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Publisher's Letter

Compact fluorescent lights are not economic.

By Leo Simpson

While most people don’t worry at all about their electrical energy consumption, more and more people are becoming efficiency conscious and are doing as much as they can to save electricity. One recommended way of doing this has been to install compact fluorescent lamps (CFLs) in place of standard incandescent lamps. All the electricity authorities promote the use of CFLs and indeed, Sydney’s "Energy Australia" is currently giving away CFLs to domestic customers.

On the face of nominal power consumption ratings, a CFL is a far better proposition than an incandescent. For example, a 15W CFL is typically quoted as having a light output equivalent to a 75W incandescent lamp.

That’s a big saving in energy and and easily justifies the much higher price of CFLs, in view of their much longer rated life which is typically quoted as five to eight times the life of an incandescent lamp. But in our experience and the experience of many others, they simply don’t last that long. In fact, our experience has been that they often don’t even last as long as a typical incandescent lamp.

Think about it. Given a few hours use a day, an incandescent lamp can be expected to last about a thousand hours or about a year. If your mains voltage is high, it can be a lot less and if it is low, an incandescent can last for years. On that basis, if a CFL is conservatively rated at five times the life of an incandescent, ie, 5000 hours, it should last for five years or more.

Two brands in front of me at the moment (GE and IGA Evanmax) quote an expected life of 8000 hours. That’s a very long time. So how many readers can categorically state that they have had a CFL last for 5000 hours or more? Not many, I would bet.

In my experience, they can fail much sooner than a typical incandescent because of outright failure of the ballast electronics or the tube itself fails. Not good. In fact, we tried a succession of CFLs here in our office to replace incandescents which were on all day, five days a week. We were lucky if the CFLs lasted a few weeks. My impression was that the CFLs were possibly failing because of spike voltages superimposed on the line. And maybe that’s what causes their early failure in domestic use as well.

When you are paying $10 or more for a CFL you expect them to last a very long time, perhaps even longer than a typical 36W fluorescent tube. 36W tubes in our office would probably last about three years at best and that would be about 7000 hours. But 36W tubes are much cheaper than CFLs.

CFLs have recently become much cheaper and some of the hardware chains have had them down to few dollars. But in my opinion, unless you get them as a giveaway from your local electricity distributor, "they’re not worth a candle". Which is a great pity because the concept is good.

Next time you go out to buy a CFL, take note of any lifetime claims on the packaging, keep your receipt and the packaging, and be prepared to ask for a refund or replacement if the unit fails prematurely. Otherwise, you could be throwing your money away.

Leo Simpson

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