rarely hear complaints about bulbs burning out after just a couple of months or not putting out enough light. If you tried them a few years ago and weren’t satisfied, it may be worth trying them again.

About the Author

Arnie Katz is the former building science consultant for Advanced Energy in Raleigh.

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